Sample records for pedunculopontine nucleus stimulation

  1. Pedunculopontine nucleus electric stimulation alleviates akinesia independently of dopaminergic mechanisms.

    PubMed

    Jenkinson, Ned; Nandi, Dipankar; Oram, Rebecca; Stein, John F; Aziz, Tipu Z

    2006-04-24

    The symptom of Parkinson's disease that is most disabling and difficult to treat is akinesia. We have previously shown that low-frequency stimulation of the pedunculopontine nucleus can alleviate such akinesia in a macaque rendered Parkinsonian using 1-methyl 4-phenyl 1,2,3,6-tetrahydropyridine. Here, we have extended that study to show that adding stimulation of the pedunculopontine nucleus to levodopa treatment in this Parkinsonian monkey increased its motor activity significantly more than levodopa alone. This additivity suggests that pedunculopontine nucleus stimulation may improve movement by acting at a site downstream from where levodopa therapy affects the basal ganglia.

  2. Stimulation of the pedunculopontine nucleus area in Parkinson's disease: effects on speech and intelligibility.

    PubMed

    Pinto, Serge; Ferraye, Murielle; Espesser, Robert; Fraix, Valérie; Maillet, Audrey; Guirchoum, Jennifer; Layani-Zemour, Deborah; Ghio, Alain; Chabardès, Stéphan; Pollak, Pierre; Debû, Bettina

    2014-10-01

    Improvement of gait disorders following pedunculopontine nucleus area stimulation in patients with Parkinson's disease has previously been reported and led us to propose this surgical treatment to patients who progressively developed severe gait disorders and freezing despite optimal dopaminergic drug treatment and subthalamic nucleus stimulation. The outcome of our prospective study on the first six patients was somewhat mitigated, as freezing of gait and falls related to freezing were improved by low frequency electrical stimulation of the pedunculopontine nucleus area in some, but not all, patients. Here, we report the speech data prospectively collected in these patients with Parkinson's disease. Indeed, because subthalamic nucleus surgery may lead to speech impairment and a worsening of dysarthria in some patients with Parkinson's disease, we felt it was important to precisely examine any possible modulations of speech for a novel target for deep brain stimulation. Our results suggested a trend towards speech degradation related to the pedunculopontine nucleus area surgery (off stimulation) for aero-phonatory control (maximum phonation time), phono-articulatory coordination (oral diadochokinesis) and speech intelligibility. Possibly, the observed speech degradation may also be linked to the clinical characteristics of the group of patients. The influence of pedunculopontine nucleus area stimulation per se was more complex, depending on the nature of the task: it had a deleterious effect on maximum phonation time and oral diadochokinesis, and mixed effects on speech intelligibility. Whereas levodopa intake and subthalamic nucleus stimulation alone had no and positive effects on speech dimensions, respectively, a negative interaction between the two treatments was observed both before and after pedunculopontine nucleus area surgery. This combination effect did not seem to be modulated by pedunculopontine nucleus area stimulation. Although limited in our group of

  3. Pedunculopontine nucleus stimulation improves akinesia in a Parkinsonian monkey.

    PubMed

    Jenkinson, Ned; Nandi, Dipankar; Miall, R Chris; Stein, John F; Aziz, Tipu Z

    2004-12-03

    We have studied the effects of stimulating the pedunculopontine nuclei through a fully implanted macroelectrode with a s.c. implantable pulse generator whose parameters can be programmed telemetrically, in a macaque before and after inducing Parkinsonian akinesia with MPTP. Our results show that in the normal monkey high frequency stimulation of the pedunculopontine nuclei reduces motor activity while low frequency stimulation increases it significantly over baseline. After making the monkey Parkinsonian with MPTP, unilateral low frequency stimulation of the pedunculopontine nuclei led to significant increases in activity. These results suggest that pedunculopontine nuclei stimulation could be clinically effective in treating advanced Parkinson's disease and other akinetic disorders.

  4. Unilateral pedunculopontine stimulation improves falls in Parkinson's disease.

    PubMed

    Moro, Elena; Hamani, Clement; Poon, Yu-Yan; Al-Khairallah, Thamar; Dostrovsky, Jonathan O; Hutchison, William D; Lozano, Andres M

    2010-01-01

    Postural instability and falls are a major source of disability in patients with advanced Parkinson's disease. These problems are currently not well addressed by either pharmacotherapy nor by subthalamic nucleus deep-brain stimulation surgery. The neuroanatomical substrates of posture and gait are poorly understood but a number of important observations suggest a major role for the pedunculopontine nucleus and adjacent areas in the brainstem. We conducted a double-blinded evaluation of unilateral pedunculopontine nucleus deep-brain stimulation in a pilot study in six advanced Parkinson's disease patients with significant gait and postural abnormalities. There was no significant difference in the double-blinded on versus off stimulation Unified Parkinson's Disease Rating Scale motor scores after 3 or 12 months of continuous stimulation and no improvements in the Unified Parkinson's Disease Rating Scale part III scores compared to baseline. In contrast, patients reported a significant reduction in falls in the on and off medication states both at 3 and 12 months after pedunculopontine nucleus deep-brain stimulation as captured in the Unified Parkinson's Disease Rating Scale part II scores. Our results suggest that pedunculopontine nucleus deep-brain stimulation may be effective in preventing falls in patients with advanced Parkinson's disease but that further evaluation of this procedure is required.

  5. Alpha oscillations in the pedunculopontine nucleus correlate with gait performance in parkinsonism

    PubMed Central

    Thevathasan, Wesley; Pogosyan, Alek; Hyam, Jonathan A.; Jenkinson, Ned; Foltynie, Tom; Limousin, Patricia; Bogdanovic, Marko; Zrinzo, Ludvic; Green, Alexander L.; Aziz, Tipu Z.

    2012-01-01

    The pedunculopontine nucleus, a component of the reticular formation, is topographically organized in animal models and implicated in locomotor control. In Parkinson's disease, pedunculopontine nucleus stimulation is an emerging treatment for gait freezing. Local field potentials recorded from pedunculopontine nucleus electrodes in such patients have demonstrated oscillations in the alpha and beta frequency bands, reactive to self-paced movement. Whether these oscillations are topographically organized or relevant to locomotion is unknown. Here, we recorded local field potentials from the pedunculopontine nucleus in parkinsonian patients during rest and unconstrained walking. Relative gait speed was assessed with trunk accelerometry. Peaks of alpha power were present at rest and during gait, when they correlated with gait speed. Gait freezing was associated with attenuation of alpha activity. Beta peaks were less consistently observed across rest and gait, and did not correlate with gait speed. Alpha power was maximal in the caudal pedunculopontine nucleus region and beta power was maximal rostrally. These results indicate a topographic distribution of neuronal activity in the pedunculopontine nucleus region and concur with animal data suggesting that the caudal subregion has particular relevance to gait. Alpha synchronization, proposed to suppress ‘task irrelevant’ distraction, has previously been demonstrated to correlate with performance of cognitive tasks. Here, we demonstrate a correlation between alpha oscillations and improved gait performance. The results raise the possibility that stimulation of caudal and rostral pedunculopontine nucleus regions may differ in their clinical effects. PMID:22232591

  6. Regional anatomy of the pedunculopontine nucleus: relevance for deep brain stimulation.

    PubMed

    Fournier-Gosselin, Marie-Pierre; Lipsman, Nir; Saint-Cyr, Jean A; Hamani, Clement; Lozano, Andres M

    2013-09-01

    The pedunculopontine nucleus (PPN) is currently being investigated as a potential deep brain stimulation target to improve gait and posture in Parkinson's disease. This review examines the complex anatomy of the PPN region and suggests a functional mapping of the surrounding nuclei and fiber tracts that may serve as a guide to a more accurate placement of electrodes while avoiding potentially adverse effects. The relationships of the PPN were examined in different human brain atlases. Schematic representations of those structures in the vicinity of the PPN were generated and correlated with their potential stimulation effects. By providing a functional map and representative schematics of the PPN region, we hope to optimize the placement of deep brain stimulation electrodes, thereby maximizing safety and clinical efficacy. © 2013 International Parkinson and Movement Disorder Society.

  7. Deep brain stimulation of the pedunculopontine nucleus for treatment of gait and balance disorder in progressive supranuclear palsy: Effects of frequency modulations and clinical outcome.

    PubMed

    Galazky, Imke; Kaufmann, Jörn; Lorenzl, Stefan; Ebersbach, Georg; Gandor, Florin; Zaehle, Tino; Specht, Sylke; Stallforth, Sabine; Sobieray, Uwe; Wirkus, Edyta; Casjens, Franziska; Heinze, Hans-Jochen; Kupsch, Andreas; Voges, Jürgen

    2018-05-01

    The pedunculopontine nucleus has been suggested as a potential deep brain stimulation target for axial symptoms such as gait and balance impairment in idiopathic Parkinson's disease as well as atypical Parkinsonian disorders. Seven consecutive patients with progressive supranuclear palsy received bilateral pedunculopontine nucleus deep brain stimulation. Inclusion criteria comprised of the clinical diagnosis of progressive supranuclear palsy, a levodopa-resistant gait and balance disorder, age <75 years, and absence of dementia or major psychiatric co-morbidities. Effects of stimulation frequencies at 8, 20, 60 and 130 Hz on motor scores and gait were assessed. Motor scores were followed up for two years postoperatively. Activities of daily living, frequency of falls, health-related quality of life, cognition and mood at 12 months were compared to baseline parameters. Surgical and stimulation related adverse events were assessed. Bilateral pedunculopontine nucleus deep brain stimulation at 8 Hz significantly improved axial motor symptoms and cyclic gait parameters, while high frequency stimulation did not ameliorate gait and balance but improved hypokinesia. This improvement however did not translate into clinically relevant benefits. Frequency of falls was not reduced. Activities of daily living, quality of life and frontal cognitive functions declined, while mood remained unchanged. Bilateral pedunculopontine nucleus deep brain stimulation in progressive supranuclear palsy generates frequency-dependent effects with improvement of cyclic gait parameters at low frequency and amelioration of hypokinesia at high frequency stimulation. However, these effects do not translate into a clinically important improvement. Copyright © 2018. Published by Elsevier Ltd.

  8. Computational modeling of pedunculopontine nucleus deep brain stimulation

    NASA Astrophysics Data System (ADS)

    Zitella, Laura M.; Mohsenian, Kevin; Pahwa, Mrinal; Gloeckner, Cory; Johnson, Matthew D.

    2013-08-01

    Objective. Deep brain stimulation (DBS) near the pedunculopontine nucleus (PPN) has been posited to improve medication-intractable gait and balance problems in patients with Parkinson's disease. However, clinical studies evaluating this DBS target have not demonstrated consistent therapeutic effects, with several studies reporting the emergence of paresthesia and oculomotor side effects. The spatial and pathway-specific extent to which brainstem regions are modulated during PPN-DBS is not well understood. Approach. Here, we describe two computational models that estimate the direct effects of DBS in the PPN region for human and translational non-human primate (NHP) studies. The three-dimensional models were constructed from segmented histological images from each species, multi-compartment neuron models and inhomogeneous finite element models of the voltage distribution in the brainstem during DBS. Main Results. The computational models predicted that: (1) the majority of PPN neurons are activated with -3 V monopolar cathodic stimulation; (2) surgical targeting errors of as little as 1 mm in both species decrement activation selectivity; (3) specifically, monopolar stimulation in caudal, medial, or anterior PPN activates a significant proportion of the superior cerebellar peduncle (up to 60% in the human model and 90% in the NHP model at -3 V) (4) monopolar stimulation in rostral, lateral or anterior PPN activates a large percentage of medial lemniscus fibers (up to 33% in the human model and 40% in the NHP model at -3 V) and (5) the current clinical cylindrical electrode design is suboptimal for isolating the modulatory effects to PPN neurons. Significance. We show that a DBS lead design with radially-segmented electrodes may yield improved functional outcome for PPN-DBS.

  9. The effect of low frequency stimulation of the pedunculopontine tegmental nucleus on basal ganglia in a rat model of Parkinson's disease.

    PubMed

    Park, Eunkyoung; Song, Inho; Jang, Dong Pyo; Kim, In Young

    2014-08-08

    The pedunculopontine nucleus (PPN) has recently been introduced as an alternative target to the subthalamic nucleus (STN) or globus pallidus internus (GPi) for the treatment of advanced Parkinson's disease with severe and medically intractable axial symptoms such as gait and postural impairment. However, it is little known about how electrical stimulation of the PPN affects control of neuronal activities between the PPN and basal ganglia. We examined how low frequency stimulation of the pedunculopontine tegmental nucleus (PPTg) affects control of neuronal activities between the PPN and basal ganglia in 6-OHDA lesioned rats. In order to identify the effect of low frequency stimulation on the PPTg, neuronal activity in both the STN and substantia nigra par reticulata (SNr) were recorded and subjected to quantitative analysis, including analysis of firing rates and firing patterns. In this study, we found that the firing rates of the STN and SNr were suppressed during low frequency stimulation of the PPTg. However, the firing pattern, in contrast to the firing rate, did not exhibit significant changes in either the STN or SNr of 6-OHDA lesioned rats during low frequency stimulation of the PPTg. In addition, we also found that the firing rate of STN and SNr neurons displaying burst and random pattern were decreased by low frequency stimulation of PPTg, while the neurons displaying regular pattern were not affected. These results indicate that low frequency stimulation of the PPTg affects neuronal activity in both the STN and SNr, and may represent electrophysiological efficacy of low frequency PPN stimulation. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  10. Pedunculopontine Nucleus Region Deep Brain Stimulation in Parkinson Disease: Surgical Anatomy and Terminology

    PubMed Central

    Hamani, Clement; Aziz, Tipu; Bloem, Bastiaan R.; Brown, Peter; Chabardes, Stephan; Coyne, Terry; Foote, Kelly; Garcia-Rill, Edgar; Hirsch, Etienne C.; Lozano, Andres M.; Mazzone, Paolo A.M.; Okun, Michael S.; Hutchison, William; Silburn, Peter; Zrinzo, Ludvic; Alam, Mesbah; Goetz, Laurent; Pereira, Erlick; Rughani, Anand; Thevathasan, Wesley; Moro, Elena; Krauss, Joachim K.

    2017-01-01

    Several lines of evidence over the last few years have been important in ascertaining that the pedunculopontine nucleus (PPN) region could be considered as a potential target for deep brain stimulation (DBS) to treat freezing and other problems as part of a spectrum of gait disorders in Parkinson disease and other akinetic movement disorders. Since the introduction of PPN DBS, a variety of clinical studies have been published. Most indicate improvements in freezing and falls in patients who are severely affected by these problems. The results across patients, however, have been variable, perhaps reflecting patient selection, heterogeneity in target selection and differences in surgical methodology and stimulation settings. Here we outline both the accumulated knowledge and the domains of uncertainty in surgical anatomy and terminology. Specific topics were assigned to groups of experts, and this work was accumulated and reviewed by the executive committee of the working group. Areas of disagreement were discussed and modified accordingly until a consensus could be reached. We demonstrate that both the anatomy and the functional role of the PPN region need further study. The borders of the PPN and of adjacent nuclei differ when different brainstem atlases and atlas slices are compared. It is difficult to delineate precisely the PPN pars dissipata from the nucleus cuneiformis, as these structures partially overlap. This lack of clarity contributes to the difficulty in targeting and determining the exact localization of the electrodes implanted in patients with akinetic gait disorders. Future clinical studies need to consider these issues. PMID:27723662

  11. Deep brain stimulation of pedunculopontine tegmental nucleus: role in sleep modulation in advanced Parkinson disease patients: one-year follow-up.

    PubMed

    Peppe, Antonella; Pierantozzi, Mariangela; Baiamonte, Valentina; Moschella, Vincenzo; Caltagirone, Carlo; Stanzione, Paolo; Stefani, Alessandro

    2012-12-01

    Sleep disorders are frequent non-motor symptoms in Parkinson disease (PD), probably due to multifactorial pathogeneses including disease progression, dopaminergic drugs, or concomitant illness. In recent years, the pedunculopontine tegmental (PPTg) nucleus has been considered a surgical target for deep brain stimulation (DBS) in advanced PD patients. As it is involved in controlling the sleep-wake cycle, we investigated the long-lasting effects of PPTg-DBS on the sleep of five PD patients implanted in both the PPTg and the subthalamic nucleus (STN) by rating two subjective clinical scales for sleep: the Parkinson's Disease Sleep Scale (PDSS), and the Epworth Sleepiness Scale (ESS). Sleep scales were administered a week before surgery (T0), three months after DBS (T1), and one year later (T2). In this study, STN-DBS was kept constantly in ON, and three different patterns of PPTg-DBS were investigated: STN-ON (PPTg switched off); PPTg-ON (PPTg stimulated 24 h/day); PPTg-cycle (PPTg stimulated only at night). In post-surgery follow-up, PD patients reported a marked improvement of sleep quality in all DBS conditions. In particular, stimulation of the PPTg nucleus produced not only a remarkable long-term improvement of nighttime sleep, but unlike STN-DBS, also produced significant amelioration of daytime sleepiness. Our study suggests that PPTg-DBS plays an important role in reorganizing regular sleep in PD patients.

  12. Modulation of attentional processing by deep brain stimulation of the pedunculopontine nucleus region in patients with parkinsonian disorders.

    PubMed

    Fischer, Julia; Schwiecker, Kati; Bittner, Verena; Heinze, Hans-Jochen; Voges, Jürgen; Galazky, Imke; Zaehle, Tino

    2015-07-01

    Low-frequency electrical stimulation of the pedunculopontine nucleus (PPN) is a therapeutic approach aiming to improve motor symptoms such as freezing of gate and postural instability in parkinsonian disorders. Because the PPN is a component of the reticular activating system, we tested whether PPN stimulation directly affects attention and consciousness. Eight patients with parkinsonian disorders and implanted with electrodes in the bilateral PPN underwent computerized assessment of attention. Performance in 3 standard reaction time (RT) tasks was assessed at 5 different stimulation frequencies in 5 consecutive sessions. Stimulation of the PPN at low (8 Hz) and therapeutic (20 Hz) frequencies led to a significant improvement of performance in a simple RT task. Patients' RTs were significantly faster at stimulation frequencies of 8 Hz and 20 Hz relative to no stimulation. Stimulation did not affect patients' performance in more complex attentional tasks. Low-frequent stimulation of PPN improves basal attentional processing in patients with parkinsonian disorders, leading to an improved tonic alertness. As successful performance in this task requires the intrinsic ability to build up and keep a certain level of attention, this might be interpreted as attentional augmentation related to stimulation features. Stimulation had no effect on more complex attentional processing. Our results suggest an influence of the PPN on certain aspects of attention, supporting attentional augmentation as one possible mechanism to improve motor action and gait in patients with parkinsonian disorders. (c) 2015 APA, all rights reserved).

  13. Outcomes from stimulation of the caudal zona incerta and pedunculopontine nucleus in patients with Parkinson's disease.

    PubMed

    Khan, Sadaquate; Mooney, Lucy; Plaha, Puneet; Javed, Shazia; White, Paul; Whone, Alan L; Gill, Steven S

    2011-04-01

    Axial symptoms including postural instability, falls and failure of gait initiation are some of the most disabling motor symptoms of Parkinson's disease (PD). We performed bilateral deep brain stimulation (DBS) of the pedunculopontine nucleus (PPN) in combination with the caudal zona incerta (cZi) in order to determine their efficacy in alleviating these symptoms. Seven patients with predominant axial symptoms in both the 'on' and 'off' medication states underwent bilateral cZi and PPN DBS. Motor outcomes were assessed using the motor component of the Unified Parkinson's Disease Rating Scale (UPDRS 3) and a composite axial subscore was derived from items 27, 28, 29 and 30 (arising from chair, posture, gait and postural stability). Quality of life was measured using the PDQ39. Comparisons were made between scores obtained at baseline and those at a mean follow-up of 12 months. In both the off and on medication states, a statistically significant improvement in the UPDRS part 3 score was achieved by stimulation of the PPN, cZi and both in combination. In the off medication state, our composite axial subscore of the UPDRS part 3 improved with stimulation of the PPN, cZi and both in combination. The composite axial subscore, in the 'on' medication state, however, only showed a statistically significant improvement when a combination of cZi and PPN stimulation was used. This study provides evidence that a combination of PPN and cZi stimulation can achieve a significant improvement in the hitherto untreatable 'on' medication axial symptoms of PD.

  14. Neurophysiology of the pedunculopontine tegmental nucleus.

    PubMed

    Vitale, F; Capozzo, A; Mazzone, P; Scarnati, E

    2018-03-07

    The interest in the pedunculopontine tegmental nucleus (PPTg), a structure located in the brainstem at the level of the pontomesencephalic junction, has greatly increased in recent years because it is involved in the regulation of physiological functions that fail in Parkinson's disease and because it is a promising target for deep brain stimulation in movement disorders. The PPTg is highly interconnected with the main basal ganglia nuclei and relays basal ganglia activity to thalamic and brainstem nuclei and to spinal effectors. In this review, we address the functional role of the main PPTg outputs directed to the basal ganglia, thalamus, cerebellum and spinal cord. Together, the data that we discuss show that the PPTg may influence thalamocortical activity and spinal motoneuron excitability through its ascending and descending output fibers, respectively. Cerebellar nuclei may also relay signals from the PPTg to thalamic and brainstem nuclei. In addition to participating in motor functions, the PPTg participates in arousal, attention, action selection and reward mechanisms. Finally, we discuss the possibility that the PPTg may be involved in excitotoxic degeneration of the dopaminergic neurons of the substantia nigra through the glutamatergic monosynaptic input that it provides to these neurons. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. [The pedunculopontine nucleus. A structure involved in motor and emotional processing].

    PubMed

    Blanco-Lezcano, L; Pavón-Fuentes, N; Serrano-Sánchez, T; Blanco-Lezcano, V; Coro-Grave de Peralta, Y; Joseph-Bouza, Y

    There is currently a growing interest for conducting studies into the electrical and neurochemical activity of the pedunculopontine nucleus (PPN) due to the privileged position occupied by this structure in the flow of information to and from the cortex. This nucleus acts as a relay, not only for the motor information that is processed in the basal ganglia but also for information of an emotional type, whose main centre is the nucleus accumbens. It is also strongly linked with the aspects that determine the mechanisms governing addiction to certain drugs. We conduct a detailed analysis of the main findings from studies of the role played by the PPN in the physiopathology of Parkinsonism, namely the study of metabolic activity, immunohistochemical studies with different tracers, electrophysiological studies that have confirmed the immunohistochemical observations, as well as deep electrical stimulation carried out in non human primates. Furthermore, we also examine the part played by this structure in the processing of emotional information associated with different learning tasks. Overall, the authors grant the PPN a privileged position in the physiopathology of the axial disorders related to Parkinson s disease; its most important afference, stemming from the subthalamic nucleus, appears to play a key role in the understanding of the part played by the PPN in Parkinsonism.

  16. A Review of the Pedunculopontine Nucleus in Parkinson's Disease.

    PubMed

    French, Isobel T; Muthusamy, Kalai A

    2018-01-01

    The pedunculopontine nucleus (PPN) is situated in the upper pons in the dorsolateral portion of the ponto-mesencephalic tegmentum. Its main mass is positioned at the trochlear nucleus level, and is part of the mesenphalic locomotor region (MLR) in the upper brainstem. The human PPN is divided into two subnuclei, the pars compacta (PPNc) and pars dissipatus (PPNd), and constitutes both cholinergic and non-cholinergic neurons with afferent and efferent projections to the cerebral cortex, thalamus, basal ganglia (BG), cerebellum, and spinal cord. The BG controls locomotion and posture via GABAergic output of the substantia nigra pars reticulate (SNr). In PD patients, GABAergic BG output levels are abnormally increased, and gait disturbances are produced via abnormal increases in SNr-induced inhibition of the MLR. Since the PPN is vastly connected with the BG and the brainstem, dysfunction within these systems lead to advanced symptomatic progression in Parkinson's disease (PD), including sleep and cognitive issues. To date, the best treatment is to perform deep brain stimulation (DBS) on PD patients as outcomes have shown positive effects in ameliorating the debilitating symptoms of this disease by treating pathological circuitries within the parkinsonian brain. It is therefore important to address the challenges and develop this procedure to improve the quality of life of PD patients.

  17. A Review of the Pedunculopontine Nucleus in Parkinson's Disease

    PubMed Central

    French, Isobel T.; Muthusamy, Kalai A.

    2018-01-01

    The pedunculopontine nucleus (PPN) is situated in the upper pons in the dorsolateral portion of the ponto-mesencephalic tegmentum. Its main mass is positioned at the trochlear nucleus level, and is part of the mesenphalic locomotor region (MLR) in the upper brainstem. The human PPN is divided into two subnuclei, the pars compacta (PPNc) and pars dissipatus (PPNd), and constitutes both cholinergic and non-cholinergic neurons with afferent and efferent projections to the cerebral cortex, thalamus, basal ganglia (BG), cerebellum, and spinal cord. The BG controls locomotion and posture via GABAergic output of the substantia nigra pars reticulate (SNr). In PD patients, GABAergic BG output levels are abnormally increased, and gait disturbances are produced via abnormal increases in SNr-induced inhibition of the MLR. Since the PPN is vastly connected with the BG and the brainstem, dysfunction within these systems lead to advanced symptomatic progression in Parkinson's disease (PD), including sleep and cognitive issues. To date, the best treatment is to perform deep brain stimulation (DBS) on PD patients as outcomes have shown positive effects in ameliorating the debilitating symptoms of this disease by treating pathological circuitries within the parkinsonian brain. It is therefore important to address the challenges and develop this procedure to improve the quality of life of PD patients. PMID:29755338

  18. Activation of Pedunculopontine Glutamate Neurons Is Reinforcing

    PubMed Central

    Yoo, Ji Hoon; Zell, Vivien; Wu, Johnathan; Punta, Cindy; Ramajayam, Nivedita; Shen, Xinyi; Faget, Lauren; Lilascharoen, Varoth; Lim, Byung Kook

    2017-01-01

    Dopamine transmission from midbrain ventral tegmental area (VTA) neurons underlies behavioral processes related to motivation and drug addiction. The pedunculopontine tegmental nucleus (PPTg) is a brainstem nucleus containing glutamate-, acetylcholine-, and GABA-releasing neurons with connections to basal ganglia and limbic brain regions. Here we investigated the role of PPTg glutamate neurons in reinforcement, with an emphasis on their projections to VTA dopamine neurons. We used cell-type-specific anterograde tracing and optogenetic methods to selectively label and manipulate glutamate projections from PPTg neurons in mice. We used anatomical, electrophysiological, and behavioral assays to determine their patterns of connectivity and ascribe functional roles in reinforcement. We found that photoactivation of PPTg glutamate cell bodies could serve as a direct positive reinforcer on intracranial self-photostimulation assays. Further, PPTg glutamate neurons directly innervate VTA; photostimulation of this pathway preferentially excites VTA dopamine neurons and is sufficient to induce behavioral reinforcement. These results demonstrate that ascending PPTg glutamate projections can drive motivated behavior, and PPTg to VTA synapses may represent an important target relevant to drug addiction and other mental health disorders. SIGNIFICANCE STATEMENT Uncovering brain circuits underlying reward-seeking is an important step toward understanding the circuit bases of drug addiction and other psychiatric disorders. The dopaminergic system emanating from the ventral tegmental area (VTA) plays a key role in regulating reward-seeking behaviors. We used optogenetics to demonstrate that the pedunculopontine tegmental nucleus sends glutamatergic projections to VTA dopamine neurons, and that stimulation of this circuit promotes behavioral reinforcement. The findings support a critical role for pedunculopontine tegmental nucleus glutamate neurotransmission in modulating VTA dopamine

  19. Cholinergic, Glutamatergic, and GABAergic Neurons of the Pedunculopontine Tegmental Nucleus Have Distinct Effects on Sleep/Wake Behavior in Mice

    PubMed Central

    Kroeger, Daniel; Ferrari, Loris L.; Mahoney, Carrie E.; Arrigoni, Elda

    2017-01-01

    The pedunculopontine tegmental (PPT) nucleus has long been implicated in the regulation of cortical activity and behavioral states, including rapid eye-movement (REM) sleep. For example, electrical stimulation of the PPT region during sleep leads to rapid awakening, whereas lesions of the PPT in cats reduce REM sleep. Though these effects have been linked with the activity of cholinergic PPT neurons, the PPT also includes intermingled glutamatergic and GABAergic cell populations, and the precise roles of cholinergic, glutamatergic, and GABAergic PPT cell groups in regulating cortical activity and behavioral state remain unknown. Using a chemogenetic approach in three Cre-driver mouse lines, we found that selective activation of glutamatergic PPT neurons induced prolonged cortical activation and behavioral wakefulness, whereas inhibition reduced wakefulness and increased non-REM (NREM) sleep. Activation of cholinergic PPT neurons suppressed lower-frequency electroencephalogram rhythms during NREM sleep. Last, activation of GABAergic PPT neurons slightly reduced REM sleep. These findings reveal that glutamatergic, cholinergic, and GABAergic PPT neurons differentially influence cortical activity and sleep/wake states. SIGNIFICANCE STATEMENT More than 40 million Americans suffer from chronic sleep disruption, and the development of effective treatments requires a more detailed understanding of the neuronal mechanisms controlling sleep and arousal. The pedunculopontine tegmental (PPT) nucleus has long been considered a key site for regulating wakefulness and REM sleep. This is mainly because of the cholinergic neurons contained in the PPT nucleus. However, the PPT nucleus also contains glutamatergic and GABAergic neurons that likely contribute to the regulation of cortical activity and sleep–wake states. The chemogenetic experiments in the present study reveal that cholinergic, glutamatergic, and GABAergic PPT neurons each have distinct effects on sleep/wake behavior

  20. Cholinergic, Glutamatergic, and GABAergic Neurons of the Pedunculopontine Tegmental Nucleus Have Distinct Effects on Sleep/Wake Behavior in Mice.

    PubMed

    Kroeger, Daniel; Ferrari, Loris L; Petit, Gaetan; Mahoney, Carrie E; Fuller, Patrick M; Arrigoni, Elda; Scammell, Thomas E

    2017-02-01

    The pedunculopontine tegmental (PPT) nucleus has long been implicated in the regulation of cortical activity and behavioral states, including rapid eye-movement (REM) sleep. For example, electrical stimulation of the PPT region during sleep leads to rapid awakening, whereas lesions of the PPT in cats reduce REM sleep. Though these effects have been linked with the activity of cholinergic PPT neurons, the PPT also includes intermingled glutamatergic and GABAergic cell populations, and the precise roles of cholinergic, glutamatergic, and GABAergic PPT cell groups in regulating cortical activity and behavioral state remain unknown. Using a chemogenetic approach in three Cre-driver mouse lines, we found that selective activation of glutamatergic PPT neurons induced prolonged cortical activation and behavioral wakefulness, whereas inhibition reduced wakefulness and increased non-REM (NREM) sleep. Activation of cholinergic PPT neurons suppressed lower-frequency electroencephalogram rhythms during NREM sleep. Last, activation of GABAergic PPT neurons slightly reduced REM sleep. These findings reveal that glutamatergic, cholinergic, and GABAergic PPT neurons differentially influence cortical activity and sleep/wake states. More than 40 million Americans suffer from chronic sleep disruption, and the development of effective treatments requires a more detailed understanding of the neuronal mechanisms controlling sleep and arousal. The pedunculopontine tegmental (PPT) nucleus has long been considered a key site for regulating wakefulness and REM sleep. This is mainly because of the cholinergic neurons contained in the PPT nucleus. However, the PPT nucleus also contains glutamatergic and GABAergic neurons that likely contribute to the regulation of cortical activity and sleep-wake states. The chemogenetic experiments in the present study reveal that cholinergic, glutamatergic, and GABAergic PPT neurons each have distinct effects on sleep/wake behavior, improving our

  1. Asymmetric pedunculopontine network connectivity in parkinsonian patients with freezing of gait

    PubMed Central

    Fling, Brett W.; Cohen, Rajal G.; Mancini, Martina; Nutt, John G.; Fair, Damian A.

    2013-01-01

    Freezing of gait is one of the most debilitating symptoms in Parkinson’s disease as it causes falls and reduces mobility and quality of life. The pedunculopontine nucleus is one of the major nuclei of the mesencephalic locomotor region and has neurons related to anticipatory postural adjustments preceding step initiation as well as to the step itself, thus it may be critical for coupling posture and gait to avoid freezing. Because freezing of gait and postural impairments have been related to frontal lesions and frontal dysfunction such as executive function, we hypothesized that freezing is associated with disrupted connectivity between midbrain locomotor regions and medial frontal cortex. We used diffusion tensor imaging to quantify structural connectivity of the pedunculopontine nucleus in patients with Parkinson’s disease with freezing of gait, without freezing, and healthy age-matched controls. We also included behavioural tasks to gauge severity of freezing of gait, quantify gait metrics, and assess executive cognitive functions to determine whether between-group differences in executive dysfunction were related to pedunculopontine nucleus structural network connectivity. Using seed regions from the pedunculopontine nucleus, we were able to delineate white matter connections between the spinal cord, cerebellum, pedunculopontine nucleus, subcortical and frontal/prefrontal cortical regions. The current study is the first to demonstrate differences in structural connectivity of the identified locomotor pathway in patients with freezing of gait. We report reduced connectivity of the pedunculopontine nucleus with the cerebellum, thalamus and multiple regions of the frontal cortex. Moreover, these structural differences were observed solely in the right hemisphere of patients with freezing of gait. Finally, we show that the more left hemisphere-lateralized the pedunculopontine nucleus tract volume, the poorer the performance on cognitive tasks requiring the

  2. Pedunculopontine Nucleus Region Deep Brain Stimulation in Parkinson Disease: Surgical Techniques, Side Effects, and Postoperative Imaging

    PubMed Central

    Hamani, Clement; Lozano, Andres M.; Mazzone, Paolo A.M.; Moro, Elena; Hutchison, William; Silburn, Peter A.; Zrinzo, Ludvic; Alam, Mesbah; Goetz, Laurent; Pereira, Erlick; Rughani, Anand; Thevathasan, Wesley; Aziz, Tipu; Bloem, Bastiaan R.; Brown, Peter; Chabardes, Stephan; Coyne, Terry; Foote, Kelly; Garcia-Rill, Edgar; Hirsch, Etienne C.; Okun, Michael S.; Krauss, Joachim K.

    2017-01-01

    The pedunculopontine nucleus (PPN) region has received considerable attention in clinical studies as a target for deep brain stimulation (DBS) in Parkinson disease. These studies have yielded variable results with an overall impression of improvement in falls and freezing in many but not all patients treated. We evaluated the available data on the surgical anatomy and terminology of the PPN region in a companion paper. Here we focus on issues concerning surgical technique, imaging, and early side effects of surgery. The aim of this paper was to gain more insight into the reasoning for choosing specific techniques and to discuss short-comings of available studies. Our data demonstrate the wide range in almost all fields which were investigated. There are a number of important challenges to be resolved, such as identification of the optimal target, the choice of the surgical approach to optimize electrode placement, the impact on the outcome of specific surgical techniques, the reliability of intraoperative confirmation of the target, and methodological differences in postoperative validation of the electrode position. There is considerable variability both within and across groups, the overall experience with PPN DBS is still limited, and there is a lack of controlled trials. Despite these challenges, the procedure seems to provide benefit to selected patients and appears to be relatively safe. One important limitation in comparing studies from different centers and analyzing outcomes is the great variability in targeting and surgical techniques, as shown in our paper. The challenges we identified will be of relevance when designing future studies to better address several controversial issues. We hope that the data we accumulated may facilitate the development of surgical protocols for PPN DBS. PMID:27728909

  3. The pedunculopontine tegmental nucleus: from basic neuroscience to neurosurgical applications

    PubMed Central

    Simon, Christen; Smith, Kristen; Kezunovic, Nebosja; Hyde, James

    2011-01-01

    One element of the reticular activating system (RAS) is the pedunculopontine nucleus (PPN), which projects to the thalamus to trigger thalamocortical rhythms and the brainstem to modulate muscle tone and locomotion. The PPN is a posterior midbrain site known to induce locomotion in decerebrate animals when activated at 40–60 Hz, and has become a target for DBS in disorders involving gait deficits. We developed a research program using brainstem slices containing the PPN to study the cellular and molecular organization of this region. We showed that PPN neurons preferentially fire at gamma band frequency (30–60 Hz) when maximally activated, accounting for the effects of electrical stimulation. In addition, we developed the P13 midlatency auditory evoked potential, which is generated by PPN outputs, in freely moving rats. This allows the study of PPN cellular and molecular mechanisms in the whole animal. We also study the P50 midlatency auditory evoked potential, which is the human equivalent of the rodent P13 potential, allowing us to study PPN-related processes detected in vitro, confirmed in the whole animal, and tested in humans. Previous findings on the P50 potential in PD suggest that PPN output in this disorder is overactive. This translational research program led to the discovery of a novel mechanism of sleep–wake control based on electrical coupling, pointing the way to a number of new clinical applications in the development of novel stimulants (e.g., modafinil) and anesthetics. In addition, it provides methods for monitoring therapeutic efficacy of DBS in humans and animal models. PMID:20936418

  4. Implications of gamma band activity in the pedunculopontine nucleus

    PubMed Central

    Garcia-Rill, E.; Luster, B.; D’Onofrio, S.; Mahaffey, S.; Bisagno, V.; Urbano, F. J.

    2015-01-01

    The fact that the pedunculopontine nucleus (PPN) is part of the reticular activating system places it in a unique position to modulate sensory input and fight-or-flight responses. Arousing stimuli simultaneously activate ascending projections of the PPN to the intralaminar thalamus to trigger cortical high frequency activity and arousal, as well as descending projections to reticulospinal systems to alter posture and locomotion. As such, the PPN has become a target for deep brain stimulation (DBS) for the treatment of Parkinson’s disease (PD), modulating gait, posture, and higher functions. This article describes the latest discoveries on PPN physiology and the role of the PPN in a number of disorders. It has now been determined that high frequency activity during waking and REM sleep is controlled by two different intracellular pathways and two calcium channels in PPN cells. Moreover, there are three different PPN cell types that have one or both calcium channels and may be active during waking only, REM sleep only, or both. Based on the new discoveries, novel mechanisms are proposed for insomnia as a waking disorder. In addition, neuronal calcium sensor protein-1 (NCS-1), which is over expressed in schizophrenia and bipolar disorder, may be responsible for the dysregulation in gamma band activity in at least some patients with these diseases. Recent results suggest that NCS-1 modulates PPN gamma band activity and that lithium acts to reduce the effects of over expressed NCS-1, accounting for its effectiveness in bipolar disorder. PMID:26597124

  5. Pharmacogenetic stimulation of cholinergic pedunculopontine neurons reverses motor deficits in a rat model of Parkinson's disease.

    PubMed

    Pienaar, Ilse S; Gartside, Sarah E; Sharma, Puneet; De Paola, Vincenzo; Gretenkord, Sabine; Withers, Dominic; Elson, Joanna L; Dexter, David T

    2015-09-23

    Patients with advanced Parkinson's disease (PD) often present with axial symptoms, including postural- and gait difficulties that respond poorly to dopaminergic agents. Although deep brain stimulation (DBS) of a highly heterogeneous brain structure, the pedunculopontine nucleus (PPN), improves such symptoms, the underlying neuronal substrate responsible for the clinical benefits remains largely unknown, thus hampering optimization of DBS interventions. Choline acetyltransferase (ChAT)::Cre(+) transgenic rats were sham-lesioned or rendered parkinsonian through intranigral, unihemispheric stereotaxic administration of the ubiquitin-proteasomal system inhibitor, lactacystin, combined with designer receptors exclusively activated by designer drugs (DREADD), to activate the cholinergic neurons of the nucleus tegmenti pedunculopontine (PPTg), the rat equivalent of the human PPN. We have previously shown that the lactacystin rat model accurately reflects aspects of PD, including a partial loss of PPTg cholinergic neurons, similar to what is seen in the post-mortem brains of advanced PD patients. In this manuscript, we show that transient activation of the remaining PPTg cholinergic neurons in the lactacystin rat model of PD, via peripheral administration of the cognate DREADD ligand, clozapine-N-oxide (CNO), dramatically improved motor symptoms, as was assessed by behavioral tests that measured postural instability, gait, sensorimotor integration, forelimb akinesia and general motor activity. In vivo electrophysiological recordings revealed increased spiking activity of PPTg putative cholinergic neurons during CNO-induced activation. c-Fos expression in DREADD overexpressed ChAT-immunopositive (ChAT+) neurons of the PPTg was also increased by CNO administration, consistent with upregulated neuronal activation in this defined neuronal population. Overall, these findings provide evidence that functional modulation of PPN cholinergic neurons alleviates parkinsonian motor

  6. Magnetic resonance diffusion tensor imaging for the pedunculopontine nucleus: proof of concept and histological correlation.

    PubMed

    Alho, A T D L; Hamani, C; Alho, E J L; da Silva, R E; Santos, G A B; Neves, R C; Carreira, L L; Araújo, C M M; Magalhães, G; Coelho, D B; Alegro, M C; Martin, M G M; Grinberg, L T; Pasqualucci, C A; Heinsen, H; Fonoff, E T; Amaro, E

    2017-08-01

    The pedunculopontine nucleus (PPN) has been proposed as target for deep brain stimulation (DBS) in patients with postural instability and gait disorders due to its involvement in muscle tonus adjustments and control of locomotion. However, it is a deep-seated brainstem nucleus without clear imaging or electrophysiological markers. Some studies suggested that diffusion tensor imaging (DTI) may help guiding electrode placement in the PPN by showing the surrounding fiber bundles, but none have provided a direct histological correlation. We investigated DTI fractional anisotropy (FA) maps from in vivo and in situ post-mortem magnetic resonance images (MRI) compared to histological evaluations for improving PPN targeting in humans. A post-mortem brain was scanned in a clinical 3T MR system in situ. Thereafter, the brain was processed with a special method ideally suited for cytoarchitectonic analyses. Also, nine volunteers had in vivo brain scanning using the same MRI protocol. Images from volunteers were compared to those obtained in the post-mortem study. FA values of the volunteers were obtained from PPN, inferior colliculus, cerebellar crossing fibers and medial lemniscus using histological data and atlas information. FA values in the PPN were significantly lower than in the surrounding white matter region and higher than in areas with predominantly gray matter. In Nissl-stained histologic sections, the PPN extended for more than 10 mm in the rostro-caudal axis being closely attached to the lateral parabrachial nucleus. Our DTI analyses and the spatial correlation with histological findings proposed a location for PPN that matched the position assigned to this nucleus in the literature. Coregistration of neuroimaging and cytoarchitectonic features can add value to help establishing functional architectonics of the PPN and facilitate neurosurgical targeting of this extended nucleus.

  7. Deep Brain Stimulation of Pedunculopontine Nucleus for Postural Instability and Gait Disorder After Parkinson Disease: A Meta-Analysis of Individual Patient Data.

    PubMed

    Wang, Jia-Wei; Zhang, Yu-Qing; Zhang, Xiao-Hua; Wang, Yun-Peng; Li, Ji-Ping; Li, Yong-Jie

    2017-06-01

    Postural instability and gait disorder (PIGD) in Parkinson disease (PD) has been a great challenge in clinical practice because PIGD is closely linked to major morbidity and mortality in PD. Pedunculopontine nucleus (PPN) has been considered as a potential promising target for deep brain stimulation (DBS) in the treatment of PIGD. A meta-analysis of individual patient data was performed to assess the effects of PPN DBS on PIGD in patients with PD and explore the factors predicting good outcome. According to the study strategy, we searched PubMed, Embase, and the Cochrane Central Register of Controlled Trials, and other sources. After searching the literature, 2 investigators independently screened the literature, assessed the quality of the included trials, and extracted the data. The outcome measures included PIGD, freezing of gait, and falling in PD. Then, individual patient data were incorporated into SPSS software for statistical analyses across series. Six studies reporting individual patient data were included for final analysis. PPN DBS significantly improved PIGD as well as freezing of gait and falling after PD, which was depending on the duration of follow-up and types of outcome measures. In addition, patient age, disease duration, levodopa-equivalent dosage, and the choice of unilateral or bilateral stimulation were similar in groups of patients with PD with or without improvement in PIGD after PPN DBS. Our study provides evidence that PPN DBS may improve PIGD, which should be interpreted with caution and needs further verification before making generalization of our results. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Cerebral blood flow changes induced by pedunculopontine nucleus stimulation in patients with advanced Parkinson's disease: a [(15)O] H2O PET study.

    PubMed

    Ballanger, Benedicte; Lozano, Andres M; Moro, Elena; van Eimeren, Thilo; Hamani, Clement; Chen, Robert; Cilia, Roberto; Houle, Sylvain; Poon, Yu Yan; Lang, Anthony E; Strafella, Antonio P

    2009-12-01

    Patients with advanced Parkinson's disease (PD) develop disabling axial symptoms, including gait disturbances, freezing and postural instability poorly responsive to levodopa replacement therapy. The pedunculopontine nucleus (PPN) is involved in locomotion, control of posture, and behavioral states [i.e. wakefulness, rapid eye movement sleep]. Recent reports suggested that PPN modulation with deep brain stimulation (DBS) may be beneficial in the treatment of axial symptoms. However, the mechanisms underlying these effects are still unknown. We used [(15)O] H(2)O PET to investigate regional cerebral blood flow in three patients with advanced PD who underwent a new experimental surgical procedure with implantation of unilateral PPN-DBS. Patients were studied Off-medication with stimulator Off and On, both at rest and during a self-paced alternating motor task of the lower limbs. We used SPM2 for imaging data analysis, threshold P < 0.05 corrected at the cluster level. Stimulation induced significant regional cerebral blood flow increment in subcortical regions such as the thalamus (P < 0.006), cerebellum (P < 0.001), and midbrain region (P < 0.001) as well as different cortical areas involving medial sensorimotor cortex extending into caudal supplementary motor area (BA 4/6; P < 0.001). PPN-DBS in advanced PD resulted in blood flow and presumably neuronal activity changes in subcortical and cortical areas involved in balance and motor control, including the mesencephalic locomotor region (e.g. PPN) and closely interconnected structures within the cerebello-(rubro)-thalamo-cortical circuit. Whether these findings are associated with the DBS-PPN clinical effect remains to be proven. However, they suggest that PPN modulation may induce functional changes in neural networks associated with the control of lower limb movements. 2009 Wiley-Liss, Inc.

  9. Role of the pedunculopontine nucleus in controlling gait and sleep in normal and parkinsonian monkeys.

    PubMed

    Karachi, C; Francois, Chantal

    2018-03-01

    Patients with Parkinson's disease (PD) develop cardinal motor symptoms, including akinesia, rigidity, and tremor, that are alleviated by dopaminergic medication and/or subthalamic deep brain stimulation. Over the time course of the disease, gait and balance disorders worsen and become resistant to pharmacological and surgical treatments. These disorders generate debilitating motor symptoms leading to increased dependency, morbidity, and mortality. PD patients also experience sleep disturbance that raise the question of a common physiological basis. An extensive experimental and clinical body of work has highlighted the crucial role of the pedunculopontine nucleus (PPN) in the control of gait and sleep, and its potential major role in PD. Here, we summarise our investigations in the monkey PPN in the normal and parkinsonian states. We first examined the anatomy and connectivity of the PPN and the cuneiform nucleus which both belong to the mesencephalic locomotor region. Second, we conducted experiments to demonstrate the specific effects of PPN cholinergic lesions on locomotion in the normal and parkinsonian monkey. Third, we aimed to understand how PPN cholinergic lesions impair sleep in parkinsonian monkeys. Our final goal was to develop a novel model of advanced PD with gait and sleep disorders. We believe that this monkey model, even if it does not attempt to reproduce the exact human disease with all its complexities, represents a good biomedical model to characterise locomotion and sleep in the context of PD.

  10. Pedunculopontine network dysfunction in Parkinson's disease with postural control and sleep disorders.

    PubMed

    Gallea, Cecile; Ewenczyk, Claire; Degos, Bertrand; Welter, Marie-Laure; Grabli, David; Leu-Semenescu, Smaranda; Valabregue, Romain; Berroir, Pierre; Yahia-Cherif, Lydia; Bertasi, Eric; Fernandez-Vidal, Sara; Bardinet, Eric; Roze, Emmanuel; Benali, Habib; Poupon, Cyril; François, Chantal; Arnulf, Isabelle; Lehéricy, Stéphane; Vidailhet, Marie

    2017-05-01

    The objective of this study was to investigate pedunculopontine nucleus network dysfunctions that mediate impaired postural control and sleep disorder in Parkinson's disease. We examined (1) Parkinson's disease patients with impaired postural control and rapid eye movement sleep behavior disorder (further abbreviated as sleep disorder), (2) Parkinson's disease patients with sleep disorder only, (3) Parkinson's disease patients with neither impaired postural control nor sleep disorder, and (4) healthy volunteers. We assessed postural control with clinical scores and biomechanical recordings during gait initiation. Participants had video polysomnography, daytime sleepiness self-evaluation, and resting-state functional MRIs. Patients with impaired postural control and sleep disorder had longer duration of anticipatory postural adjustments during gait initiation and decreased functional connectivity between the pedunculopontine nucleus and the supplementary motor area in the locomotor network that correlated negatively with the duration of anticipatory postural adjustments. Both groups of patients with sleep disorder had decreased functional connectivity between the pedunculopontine nucleus and the anterior cingulate cortex in the arousal network that correlated with daytime sleepiness. The degree of dysfunction in the arousal network was related to the degree of connectivity in the locomotor network in all patients with sleep disorder, but not in patients without sleep disorder or healthy volunteers. These results shed light on the functional neuroanatomy of pedunculopontine nucleus networks supporting the clinical manifestation and the interdependence between sleep and postural control impairments in Parkinson's disease. © 2016 International Parkinson and Movement Disorder Society. © 2017 International Parkinson and Movement Disorder Society.

  11. Pedunculopontine Nucleus Gamma Band Activity-Preconscious Awareness, Waking, and REM Sleep

    PubMed Central

    Urbano, Francisco J.; D’Onofrio, Stasia M.; Luster, Brennon R.; Beck, Paige B.; Hyde, James Robert; Bisagno, Veronica; Garcia-Rill, Edgar

    2014-01-01

    The pedunculopontine nucleus (PPN) is a major component of the reticular activating system (RAS) that regulates waking and REM sleep, states of high-frequency EEG activity. Recently, we described the presence of high threshold, voltage-dependent N- and P/Q-type calcium channels in RAS nuclei that subserve gamma band oscillations in the mesopontine PPN, intralaminar parafascicular nucleus (Pf), and pontine subcoeruleus nucleus dorsalis (SubCD). Cortical gamma band activity participates in sensory perception, problem solving, and memory. Rather than participating in the temporal binding of sensory events as in the cortex, gamma band activity in the RAS may participate in the processes of preconscious awareness, and provide the essential stream of information for the formulation of many of our actions. That is, the RAS may play an early permissive role in volition. Our latest results suggest that (1) the manifestation of gamma band activity during waking may employ a separate intracellular pathway compared to that during REM sleep, (2) neuronal calcium sensor (NCS-1) protein, which is over expressed in schizophrenia and bipolar disorder, modulates gamma band oscillations in the PPN in a concentration-dependent manner, (3) leptin, which undergoes resistance in obesity resulting in sleep dysregulation, decreases sodium currents in PPN neurons, accounting for its normal attenuation of waking, and (4) following our discovery of electrical coupling in the RAS, we hypothesize that there are cell clusters within the PPN that may act in concert. These results provide novel information on the mechanisms controlling high-frequency activity related to waking and REM sleep by elements of the RAS. PMID:25368599

  12. Pedunculopontine Nucleus Gamma Band Activity-Preconscious Awareness, Waking, and REM Sleep.

    PubMed

    Urbano, Francisco J; D'Onofrio, Stasia M; Luster, Brennon R; Beck, Paige B; Hyde, James Robert; Bisagno, Veronica; Garcia-Rill, Edgar

    2014-01-01

    The pedunculopontine nucleus (PPN) is a major component of the reticular activating system (RAS) that regulates waking and REM sleep, states of high-frequency EEG activity. Recently, we described the presence of high threshold, voltage-dependent N- and P/Q-type calcium channels in RAS nuclei that subserve gamma band oscillations in the mesopontine PPN, intralaminar parafascicular nucleus (Pf), and pontine subcoeruleus nucleus dorsalis (SubCD). Cortical gamma band activity participates in sensory perception, problem solving, and memory. Rather than participating in the temporal binding of sensory events as in the cortex, gamma band activity in the RAS may participate in the processes of preconscious awareness, and provide the essential stream of information for the formulation of many of our actions. That is, the RAS may play an early permissive role in volition. Our latest results suggest that (1) the manifestation of gamma band activity during waking may employ a separate intracellular pathway compared to that during REM sleep, (2) neuronal calcium sensor (NCS-1) protein, which is over expressed in schizophrenia and bipolar disorder, modulates gamma band oscillations in the PPN in a concentration-dependent manner, (3) leptin, which undergoes resistance in obesity resulting in sleep dysregulation, decreases sodium currents in PPN neurons, accounting for its normal attenuation of waking, and (4) following our discovery of electrical coupling in the RAS, we hypothesize that there are cell clusters within the PPN that may act in concert. These results provide novel information on the mechanisms controlling high-frequency activity related to waking and REM sleep by elements of the RAS.

  13. Vestibular responses in the macaque pedunculopontine nucleus and central mesencephalic reticular formation

    PubMed Central

    Aravamuthan, Bhooma R.; Angelaki, Dora E.

    2012-01-01

    The pedunculopontine nucleus (PPN) and central mesencephalic reticular formation (cMRF) both send projections and receive input from areas with known vestibular responses. Noting their connections with the basal ganglia, the locomotor disturbances that occur following lesions of the PPN or cMRF, and the encouraging results of PPN deep brain stimulation in Parkinson’s disease patients, both the PPN and cMRF have been linked to motor control. In order to determine the existence of and characterize vestibular responses in the PPN and cMRF, we recorded single neurons from both structures during vertical and horizontal rotation, translation, and visual pursuit stimuli. The majority of PPN cells (72.5%) were vestibular-only cells that responded exclusively to rotation and translation stimuli but not visual pursuit. Visual pursuit responses were much more prevalent in the cMRF (57.1%) though close to half of cMRF cells were vestibular-only cells (41.1%). Directional preferences also differed between the PPN, which was preferentially modulated during nose-down pitch, and cMRF, which was preferentially modulated during ipsilateral yaw rotation. Finally, amplitude responses were similar between the PPN and cMRF during rotation and pursuit stimuli, but PPN responses to translation were of higher amplitude than cMRF responses. Taken together with their connections to the vestibular circuit, these results implicate the PPN and cMRF in the processing of vestibular stimuli and suggest important roles for both in responding to motion perturbations like falls and turns. PMID:22864184

  14. Vestibular responses in the macaque pedunculopontine nucleus and central mesencephalic reticular formation.

    PubMed

    Aravamuthan, B R; Angelaki, D E

    2012-10-25

    The pedunculopontine nucleus (PPN) and central mesencephalic reticular formation (cMRF) both send projections and receive input from areas with known vestibular responses. Noting their connections with the basal ganglia, the locomotor disturbances that occur following lesions of the PPN or cMRF, and the encouraging results of PPN deep brain stimulation in Parkinson's disease patients, both the PPN and cMRF have been linked to motor control. In order to determine the existence of and characterize vestibular responses in the PPN and cMRF, we recorded single neurons from both structures during vertical and horizontal rotation, translation, and visual pursuit stimuli. The majority of PPN cells (72.5%) were vestibular-only (VO) cells that responded exclusively to rotation and translation stimuli but not visual pursuit. Visual pursuit responses were much more prevalent in the cMRF (57.1%) though close to half of cMRF cells were VO cells (41.1%). Directional preferences also differed between the PPN, which was preferentially modulated during nose-down pitch, and cMRF, which was preferentially modulated during ipsilateral yaw rotation. Finally, amplitude responses were similar between the PPN and cMRF during rotation and pursuit stimuli, but PPN responses to translation were of higher amplitude than cMRF responses. Taken together with their connections to the vestibular circuit, these results implicate the PPN and cMRF in the processing of vestibular stimuli and suggest important roles for both in responding to motion perturbations like falls and turns. Copyright © 2012 IBRO. Published by Elsevier Ltd. All rights reserved.

  15. The role of pedunculopontine nucleus in choice behavior under risk

    PubMed Central

    Leblond, Mona; Sukharnikova, Tatyana; Yu, Chunxiu; Rossi, Mark A.; Yin, Henry H.

    2014-01-01

    The dopaminergic projections to the basal ganglia have long been implicated in reward guided behavior and decision making, yet little is known about the role of the posterior pedunculopontine nucleus (pPPN), a major source of excitatory input to the mesolimbic dopamine system. Here we studied the contributions of pPPN to decision making under risk, using excitoxic lesions and reversible inactivation in rats. Rats could choose between two options: a small but certain reward on one lever, or a large but uncertain reward on the other lever. The overall payoff associated with each choice is the same, but the reward variance (risk) associated with the risky choice is much higher. In Experiment 1, we showed that excitotoxic lesions of the pPPN before training did not affect acquisition of lever pressing. But whereas the controls strongly preferred the safe choice, the lesioned rats did not. In Experiment 2, we found that muscimol inactivation of the pPPN also reversibly altered choice behavior. These results show that permanent lesions or reversible inactivation of the pPPN both abolish risk aversion in decision making. PMID:24617747

  16. Pedunculopontine tegmental nucleus lesions impair stimulus--reward learning in autoshaping and conditioned reinforcement paradigms.

    PubMed

    Inglis, W L; Olmstead, M C; Robbins, T W

    2000-04-01

    The role of the pedunculopontine tegmental nucleus (PPTg) in stimulus-reward learning was assessed by testing the effects of PPTg lesions on performance in visual autoshaping and conditioned reinforcement (CRf) paradigms. Rats with PPTg lesions were unable to learn an association between a conditioned stimulus (CS) and a primary reward in either paradigm. In the autoshaping experiment, PPTg-lesioned rats approached the CS+ and CS- with equal frequency, and the latencies to respond to the two stimuli did not differ. PPTg lesions also disrupted discriminated approaches to an appetitive CS in the CRf paradigm and completely abolished the acquisition of responding with CRf. These data are discussed in the context of a possible cognitive function of the PPTg, particularly in terms of lesion-induced disruptions of attentional processes that are mediated by the thalamus.

  17. Neural Correlates of the Antinociceptive Effects of Stimulating the Anterior Pretectal Nucleus in Rats.

    PubMed

    Genaro, Karina; Prado, Wiliam A

    2016-11-01

    Stimulation-evoked antinociception (SEA) from the anterior pretectal nucleus (APtN) activates mechanisms that descend to the spinal cord through the dorsolateral funiculus, but the encephalic route followed by the descending pathways from the APtN is not completely known. This study evaluated the changes in the SEA from the APtN in the Wistar rat tail-flick test after lidocaine-induced neural block or N-methyl-d-aspartate-induced neurotoxic lesion of the deep mesencephalic nucleus (DpMe), tegmental pedunculopontine nucleus (PPTg), or lateral paragigantocellular nucleus (LPGi). The SEA from the APtN was less intense after neural block of the contralateral DpMe or PPTg or the ipsilateral LPGi, but was not changed by the neural block of the ipsilateral DpMe or PPTg or the contralateral LPGi. Antinociception did not occur when APtN stimulation was carried out 5 minutes after lidocaine or 6 days after N-methyl-d-aspartate injections into the contralateral DpMe and the ipsilateral LPGi, or into the contralateral PPTg and the ipsilateral LPGi. We conclude that the SEA from the APtN activates 2 descending pain inhibitory pathways, one relaying in the ipsilateral LPGi and another relaying sequentially in the contralateral DpMe and PPTg. The antinociceptive effect of the APtN stimulation involves 2 descending pathways: one relaying in the ipsilateral LPGi and another descending contralaterally via relays in the DpMe and PPTg. Copyright © 2016 American Pain Society. Published by Elsevier Inc. All rights reserved.

  18. Decoding brain state transitions in the pedunculopontine nucleus: cooperative phasic and tonic mechanisms

    PubMed Central

    Petzold, Anne; Valencia, Miguel; Pál, Balázs; Mena-Segovia, Juan

    2015-01-01

    Cholinergic neurons of the pedunculopontine nucleus (PPN) are most active during the waking state. Their activation is deemed to cause a switch in the global brain activity from sleep to wakefulness, while their sustained discharge may contribute to upholding the waking state and enhancing arousal. Similarly, non-cholinergic PPN neurons are responsive to brain state transitions and their activation may influence some of the same targets of cholinergic neurons, suggesting that they operate in coordination. Yet, it is not clear how the discharge of distinct classes of PPN neurons organize during brain states. Here, we monitored the in vivo network activity of PPN neurons in the anesthetized rat across two distinct levels of cortical dynamics and their transitions. We identified a highly structured configuration in PPN network activity during slow-wave activity that was replaced by decorrelated activity during the activated state (AS). During the transition, neurons were predominantly excited (phasically or tonically), but some were inhibited. Identified cholinergic neurons displayed phasic and short latency responses to sensory stimulation, whereas the majority of non-cholinergic showed tonic responses and remained at high discharge rates beyond the state transition. In vitro recordings demonstrate that cholinergic neurons exhibit fast adaptation that prevents them from discharging at high rates over prolonged time periods. Our data shows that PPN neurons have distinct but complementary roles during brain state transitions, where cholinergic neurons provide a fast and transient response to sensory events that drive state transitions, whereas non-cholinergic neurons maintain an elevated firing rate during global activation. PMID:26582977

  19. Efficacy and Safety of Pedunculopontine Nuclei (PPN) Deep Brain Stimulation in the Treatment of Gait Disorders: A Meta-Analysis of Clinical Studies.

    PubMed

    Golestanirad, Laleh; Elahi, Behzad; Graham, Simon J; Das, Sunit; Wald, Lawrence L

    2016-01-01

    Pedunculopontine nucleus (PPN) has complex reciprocal connections with basal ganglia, especially with internal globus pallidus and substantia nigra, and it has been postulated that PPN stimulation may improve gait instability and freezing of gait. In this meta-analysis, we will assess the evidence for PPN deep brain stimulation in treatment of gait and motor abnormalities especially focusing on Parkinson disease patients. PubMed and Scopus electronic databases were searched for related studies published before February 2014. Medline (1966-2014), Embase (1974-2010), CINAHL, Web of Science, Scopus bibliographic, and Google Scholar databases (1960-2014) were also searched for studies investigating effect of PPN deep brain stimulation in treatment of postural and postural instability and total of ten studies met the inclusion criteria for this analysis. Our findings showed a significant improvement in postural instability (p<0.001) and motor symptoms of Parkinson disease on and off medications (p<0.05), but failed to show improvement in freezing of gait. Despite significant improvement in postural instability observed in included studies, evidence from current literature is not sufficient to generalize these findings to the majority of patients.

  20. The Pedunculopontine Tegmental Nucleus as a Motor and Cognitive Interface between the Cerebellum and Basal Ganglia.

    PubMed

    Mori, Fumika; Okada, Ken-Ichi; Nomura, Taishin; Kobayashi, Yasushi

    2016-01-01

    As an important component of ascending activating systems, brainstem cholinergic neurons in the pedunculopontine tegmental nucleus (PPTg) are involved in the regulation of motor control (locomotion, posture and gaze) and cognitive processes (attention, learning and memory). The PPTg is highly interconnected with several regions of the basal ganglia, and one of its key functions is to regulate and relay activity from the basal ganglia. Together, they have been implicated in the motor control system (such as voluntary movement initiation or inhibition), and modulate aspects of executive function (such as motivation). In addition to its intimate connection with the basal ganglia, projections from the PPTg to the cerebellum have been recently reported to synaptically activate the deep cerebellar nuclei. Classically, the cerebellum and basal ganglia were regarded as forming separated anatomical loops that play a distinct functional role in motor and cognitive behavioral control. Here, we suggest that the PPTg may also act as an interface device between the basal ganglia and cerebellum. As such, part of the therapeutic effect of PPTg deep brain stimulation (DBS) to relieve gait freezing and postural instability in advanced Parkinson's disease (PD) patients might also involve modulation of the cerebellum. We review the anatomical position and role of the PPTg in the pathway of basal ganglia and cerebellum in relation to motor control, cognitive function and PD.

  1. The pedunculopontine tegmental nucleus: from basic neuroscience to neurosurgical applications: arousal from slices to humans: implications for DBS.

    PubMed

    Garcia-Rill, Edgar; Simon, Christen; Smith, Kristen; Kezunovic, Nebosja; Hyde, James

    2011-10-01

    One element of the reticular activating system (RAS) is the pedunculopontine nucleus (PPN), which projects to the thalamus to trigger thalamocortical rhythms and the brainstem to modulate muscle tone and locomotion. The PPN is a posterior midbrain site known to induce locomotion in decerebrate animals when activated at 40-60 Hz, and has become a target for DBS in disorders involving gait deficits. We developed a research program using brainstem slices containing the PPN to study the cellular and molecular organization of this region. We showed that PPN neurons preferentially fire at gamma band frequency (30-60 Hz) when maximally activated, accounting for the effects of electrical stimulation. In addition, we developed the P13 midlatency auditory evoked potential, which is generated by PPN outputs, in freely moving rats. This allows the study of PPN cellular and molecular mechanisms in the whole animal. We also study the P50 midlatency auditory evoked potential, which is the human equivalent of the rodent P13 potential, allowing us to study PPN-related processes detected in vitro, confirmed in the whole animal, and tested in humans. Previous findings on the P50 potential in PD suggest that PPN output in this disorder is overactive. This translational research program led to the discovery of a novel mechanism of sleep-wake control based on electrical coupling, pointing the way to a number of new clinical applications in the development of novel stimulants (e.g., modafinil) and anesthetics. In addition, it provides methods for monitoring therapeutic efficacy of DBS in humans and animal models.

  2. A Neural Correlate of Predicted and Actual Reward-Value Information in Monkey Pedunculopontine Tegmental and Dorsal Raphe Nucleus during Saccade Tasks

    PubMed Central

    Okada, Ken-ichi; Nakamura, Kae; Kobayashi, Yasushi

    2011-01-01

    Dopamine, acetylcholine, and serotonin, the main modulators of the central nervous system, have been proposed to play important roles in the execution of movement, control of several forms of attentional behavior, and reinforcement learning. While the response pattern of midbrain dopaminergic neurons and its specific role in reinforcement learning have been revealed, the role of the other neuromodulators remains rather elusive. Here, we review our recent studies using extracellular recording from neurons in the pedunculopontine tegmental nucleus, where many cholinergic neurons exist, and the dorsal raphe nucleus, where many serotonergic neurons exist, while monkeys performed eye movement tasks to obtain different reward values. The firing patterns of these neurons are often tonic throughout the task period, while dopaminergic neurons exhibited a phasic activity pattern to the task event. The different modulation patterns, together with the activity of dopaminergic neurons, reveal dynamic information processing between these different neuromodulator systems. PMID:22013541

  3. Neurotoxic lesions of the pedunculopontine tegmental nucleus impair the elaboration of postictal antinociception.

    PubMed

    de Oliveira, Rithiele Cristina; de Oliveira, Ricardo; Falconi-Sobrinho, Luiz Luciano; Biagioni, Audrey Franceschi; Almada, Rafael Carvalho; Dos Anjos-Garcia, Tayllon; Bazaglia-de-Sousa, Guilherme; Khan, Asmat Ullah; Coimbra, Norberto Cysne

    2018-05-12

    Generalised tonic-clonic seizures, generated by abnormal neuronal hyper-activity, cause a significant and long-lasting increase in the nociceptive threshold. The pedunculopontine tegmental nucleus (PPTN) plays a crucial role in the regulation of seizures as well as the modulation of pain, but its role in postictal antinociceptive processes remains unclear. In the present study, we aimed to investigate the involvement of PPTN neurons in the postictal antinociception. Wistar rats had their tail-flick baseline recorded and were injected with ibotenic acid (1.0 μg/0.2 μL) into the PPTN, aiming to promote a local neurotoxic lesion. Five days after the neuronal damage, pentylenetetrazole (PTZ; 64 mg/kg) was intraperitoneally administered to induce tonic-clonic seizures. The tail-withdrawal latency was measured immediately after the seizures (0 min) and subsequently at 10-min intervals until 130 min after the seizures were induced pharmacologically. Ibotenic acid microinjected into the PPTN did not reduce the PTZ-induced seizure duration and severity, but it diminished the postictal antinociception from 0 to 130 min after the end of the PTZ-induced tonic-clonic seizures. These results suggest that the postictal antinociception depends on the PPTN neuronal cells integrity. Copyright © 2018 Elsevier Inc. All rights reserved.

  4. Pedunculopontine Gamma Band Activity and Development.

    PubMed

    Garcia-Rill, Edgar; Luster, Brennon; Mahaffey, Susan; MacNicol, Melanie; Hyde, James R; D'Onofrio, Stasia M; Phillips, Cristy

    2015-12-03

    This review highlights the most important discovery in the reticular activating system in the last 10 years, the manifestation of gamma band activity in cells of the reticular activating system (RAS), especially in the pedunculopontine nucleus, which is in charge of waking and rapid eye movement (REM) sleep. The identification of different cell groups manifesting P/Q-type Ca(2+) channels that control waking vs. those that manifest N-type channels that control REM sleep provides novel avenues for the differential control of waking vs. REM sleep. Recent discoveries on the development of this system can help explain the developmental decrease in REM sleep and the basic rest-activity cycle.

  5. Pedunculopontine arousal system physiology – Implications for insomnia

    PubMed Central

    Garcia-Rill, Edgar; Luster, Brennon; Mahaffey, Susan; Bisagno, Veronica; Urbano, Francisco J.

    2015-01-01

    We consider insomnia a disorder of waking rather than a disorder of sleep. This review examines the role of the reticular activating system, especially the pedunculopontine nucleus, in the symptoms of insomnia, mainly representing an overactive waking drive. We determined that high frequency activity during waking and REM sleep is controlled by two different intracellular pathways and channel types in PPN cells. We found three different PPN cell types that have one or both channels and may be active during waking only, REM sleep only, or both. These discoveries point to a specific mechanism and novel therapeutic avenues for insomnia. PMID:26483950

  6. Intrinsic connections within the pedunculopontine tegmental nucleus are critical to the elaboration of post-ictal antinociception.

    PubMed

    Mazzei-Silva, Elaine Cristina; de Oliveira, Rithiele Cristina; dos Anjos Garcia, Tayllon; Falconi-Sobrinho, Luiz Luciano; Almada, Rafael Carvalho; Coimbra, Norberto Cysne

    2014-08-01

    This study investigated the intrinsic connections of a key-structure of the endogenous pain inhibitory system, the pedunculopontine tegmental nucleus (PPTN), in post-ictal antinociceptive process through synaptic inactivation of the PPTN with cobalt chloride. Male Wistar rats (n = 6 or 7 per group), weighing 250-280 g, had the tail-flick baseline recorded and were submitted to a stereotaxic surgery for the introduction of a guide-cannula aiming at the PPTN. After 5 days of postoperative recovery, cobalt chloride (1 mM/0.2 µL) or physiological saline (0.2 µL) were microinjected into the PPTN and after 5 min, the tail-withdrawal latency was measured again at 0, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, and 120 min after seizures evoked by intraperitoneal injection of pentylenetetrazole (64 mg/kg). The synaptic inactivation of PPTN decreased the post-ictal antinociceptive phenomenon, suggesting the involvement of PPTN intrinsic connections in the modulation of pain, during tonic-clonic seizures. These results showed that the PPTN may be crucially involved in the neural network that organizes the post-ictal analgesia. © 2014 Wiley Periodicals, Inc.

  7. Electrical coupling: novel mechanism for sleep-wake control.

    PubMed

    Garcia-Rill, Edgar; Heister, David S; Ye, Meijun; Charlesworth, Amanda; Hayar, Abdallah

    2007-11-01

    Recent evidence suggests that certain anesthetic agents decrease electrical coupling, whereas the stimulant modafinil appears to increase electrical coupling. We investigated the potential role of electrical coupling in 2 reticular activating system sites, the subcoeruleus nucleus and in the pedunculopontine nucleus, which has been implicated in the modulation of arousal via ascending cholinergic activation of intralaminar thalamus and descending activation of the subcoeruleus nucleus to generate some of the signs of rapid eye movement sleep. We used 6- to 30-day-old rat pups to obtain brainstem slices to perform whole-cell patch-clamp recordings. Recordings from single cells revealed the presence of spikelets, manifestations of action potentials in coupled cells, and of dye coupling of neurons in the pedunculopontine nucleus. Recordings in pairs of pedunculopontine nucleus and subcoeruleus nucleus neurons revealed that some of these were electrically coupled with coupling coefficients of approximately 2%. After blockade of fast synaptic transmission, the cholinergic agonist carbachol was found to induce rhythmic activity in pedunculopontine nucleus and subcoeruleus nucleus neurons, an effect eliminated by the gap junction blockers carbenoxolone or mefloquine. The stimulant modafinil was found to decrease resistance in neurons in the pedunculopontine nucleus and subcoeruleus nucleus after fast synaptic blockade, indicating that the effect may be due to increased coupling. The finding of electrical coupling in specific reticular activating system cell groups supports the concept that this underlying process behind specific neurotransmitter interactions modulates ensemble activity across cell populations to promote changes in sleep-wake state.

  8. Internal pallidum and substantia nigra control different parts of the mesopontine reticular formation in primate.

    PubMed

    Rolland, Anne-Sophie; Karachi, Carine; Muriel, Marie-Paule; Hirsch, Etienne C; François, Chantal

    2011-08-01

    The locomotor area has recently emerged as a target for deep brain stimulation to lessen gait disturbances in advanced parkinsonian patients. An important step in choosing this target is to define anatomical limits of its 2 components, the pedunculopontine nucleus and the cuneiform nucleus, their connections with the basal ganglia, and their output descending pathway. Based on the hypothesis that pedunculopontine nucleus controls locomotion whereas cuneiform nucleus controls axial posture, we analyzed whether both nuclei receive inputs from the internal pallidum and substantia nigra using anterograde and retrograde tract tracing in monkeys. We also examined whether these nuclei convey descending projections to the reticulospinal pathway. Pallidal terminals were densely distributed and restricted to the pedunculopontine nucleus, whereas nigral terminals were diffusely observed in the whole extent of both the pedunculopontine nucleus and the cuneiform nucleus. Moreover, nigral terminals formed symmetric synapses with pedunculopontine nucleus and cuneiform nucleus dendrites. Retrograde tracing experiments confirmed these results because labeled cell bodies were observed in both the internal pallidum and substantia nigra after pedunculopontine nucleus injection, but only in the substantia nigra after cuneiform nucleus injection. Furthermore, anterograde tracing experiments revealed that the pedunculopontine nucleus and cuneiform nucleus project to large portions of the pontomedullary reticular formation. This is the first anatomical evidence that the internal pallidum and the substantia nigra control different parts of the brain stem and can modulate the descending reticulospinal pathway in primates. These findings support the functional hypothesis that the nigro-cuneiform nucleus pathway could control axial posture whereas the pallido-pedunculopontine nucleus pathway could modulate locomotion. Copyright © 2011 Movement Disorder Society.

  9. [Deep brain stimulation in the treatment of movement disorders].

    PubMed

    Goto, Satoshi

    2007-11-01

    The introduction of deep brain stimulation (DBS) was a historical step forward for the treatment of advanced and medically intractable movement disorders that include Parkinson's disease, dystonias, essential tremor, and Holmes' tremor. DBS is able to modulate the target region electrically in a reversible and adjustable fashion in contrast to an irreversible and destructive lesioning procedure. In the treatment of movement disorders, the potential targets are the thalamic ventral intermediate nucleus (Vim), globus pallidus internus (GPi), subthalamic nucleus (STN), pedunculopontine nucleus (PPN), and thalamic Vo-complex nucleus. With the development of DBS technology and stereotactic neurosurgical techniques, its therapeutic efficacy has been increased while reducing surgical complications. DBS has become an established therapy for disabling movement disorders and is currently being used to treat neuropsychiatric disorders.

  10. The network of causal interactions for beta oscillations in the pedunculopontine nucleus, primary motor cortex, and subthalamic nucleus of walking parkinsonian rats.

    PubMed

    Li, Min; Zhou, Ming; Wen, Peng; Wang, Qiang; Yang, Yong; Xiao, Hu; Xie, Zhengyuan; Li, Xing; Wang, Ning; Wang, Jinyan; Luo, Fei; Chang, Jingyu; Zhang, Wangming

    2016-08-01

    Oscillatory activity has been well-studied in many structures within cortico-basal ganglia circuits, but it is not well understood within the pedunculopontine nucleus (PPN), which was recently introduced as a potential target for the treatment of gait and postural impairments in advanced stages of Parkinson's disease (PD). To investigate oscillatory activity in the PPN and its relationship with oscillatory activity in cortico-basal ganglia circuits, we simultaneously recorded local field potentials in the PPN, primary motor cortex (M1), and subthalamic nucleus (STN) of 6-hydroxydopamine (6-OHDA)-induced hemiparkinsonian rats during resting and walking. After analysis of power spectral density, coherence, and partial Granger causality, three major findings emerged: 1) after 6-OHDA lesions, beta band oscillations were enhanced in all three regions during walking; 2) the direction of information flow for beta oscillations among the three structures was STN→M1, STN→PPN, and PPN→M1; 3) after the treatment of levodopa, beta activity in the three regions was reduced significantly and the flow of beta band was also abrogated. Our results suggest that beta activity in the PPN is transmitted from the basal ganglia and probably comes from the STN, and the STN plays a dominant role in the network of causal interactions for beta activity. Thus, the STN may be a potential source of aberrant beta band oscillations in PD. Levodopa can inhibit beta activity in the PPN of parkinsonian rats but cannot relieve parkinsonian patients' axial symptoms clinically. Therefore, beta oscillations may not be the major cause of axial symptoms. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Lesions of cholinergic pedunculopontine tegmental nucleus neurons fail to affect cocaine or heroin self-administration or conditioned place preference in rats.

    PubMed

    Steidl, Stephan; Wang, Huiling; Wise, Roy A

    2014-01-01

    Cholinergic input to the ventral tegmental area (VTA) is known to contribute to reward. Although it is known that the pedunculopontine tegmental nucleus (PPTg) provides an important source of excitatory input to the dopamine system, the specific role of PPTg cholinergic input to the VTA in cocaine reward has not been previously determined. We used a diphtheria toxin conjugated to urotensin-II (Dtx::UII), the endogenous ligand for urotensin-II receptors expressed by PPTg cholinergic but not glutamatergic or GABAergic cells, to lesion cholinergic PPTg neurons. Dtx::UII toxin infusion resulted in the loss of 95.78 (±0.65)% of PPTg cholinergic cells but did not significantly alter either cocaine or heroin self-administration or the development of cocaine or heroin conditioned place preferences. Thus, cholinergic cells originating in PPTg do not appear to be critical for the rewarding effects of cocaine or of heroin.

  12. Electrical Coupling: Novel Mechanism for Sleep-Wake Control

    PubMed Central

    Garcia-Rill, Edgar; Heister, David S.; Ye, Meijun; Charlesworth, Amanda; Hayar, Abdallah

    2007-01-01

    Study Objectives: Recent evidence suggests that certain anesthetic agents decrease electrical coupling, whereas the stimulant modafinil appears to increase electrical coupling. We investigated the potential role of electrical coupling in 2 reticular activating system sites, the subcoeruleus nucleus and in the pedunculopontine nucleus, which has been implicated in the modulation of arousal via ascending cholinergic activation of intralaminar thalamus and descending activation of the subcoeruleus nucleus to generate some of the signs of rapid eye movement sleep. Design: We used 6- to 30-day-old rat pups to obtain brainstem slices to perform whole-cell patch-clamp recordings. Measurements and Results: Recordings from single cells revealed the presence of spikelets, manifestations of action potentials in coupled cells, and of dye coupling of neurons in the pedunculopontine nucleus. Recordings in pairs of pedunculopontine nucleus and subcoeruleus nucleus neurons revealed that some of these were electrically coupled with coupling coefficients of approximately 2%. After blockade of fast synaptic transmission, the cholinergic agonist carbachol was found to induce rhythmic activity in pedunculopontine nucleus and subcoeruleus nucleus neurons, an effect eliminated by the gap junction blockers carbenoxolone or mefloquine. The stimulant modafinil was found to decrease resistance in neurons in the pedunculopontine nucleus and subcoeruleus nucleus after fast synaptic blockade, indicating that the effect may be due to increased coupling. Conclusions: The finding of electrical coupling in specific reticular activating system cell groups supports the concept that this underlying process behind specific neurotransmitter interactions modulates ensemble activity across cell populations to promote changes in sleep-wake state. Citation: Garcia-Rill E; Heister DS; Ye M; Charlesworth A; Hayar A. Electrical coupling: novel mechanism for sleep-wake control. SLEEP 2007;30(11):1405-1414. PMID

  13. The pedunculopontine nucleus is related to visual hallucinations in Parkinson's disease: preliminary results of a voxel-based morphometry study.

    PubMed

    Janzen, J; van 't Ent, D; Lemstra, A W; Berendse, H W; Barkhof, F; Foncke, E M J

    2012-01-01

    Visual hallucinations (VH) are common in Parkinson's disease (PD) and lead to a poor quality of life. For a long time, dopaminergic therapy was considered to be the most important risk factor for the development of VH in PD. Recently, the cholinergic system, including the pedunculopontine nucleus (PPN), has been implicated in the pathophysiology of VH. The aim of the present study was to investigate grey matter density of the PPN region and one of its projection areas, the thalamus. Thirteen non-demented PD patients with VH were compared to 16 non-demented PD patients without VH, 13 demented PD patients (PDD) with VH and 11 patients with dementia with Lewy bodies (DLB). Isotropic 3-D T1-weighted MRI images (3T) were analysed using voxel-based morphometry (VBM) with the PPN region and thalamus as ROIs. PD and PDD patients with VH showed grey matter reductions of the PPN region and the thalamus compared to PD patients without VH. VH in PD(D) patients are associated with atrophy of the PPN region and its thalamic target area, suggesting that a cholinergic deficit may be involved in the development of VH in PD(D).

  14. The anterior and posterior pedunculopontine tegmental nucleus are involved in behavior and neuronal activity of the cuneiform and entopeduncular nuclei.

    PubMed

    Jin, X; Schwabe, K; Krauss, J K; Alam, M

    2016-05-13

    Loss of cholinergic neurons in the mesencephalic locomotor region, comprising the pedunculopontine nucleus (PPN) and the cuneiform nucleus (CnF), is related to gait disturbances in late stage Parkinson's disease (PD). We investigate the effect of anterior or posterior cholinergic lesions of the PPN on gait-related motor behavior, and on neuronal network activity of the PPN area and basal ganglia (BG) motor loop in rats. Anterior PPN lesions, posterior PPN lesions or sham lesions were induced by stereotaxic microinjection of the cholinergic toxin AF64-A or vehicle in male Sprague-Dawley rats. First, locomotor activity (open field), postural disturbances (Rotarod) and gait asymmetry (treadmill test) were assessed. Thereafter, single-unit and oscillatory activities were measured in the non-lesioned area of the PPN, the CnF and the entopeduncular nucleus (EPN), the BG output region, with microelectrodes under urethane anesthesia. Additionally, ECoG was recorded in the motor cortex. Injection of AF64-A into the anterior and posterior PPN decreased cholinergic cell counts as compared to naive controls (P<0.001) but also destroyed non-cholinergic cells. Only anterior PPN lesions decreased the front limb swing time of gait in the treadmill test, while not affecting other gait-related parameters tested. Main electrophysiological findings were that anterior PPN lesions increased the firing activity in the CnF (P<0.001). Further, lesions of either PPN region decreased the coherence of alpha (8-12 Hz) band between CnF and motor cortex (MCx), and increased the beta (12-30 Hz) oscillatory synchronization between EPN and the MCx. Lesions of the PPN in rats had complex effects on oscillatory neuronal activity of the CnF and the BG network, which may contribute to the understanding of the pathophysiology of gait disturbance in PD. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

  15. Motor and Nonmotor Circuitry Activation Induced by Subthalamic Nucleus Deep Brain Stimulation in Patients With Parkinson Disease: Intraoperative Functional Magnetic Resonance Imaging for Deep Brain Stimulation.

    PubMed

    Knight, Emily J; Testini, Paola; Min, Hoon-Ki; Gibson, William S; Gorny, Krzysztof R; Favazza, Christopher P; Felmlee, Joel P; Kim, Inyong; Welker, Kirk M; Clayton, Daniel A; Klassen, Bryan T; Chang, Su-youne; Lee, Kendall H

    2015-06-01

    To test the hypothesis suggested by previous studies that subthalamic nucleus (STN) deep brain stimulation (DBS) in patients with Parkinson disease would affect the activity of motor and nonmotor networks, we applied intraoperative functional magnetic resonance imaging (fMRI) to patients receiving DBS. Ten patients receiving STN DBS for Parkinson disease underwent intraoperative 1.5-T fMRI during high-frequency stimulation delivered via an external pulse generator. The study was conducted between January 1, 2013, and September 30, 2014. We observed blood oxygen level-dependent (BOLD) signal changes (false discovery rate <0.001) in the motor circuitry (including the primary motor, premotor, and supplementary motor cortices; thalamus; pedunculopontine nucleus; and cerebellum) and in the limbic circuitry (including the cingulate and insular cortices). Activation of the motor network was observed also after applying a Bonferroni correction (P<.001) to the data set, suggesting that across patients, BOLD changes in the motor circuitry are more consistent compared with those occurring in the nonmotor network. These findings support the modulatory role of STN DBS on the activity of motor and nonmotor networks and suggest complex mechanisms as the basis of the efficacy of this treatment modality. Furthermore, these results suggest that across patients, BOLD changes in the motor circuitry are more consistent than those in the nonmotor network. With further studies combining the use of real-time intraoperative fMRI with clinical outcomes in patients treated with DBS, functional imaging techniques have the potential not only to elucidate the mechanisms of DBS functioning but also to guide and assist in the surgical treatment of patients affected by movement and neuropsychiatric disorders. clinicaltrials.gov Identifier: NCT01809613. Copyright © 2015 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

  16. Brain networks modulated by subthalamic nucleus deep brain stimulation.

    PubMed

    Accolla, Ettore A; Herrojo Ruiz, Maria; Horn, Andreas; Schneider, Gerd-Helge; Schmitz-Hübsch, Tanja; Draganski, Bogdan; Kühn, Andrea A

    2016-09-01

    Deep brain stimulation of the subthalamic nucleus is an established treatment for the motor symptoms of Parkinson's disease. Given the frequent occurrence of stimulation-induced affective and cognitive adverse effects, a better understanding about the role of the subthalamic nucleus in non-motor functions is needed. The main goal of this study is to characterize anatomical circuits modulated by subthalamic deep brain stimulation, and infer about the inner organization of the nucleus in terms of motor and non-motor areas. Given its small size and anatomical intersubject variability, functional organization of the subthalamic nucleus is difficult to investigate in vivo with current methods. Here, we used local field potential recordings obtained from 10 patients with Parkinson's disease to identify a subthalamic area with an analogous electrophysiological signature, namely a predominant beta oscillatory activity. The spatial accuracy was improved by identifying a single contact per macroelectrode for its vicinity to the electrophysiological source of the beta oscillation. We then conducted whole brain probabilistic tractography seeding from the previously identified contacts, and further described connectivity modifications along the macroelectrode's main axis. The designated subthalamic 'beta' area projected predominantly to motor and premotor cortical regions additional to connections to limbic and associative areas. More ventral subthalamic areas showed predominant connectivity to medial temporal regions including amygdala and hippocampus. We interpret our findings as evidence for the convergence of different functional circuits within subthalamic nucleus' portions deemed to be appropriate as deep brain stimulation target to treat motor symptoms in Parkinson's disease. Potential clinical implications of our study are illustrated by an index case where deep brain stimulation of estimated predominant non-motor subthalamic nucleus induced hypomanic behaviour. © The

  17. Neuropharmacological mechanisms of drug reward: beyond dopamine in the nucleus accumbens.

    PubMed

    Bardo, M T

    1998-01-01

    Multiple lines of research have implicated the mesolimbic dopamine system in drug reward measured by either the drug self-administration or conditioned place preference paradigm. The present review summarizes recent work that examines the neuropharmacological mechanisms by which drugs impinge on this dopaminergic neural circuitry, as well as other systems that provide input and output circuits to the mesolimbic dopamine system. Studies examining the effect of selective agonist and antagonist drugs administered systemically have indicated that multiple neurotransmitters are involved, including dopamine, serotonin, acetylcholine, glutamate, GABA, and various peptides. Direct microinjection studies have also provided crucial evidence indicating that, in addition to the mesolimbic dopamine system, other structures play a role in drug reward, including the ventral pallidum, amygdala, hippocampus, hypothalamus, and pedunculopontine tegmental nucleus. GABAergic circuitry descending from the nucleus accumbens to the pedunculopontine tegmental nucleus via the ventral pallidum appears to be especially important in directing the behavioral sequelae associated with reward produced by various drugs of abuse. However, activation of the reward circuitry is achieved differently for various drugs of abuse. With amphetamine and cocaine, initiation of reward is controlled within the nucleus accumbens and prefrontal cortex, respectively. With opiates, initiation of reward involves the ventral tegmental area, nucleus accumbens, hippocampus, and hypothalamus. It is not clear presently if these multiple anatomical structures mediate opiate reward by converging on a single output system or multiple output systems.

  18. Tractography patterns of subthalamic nucleus deep brain stimulation.

    PubMed

    Vanegas-Arroyave, Nora; Lauro, Peter M; Huang, Ling; Hallett, Mark; Horovitz, Silvina G; Zaghloul, Kareem A; Lungu, Codrin

    2016-04-01

    Deep brain stimulation therapy is an effective symptomatic treatment for Parkinson's disease, yet the precise mechanisms responsible for its therapeutic effects remain unclear. Although the targets of deep brain stimulation are grey matter structures, axonal modulation is known to play an important role in deep brain stimulation's therapeutic mechanism. Several white matter structures in proximity to the subthalamic nucleus have been implicated in the clinical benefits of deep brain stimulation for Parkinson's disease. We assessed the connectivity patterns that characterize clinically beneficial electrodes in Parkinson's disease patients, after deep brain stimulation of the subthalamic nucleus. We evaluated 22 patients with Parkinson's disease (11 females, age 57 ± 9.1 years, disease duration 13.3 ± 6.3 years) who received bilateral deep brain stimulation of the subthalamic nucleus at the National Institutes of Health. During an initial electrode screening session, one month after deep brain stimulation implantation, the clinical benefits of each contact were determined. The electrode was localized by coregistering preoperative magnetic resonance imaging and postoperative computer tomography images and the volume of tissue activated was estimated from stimulation voltage and impedance. Brain connectivity for the volume of tissue activated of deep brain stimulation contacts was assessed using probabilistic tractography with diffusion-tensor data. Areas most frequently connected to clinically effective contacts included the thalamus, substantia nigra, brainstem and superior frontal gyrus. A series of discriminant analyses demonstrated that the strength of connectivity to the superior frontal gyrus and the thalamus were positively associated with clinical effectiveness. The connectivity patterns observed in our study suggest that the modulation of white matter tracts directed to the superior frontal gyrus and the thalamus is associated with favourable clinical

  19. [The effects of lesions in the compact part of the substantia nigra on glutamate and GABA release in the pedunculopontine nucleus].

    PubMed

    Blanco-Lezcano, L; Rocha-Arrieta, L L; Alvarez-González, L; Martínez-Martí, L; Pavón-Fuentes, N; González-Fraguela, M E; Bauzá-Calderín, Y; Coro-Grave de Peralta, Y

    The pedunculopontine nucleus (PPN), co-localized with the mesencephalic locomotor region, has been proposed as a key structure in the physiopathology of Parkinson's disease. The goal of the present study was to assess if the aminoacid neurotransmitter release in the PPN is modified by the degeneration of dopaminergic cells, from substantia nigra pars compacta in 6-hydroxidopamine (6-OHDA)-lesioned rats. In addition, it was studied the aminoacid neurotransmitter release in the PPN of rats with lesion of the subthalamic nucleus by quinolinic acid (QUIN) (100 nmol) intracerebral injection. Rats were assigned to five groups: untreated rats (I) (n = 13), 6-OHDA lesion (II) (n = 11), 6-OHDA + QUIN lesion (III) (n = 9), sham-operated (IV) (n = 10), QUIN, STN (V) lesioned (n = 9). The extracellular concentrations of glutamic acid (GLU) and gamma-aminobutyric acid (GABA) were determined by brain microdialysis and high performance liquid chromatography (HPLC). RESULTS. GLU released in PPN from 6-OHDA lesioned rats (group II), was significantly increased in comparison with the others groups (F(4, 47) = 18.21, p < 0.001). GABA released shows significant differences between experimental groups (F(4, 45) = 12.75, p < 0.001). It was detected a higher valour (p < 0.05) in-group II. The groups III and IV exhibited intermeddle valour (p < 0.001) and groups I and IV (p < 0.001) showed the lower GABA extracellular concentrations. The infusion of artificial cerebrospinal fluid with higher potassium (100 mmol) induced an increase in the GLU and GABA released in all groups, which confirm the neuronal origin of the extracellular content. These results are in agreement with the current model of basal ganglia functioning and suggest the role of STN-PPN projection in the physiopathology of Parkinson's disease.

  20. Paradoxical augmented relapse in alcohol-dependent rats during deep-brain stimulation in the nucleus accumbens

    PubMed Central

    Hadar, R; Vengeliene, V; Barroeta Hlusicke, E; Canals, S; Noori, H R; Wieske, F; Rummel, J; Harnack, D; Heinz, A; Spanagel, R; Winter, C

    2016-01-01

    Case reports indicate that deep-brain stimulation in the nucleus accumbens may be beneficial to alcohol-dependent patients. The lack of clinical trials and our limited knowledge of deep-brain stimulation call for translational experiments to validate these reports. To mimic the human situation, we used a chronic-continuous brain-stimulation paradigm targeting the nucleus accumbens and other brain sites in alcohol-dependent rats. To determine the network effects of deep-brain stimulation in alcohol-dependent rats, we combined electrical stimulation of the nucleus accumbens with functional magnetic resonance imaging (fMRI), and studied neurotransmitter levels in nucleus accumbens-stimulated versus sham-stimulated rats. Surprisingly, we report here that electrical stimulation of the nucleus accumbens led to augmented relapse behavior in alcohol-dependent rats. Our associated fMRI data revealed some activated areas, including the medial prefrontal cortex and caudate putamen. However, when we applied stimulation to these areas, relapse behavior was not affected, confirming that the nucleus accumbens is critical for generating this paradoxical effect. Neurochemical analysis of the major activated brain sites of the network revealed that the effect of stimulation may depend on accumbal dopamine levels. This was supported by the finding that brain-stimulation-treated rats exhibited augmented alcohol-induced dopamine release compared with sham-stimulated animals. Our data suggest that deep-brain stimulation in the nucleus accumbens enhances alcohol-liking probably via augmented dopamine release and can thereby promote relapse. PMID:27327255

  1. On the Role of the Pedunculopontine Nucleus and Mesencephalic Reticular Formation in Locomotion in Nonhuman Primates.

    PubMed

    Goetz, Laurent; Piallat, Brigitte; Bhattacharjee, Manik; Mathieu, Hervé; David, Olivier; Chabardès, Stéphan

    2016-05-04

    The mesencephalic reticular formation (MRF) is formed by the pedunculopontine and cuneiform nuclei, two neuronal structures thought to be key elements in the supraspinal control of locomotion, muscle tone, waking, and REM sleep. The role of MRF has also been advocated in modulation of state of arousal leading to transition from wakefulness to sleep and it is further considered to be a main player in the pathophysiology of gait disorders seen in Parkinson's disease. However, the existence of a mesencephalic locomotor region and of an arousal center has not yet been demonstrated in primates. Here, we provide the first extensive electrophysiological mapping of the MRF using extracellular recordings at rest and during locomotion in a nonhuman primate (NHP) (Macaca fascicularis) model of bipedal locomotion. We found different neuronal populations that discharged according to a phasic or a tonic mode in response to locomotion, supporting the existence of a locomotor neuronal circuit within these MRF in behaving primates. Altogether, these data constitute the first electrophysiological characterization of a locomotor neuronal system present within the MRF in behaving NHPs under normal conditions, in accordance with several studies done in different experimental animal models. We provide the first extensive electrophysiological mapping of the two major components of the mesencephalic reticular formation (MRF), namely the pedunculopontine and cuneiform nuclei. We exploited a nonhuman primate (NHP) model of bipedal locomotion with extracellular recordings in behaving NHPs at rest and during locomotion. Different MRF neuronal groups were found to respond to locomotion, with phasic or tonic patterns of response. These data constitute the first electrophysiological evidences of a locomotor neuronal system within the MRF in behaving NHPs. Copyright © 2016 the authors 0270-6474/16/364917-13$15.00/0.

  2. Motor and non-motor circuitry activation induced by subthalamic nucleus deep brain stimulation (STN DBS) in Parkinson’s disease patients: Intraoperative fMRI for DBS

    PubMed Central

    Knight, Emily J.; Testini, Paola; Min, Hoon-Ki; Gibson, William S.; Gorny, Krzysztof R.; Favazza, Christopher P.; Felmlee, Joel P.; Kim, Inyong; Welker, Kirk M.; Clayton, Daniel A.; Klassen, Bryan T.; Chang, Su-youne; Lee, Kendall H.

    2015-01-01

    Objective To test the hypothesis suggested by previous studies that subthalamic nucleus (STN) deep brain stimulation (DBS) in patients with PD would affect the activity of both motor and non-motor networks, we applied intraoperative fMRI to patients receiving DBS. Patients and Methods Ten patients receiving STN DBS for PD underwent intraoperative 1.5T fMRI during high frequency stimulation delivered via an external pulse generator. The study was conducted between the dates of January 1, 2013 and September 30, 2014. Results We observed blood oxygen level dependent (BOLD) signal changes (FDR<.001) in the motor circuitry, including primary motor, premotor, and supplementary motor cortices, thalamus, pedunculopontine nucleus (PPN), and cerebellum, as well as in the limbic circuitry, including cingulate and insular cortices. Activation of the motor network was observed also after applying a Bonferroni correction (p<.001) to our dataset, suggesting that, across subjects, BOLD changes in the motor circuitry are more consistent compared to those occurring in the non-motor network. Conclusions These findings support the modulatory role of STN DBS on the activity of motor and non-motor networks, and suggest complex mechanisms at the basis of the efficacy of this treatment modality. Furthermore, these results suggest that, across subjects, BOLD changes in the motor circuitry are more consistent compared to those occurring in the non-motor network. With further studies combining the use of real time intraoperative fMRI with clinical outcomes in patients treated with DBS, functional imaging techniques have the potential not only to elucidate the mechanisms of DBS functioning, but also to guide and assist in the surgical treatment of patients affected by movement and neuropsychiatric disorders. PMID:26046412

  3. Auditory Responses to Electric and Infrared Neural Stimulation of the Rat Cochlear Nucleus

    PubMed Central

    Verma, Rohit; Guex, Amelie A.; Hancock, Kenneth E.; Durakovic, Nedim; McKay, Colette M.; Slama, Michaël C. C.; Brown, M. Christian; Lee, Daniel J.

    2014-01-01

    In an effort to improve the auditory brainstem implant, a prosthesis in which user outcomes are modest, we applied electric and infrared neural stimulation (INS) to the cochlear nucleus in a rat animal model. Electric stimulation evoked regions of neural activation in the inferior colliculus and short-latency, multipeaked auditory brainstem responses (ABRs). Pulsed INS, delivered to the surface of the cochlear nucleus via an optical fiber, evoked broad neural activation in the inferior colliculus. Strongest responses were recorded when the fiber was placed at lateral positions on the cochlear nucleus, close to the temporal bone. INS-evoked ABRs were multipeaked but longer in latency than those for electric stimulation; they resembled the responses to acoustic stimulation. After deafening, responses to electric stimulation persisted, whereas those to INS disappeared, consistent with a reported “optophonic” effect, a laser-induced acoustic artifact. Thus, for deaf individuals who use the auditory brainstem implant, INS alone did not appear promising as a new approach. PMID:24508368

  4. Subthalamic nucleus stimulation-induced regional blood flow responses correlate with improvement of motor signs in Parkinson disease.

    PubMed

    Karimi, M; Golchin, N; Tabbal, S D; Hershey, T; Videen, T O; Wu, J; Usche, J W M; Revilla, F J; Hartlein, J M; Wernle, A R; Mink, J W; Perlmutter, J S

    2008-10-01

    Deep brain stimulation of the subthalamic nucleus (STN DBS) improves motor symptoms in idiopathic Parkinson's disease, yet the mechanism of action remains unclear. Previous studies indicate that STN DBS increases regional cerebral blood flow (rCBF) in immediate downstream targets but does not reveal which brain regions may have functional changes associated with improved motor manifestations. We studied 48 patients with STN DBS who withheld medication overnight and underwent PET scans to measure rCBF responses to bilateral STN DBS. PET scans were performed with bilateral DBS OFF and ON in a counterbalanced order followed by clinical ratings of motor manifestations using Unified Parkinson Disease Rating Scale 3 (UPDRS 3). We investigated whether improvement in UPDRS 3 scores in rigidity, bradykinesia, postural stability and gait correlate with rCBF responses in a priori determined regions. These regions were selected based on a previous study showing significant STN DBS-induced rCBF change in the thalamus, midbrain and supplementary motor area (SMA). We also chose the pedunculopontine nucleus region (PPN) due to mounting evidence of its involvement in locomotion. In the current study, bilateral STN DBS improved rigidity (62%), bradykinesia (44%), gait (49%) and postural stability (56%) (paired t-tests: P < 0.001). As expected, bilateral STN DBS also increased rCBF in the bilateral thalami, right midbrain, and decreased rCBF in the right premotor cortex (P < 0.05, corrected). There were significant correlations between improvement of rigidity and decreased rCBF in the SMA (r(s) = -0.4, P < 0.02) and between improvement in bradykinesia and increased rCBF in the thalamus (r(s) = 0.31, P < 0.05). In addition, improved postural reflexes correlated with decreased rCBF in the PPN (r(s) = -0.38, P < 0.03). These modest correlations between selective motor manifestations and rCBF in specific regions suggest possible regional selectivity for improvement of different motor

  5. Subthalamic nucleus stimulation-induced regional blood flow responses correlate with improvement of motor signs in Parkinson disease

    PubMed Central

    Karimi, M.; Golchin, N.; Tabbal, S. D.; Hershey, T.; Videen, T. O.; Wu, J.; Usche, J. W. M.; Revilla, F. J.; Hartlein, J. M.; Wernle, A. R.; Mink, J. W.

    2008-01-01

    Deep brain stimulation of the subthalamic nucleus (STN DBS) improves motor symptoms in idiopathic Parkinson's disease, yet the mechanism of action remains unclear. Previous studies indicate that STN DBS increases regional cerebral blood flow (rCBF) in immediate downstream targets but does not reveal which brain regions may have functional changes associated with improved motor manifestations. We studied 48 patients with STN DBS who withheld medication overnight and underwent PET scans to measure rCBF responses to bilateral STN DBS. PET scans were performed with bilateral DBS OFF and ON in a counterbalanced order followed by clinical ratings of motor manifestations using Unified Parkinson Disease Rating Scale 3 (UPDRS 3). We investigated whether improvement in UPDRS 3 scores in rigidity, bradykinesia, postural stability and gait correlate with rCBF responses in a priori determined regions. These regions were selected based on a previous study showing significant STN DBS-induced rCBF change in the thalamus, midbrain and supplementary motor area (SMA). We also chose the pedunculopontine nucleus region (PPN) due to mounting evidence of its involvement in locomotion. In the current study, bilateral STN DBS improved rigidity (62%), bradykinesia (44%), gait (49%) and postural stability (56%) (paired t-tests: P < 0.001). As expected, bilateral STN DBS also increased rCBF in the bilateral thalami, right midbrain, and decreased rCBF in the right premotor cortex (P < 0.05, corrected). There were significant correlations between improvement of rigidity and decreased rCBF in the SMA (rs = –0.4, P < 0.02) and between improvement in bradykinesia and increased rCBF in the thalamus (rs = 0.31, P < 0.05). In addition, improved postural reflexes correlated with decreased rCBF in the PPN (rs = –0.38, P < 0.03). These modest correlations between selective motor manifestations and rCBF in specific regions suggest possible regional selectivity for improvement of different motor signs

  6. Subthalamic nucleus stimulation influences expression and suppression of impulsive behaviour in Parkinson’s disease

    PubMed Central

    Ridderinkhof, K. Richard; Elias, William J.; Frysinger, Robert C.; Bashore, Theodore R.; Downs, Kara E.; van Wouwe, Nelleke C.; van den Wildenberg, Wery P. M.

    2010-01-01

    Past studies show beneficial as well as detrimental effects of subthalamic nucleus deep-brain stimulation on impulsive behaviour. We address this paradox by investigating individuals with Parkinson’s disease treated with subthalamic nucleus stimulation (n = 17) and healthy controls without Parkinson’s disease (n = 17) on performance in a Simon task. In this reaction time task, conflict between premature response impulses and goal-directed action selection is manipulated. We applied distributional analytic methods to separate the strength of the initial response impulse from the proficiency of inhibitory control engaged subsequently to suppress the impulse. Patients with Parkinson’s disease were tested when stimulation was either turned on or off. Mean conflict interference effects did not differ between controls and patients, or within patients when stimulation was on versus off. In contrast, distributional analyses revealed two dissociable effects of subthalamic nucleus stimulation. Fast response errors indicated that stimulation increased impulsive, premature responding in high conflict situations. Later in the reaction process, however, stimulation improved the proficiency with which inhibitory control was engaged to suppress these impulses selectively, thereby facilitating selection of the correct action. This temporal dissociation supports a conceptual framework for resolving past paradoxical findings and further highlights that dynamic aspects of impulse and inhibitory control underlying goal-directed behaviour rely in part on neural circuitry inclusive of the subthalamic nucleus. PMID:20861152

  7. Auditory responses to electric and infrared neural stimulation of the rat cochlear nucleus.

    PubMed

    Verma, Rohit U; Guex, Amélie A; Hancock, Kenneth E; Durakovic, Nedim; McKay, Colette M; Slama, Michaël C C; Brown, M Christian; Lee, Daniel J

    2014-04-01

    In an effort to improve the auditory brainstem implant, a prosthesis in which user outcomes are modest, we applied electric and infrared neural stimulation (INS) to the cochlear nucleus in a rat animal model. Electric stimulation evoked regions of neural activation in the inferior colliculus and short-latency, multipeaked auditory brainstem responses (ABRs). Pulsed INS, delivered to the surface of the cochlear nucleus via an optical fiber, evoked broad neural activation in the inferior colliculus. Strongest responses were recorded when the fiber was placed at lateral positions on the cochlear nucleus, close to the temporal bone. INS-evoked ABRs were multipeaked but longer in latency than those for electric stimulation; they resembled the responses to acoustic stimulation. After deafening, responses to electric stimulation persisted, whereas those to INS disappeared, consistent with a reported "optophonic" effect, a laser-induced acoustic artifact. Thus, for deaf individuals who use the auditory brainstem implant, INS alone did not appear promising as a new approach. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Decisional impulsivity and the associative-limbic subthalamic nucleus in obsessive-compulsive disorder: stimulation and connectivity

    PubMed Central

    Voon, Valerie; Droux, Fabien; Morris, Laurel; Chabardes, Stephan; Bougerol, Thierry; David, Olivier; Krack, Paul; Polosan, Mircea

    2017-01-01

    Abstract Why do we make hasty decisions for short-term gain? Rapid decision-making with limited accumulation of evidence and delay discounting are forms of decisional impulsivity. The subthalamic nucleus is implicated in inhibitory function but its role in decisional impulsivity is less well-understood. Here we assess decisional impulsivity in subjects with obsessive compulsive disorder who have undergone deep brain stimulation of the limbic and associative subthalamic nucleus. We show that stimulation of the subthalamic nucleus is causally implicated in increasing decisional impulsivity with less accumulation of evidence during probabilistic uncertainty and in enhancing delay discounting. Subthalamic stimulation shifts evidence accumulation in subjects with obsessive-compulsive disorder towards a functional less cautious style closer to that of healthy controls emphasizing its adaptive nature. Thus, subjects with obsessive compulsive disorder on subthalamic stimulation may be less likely to check for evidence (e.g. checking that the stove is on) with no difference in subjective confidence (or doubt). In a separate study, we replicate in humans (154 healthy controls) using resting state functional connectivity, tracing studies conducted in non-human primates dissociating limbic, associative and motor frontal hyper-direct connectivity with anterior and posterior subregions of the subthalamic nucleus. We show lateralization of functional connectivity of bilateral ventral striatum to right anterior ventromedial subthalamic nucleus consistent with previous observations of lateralization of emotionally evoked activity to right ventral subthalamic nucleus. We use a multi-echo sequence with independent components analysis, which has been shown to have enhanced signal-to-noise ratio, thus optimizing visualization of small subcortical structures. These findings in healthy controls converge with the effective contacts in obsessive compulsive disorder patients localized

  9. Subthalamic Nucleus Stimulation and Dysarthria in Parkinson's Disease: A PET Study

    ERIC Educational Resources Information Center

    Pinto, Serge; Thobois, Stephane; Costes, Nicolas; Le Bars, Didier; Benabid, Alim-Louis; Broussolle, Emmanuel; Pollak, Pierre; Gentil, Michele

    2004-01-01

    In Parkinson's disease, functional imaging studies during limb motor tasks reveal cerebral activation abnormalities that can be reversed by subthalamic nucleus (STN) stimulation. The effect of STN stimulation on parkinsonian dysarthria has not, however, been investigated using PET. The aim of the present study was to evaluate the effect of STN…

  10. Decisional impulsivity and the associative-limbic subthalamic nucleus in obsessive-compulsive disorder: stimulation and connectivity.

    PubMed

    Voon, Valerie; Droux, Fabien; Morris, Laurel; Chabardes, Stephan; Bougerol, Thierry; David, Olivier; Krack, Paul; Polosan, Mircea

    2017-02-01

    Why do we make hasty decisions for short-term gain? Rapid decision-making with limited accumulation of evidence and delay discounting are forms of decisional impulsivity. The subthalamic nucleus is implicated in inhibitory function but its role in decisional impulsivity is less well-understood. Here we assess decisional impulsivity in subjects with obsessive compulsive disorder who have undergone deep brain stimulation of the limbic and associative subthalamic nucleus. We show that stimulation of the subthalamic nucleus is causally implicated in increasing decisional impulsivity with less accumulation of evidence during probabilistic uncertainty and in enhancing delay discounting. Subthalamic stimulation shifts evidence accumulation in subjects with obsessive-compulsive disorder towards a functional less cautious style closer to that of healthy controls emphasizing its adaptive nature. Thus, subjects with obsessive compulsive disorder on subthalamic stimulation may be less likely to check for evidence (e.g. checking that the stove is on) with no difference in subjective confidence (or doubt). In a separate study, we replicate in humans (154 healthy controls) using resting state functional connectivity, tracing studies conducted in non-human primates dissociating limbic, associative and motor frontal hyper-direct connectivity with anterior and posterior subregions of the subthalamic nucleus. We show lateralization of functional connectivity of bilateral ventral striatum to right anterior ventromedial subthalamic nucleus consistent with previous observations of lateralization of emotionally evoked activity to right ventral subthalamic nucleus. We use a multi-echo sequence with independent components analysis, which has been shown to have enhanced signal-to-noise ratio, thus optimizing visualization of small subcortical structures. These findings in healthy controls converge with the effective contacts in obsessive compulsive disorder patients localized within the

  11. Deep brain stimulation of the subthalamic nucleus enhances emotional processing in Parkinson disease.

    PubMed

    Schneider, Frank; Habel, Ute; Volkmann, Jens; Regel, Sabine; Kornischka, Jürgen; Sturm, Volker; Freund, Hans-Joachim

    2003-03-01

    High-frequency electrical stimulation of the subthalamic nucleus is a new and highly effective therapy for complications of long-term levodopa therapy and motor symptoms in advanced Parkinson disease (PD). Clinical observations indicate additional influence on emotional behavior. Electrical stimulation of deep brain nuclei with pulse rates above 100 Hz provokes a reversible, lesioning-like effect. Here, the effect of deep brain stimulation of the subthalamic nucleus on emotional, cognitive, and motor performance in patients with PD (n = 12) was examined. The results were compared with the effects of a suprathreshold dose of levodopa intended to transiently restore striatal dopamine deficiency. Patients were tested during medication off/stimulation off (STIM OFF), medication off/stimulation on (STIM ON), and during the best motor state after taking levodopa without deep brain stimulation (MED). More positive self-reported mood and an enhanced mood induction effect as well as improvement in emotional memory during STIM ON were observed, while during STIM OFF, patients revealed reduced emotional performance. Comparable effects were revealed by STIM ON and MED. Cognitive performance was not affected by the different conditions and treatments. Deep brain stimulation of the subthalamic nucleus selectively enhanced affective processing and subjective well-being and seemed to be antidepressive. Levodopa and deep brain stimulation had similar effects on emotion. This finding may provide new clues about the neurobiologic bases of emotion and mood disorders, and it illustrates the important role of the basal ganglia and the dopaminergic system in emotional processing in addition to the well-known motor and cognitive functions.

  12. Response properties of nucleus reticularis lateralis neurons after electroacupuncture stimulation in rats.

    PubMed

    Moritaka, Kentaro; Zeredo, Jorge L; Kimoto, Mari; Nasution, Fajar H; Hirano, Takafumi; Toda, Kazuo

    2010-01-01

    A descending inhibitory mechanism from the periaqueductal gray (PAG) to the spinal cord through the nucleus raphe magnus (NRM) is strongly involved in endogenous analgesic system produced by acupuncture stimulation. In addition to the PAG to NRM system which descends in the medial pathway of the brain stem, the nucleus reticularis lateralis (NRL) situated in the lateral part of the brain stem is reported to play an important role in modulating centrifugal antinociceptive action. In the present study, to clarify the role of NRL in acupuncture analgesia, we investigated the response properties of NRL neurons to acupuncture stimulation. The majority of NRM-projecting NRL neurons were inhibited by electroacupuncture stimulation. This effect was antagonized by ionophoretic application of naloxone, indicating that endogenous opioids act directly onto these NRL neurons. By contrast, about half of spinal projecting NRL neurons were excited by electroacupuncture stimulation, suggesting that part of the NRL neurons may modulate pain transmission directly at the spinal level.

  13. Normalizing motor-related brain activity: subthalamic nucleus stimulation in Parkinson disease.

    PubMed

    Grafton, S T; Turner, R S; Desmurget, M; Bakay, R; Delong, M; Vitek, J; Crutcher, M

    2006-04-25

    To test whether therapeutic unilateral deep brain stimulation (DBS) of the subthalamic nucleus (STN) in patients with Parkinson disease (PD) leads to normalization in the pattern of brain activation during movement execution and control of movement extent. Six patients with PD were imaged off medication by PET during performance of a visually guided tracking task with the DBS voltage programmed for therapeutic (effective) or subtherapeutic (ineffective) stimulation. Data from patients with PD during ineffective stimulation were compared with a group of 13 age-matched control subjects to identify sites with abnormal patterns of activation. Conjunction analysis was used to identify those areas in patients with PD where activity normalized when they were treated with effective stimulation. For movement execution, effective DBS caused an increase of activation in the supplementary motor area (SMA), superior parietal cortex, and cerebellum toward a more normal pattern. At rest, effective stimulation reduced overactivity of SMA. Therapeutic stimulation also induced reductions of movement related "overactivity" compared with healthy subjects in prefrontal, temporal lobe, and basal ganglia circuits, consistent with the notion that many areas are recruited to compensate for ineffective motor initiation. Normalization of activity related to the control of movement extent was associated with reductions of activity in primary motor cortex, SMA, and basal ganglia. Effective subthalamic nucleus stimulation leads to task-specific modifications with appropriate recruitment of motor areas as well as widespread, nonspecific reductions of compensatory or competing cortical activity.

  14. [Emotion and basal ganglia (II): what can we learn from subthalamic nucleus deep brain stimulation in Parkinson's disease?].

    PubMed

    Péron, J; Dondaine, T

    2012-01-01

    The subthalamic nucleus deep-brain stimulation Parkinson's disease patient model seems to represent a unique opportunity for studying the functional role of the basal ganglia and notably the subthalamic nucleus in human emotional processing. Indeed, in addition to constituting a therapeutic advance for severely disabled Parkinson's disease patients, deep brain stimulation is a technique, which selectively modulates the activity of focal structures targeted by surgery. There is growing evidence of a link between emotional impairments and deep-brain stimulation of the subthalamic nucleus. In this context, according to the definition of emotional processing exposed in the companion paper available in this issue, the aim of the present review will consist in providing a synopsis of the studies that investigated the emotional disturbances observed in subthalamic nucleus deep brain stimulation Parkinson's disease patients. This review leads to the conclusion that several emotional components would be disrupted after subthalamic nucleus deep brain stimulation in Parkinson's disease: subjective feeling, neurophysiological activation, and motor expression. Finally, after a description of the limitations of this study model, we discuss the functional role of the subthalamic nucleus (and the striato-thalamo-cortical circuits in which it is involved) in emotional processing. It seems reasonable to conclude that the striato-thalamo-cortical circuits are indeed involved in emotional processing and that the subthalamic nucleus plays a central in role the human emotional architecture. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  15. Effect of l-DOPA on local field potential relationship between the pedunculopontine nucleus and primary motor cortex in a rat model of Parkinson's disease.

    PubMed

    Geng, Xiwen; Wang, Xuenan; Xie, Jinlu; Zhang, Xiao; Wang, Xiusong; Hou, Yabing; Lei, Chengdong; Li, Min; Han, Hongyu; Yao, Xiaomeng; Zhang, Qun; Wang, Min

    2016-12-15

    Levodopa (l-DOPA) has been proved to reverse the pathologic neuron activities in many brain regions related to Parkinson's disease (PD). But little is known about the effect of l-DOPA on the altered electrophysiological coherent activities between pedunculopontine nucleus (PPN) and motor cortex. To investigate this, local field potentials (LFPs) of PPN and primary motor cortex (M1) were recorded simultaneously in control, 6-hydroxydopamine lesioned and lesioned rats with l-DOPA chronic treatment. The results revealed that in resting state, chronic l-DOPA treatment could correct the suppressed power of LFPs in PPN and M1 in low-frequency band (1-7Hz) and the enhanced power in high-frequency band (7-70Hz in PPN and 12-70Hz in M1) of lesioned rats. In locomotor state, l-DOPA treatment could correct the alterations in most of frequency bands except the δ band in PPN and α band in M1. Moreover, l-DOPA could also reverse the altered coherent relationships caused by dopamine depletion in resting state between PPN and M1 in β band. And in locomotor state, l-DOPA had therapeutic effect on the alterations in δ and β bands but not in the α band. These findings provide evidence that l-DOPA can reverse the altered LFP activities in PPN and M1 and their relationships in a rat model of PD, which contributes to better understanding the electrophysiological mechanisms of the pathophysiology and therapy of PD. Copyright © 2016. Published by Elsevier B.V.

  16. Hearing assessment during deep brain stimulation of the central nucleus of the inferior colliculus and dentate cerebellar nucleus in rat.

    PubMed

    Smit, Jasper V; Jahanshahi, Ali; Janssen, Marcus L F; Stokroos, Robert J; Temel, Yasin

    2017-01-01

    Recently it has been shown in animal studies that deep brain stimulation (DBS) of auditory structures was able to reduce tinnitus-like behavior. However, the question arises whether hearing might be impaired when interfering in auditory-related network loops with DBS. The auditory brainstem response (ABR) was measured in rats during high frequency stimulation (HFS) and low frequency stimulation (LFS) in the central nucleus of the inferior colliculus (CIC, n  = 5) or dentate cerebellar nucleus (DCBN, n  = 5). Besides hearing thresholds using ABR, relative measures of latency and amplitude can be extracted from the ABR. In this study ABR thresholds, interpeak latencies (I-III, III-V, I-V) and V/I amplitude ratio were measured during off-stimulation state and during LFS and HFS. In both the CIC and the CNBN groups, no significant differences were observed for all outcome measures. DBS in both the CIC and the CNBN did not have adverse effects on hearing measurements. These findings suggest that DBS does not hamper physiological processing in the auditory circuitry.

  17. Stridor and dysphagia associated with subthalamic nucleus stimulation in Parkinson disease.

    PubMed

    Fagbami, Oluwakemi Y; Donato, Anthony A

    2011-11-01

    Refractory symptoms in Parkinson disease show good response to deep brain stimulation (DBS). This procedure improves United Parkinson's Disease Rating Scale scores and reduces dyskinesias, whereas speech and swallowing dysfunction typically do not improve and may even worsen. Rarely, DBS can cause idiosyncratic dystonias of muscle groups, including those of the neck and throat. The authors describe a patient experiencing stridor and dysphagia with confirmed pulmonary restriction and aspiration following subthalamic nucleus deep brain stimulator adjustment, with a resolution of symptoms and signs when the stimulator was switched off.

  18. [Effects of stimulation of dorso-medial area of nucleus facialis on respiration related units in ventro-lateral region of nucleus tractus solitaris in rabbits].

    PubMed

    Gao, J X; Liu, L

    1990-10-01

    In urethane-anesthetized, vagotomized and paralyzed rabbits, effects of electrical stimulation of the dorso-medial area of the nucleus facialis (DMNF) on the respiration-related units (RRUs) in ventro-lateral region of nucleus tractus solitaris (VLNTS) were observed. The experimental results showed that during electrical stimulation of DMNF the majority of the inspiratory (I) neurons (64.4%) were increased in frequency and duration of discharge, some to a marked extent. During electrical stimulation of DMNF the expiratory neurons (35%) were decreased in their frequency and duration of discharge, some to a marked extent too. The responses of RRUs in ipsilateral and contralateral VLNTS to stimulation of DMNF was not statistically significant (P greater than 0.05). It is suggested that DMNF may have a facilitating effect on the inspiratory neurons and an inhibiting effect on the expiratory neurons in VLNTS.

  19. Subthalamic Nucleus Deep Brain Stimulation Changes Velopharyngeal Control in Parkinson's Disease

    ERIC Educational Resources Information Center

    Hammer, Michael J.; Barlow, Steven M.; Lyons, Kelly E.; Pahwa, Rajesh

    2011-01-01

    Purpose: Adequate velopharyngeal control is essential for speech, but may be impaired in Parkinson's disease (PD). Bilateral subthalamic nucleus deep brain stimulation (STN DBS) improves limb function in PD, but the effects on velopharyngeal control remain unknown. We tested whether STN DBS would change aerodynamic measures of velopharyngeal…

  20. Recording Gamma Band Oscillations in Pedunculopontine Nucleus Neurons.

    PubMed

    Urbano, Francisco J; Luster, Brennon R; D'Onofrio, Stasia; Mahaffey, Susan; Garcia-Rill, Edgar

    2016-09-14

    Synaptic efferents from the PPN are known to modulate the neuronal activity of several intralaminar thalamic regions (e.g., the centrolateral/parafascicular; Cl/Pf nucleus). The activation of either the PPN or Cl/Pf nuclei in vivo has been described to induce the arousal of the animal and an increment in gamma band activity in the cortical electroencephalogram (EEG). The cellular mechanisms for the generation of gamma band oscillations in Reticular Activating System (RAS) neurons are the same as those found to generate gamma band oscillations in other brains nuclei. During current-clamp recordings of PPN neurons (from parasagittal slices from 9 - 25 day-old rats), the use of depolarizing square steps rapidly activated voltage-dependent potassium channels that prevented PPN neurons from being depolarized beyond -25 mV. Injecting 1 - 2 sec long depolarizing current ramps gradually depolarized PPN membrane potential resting values towards 0 mV. However, injecting depolarizing square pulses generated gamma-band oscillations of membrane potential that showed to be smaller in amplitude compared to the oscillations generated by ramps. All experiments were performed in the presence of voltage-gated sodium channels and fast synaptic receptors blockers. It has been shown that the activation of high-threshold voltage-dependent calcium channels underlie gamma-band oscillatory activity in PPN neurons. Specific methodological and pharmacological interventions are described here, providing the necessary tools to induce and sustain PPN subthreshold gamma band oscillation in vitro.

  1. Brain stem stimulation and the acetylcholine-evoked inhibition of neurones in the feline nucleus reticularis thalami

    PubMed Central

    Dingledine, Raymond; Kelly, J. S.

    1977-01-01

    1. In cats anaesthetized with halothane and nitrous oxide, the responses to iontophoretically applied acetylcholine (ACh) and to high-frequency stimulation of the mid-brain reticular formation (MRF) were tested on spontaneously active neurones in the nucleus reticularis thalami and underlying ventrobasal complex. 2. The initial response to MRF stimulation of 90% of the ACh-inhibited neurones found in the region of the dorsolateral nucleus reticularis was an inhibition. Conversely, the initial response of 82% of the ACh-excited neurones in the ventrobasal complex was an excitation. Neurones in the rostral pole of the nucleus reticularis were inhibited by both ACh and RMF stimulation. 3. The mean latency (and s.e. of mean) for the MRF-evoked inhibition was 13·7 ± 3·2 ms (n = 42) and that for the MRF-evoked excitation, 44.1 ± 4.2 ms (n = 35). 4. The ACh-evoked inhibitions were blocked by iontophoretic atropine, in doses that did not block amino acid-evoked inhibition. In twenty-four ACh-inhibited neurones the effect of iontophoretic atropine was tested on MRF-evoked inhibition. In all twenty-four neurones atropine had no effect on the early phase of MRF-evoked inhibition but weakly antagonized the late phase of inhibition in nine of fourteen neurones. 5. Interspike-interval histograms showed that the firing pattern of neurones in the nucleus reticularis was characterized by periods of prolonged, high-frequency bursting. Both the ACh-evoked inhibitions and the late phase of MRF-evoked inhibitions were accompanied by an increased burst activity. In contrast, iontophoretic atropine tended to suppress burst activity. 6. The possibility is discussed that electrical stimulation of the MRF activates an inhibitory cholinergic projection to the nucleus reticularis. Since neurones of the nucleus reticularis have been shown to inhibit thalamic relay cells, activation of this inhibitory pathway may play a role in MRF-evoked facilitation of thalamo-cortical relay transmission

  2. Subthalamic nucleus deep brain stimulation for Parkinson's disease: evidence for effectiveness and limitations from 12 years' experience.

    PubMed

    Chan, Anne Y Y; Yeung, Jonas H M; Mok, Vincent C T; Ip, Vincent H L; Wong, Adrian; Kuo, S H; Chan, Danny T M; Zhu, X L; Wong, Edith; Lau, Claire K Y; Wong, Rosanna K M; Tang, Venus; Lau, Christine; Poon, W S

    2014-12-01

    To present the result and experience of subthalamic nucleus deep brain stimulation for Parkinson's disease. Case series. Prince of Wales Hospital, Hong Kong. A cohort of patients with Parkinson's disease received subthalamic nucleus deep brain stimulation from September 1998 to January 2010. Patient assessment data before and after the operation were collected prospectively. Forty-one patients (21 male and 20 female) with Parkinson's disease underwent bilateral subthalamic nucleus deep brain stimulation and were followed up for a median interval of 12 months. For the whole group, the mean improvements of Unified Parkinson's Disease Rating Scale (UPDRS) parts II and III were 32.5% and 31.5%, respectively (P<0.001). Throughout the years, a multidisciplinary team was gradually built. The deep brain stimulation protocol evolved and was substantiated by updated patient selection criteria and outcome assessment, integrated imaging and neurophysiological targeting, refinement of surgical technique as well as the accumulation of experience in deep brain stimulation programming. Most of the structural improvement occurred before mid-2005. Patients receiving the operation before June 2005 (19 cases) and after (22 cases) were compared; the improvements in UPDRS part III were 13.2% and 55.2%, respectively (P<0.001). There were three operative complications (one lead migration, one cerebral haematoma, and one infection) in the group operated on before 2005. There was no operative mortality. The functional state of Parkinson's disease patients with motor disabilities refractory to best medical treatment improved significantly after subthalamic nucleus deep brain stimulation. A dedicated multidisciplinary team building, refined protocol for patient selection and assessment, improvement of targeting methods, meticulous surgical technique, and experience in programming are the key factors contributing to the improved outcome.

  3. PET Mapping for Brain-Computer Interface Stimulation of the Ventroposterior Medial Nucleus of the Thalamus in Rats with Implanted Electrodes.

    PubMed

    Zhu, Yunqi; Xu, Kedi; Xu, Caiyun; Zhang, Jiacheng; Ji, Jianfeng; Zheng, Xiaoxiang; Zhang, Hong; Tian, Mei

    2016-07-01

    Brain-computer interface (BCI) technology has great potential for improving the quality of life for neurologic patients. This study aimed to use PET mapping for BCI-based stimulation in a rat model with electrodes implanted in the ventroposterior medial (VPM) nucleus of the thalamus. PET imaging studies were conducted before and after stimulation of the right VPM. Stimulation induced significant orienting performance. (18)F-FDG uptake increased significantly in the paraventricular thalamic nucleus, septohippocampal nucleus, olfactory bulb, left crus II of the ansiform lobule of the cerebellum, and bilaterally in the lateral septum, amygdala, piriform cortex, endopiriform nucleus, and insular cortex, but it decreased in the right secondary visual cortex, right simple lobule of the cerebellum, and bilaterally in the somatosensory cortex. This study demonstrated that PET mapping after VPM stimulation can identify specific brain regions associated with orienting performance. PET molecular imaging may be an important approach for BCI-based research and its clinical applications. © 2016 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

  4. Deep brain stimulation of the subthalamic nucleus modulates sensitivity to decision outcome value in Parkinson’s disease

    NASA Astrophysics Data System (ADS)

    Seymour, Ben; Barbe, Michael; Dayan, Peter; Shiner, Tamara; Dolan, Ray; Fink, Gereon R.

    2016-09-01

    Deep brain stimulation (DBS) of the subthalamic nucleus in Parkinson’s disease is known to cause a subtle but important adverse impact on behaviour, with impulsivity its most widely reported manifestation. However, precisely which computational components of the decision process are modulated is not fully understood. Here we probe a number of distinct subprocesses, including temporal discount, outcome utility, instrumental learning rate, instrumental outcome sensitivity, reward-loss trade-offs, and perseveration. We tested 22 Parkinson’s Disease patients both on and off subthalamic nucleus deep brain stimulation (STN-DBS), while they performed an instrumental learning task involving financial rewards and losses, and an inter-temporal choice task for financial rewards. We found that instrumental learning performance was significantly worse following stimulation, due to modulation of instrumental outcome sensitivity. Specifically, patients became less sensitive to decision values for both rewards and losses, but without any change to the learning rate or reward-loss trade-offs. However, we found no evidence that DBS modulated different components of temporal impulsivity. In conclusion, our results implicate the subthalamic nucleus in a modulation of outcome value in experience-based learning and decision-making in Parkinson’s disease, suggesting a more pervasive role of the subthalamic nucleus in the control of human decision-making than previously thought.

  5. Deep brain stimulation of the subthalamic nucleus modulates sensitivity to decision outcome value in Parkinson’s disease

    PubMed Central

    Seymour, Ben; Barbe, Michael; Dayan, Peter; Shiner, Tamara; Dolan, Ray; Fink, Gereon R.

    2016-01-01

    Deep brain stimulation (DBS) of the subthalamic nucleus in Parkinson’s disease is known to cause a subtle but important adverse impact on behaviour, with impulsivity its most widely reported manifestation. However, precisely which computational components of the decision process are modulated is not fully understood. Here we probe a number of distinct subprocesses, including temporal discount, outcome utility, instrumental learning rate, instrumental outcome sensitivity, reward-loss trade-offs, and perseveration. We tested 22 Parkinson’s Disease patients both on and off subthalamic nucleus deep brain stimulation (STN-DBS), while they performed an instrumental learning task involving financial rewards and losses, and an inter-temporal choice task for financial rewards. We found that instrumental learning performance was significantly worse following stimulation, due to modulation of instrumental outcome sensitivity. Specifically, patients became less sensitive to decision values for both rewards and losses, but without any change to the learning rate or reward-loss trade-offs. However, we found no evidence that DBS modulated different components of temporal impulsivity. In conclusion, our results implicate the subthalamic nucleus in a modulation of outcome value in experience-based learning and decision-making in Parkinson’s disease, suggesting a more pervasive role of the subthalamic nucleus in the control of human decision-making than previously thought. PMID:27624437

  6. Deep Brain Stimulation to Alleviate Freezing of Gait and Cognitive Dysfunction in Parkinson's Disease: Update on Current Research and Future Perspectives.

    PubMed

    Huang, Chuyi; Chu, Heling; Zhang, Yan; Wang, Xiaoping

    2018-01-01

    Freezing of gait (FOG) is a gait disorder featured by recurrent episodes of temporary gait halting and mainly found in advanced Parkinson's disease (PD). FOG has a severe impact on the quality of life of patients with PD. The pathogenesis of FOG is unclear and considered to be related to several brain areas and neural circuits. Its close connection with cognitive disorder has been proposed and some researchers explain the pathogenesis using the cognitive model theory. FOG occurs concurrently with cognitive disorder in some PD patients, who are poorly responsive to medication therapy. Deep brain stimulation (DBS) proves effective for FOG in PD patients. Cognitive impairment plays a role in the formation of FOG. Therefore, if DBS works by improving the cognitive function, both two challenging conditions can be ameliorated by DBS. We reviewed the clinical studies related to DBS for FOG in PD patients over the past decade. In spite of the varying stimulation parameters used in different studies, DBS of either subthalamic nucleus (STN) or pedunculopontine nucleus (PPN) alone or in combination can improve the symptoms of FOG. Moreover, the treatment efficacy can last for 1-2 years and DBS is generally safe. Although few studies have been conducted concerning the use of DBS for cognitive disorder in FOG patients, the existing studies seem to indicate that PPN is a potential therapeutic target to both FOG and cognitive disorder. However, most of the studies have a small sample size and involve sporadic cases, so it remains uncertain which nucleus is the optimal target of stimulation. Prospective clinical trials with a larger sample size are needed to systematically assess the efficacy of DBS for FOG and cognitive disorder.

  7. Cardiorespiratory responses to stimulation of the nucleus reticularis gigantocellularis.

    PubMed

    Stremel, R W; Waldrop, T G; Richard, C A; Iwamoto, G A

    1990-01-01

    The nucleus reticularis gigantocellularis (NGC) has been shown to be involved in somatosensory and somatomotor functions. The purpose of the present study was to determine, in anesthetized cats, the modulatory influence of the portion of the NGC at the ponto-medullary border on respiratory and cardiovascular control. Electrical stimulation (25-100 microA 70 Hz, and 1.0-msec pulse duration) significantly depressed mean arterial pressure, heart rate, breathing frequency, tidal volume and phrenic amplitude. Chemical stimulation of NGC cell bodies (1.0 M L-glutamate or 10(-3) M kainic acid) elicited similar decreases in ventilation, arterial pressure and heart rate. These results show that selective activation of cell bodies in the ponto-medullary NGC can depress, in parallel, respiratory and cardiovascular activity and suggests that the influence of diverse sensory information within this region of the reticular formation must be inhibitory to respiratory and cardiovascular output.

  8. Microinfusion of nefazodone into the basolateral nucleus of the amygdala enhances defensive behavior induced by NMDA stimulation of the inferior colliculus.

    PubMed

    Maisonnette, S; Villela, C; Carotti, A P; Landeira-Fernandez, J

    2000-01-01

    The inferior colliculus is notably associated with defensive behavior. Electrical or pharmacological stimulation of the inferior colliculus induces aversive reactions such as running and jumping. Lesion of the basolateral nucleus of the amygdala decreases the threshold of aversive reactions induced by electrical stimulation of the inferior colliculus. The present work examined the influence of microinjections of nefazodone, a serotonin (5-HT(2)) antagonist, into the basolateral nucleus of amygdala on aversive reactions induced by N-methyl-D-aspartate (NMDA) microinjected into the inferior colliculus. Rats implanted with cannulae in the inferior colliculus and in the basolateral nucleus of the amygdala were submitted to the open-field test where defensive behaviors were observed. Results indicated that microinjection of nefazodone into the basolateral nucleus of the amygdala increases aversive responses induced by NMDA injections into the inferior colliculus. This result suggests that the inferior colliculus and the basolateral nucleus of the amygdala have a functional relationship on the neural circuitry of defensive behavior. Moreover, 5-HT(2) receptors located at the basolateral nucleus of the amygdala seem to play an inhibitory role on defensive behaviors induced by inferior colliculus stimulation.

  9. Effects of Nucleus Basalis Magnocellularis Stimulation on a Socially Transmitted Food Preference and c-Fos Expression

    ERIC Educational Resources Information Center

    Boix-Trelis, Nuria; Vale-Martinez, Anna; Guillazo-Blanch, Gemma; Costa-Miserachs, David; Marti-Nicolovius, Margarita

    2006-01-01

    Experiment 1 examined the effects of electrical stimulation of nucleus basalis magnocellularis (NBM) on a relational odor-association task--the social transmission of food preference (STFP). Rats were stimulated unilaterally in the NBM for 20 min (100 [mu]A, 1 Hz) immediately before the social training. They were tested on their ability to…

  10. Clinical evaluation of higher stimulation rates in the nucleus research platform 8 system.

    PubMed

    Plant, Kerrie; Holden, Laura; Skinner, Margo; Arcaroli, Jennifer; Whitford, Lesley; Law, Mary-Ann; Nel, Esti

    2007-06-01

    The effect on speech perception of using higher stimulation rates than the 14.4 kHz available in the Nucleus 24 cochlear implant system was investigated. The study used the Nucleus Research Platform 8 (RP8) system, comprising the CI24RE receiver-stimulator with the Contour electrode array, the L34SP body-worn research speech processor, and the Nucleus Programming Environment (NPE) fitting and Neural Response Telemetry (NRT) software. This system enabled clinical investigation of higher stimulation rates before an implementation in the Freedom cochlear implant system commercially released by Cochlear Limited. Use of higher stimulation rates in the ACE coding strategy was assessed in 15 adult subjects. An ABAB experimental design was used to control for order effects. Program A used a total stimulation rate of between 12 kHz and 14.4 kHz. This program was used for at least the first 3 mo after initial device activation. After evaluation with this program, each subject was provided with two different higher stimulation rate programs: one with a total stimulation rate of 24 kHz and the other with a total stimulation rate of 32 kHz. After a 6-week period of familiarization, each subject identified his/her preferred higher rate program (program B), and this was used for the evaluation. Subjects then repeated their use of program A for 3 wk, then program B for 3 wk, before the second evaluation with each. Speech perception was evaluated by using CNC open-set monosyllabic words presented in quiet and CUNY open-set sentences presented in noise. Preference for stimulation rate program was assessed via a subjective questionnaire. Threshold (T)- and Comfortable (C)-levels, as well as subjective reports of tinnitus, were monitored for each subject throughout the study to determine whether there were any changes that might be associated with the use of higher stimulation rates. No significant mean differences in speech perception results were found for the group between the two

  11. Subthalamic nucleus deep brain stimulation affects distractor interference in auditory working memory.

    PubMed

    Camalier, Corrie R; Wang, Alice Y; McIntosh, Lindsey G; Park, Sohee; Neimat, Joseph S

    2017-03-01

    Computational and theoretical accounts hypothesize the basal ganglia play a supramodal "gating" role in the maintenance of working memory representations, especially in preservation from distractor interference. There are currently two major limitations to this account. The first is that supporting experiments have focused exclusively on the visuospatial domain, leaving questions as to whether such "gating" is domain-specific. The second is that current evidence relies on correlational measures, as it is extremely difficult to causally and reversibly manipulate subcortical structures in humans. To address these shortcomings, we examined non-spatial, auditory working memory performance during reversible modulation of the basal ganglia, an approach afforded by deep brain stimulation of the subthalamic nucleus. We found that subthalamic nucleus stimulation impaired auditory working memory performance, specifically in the group tested in the presence of distractors, even though the distractors were predictable and completely irrelevant to the encoding of the task stimuli. This study provides key causal evidence that the basal ganglia act as a supramodal filter in working memory processes, further adding to our growing understanding of their role in cognition. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. The MDS-UPDRS tracks motor and non-motor improvement due to subthalamic nucleus deep brain stimulation in Parkinson disease.

    PubMed

    Chou, Kelvin L; Taylor, Jennifer L; Patil, Parag G

    2013-11-01

    The Movement Disorders Society revision of the Unified Parkinson Disease Rating Scale (MDS-UPDRS) improves upon the original UPDRS by adding more non-motor items, making it a more robust tool to evaluate the severity of motor and non-motor symptoms of Parkinson disease. Previous studies on deep brain stimulation have not used the MDS-UPDRS. To determine if the MDS-UPDRS could detect improvement in both motor and non-motor symptoms after bilateral subthalamic nucleus deep brain stimulation for Parkinson disease. We compared scores on the entire MDS-UPDRS prior to surgery (baseline) and approximately six months following the initial programming visit in twenty subjects (12M/8F) with Parkinson disease undergoing bilateral subthalamic nucleus deep brain stimulation. STN DBS significantly improved the scores for every section of the MDS-UPDRS at the 6 month follow-up. Part I improved by 3.1 points (22%), Part II by 5.3 points (29%), Part III by 13.1 points (29%) with stimulation alone, and Part IV by 7.1 points (74%). Individual non-motor items in Part I that improved significantly were constipation, light-headedness, and fatigue. Both motor and non-motor symptoms, as assessed by the MDS-UPDRS, improve with bilateral subthalamic nucleus stimulation six months after the stimulator is turned on. We recommend that the MDS-UPDRS be utilized in future deep brain stimulation studies because of the advantage of detecting change in non-motor symptoms. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Interactions between rewarding lateral hypothalamic and aversive nucleus reticularis gigantocellularis stimulation.

    PubMed

    Diotte, M; Miguelez, M; Miliaressis, E; Bielajew, C

    2000-12-05

    The interaction between rewarding and aversive consequences of brain stimulation were assessed in two studies. In the first, the frequency threshold for 300 ms trains of combined lateral hypothalamic (LH) and nucleus reticularis gigantocellularis (Gi) stimulation, in which each LH pulse was followed 2 ms later by the Gi one, was determined for one month. Compared to the threshold for trains of single LH pulses, combined LH-Gi stimulation initially increased the frequency threshold; however, this effect reversed within one session and was subsequently maintained for the duration of the study. The aversion produced by Gi stimulation, as measured by latency to escape, was abolished following a single session of LH-Gi pairs. In the second study, a subset of animals received both presentations of combined pulses, LH followed by Gi, and the reverse; the interval between pulses was varied from 0.2 to 6.4 ms. The effectiveness of combined stimulation, determined by the ratio of LH frequency thresholds to that of the LH-Gi ranged from 0 to 50% across animals but the individual effectiveness functions within animals did not vary with different intervals. In addition, the order of presentation of pulses was of no consequence. Thus, not only did exposure to LH stimulation appear to obliterate Gi aversion, but the combination of LH and Gi pulses added to the rewarding effect produced by LH stimulation alone.

  14. Deep brain stimulation of nucleus accumbens region in alcoholism affects reward processing.

    PubMed

    Heldmann, Marcus; Berding, Georg; Voges, Jürgen; Bogerts, Bernhard; Galazky, Imke; Müller, Ulf; Baillot, Gunther; Heinze, Hans-Jochen; Münte, Thomas F

    2012-01-01

    The influence of bilateral deep brain stimulation (DBS) of the nucleus nucleus (NAcc) on the processing of reward in a gambling paradigm was investigated using H(2)[(15)O]-PET (positron emission tomography) in a 38-year-old man treated for severe alcohol addiction. Behavioral data analysis revealed a less risky, more careful choice behavior under active DBS compared to DBS switched off. PET showed win- and loss-related activations in the paracingulate cortex, temporal poles, precuneus and hippocampus under active DBS, brain areas that have been implicated in action monitoring and behavioral control. Except for the temporal pole these activations were not seen when DBS was deactivated. These findings suggest that DBS of the NAcc may act partially by improving behavioral control.

  15. Familiar companions diminish cocaine conditioning and attenuate cocaine-stimulated dopamine release in the nucleus accumbens.

    PubMed

    Tzeng, Wen-Yu; Cherng, Chian-Fang G; Wang, Shyi-Wu; Yu, Lung

    2016-06-01

    This study aimed to assess the impact of companions on the rewarding effects of cocaine. Three cage mates, serving as companions, were housed with each experimental mouse throughout cocaine-place conditioning in a cocaine-induced conditioned place preference (CPP) paradigm using conditioning doses of 10 and 20mg/kg. The presence of companions decreased the magnitude of the CPP. At 20mg/kg, cocaine stimulated dopamine (DA) release in the nucleus accumbens as evidenced by a significant decrease in total (spontaneous and electrical stimulation-provoked) DA release in accumbal superfusate samples. The presence of companions prevented this cocaine-stimulated DA release; such a reduction in cocaine-induced DA release may account for the reduction in the magnitude of the CPP in the presence of the companions. Furthermore, cocaine pretreatment (2.5mg/kg) was found to prevent the companion-produced decreases in cocaine (10mg/kg/conditioning)-induced CPP as well as the cocaine (10mg/kg)-stimulated DA release. Moreover, the presence of methamphetamine (MA) (1mg/kg)-treated companions decreased cocaine (20mg/kg/conditioning)-induced CPP and prevented the cocaine (20mg/kg)-stimulated DA release. Finally, the presence of companions decreased the magnitude of the CPP could not seem to be accounted for by cocaine-stimulated corticosterone (CORT) release. Taken together, these results indicate that familiar companions, regardless of their pharmacological status, may exert dampening effects on CPP induced by moderate to high conditioning doses of cocaine, at least in part, by preventing cocaine-stimulated DA release in the nucleus accumbens. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Complications of subthalamic nucleus stimulation in Parkinson's disease.

    PubMed

    Umemura, Atsushi; Oka, Yuichi; Yamamoto, Kenichi; Okita, Kenji; Matsukawa, Noriyuki; Yamada, Kazuo

    2011-01-01

    Subthalamic nucleus deep brain stimulation (STN-DBS) is effective for medically refractory Parkinson's disease. We retrospectively analyzed complications in 180 consecutive patients who underwent bilateral STN-DBS. Surgery-related complications were symptomatic intracerebral hemorrhage in 2, chronic subdural hematoma in 1, and transient deterioration of medication-induced psychosis in 2 patients. Device-related complications involved device infection in 5, skin erosion in 5, and implantable pulse generator malfunction in 2 patients. All of these patients required surgical repair. Surgery and device-related complications could be reduced with increased surgical experience and the introduction of new surgical equipment and technology. Treatment or stimulation-related complications were intractable dyskinesia/dystonia in 11, problematic dysarthria in 7, apraxia of eyelid opening (ALO) in 11, back pain in 10, and restless leg syndrome in 6 patients. Neuropsychiatric complications were transient mood changes in some, impulse control disorder in 2, severe depression related to excessive reduction of dopaminergic medications in 2, rapid progression of dementia in 1, and suicide attempts in 2 patients. Most complications were mild and transient. Dysarthria and ALO were the most frequent permanent sequelae after STN-DBS. Treatment-related adverse events may be caused not only by the effect of stimulation effect but also excessive reduction of dopaminergic medication, or progression of the disease. In conclusion, STN-DBS seems to be a relatively safe procedure. Although serious complications with permanent sequelae are rare, significant incidences of adverse effects occur. Physicians engaged in this treatment should have a comprehensive understanding of the probable complications and how to avoid them.

  17. Subthalamic nucleus stimulation and spontaneous language production in Parkinson's disease: A double laterality problem.

    PubMed

    Batens, Katja; De Letter, Miet; Raedt, Robrecht; Duyck, Wouter; Vanhoutte, Sarah; Van Roost, Dirk; Santens, Patrick

    2015-08-01

    Asymmetric degeneration of dopaminergic neurons, are characteristic for Parkinson's disease (PD). Despite the lateralized representation of language, the correlation of asymmetric degeneration of nigrostriatal networks in PD with language performance has scarcely been examined. The laterality of dopamine depletion influences language deficits in PD and thus modulates the effects of subthalamic nucleus (STN) stimulation on language production. The spontaneous language production of patients with predominant dopamine depletion of the left (PD-left) and right (PD-right) hemisphere was compared in four stimulation conditions. PD-right made comparatively more verb inflection errors than PD-left. Bilateral STN stimulation improves spontaneous language production only for PD-left. The laterality of dopamine depletion influences spontaneous language production and the effect of STN stimulation on linguistic functions. However, it is probably only one of the many variables influencing the effect of STN stimulation on language production. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Zinc release in the lateral nucleus of the amygdala by stimulation of the entorhinal cortex.

    PubMed

    Takeda, Atsushi; Imano, Sachie; Itoh, Hiromasa; Oku, Naoto

    2006-11-06

    Zinc release in the lateral nucleus of the amygdala was examined using rat brain slices. The lateral and basolateral nuclei in the amygdala were evidently stained by Timm's sulfide-silver staining method. When the amygdala including both the nuclei was stimulated with 100 mM KCl by means of in vivo microdialysis, extracellular zinc concentration was increased significantly. Zinc release in the lateral nucleus of the amygdala innervated by the entorhinal cortex was next examined in brain slices double-stained with zinc and calcium indicators. Extracellular zinc signal (ZnAF-2) in the lateral nucleus was increased with intracellular calcium signal (calcium orange) during delivery of tetanic stimuli to the entorhinal cortex. Both the increases were completely inhibited by addition of 1 micro M tetrodotoxin, a sodium channel blocker. Furthermore, calcium signal in the lateral nucleus during delivery of tetanic stimuli to the entorhinal cortex was increased in the presence of 10 micro M CNQX, an AMPA/KA receptor antagonist, and this increase was facilitated by addition of 1 mM CaEDTA, a membrane-impermeable zinc chelator. The present study suggested that zinc is released in the lateral nucleus of the amygdala by depolarization of the entorhinal neurons. In the lateral nucleus, zinc released may suppress the increase in presynaptic calcium signal.

  19. Excitatory innervation of caudal hypoglossal nucleus from nucleus reticularis gigantocellularis in the rat.

    PubMed

    Yang, C C; Chan, J Y; Chan, S H

    1995-03-01

    We examined the possible innervation of the caudal hypoglossal nucleus by the nucleus reticularis gigantocellularis of the medulla oblongata, based on single-neuron recording and retrograde tracing experiments in Sprague-Dawley rats. Under pentobarbital sodium (50 mg/kg, i.p.) anesthesia, electrical stimulation of the caudal portion of the nucleus reticularis gigantocellularis with repetitive 0.5-ms rectangular pulses increased (46 of 51 neurons) the basal discharge frequency of spontaneously active cells, or evoked spike activity in silent, hypoglossal neurons located at the level of the obex. This excitatory effect was related to the intensity (25-100 microA) and/or frequency (0.5-20 Hz) of the stimulating pulses to the nucleus reticularis gigantocellularis. Perikaryal activation of neurons by microinjection of L-glutamate (0.5 nmol, 25 nl) into the caudal portion of the nucleus reticularis gigantocellularis similarly produced an excitatory action on eight of 14 hypoglossal neurons. Retrogradely labeled neurons were found bilaterally within the confines of the nucleus reticularis gigantocellularis following unilateral microinjection of wheatgerm agglutinin-conjugated horseradish peroxidase or Fast Blue into the corresponding hypoglossal recording sites. Furthermore, the distribution of labeled neurons in the nucleus reticularis gigantocellularis substantially overlapped with the loci of electrical or chemical stimulation. These complementary electrophysiological and neuroanatomical results support the conclusion that an excitatory link exists between the nucleus reticularis gigantocellularis and at least the caudal portion of the hypoglossal nucleus in the rat.

  20. Cortical Plasticity Induction by Pairing Subthalamic Nucleus Deep-Brain Stimulation and Primary Motor Cortical Transcranial Magnetic Stimulation in Parkinson's Disease.

    PubMed

    Udupa, Kaviraja; Bahl, Nina; Ni, Zhen; Gunraj, Carolyn; Mazzella, Filomena; Moro, Elena; Hodaie, Mojgan; Lozano, Andres M; Lang, Anthony E; Chen, Robert

    2016-01-13

    Noninvasive brain stimulation studies have shown abnormal motor cortical plasticity in Parkinson's disease (PD). These studies used peripheral nerve stimulation paired with transcranial magnetic stimulation (TMS) to primary motor cortex (M1) at specific intervals to induce plasticity. Induction of cortical plasticity through stimulation of the basal ganglia (BG)-M1 connections has not been studied. In the present study, we used a novel technique of plasticity induction by repeated pairing of deep-brain stimulation (DBS) of the BG with M1 stimulation using TMS. We hypothesize that repeated pairing of subthalamic nucleus (STN)-DBS and M1-TMS at specific time intervals will lead to plasticity in the M1. Ten PD human patients with STN-DBS were studied in the on-medication state with DBS set to 3 Hz. The interstimulus intervals (ISIs) between STN-DBS and TMS that produced cortical facilitation were determined individually for each patient. Three plasticity induction conditions with repeated pairings (180 times) at specific ISIs (∼ 3 and ∼ 23 ms) that produced cortical facilitation and a control ISI of 167 ms were tested in random order. Repeated pairing of STN-DBS and M1-TMS at short (∼ 3 ms) and medium (∼ 23 ms) latencies increased M1 excitability that lasted for at least 45 min, whereas the control condition (fixed ISI of 167 ms) had no effect. There were no specific changes in motor thresholds, intracortical circuits, or recruitment curves. Our results indicate that paired-associative cortical plasticity can be induced by repeated STN and M1 stimulation at specific intervals. These results show that STN-DBS can modulate cortical plasticity. We introduced a new experimental paradigm to test the hypothesis that pairing subthalamic nucleus deep-brain stimulation (STN-DBS) with motor cortical transcranial magnetic stimulation (M1-TMS) at specific times can induce cortical plasticity in patients with Parkinson's disease (PD). We found that repeated pairing of STN

  1. [EFFECTS OF ELECTRICAL STIMULATION OF NUCLEUS RETICULARIS PONTIS ORALIS ON THE SLEEP-WAKING STATES IN KRUSHINSKII-MOLODKINA STRAIN RATS].

    PubMed

    Vataev, S I; Malgina, N A; Oganesyan, G A

    2015-07-01

    The effects of electrical stimulation of nucleus reticularis pontis oralis on the behavior and brain electrical activity during all phases of the sleep-waking cycle was studied in Krushinskii-Molodkina strain rats, which have an inherited predisposition to audiogenic seizures. Electrical stimulation with 7 Hz frequency in the deep stage of slow-wave sleep cause appearance the fast-wave sleep. Similar stimulation during fast-wave sleep periods did not effects on the electrographic patterns and EEG spectral characteristics of hippocampus, visual, auditory and somatocnen nrnrenc nf the cnrtey ThPe sfimul1stinns did nnt break a fast-wave sleenhut increased almost twice due the duration of these sleep episodes. After electrical stimulation by same frequency during the wakeftlness and superficial slow-wave sleep states, the patterns and spectral characteristics of brain electrical activity in rats showed no significant changes as compared with controls. The results of this study indicate that the state of the animals sleep-waking cycle at the time of stimulation is a critical variable that influences the responses which are induced by electrical stimulation of the nucleus reticularis pontis oralis.

  2. Deep brain stimulation in the central nucleus of the amygdala decreases 'wanting' and 'liking' of food rewards.

    PubMed

    Ross, Shani E; Lehmann Levin, Emily; Itoga, Christy A; Schoen, Chelsea B; Selmane, Romeissa; Aldridge, J Wayne

    2016-10-01

    We investigated the potential of deep brain stimulation (DBS) in the central nucleus of the amygdala (CeA) in rats to modulate functional reward mechanisms. The CeA is the major output of the amygdala with direct connections to the hypothalamus and gustatory brainstem, and indirect connections with the nucleus accumbens. Further, the CeA has been shown to be involved in learning, emotional integration, reward processing, and regulation of feeding. We hypothesized that DBS, which is used to treat movement disorders and other brain dysfunctions, might block reward motivation. In rats performing a lever-pressing task to obtain sugar pellet rewards, we stimulated the CeA and control structures, and compared stimulation parameters. During CeA stimulation, animals stopped working for rewards and rejected freely available rewards. Taste reactivity testing during DBS exposed aversive reactions to normally liked sucrose tastes and even more aversive taste reactions to normally disliked quinine tastes. Interestingly, given the opportunity, animals implanted in the CeA would self-stimulate with 500 ms trains of stimulation at the same frequency and current parameters as continuous stimulation that would stop reward acquisition. Neural recordings during DBS showed that CeA neurons were still active and uncovered inhibitory-excitatory patterns after each stimulus pulse indicating possible entrainment of the neural firing with DBS. In summary, DBS modulation of CeA may effectively usurp normal neural activity patterns to create an 'information lesion' that not only decreased motivational 'wanting' of food rewards, but also blocked 'liking' of rewards. © 2016 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  3. Remission of alcohol dependency following deep brain stimulation of the nucleus accumbens: valuable therapeutic implications?

    PubMed Central

    Kuhn, Jens; Lenartz, Doris; Huff, Wolfgang; Lee, Sun-Hee; Koulousakis, Athanasios; Klosterkoetter, Joachim; Sturm, Volker

    2009-01-01

    Chronic consumption of alcohol represents one of the greatest health and socioeconomic problems worldwide. We report on a 54-year-old patient with a severe anxiety disorder and secondary depressive disorder in whom bilateral deep brain stimulation (DBS) of the nucleus accumbens was carried out. Despite the absence of desired improvement in his primary disorder, we observed a remarkable although not primarily intended alleviation of the patient’s comorbid alcohol dependency. Our case report demonstrates the extremely effective treatment of alcohol dependency by means of DBS of the nucleus accumbens and may reveal new prospects in overcoming therapy resistance in dependencies in general. PMID:21686755

  4. Stimulation Induced Electrographic Seizures in Deep Brain Stimulation of the Anterior Nucleus of the Thalamus Do Not Preclude a Subsequent Favorable Treatment Response.

    PubMed

    Nora, Tommi; Heinonen, Hanna; Tenhunen, Mirja; Rainesalo, Sirpa; Järvenpää, Soila; Lehtimäki, Kai; Peltola, Jukka

    2018-01-01

    Deep brain stimulation (DBS) of the anterior nucleus of the thalamus (ANT) is a method of neuromodulation used for refractory focal epilepsy. We report a patient suffering from drug-resistant epilepsy who developed novel visual symptoms and atypical seizures with the onset of ANT-DBS therapy. Rechallenge under video electroencephalography recording confirmed that lowering the stimulation voltage alleviated these symptoms. Subsequent stimulation with the initial voltage value did not cause the recurrence of either the visual symptoms or the new seizure type, and appeared to alleviate the patient's seizures in long-term follow-up. We therefore hypothesize that the occurrence of stimulation induced seizures at the onset of DBS therapy should not be considered as a failure in the DBS therapy, and the possibility of a subsequent favorable response to the treatment still exists.

  5. Articulation Features of Parkinson's Disease Patients with Subthalamic Nucleus Deep Brain Stimulation.

    PubMed

    Tanaka, Yasuhiro; Tsuboi, Takashi; Watanabe, Hirohisa; Kajita, Yasukazu; Nakatsubo, Daisuke; Fujimoto, Yasushi; Ohdake, Reiko; Ito, Mizuki; Atsuta, Naoki; Yamamoto, Masahiko; Wakabayashi, Toshihiko; Katsuno, Masahisa; Sobue, Gen

    2016-10-19

    Voice and speech disorders are one of the most important issues after subthalamic nucleus deep brain stimulation (STN-DBS) in Parkinson's disease (PD) patients. However, articulation features in this patient population remain unclear. We studied the articulation features of PD patients with STN-DBS. Participants were 56 PD patients treated with STN-DBS (STN-DBS group) and 41 patients treated only with medical therapy (medical-therapy-alone group). Articulation function was evaluated with acoustic and auditory-perceptual analyses. The vowel space area (VSA) was calculated using the formant frequency data of three vowels (/a/, /i/, and /u/) from sustained phonation task. The VSA reportedly reflects the distance of mouth/jaw and tongue movements during speech and phonation. Correlations between acoustic and auditory-perceptual measurements were also assessed. The VSA did not significantly differ between the medical-therapy-alone group and the STN-DBS group in the off-stimulation condition. In the STN-DBS group, the VSA was larger in the on-stimulation condition than in the off-stimulation condition. However, individual analysis showed the VSA changes after stopping stimulation were heterogeneous. In total, 89.8% of the STN-DBS group showed a large VSA size in the on- than in the off-stimulation condition. In contrast, the VSA of the remaining patients in that group was smaller in the on- than the off-stimulation condition. STN-DBS may resolve hypokinesia of the articulation structures, including the mouth/jaw and tongue, and improve maximal vowel articulation. However, in the on-stimulation condition, the VSA was not significantly correlated with speech intelligibility. This may be because STN-DBS potentially affects other speech processes such as voice and/or respiratory process.

  6. [Effects of electric stimulation at the cerebellar fastigial nucleus on astrocytes in the hippocampus of neonatal rats with hypoxic-ischemic brain damage].

    PubMed

    Li, Xiao-Li; Jia, Tian-Ming; Luan, Bin; Liu, Tao; Yuan, Yan

    2011-04-01

    To study the effects of electric stimulation at the cerebellar fastigial nucleus on astrocytes in the hippocampus of neonatal rats with hypoxic-ischemic brain damage (HIBD) and the possible mechanism. One hundred and eighty 7-day-old neonatal Sprague-Dawley rats were randomly divided into three groups: sham-operation (control group) and HIBD with and without electric stimulation (n=60 each). The HIBD model of neonatal rats was prepared by the Rice-Vennucci method. Electric stimulation at the cerebellar fastigial nucleus was given 24 hrs after the operation in the electric stimulation group once daily and lasted for 30 minutes each time. The other two groups were not subjected to electric stimulation but captured to fix in corresponding periods. Rats were sacrificed 3, 7, 14 and 21 days after stimulations to observe the glial fibrillary acidic protein (GFAP) expression by immunohistochemisty and the ultrastructural changes of astrocytes in the hippocampus under an electron microscope. Immunohistochemical analysis showed the expression of GFAP in the HIBD groups with and without electric stimulation increased significantly compared with the control group on day 3, reached the peak on day 7, and the increased expression remained till to day 21. The GFAP expression in the electric stimulation group was significantly lower than that in the untreated HIBD group at all time points. Under the electron microscope, the astrocytes in the untreated HIBD group were swollen and the amount of organelles was reduced, while the swelling of astrocytes was alleviated and the organelles remained in integrity in the electric stimulation group. The electric stimulation at the cerebellar fastigial nucleus can inhibit the excessive proliferation of astrocytes and relieve the structural damage of astrocytes in neonatal rats following HIBD.

  7. Dynamic stereotypic responses of Basal Ganglia neurons to subthalamic nucleus high-frequency stimulation in the parkinsonian primate.

    PubMed

    Moran, Anan; Stein, Edward; Tischler, Hadass; Belelovsky, Katya; Bar-Gad, Izhar

    2011-01-01

    Deep brain stimulation (DBS) in the subthalamic nucleus (STN) is a well-established therapy for patients with severe Parkinson's disease (PD); however, its mechanism of action is still unclear. In this study we explored static and dynamic activation patterns in the basal ganglia (BG) during high-frequency macro-stimulation of the STN. Extracellular multi-electrode recordings were performed in primates rendered parkinsonian using 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine. Recordings were preformed simultaneously in the STN and the globus pallidus externus and internus. Single units were recorded preceding and during the stimulation. During the stimulation, STN mean firing rate dropped significantly, while pallidal mean firing rates did not change significantly. The vast majority of neurons across all three nuclei displayed stimulation driven modulations, which were stereotypic within each nucleus but differed across nuclei. The predominant response pattern of STN neurons was somatic inhibition. However, most pallidal neurons demonstrated synaptic activation patterns. A minority of neurons across all nuclei displayed axonal activation. Temporal dynamics were observed in the response to stimulation over the first 10 seconds in the STN and over the first 30 seconds in the pallidum. In both pallidal segments, the synaptic activation response patterns underwent delay and decay of the magnitude of the peak response due to short term synaptic depression. We suggest that during STN macro-stimulation the STN goes through a functional ablation as its upper bound on information transmission drops significantly. This notion is further supported by the evident dissociation between the stimulation driven pre-synaptic STN somatic inhibition and the post-synaptic axonal activation of its downstream targets. Thus, BG output maintains its firing rate while losing the deleterious effect of the STN. This may be a part of the mechanism leading to the beneficial effect of DBS in PD.

  8. Deficit in sustained attention following selective cholinergic lesion of the pedunculopontine tegmental nucleus in rat, as measured with both post-mortem immunocytochemistry and in vivo PET imaging with [¹⁸F]fluoroethoxybenzovesamicol.

    PubMed

    Cyr, Marilyn; Parent, Maxime J; Mechawar, Naguib; Rosa-Neto, Pedro; Soucy, Jean-Paul; Clark, Stewart D; Aghourian, Meghmik; Bedard, Marc-Andre

    2015-02-01

    Cholinergic neurons of the pedunculopontine tegmental nucleus (PPTg) are thought to be involved in cognitive functions such as sustained attention, and lesions of these cells have been documented in patients showing fluctuations of attention such as in Parkinson's disease or dementia with Lewy Body. Animal studies have been conducted to support the role of these cells in attention, but the lesions induced in these animals were not specific to the cholinergic PPTg system, and were assessed by post-mortem methods remotely performed from the in vivo behavioral assessments. Moreover, sustained attention have not been directly assessed in these studies, but rather deduced from indirect measurements. In the present study, rats were assessed on the 5-Choice Serial Reaction Time Task (5-CSRTT), and a specific measure of variability in response latency was created. Animals were observed both before and after selective lesion of the PPTg cholinergic neurons. Brain cholinergic denervation was assessed both in vivo and ex vivo, using PET imaging with [(18)F]fluoroethoxybenzovesamicol ([(18)F]FEOBV) and immunocytochemistry respectively. Results showed that the number of correct responses and variability in response latency in the 5-CSRTT were the only behavioral measures affected following the lesions. These measures were found to correlate significantly with the number of PPTg cholinergic cells, as measured with both [(18)F]FEOBV and immunocytochemistry. This suggests the primary role of the PPTg cholinergic cells in sustained attention. It also allows to reliably use the PET imaging with [(18)F]FEOBV for the purpose of assessing the relationship between behavior and cholinergic innervation in living animals. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Deep Brain Stimulation of the Subthalamic Nucleus Parameter Optimization for Vowel Acoustics and Speech Intelligibility in Parkinson's Disease

    ERIC Educational Resources Information Center

    Knowles, Thea; Adams, Scott; Abeyesekera, Anita; Mancinelli, Cynthia; Gilmore, Greydon; Jog, Mandar

    2018-01-01

    Purpose: The settings of 3 electrical stimulation parameters were adjusted in 12 speakers with Parkinson's disease (PD) with deep brain stimulation of the subthalamic nucleus (STN-DBS) to examine their effects on vowel acoustics and speech intelligibility. Method: Participants were tested under permutations of low, mid, and high STN-DBS frequency,…

  10. Stimulation of contacts in ventral but not dorsal subthalamic nucleus normalizes response switching in Parkinson's disease

    PubMed Central

    Greenhouse, Ian; Gould, Sherrie; Houser, Melissa; Aron, Adam R.

    2014-01-01

    Switching between responses is a key executive function known to rely on the frontal cortex and the basal ganglia. Here we aimed to establish with greater anatomical specificity whether such switching could be mediated via different possible frontal–basal-ganglia circuits. Accordingly, we stimulated dorsal vs. ventral contacts of electrodes in the subthalamic nucleus (STN) in Parkinson's patients during switching performance, and also studied matched controls. The patients underwent three sessions: once with bilateral dorsal contact stimulation, once with bilateral ventral contact stimulation, and once Off stimulation. Patients Off stimulation showed abnormal patterns of switching, and stimulation of the ventral contacts but not the dorsal contacts normalized the pattern of behavior relative to controls. This provides some of the first evidence in humans that stimulation of dorsal vs. ventral STN DBS contacts has differential effects on executive function. As response switching is an executive function known to rely on prefrontal cortex, these results suggest that ventral contact stimulation affected an executive/associative cortico-basal ganglia circuit. PMID:23562963

  11. Enhanced consumption of salient solutions following pedunculopontine tegmental lesions.

    PubMed

    MacLaren, D A A; Markovic, T; Daniels, D; Clark, S D

    2015-01-22

    Rats with lesions of the pedunculopontine tegmental nucleus (PPTg) reliably overconsume high concentration sucrose solution. This effect is thought to be indicative of response-perseveration or loss of behavioral control in conditions of high excitement. While these theories have anatomical and behavioral support, they have never been explicitly tested. Here, we used a contact lickometer to examine the microstructure of drinking behavior to gain insight into the behavioral changes during overconsumption. Rats received either excitotoxic (ibotenic acid) damage to all PPTg neuronal subpopulations or selective depletion of the cholinergic neuronal sub-population (diphtheria toxin-urotensin II (Dtx-UII) lesions). We offered rats a variety of pleasant, neutral and aversive tastants to assess the generalizability and specificity of the overconsumption effect. Ibotenic-lesioned rats consumed significantly more 20% sucrose than sham controls, and did so through licking significantly more times. However, the behavioral microstructure during overconsumption was unaffected by the lesion and showed no indications of response-perseveration. Furthermore, the overconsumption effect did not generalize to highly consumed saccharin. In contrast, while only consuming small amounts of quinine solution, ibotenic-lesioned rats had significantly more licks and bursts for this tastant. Selective depletion of cholinergic PPTg neurons had no effect on consumption of any tastant. We then assessed whether it is the salience of the solution which determines overconsumption by ibotenic-lesioned rats. While maintained on free-food, ibotenic-lesioned rats had normal consumption of sucrose and hypertonic saline. After mild food deprivation ibotenic PPTg-lesioned rats overconsumed 20% sucrose. Subsequently, after dietary-induced sodium deficiency, lesioned rats consumed significantly more saline than controls. These results establish that it is the salience of the solution which is the determining

  12. Surgical treatment of Parkinson’s disease: Past, present, and future

    PubMed Central

    Duker, Andrew P.; Espay, Alberto J.

    2013-01-01

    Advances in functional neurosurgery have expanded the treatment of Parkinson’s disease (PD), from early lesional procedures to targeted electrical stimulation of specific nodes in the basal ganglia circuitry. Deep brain stimulation (DBS), applied to selected patients with Parkinson’s disease (PD) and difficult-to-manage motor fluctuations, yields substantial reductions in off time and dyskinesia. Outcomes for DBS targeting the two major studied targets in PD, the subthalamic nucleus (STN) and the internal segment of the globus pallidus (GPi), appear to be broadly similar and the choice is best made based on individual patient factors and surgeon preference. Emerging concepts in DBS include examination of new targets, such as the potential efficacy of pedunculopontine nucleus (PPN) stimulation for treatment of freezing and falls, the utilization of pathologic oscillations in the beta band to construct an adaptive “closed-loop” DBS, and new technologies, including segmented electrodes to steer current toward specific neural populations. PMID:23896506

  13. Our first decade of experience in deep brain stimulation of the brainstem: elucidating the mechanism of action of stimulation of the ventrolateral pontine tegmentum.

    PubMed

    Mazzone, Paolo; Vilela Filho, Osvaldo; Viselli, Fabio; Insola, Angelo; Sposato, Stefano; Vitale, Flora; Scarnati, Eugenio

    2016-07-01

    The region of the pedunculopontine tegmental nucleus (PPTg) has been proposed as a novel target for deep brain stimulation (DBS) to treat levodopa resistant symptoms in motor disorders. Recently, the anatomical organization of the brainstem has been revised and four new distinct structures have been represented in the ventrolateral pontine tegmentum area in which the PPTg was previously identified. Given this anatomical reassessment, and considering the increasing of our experience, in this paper we revisit the value of DBS applied to that area. The reappraisal of clinical outcomes in the light of this revisitation may also help to understand the consequences of DBS applied to structures located in the ventrolateral pontine tegmentum, apart from the PPTg. The implantation of 39 leads in 32 patients suffering from Parkinson's disease (PD, 27 patients) and progressive supranuclear palsy (PSP, four patients) allowed us to reach two major conclusions. The first is that the results of the advancement of our technique in brainstem DBS matches the revision of brainstem anatomy. The second is that anatomical and functional aspects of our findings may help to explain how DBS acts when applied in the brainstem and to identify the differences when it is applied either in the brainstem or in the subthalamic nucleus. Finally, in this paper we discuss how the loss of neurons in brainstem nuclei occurring in both PD and PSP, the results of intraoperative recording of somatosensory evoked potentials, and the improvement of postural control during DBS point toward the potential role of ascending sensory pathways and/or other structures in mediating the effects of DBS applied in the ventrolateral pontine tegmentum region.

  14. Intensive Voice Treatment (LSVT[R]LOUD) for Parkinson's Disease Following Deep Brain Stimulation of the Subthalamic Nucleus

    ERIC Educational Resources Information Center

    Spielman, Jennifer; Mahler, Leslie; Halpern, Angela; Gilley, Phllip; Klepitskaya, Olga; Ramig, Lorraine

    2011-01-01

    Purpose: Intensive voice therapy (LSVT[R]LOUD) can effectively manage voice and speech symptoms associated with idiopathic Parkinson disease (PD). This small-group study evaluated voice and speech in individuals with and without deep brain stimulation of the subthalamic nucleus (STN-DBS) before and after LSVT LOUD, to determine whether outcomes…

  15. Effects of Stimulation of the Subthalamic Nucleus on Naming and Reading Nouns and Verbs in Parkinson's Disease

    ERIC Educational Resources Information Center

    Silveri, Maria Caterina; Ciccarelli, Nicoletta; Baldonero, Eleonora; Piano, Carla; Zinno, Massimiliano; Soleti, Francesco; Bentivoglio, Anna Rita; Albanese, Alberto; Daniele, Antonio

    2012-01-01

    An impairment for verbs has been described in patients with Parkinson's disease (PD), suggesting that a disruption of frontal-subcortical circuits may result in dysfunction of the neural systems involved in action-verb processing. A previous study suggested that deep brain stimulation (DBS) of the subthalamic nucleus (STN) during verb generation…

  16. Optogenetic versus electrical stimulation of dopamine terminals in the nucleus accumbens reveals local modulation of presynaptic release

    PubMed Central

    Melchior, James R.; Ferris, Mark J.; Stuber, Garret D.; Riddle, David R.; Jones, Sara R.

    2015-01-01

    The nucleus accumbens is highly heterogeneous, integrating regionally distinct afferent projections and accumbal interneurons, resulting in diverse local microenvironments. Dopamine (DA) neuron terminals similarly express a heterogeneous collection of terminal receptors that modulate DA signaling. Cyclic voltammetry is often used to probe DA terminal dynamics in brain slice preparations; however, this method traditionally requires electrical stimulation to induce DA release. Electrical stimulation excites all of the neuronal processes in the stimulation field, potentially introducing simultaneous, multi-synaptic modulation of DA terminal release. We used optogenetics to selectively stimulate DA terminals and used voltammetry to compare DA responses from electrical and optical stimulation of the same area of tissue around a recording electrode. We found that with multiple pulse stimulation trains, optically stimulated DA release increasingly exceeded that of electrical stimulation. Furthermore, electrical stimulation produced inhibition of DA release across longer duration stimulations. The GABAB antagonist, CGP 55845, increased electrically stimulated DA release significantly more than light stimulated release. The nicotinic acetylcholine receptor antagonist, dihydro-β-erythroidine hydrobromide, inhibited single pulse electrically stimulated DA release while having no effect on optically stimulated DA release. Our results demonstrate that electrical stimulation introduces local multi-synaptic modulation of DA release that is absent with optogenetically targeted stimulation. PMID:26011081

  17. Electrical stimulation of rhesus monkey nucleus reticularis gigantocellularis. I. Characteristics of evoked head movements.

    PubMed

    Quessy, Stephan; Freedman, Edward G

    2004-06-01

    The nucleus reticularis gigantocellularis (NRG) receives monosynaptic input from the superior colliculus (SC) and projects directly to neck motor neuron pools. Neurons in NRG are well situated to play a critical role in transforming SC signals into head movement commands. A previous study of movements evoked by NRG stimulation in the primate reported a variety of ipsilateral and contralateral head movements with horizontal, vertical and torsional components. In addition to head movements, it was reported that NRG stimulation could evoke movements of the pinnae, face, upper torso, and co-contraction of neck muscles. In this report, the role of the rhesus monkey NRG in head movement control was investigated using electrical stimulation of the rostral portion of the NRG. The goal was to characterize head movements evoked by NRG stimulation, describe the effects of altering stimulation parameters, and assess the relative movements of the eyes and head. Results indicate that electrical stimulation in the rostral portion of the NRG of the primate can consistently evoke ipsilateral head rotations in the horizontal plane. Head movement amplitude and peak velocity depend upon stimulation parameters (primarily frequency and duration of stimulation trains). During stimulation-induced head movements the eyes counter-rotate (presumably a result of the vestibulo-ocular reflex: VOR). At 46 stimulation sites from two subjects the average gain of this counter-rotation was -0.38 (+/-0.18). After the end of the stimulation train the head generally continued to move. During this epoch, after electrical stimulation ceased, VOR gain remained at this reduced level. In addition, VOR gain was similarly low when electrical stimulation was carried out during active fixation of a visual target. These data extend existing descriptions of head movements evoked by electrical stimulation of the NRG, and add to the understanding of the role of this structure in producing head movements.

  18. MSG-Evoked c-Fos Activity in the Nucleus of the Solitary Tract Is Dependent upon Fluid Delivery and Stimulation Parameters

    PubMed Central

    Thompson, John A.

    2016-01-01

    The marker of neuronal activation, c-Fos, can be used to visualize spatial patterns of neural activity in response to taste stimulation. Because animals will not voluntarily consume aversive tastes, these stimuli are infused directly into the oral cavity via intraoral cannulae, whereas appetitive stimuli are given in drinking bottles. Differences in these 2 methods make comparison of taste-evoked brain activity between results that utilize these methods problematic. Surprisingly, the intraoral cannulae experimental conditions that produce a similar pattern of c-Fos activity in response to taste stimulation remain unexplored. Stimulation pattern (e.g., constant/intermittent) and hydration state (e.g., water-restricted/hydrated) are the 2 primary differences between delivering tastes via bottles versus intraoral cannulae. Thus, we quantified monosodium glutamate (MSG)-evoked brain activity, as measured by c-Fos, in the nucleus of the solitary tract (nTS; primary taste nucleus) across several conditions. The number and pattern of c-Fos neurons in the nTS of animals that were water-restricted and received a constant infusion of MSG via intraoral cannula most closely mimicked animals that consumed MSG from a bottle. Therefore, in order to compare c-Fos activity between cannulae-stimulated and bottle-stimulated animals, cannulated animals should be water restricted prior to stimulation, and receive taste stimuli at a constant flow. PMID:26762887

  19. Motor behaviors in the sheep evoked by electrical stimulation of the subthalamic nucleus.

    PubMed

    Lentz, Linnea; Zhao, Yan; Kelly, Matthew T; Schindeldecker, William; Goetz, Steven; Nelson, Dwight E; Raike, Robert S

    2015-11-01

    Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is used to treat movement disorders, including advanced Parkinson's disease (PD). The pathogenesis of PD and the therapeutic mechanisms of DBS are not well understood. Large animal models are essential for investigating the mechanisms of PD and DBS. The purpose of this study was to develop a novel sheep model of STN DBS and quantify the stimulation-evoked motor behaviors. To do so, a large sample of animals was chronically-implanted with commercial DBS systems. Neuroimaging and histology revealed that the DBS leads were implanted accurately relative to the neurosurgical plan and also precisely relative to the STN. It was also possible to repeatedly conduct controlled evaluations of stimulation-evoked motor behavior in the awake-state. The evoked motor responses depended on the neuroanatomical location of the electrode contact selected for stimulation, as contacts proximal to the STN evoked movements at significantly lower voltages. Tissue stimulation modeling demonstrated that selecting any of the contacts stimulated the STN, whereas selecting the relatively distal contacts often also stimulated thalamus but only the distal-most contact stimulated internal capsule. The types of evoked motor behaviors were specific to the stimulation frequency, as low but not high frequencies consistently evoked movements resembling human tremor or dyskinesia. Electromyography confirmed that the muscle activity underlying the tremor-like movements in the sheep was consistent with human tremor. Overall, this work establishes that the sheep is a viable a large-animal platform for controlled testing of STN DBS with objective motor outcomes. Moreover, the results support the hypothesis that exaggerated low-frequency activity within individual nodes of the motor network can drive symptoms of human movement disorders, including tremor and dyskinesia. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Effects of varying subthalamic nucleus stimulation on apraxia of lid opening in Parkinson's disease.

    PubMed

    Tommasi, Giorgio; Krack, Paul; Fraix, Valérie; Pollak, Pierre

    2012-09-01

    Apraxia of lid opening (ALO) is a non-paralytic inability to open the eyes or sustain lid elevation at will. The exact pathophysiological mechanisms underlying the syndrome are still unknown. ALO has been reported in patients with Parkinson's disease (PD) after subthalamic nucleus (STN) deep brain stimulation (DBS), suggesting a possible involvement of the basal ganglia. We aimed to assess the effects of varying STN stimulation voltage on ALO in PD patients. Seven out of 14 PD patients with bilateral STN stimulation consecutively seen in our centre presented with ALO. We progressively increased voltage on each STN, using either 130 Hz (high-frequency stimulation, HFS) or 2 or 3 Hz (low-frequency stimulation, LFS). In five patients, HFS induced ALO time-locked to stimulation in 7 out of 10 STNs at a voltage higher than that used for chronic stimulation. LFS induced myoclonus in the pretarsal orbicularis oculi muscle (pOOm) with a rhythm synchronous to the frequency. In the other two patients with ALO already present at the time of the study, HFS improved ALO in 3 out of 4 STNs. ALO recurred within minutes of stimulation arrest. Our findings show that STN-DBS can have opposite effects on ALO. On the one hand, ALO is thought to be a corticobulbar side effect due to lateral current spreading from the STN, in which case it is necessary to use voltages below the ALO-inducing threshold. On the other hand, ALO may be considered a form of off-phase focal dystonia possibly improved by increasing the stimulation voltages.

  1. Dynamic risk control by human nucleus accumbens

    PubMed Central

    Lopez-Sosa, Fernando; Gonzalez-Rosa, Javier Jesus; Galarza, Ana; Avecillas, Josue; Pineda-Pardo, Jose Angel; Lopez-Ibor, Juan José; Reneses, Blanca; Barcia, Juan Antonio

    2015-01-01

    Real-world decisions about reward often involve a complex counterbalance of risk and value. Although the nucleus accumbens has been implicated in the underlying neural substrate, its criticality to human behaviour remains an open question, best addressed with interventional methodology that probes the behavioural consequences of focal neural modulation. Combining a psychometric index of risky decision-making with transient electrical modulation of the nucleus accumbens, here we reveal profound, highly dynamic alteration of the relation between probability of reward and choice during therapeutic deep brain stimulation in four patients with treatment-resistant psychiatric disease. Short-lived phasic electrical stimulation of the region of the nucleus accumbens dynamically altered risk behaviour, transiently shifting the psychometric function towards more risky decisions only for the duration of stimulation. A critical, on-line role of human nucleus accumbens in dynamic risk control is thereby established. PMID:26428667

  2. Programming for Stimulation-Induced Transient Nonmotor Psychiatric Symptoms after Bilateral Subthalamic Nucleus Deep Brain Stimulation for Parkinson's Disease

    PubMed Central

    Wu, Xi; Qiu, Yiqing; Simfukwe, Keith; Wang, Jiali; Chen, Jianchun

    2017-01-01

    Background Stimulation-induced transient nonmotor psychiatric symptoms (STPSs) are side effects following bilateral subthalamic nucleus deep brain stimulation (STN-DBS) in Parkinson's disease (PD) patients. We designed algorithms which (1) determine the electrode contacts that induce STPSs and (2) provide a programming protocol to eliminate STPS and maintain the optimal motor functions. Our objective is to test the effectiveness of these algorithms. Materials and Methods 454 PD patients who underwent programming sessions after STN-DBS implantations were retrospectively analyzed. Only STPS patients were enrolled. In these patients, the contacts inducing STPS were found and the programming protocol algorithms used. Results Eleven patients were diagnosed with STPS. Of these patients, two had four episodes of crying, and two had four episodes of mirthful laughter. In one patient, two episodes of abnormal sense of spatial orientation were observed. Hallucination episodes were observed twice in one patient, while five patients recorded eight episodes of hypomania. There were no statistical differences between the UPDRS-III under the final stimulation parameter (without STPS) and previous optimum UPDRS-III under the STPSs (p = 1.000). Conclusion The flow diagram used for determining electrode contacts that induce STPS and the programming protocol employed in the treatment of these symptoms are effective. PMID:28894620

  3. Arousal mechanisms related to posture and locomotion: 1. Descending modulation.

    PubMed

    Garcia-Rill, Edgar; Homma, Yutaka; Skinner, Robert D

    2004-01-01

    Much of the controversy surrounding the induction of locomotion following stimulation of mesopontine sites, including the pedunculopontine nucleus (PPN), appears based on procedural differences, including stimulus onset, delay preceding stepping, and frequency of stimuli. The results reviewed in this chapter address these issues and provide novel information suggesting that descending projections from the PPN may exert a frequency-dependent effect. Stimulation at approximately 60 Hz (which induces prolonged tonic firing) may exercise a "push" towards locomotion (activation of pontine interneurons) as well as a "pull" away from decreased muscle tone (inhibiting giant pontine reticulospinal cells). Higher frequencies of stimulation (> 100 Hz, which induces phasic burst-like activity) may "push" towards decreases in muscle tone, including the atonia of rapid eye movement sleep (activating giant pontine reticulospinal cells).

  4. Role of dysphagia in evaluating Parkinson patients for subthalamic nucleus stimulation: a case report.

    PubMed

    Allert, Niels; Kelm, Daniela; Spottke, Annika; Coenen, Volker A

    2011-09-01

    In the selection of Parkinson patients for deep brain stimulation (DBS) of the subthalamic nucleus (STN) a risk-benefit-analysis is performed regarding symptoms that commonly improve and symptoms that may deteriorate. Speech is among the symptoms that may deteriorate. In contrast, the differential effects of STN-DBS on swallowing are less clear. Here, we present a Parkinson patient with dysphagia from concomitant oculo-pharyngeal muscle dystrophy successfully treated by STN-DBS. The role of dysphagia in evaluating Parkinson patients for STN-DBS is discussed.

  5. MSG-Evoked c-Fos Activity in the Nucleus of the Solitary Tract Is Dependent upon Fluid Delivery and Stimulation Parameters.

    PubMed

    Stratford, Jennifer M; Thompson, John A

    2016-03-01

    The marker of neuronal activation, c-Fos, can be used to visualize spatial patterns of neural activity in response to taste stimulation. Because animals will not voluntarily consume aversive tastes, these stimuli are infused directly into the oral cavity via intraoral cannulae, whereas appetitive stimuli are given in drinking bottles. Differences in these 2 methods make comparison of taste-evoked brain activity between results that utilize these methods problematic. Surprisingly, the intraoral cannulae experimental conditions that produce a similar pattern of c-Fos activity in response to taste stimulation remain unexplored. Stimulation pattern (e.g., constant/intermittent) and hydration state (e.g., water-restricted/hydrated) are the 2 primary differences between delivering tastes via bottles versus intraoral cannulae. Thus, we quantified monosodium glutamate (MSG)-evoked brain activity, as measured by c-Fos, in the nucleus of the solitary tract (nTS; primary taste nucleus) across several conditions. The number and pattern of c-Fos neurons in the nTS of animals that were water-restricted and received a constant infusion of MSG via intraoral cannula most closely mimicked animals that consumed MSG from a bottle. Therefore, in order to compare c-Fos activity between cannulae-stimulated and bottle-stimulated animals, cannulated animals should be water restricted prior to stimulation, and receive taste stimuli at a constant flow. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  6. Conditioned Medium Derived from Notochordal Cell-Rich Nucleus Pulposus Tissue Stimulates Matrix Production by Canine Nucleus Pulposus Cells and Bone Marrow-Derived Stromal Cells

    PubMed Central

    de Vries, Stefan A.H.; Potier, Esther; van Doeselaar, Marina; Meij, Björn P.; Tryfonidou, Marianna A.

    2015-01-01

    Objectives: Conditioned medium derived from notochordal cell-rich nucleus pulposus tissue (NCCM) was previously shown to have a stimulatory effect on bone marrow stromal cells (BMSCs) and nucleus pulposus cells (NPCs) individually, in mixed species in vitro cell models. The objective of the current study was to assess the stimulatory effect of NCCM on NPCs in a homologous canine in vitro model and to investigate whether combined stimulation with NCCM and addition of BMSCs provides a synergistic stimulatory effect. Methods: BMSCs and NPCs were harvested from chondrodystrophic dogs with confirmed early intervertebral disc (IVD) degeneration. NCCM was produced from NP tissue of nonchondrodystrophic dogs with healthy IVDs. BMSCs or NPCs alone (3×106 cells/mL) and NPCs+BMSCs (6×106 cells/mL; mixed 1:1) were cultured for 4 weeks in 1.2% alginate beads under base medium (BM), NCCM, or with addition of 10 ng/mL transforming growth factor-β1 (TGF-β1) as a positive control. Beads were assessed for glycosaminoglycan (GAG) and DNA contents by biochemical assays, GAG deposition by Alcian blue staining, and gene expression (aggrecan, versican, collagen 1 and 2, SOX9, A disintegrin and metalloproteinase with thrombospondin motifs 5 (ADAMTS5), and matrix metalloproteinase 13 [MMP13]) with real-time quantitative RT-PCR. Results: NCCM increased NPC proliferation, proteoglycan production, and expression of genes associated with a healthy NP-like phenotype. BMSCs also showed increased proteoglycan production under NCCM, but these effects were not observed at the gene level. Combined stimulation of NPCs with NCCM and coculturing with BMSCs did not result in increased proteoglycan content compared to stimulation with NCCM alone. Discussion: NCCM stimulates matrix production by both NPCs and BMSCs and directs NPCs toward a healthier phenotype. NCCM is therefore promising for IVD regeneration and identification of the bioactive components will be helpful to further develop this

  7. ExPPNing how acetylcholine improves gait in Parkinson's disease: An Editorial Highlight for 'Deletion of the Vesicular Acetylcholine Transporter from Pedunculopontine/laterodorsal tegmental neurons modifies gait'.

    PubMed

    Falkenburger, Björn

    2017-03-01

    Read the highlighted article 'Deletion of the Vesicular Acetylcholine Transporter from Pedunculopontine/laterodorsal tegmental neurons modifies gait' on page 787. © 2017 International Society for Neurochemistry.

  8. Segregated cholinergic transmission modulates dopamine neurons integrated in distinct functional circuits.

    PubMed

    Dautan, Daniel; Souza, Albert S; Huerta-Ocampo, Icnelia; Valencia, Miguel; Assous, Maxime; Witten, Ilana B; Deisseroth, Karl; Tepper, James M; Bolam, J Paul; Gerdjikov, Todor V; Mena-Segovia, Juan

    2016-08-01

    Dopamine neurons in the ventral tegmental area (VTA) receive cholinergic innervation from brainstem structures that are associated with either movement or reward. Whereas cholinergic neurons of the pedunculopontine nucleus (PPN) carry an associative/motor signal, those of the laterodorsal tegmental nucleus (LDT) convey limbic information. We used optogenetics and in vivo juxtacellular recording and labeling to examine the influence of brainstem cholinergic innervation of distinct neuronal subpopulations in the VTA. We found that LDT cholinergic axons selectively enhanced the bursting activity of mesolimbic dopamine neurons that were excited by aversive stimulation. In contrast, PPN cholinergic axons activated and changed the discharge properties of VTA neurons that were integrated in distinct functional circuits and were inhibited by aversive stimulation. Although both structures conveyed a reinforcing signal, they had opposite roles in locomotion. Our results demonstrate that two modes of cholinergic transmission operate in the VTA and segregate the neurons involved in different reward circuits.

  9. Neuronal Responses in the Globus Pallidus during Subthalamic Nucleus Electrical Stimulation in Normal and Parkinson's Disease Model Rats

    PubMed Central

    Ryu, Sang Baek; Bae, Eun Kyung; Kim, Jinhyung; Hwang, Yong Sup; Im, Changkyun; Chang, Jin Woo; Shin, Hyung-Cheul

    2013-01-01

    Deep brain stimulation (DBS) of the subthalamic nucleus (STN) has been widely used as a treatment for the movement disturbances caused by Parkinson's disease (PD). Despite successful application of DBS, its mechanism of therapeutic effect is not clearly understood. Because PD results from the degeneration of dopamine neurons that affect the basal ganglia (BG) network, investigation of neuronal responses of BG neurons during STN DBS can provide informative insights for the understanding of the mechanism of therapeutic effect. However, it is difficult to observe neuronal activity during DBS because of large stimulation artifacts. Here, we report the observation of neuronal activities of the globus pallidus (GP) in normal and PD model rats during electrical stimulation of the STN. A custom artifact removal technique was devised to enable monitoring of neural activity during stimulation. We investigated how GP neurons responded to STN stimulation at various stimulation frequencies (10, 50, 90 and 130 Hz). It was observed that activities of GP neurons were modulated by stimulation frequency of the STN and significantly inhibited by high frequency stimulation above 50 Hz. These findings suggest that GP neuronal activity is effectively modulated by STN stimulation and strongly dependent on the frequency of stimulation. PMID:23946689

  10. Pitch Variability in Patients with Parkinson's Disease: Effects of Deep Brain Stimulation of Caudal Zona Incerta and Subthalamic Nucleus

    ERIC Educational Resources Information Center

    Karlsson, Fredrik; Olofsson, Katarina; Blomstedt, Patric; Linder, Jan; van Doorn, Jan

    2013-01-01

    Purpose: The purpose of the present study was to examine the effect of deep brain stimulation (DBS) of the subthalamic nucleus (STN) and the caudal zona incerta (cZi) pitch characteristics of connected speech in patients with Parkinson's disease (PD). Method: The authors evaluated 16 patients preoperatively and 12 months after DBS surgery. Eight…

  11. Subthalamic nucleus deep brain stimulation improves somatosensory function in Parkinson's disease.

    PubMed

    Aman, Joshua E; Abosch, Aviva; Bebler, Maggie; Lu, Chia-Hao; Konczak, Jürgen

    2014-02-01

    An established treatment for the motor symptoms of Parkinson's disease (PD) is deep brain stimulation (DBS) of the subthalamic nucleus (STN). Mounting evidence suggests that PD is also associated with somatosensory deficits, yet the effect of STN-DBS on somatosensory processing is largely unknown. This study investigated whether STN-DBS affects somatosensory processing, specifically the processing of tactile and proprioceptive cues, by systematically examining the accuracy of haptic perception of object size. (Haptic perception refers to one's ability to extract object features such as shape and size by active touch.) Without vision, 13 PD patients with implanted STN-DBS and 13 healthy controls haptically explored the heights of 2 successively presented 3-dimensional (3D) blocks using a precision grip. Participants verbally indicated which block was taller and then used their nonprobing hand to motorically match the perceived size of the comparison block. Patients were tested during ON and OFF stimulation, following a 12-hour medication washout period. First, when compared to controls, the PD group's haptic discrimination threshold during OFF stimulation was elevated by 192% and mean hand aperture error was increased by 105%. Second, DBS lowered the haptic discrimination threshold by 26% and aperture error decreased by 20%. Third, during DBS ON, probing with the motorically more affected hand decreased haptic precision compared to probing with the less affected hand. This study offers the first evidence that STN-DBS improves haptic precision, further indicating that somatosensory function is improved by STN-DBS. We conclude that DBS-related improvements are not explained by improvements in motor function alone, but rather by enhanced somatosensory processing. © 2013 Movement Disorder Society.

  12. Increases in food intake or food-seeking behavior induced by GABAergic, opioid, or dopaminergic stimulation of the nucleus accumbens: is it hunger?

    PubMed

    Hanlon, Erin C; Baldo, Brian A; Sadeghian, Ken; Kelley, Ann E

    2004-03-01

    Previous work has shown that stimulation of GABAergic, opioid, or dopaminergic systems within the nucleus accumbens modulates food intake and food-seeking behavior. However, it is not known whether such stimulation mimics a motivational state of food deprivation that commonly enables animals to learn a new operant response to obtain food. In order to address this question, acquisition of lever pressing for food in hungry animals was compared with acquisition in non-food-deprived rats subjected to various nucleus accumbens drug treatments. All animals were given the opportunity to learn an instrumental response (a lever press) to obtain a food pellet. Prior to training, ad lib-fed rats were infused with the gamma-aminobutyric acid (GABA)A agonist muscimol (100 ng/0.5 microl per side) or the mu-opioid receptor agonist D-Ala2, N-me-Phe4, Gly-ol5-enkephalin (DAMGO, 0.25 microg/0.5 microl per side), or saline into the nucleus accumbens shell (AcbSh). The indirect dopamine agonist amphetamine (10 microg/0.5 microl per side) was infused into the AcbSh or nucleus accumbens core (AcbC) of ad lib-fed rats. An additional group was food deprived and infused with saline in the AcbSh. Chow and sugar pellet intake responses after drug treatments were also evaluated in free-feeding tests. Muscimol, DAMGO, or amphetamine did not facilitate acquisition of lever pressing for food, despite clearly increasing food intake in free-feeding tests. In contrast, food-deprived animals rapidly learned the task. These findings suggest that pharmacological stimulation of any of these neurochemical systems in isolation is insufficient to enable acquisition of a food-reinforced operant task. Thus, these selective processes, while likely involved in control of food intake and food-seeking behavior, appear unable to recapitulate the conditions necessary to mimic the state of negative energy balance.

  13. Stimulation of D2 receptors in the prefrontal cortex reduces PCP-induced hyperactivity, acetylcholine release and dopamine metabolism in the nucleus accumbens.

    PubMed

    Del Arco, A; Mora, F; Mohammed, A H; Fuxe, K

    2007-02-01

    The aim of the present study was to investigate the effects of stimulation of D2 receptors in the prefrontal cortex (PFC) on spontaneous motor activity and the hyperactivity induced by the psychomimetic phencyclidine (PCP). In addition, the effects of prefrontal D2 stimulation under PCP treatment on dialysate concentrations of acetylcholine, choline, dopamine, DOPAC and HVA in the nucleus accumbens were also investigated. Sprague-Dawley male rats were implanted with guide cannulae to perform bilateral injections into the medial PFC of the D2 agonist quinpirole (1.5 and 5 microg/side). Horizontal and vertical spontaneous motor activity and the motor activity induced by systemic injections of the PCP (5 mg/kg i.p.) were monitored in the open field. PFC injections of quinpirole (1.5 and 5 microg/side) significantly decreased horizontal and vertical spontaneous motor activity in a dose-related manner. These effects were blocked by the D2 antagonist raclopride (5 microg/side). Microinjections of quinpirole (1.5 and 5 microg/side) into the PFC also significantly attenuated the hyperactivity produced by PCP (5 mg/kg i.p.). PCP also increased dialysate concentrations of acetylcholine, and dopamine metabolites in the nucleus accumbens. These increases were also reduced by injections of quinpirole (5 microg/side) into the PFC. These results suggest that the stimulation of prefrontal D2 receptors plays an inhibitory role in regulating spontaneous and PCP-induced motor activity and also in the neurochemical changes produced by PCP in the nucleus accumbens.

  14. Subthalamic nucleus stimulation does not influence basal glucose metabolism or insulin sensitivity in patients with Parkinson's disease.

    PubMed

    Lammers, Nicolette M; Sondermeijer, Brigitte M; Twickler, Th B Marcel; de Bie, Rob M; Ackermans, Mariëtte T; Fliers, Eric; Schuurman, P Richard; La Fleur, Susanne E; Serlie, Mireille J

    2014-01-01

    Animal studies have shown that central dopamine signaling influences glucose metabolism. As a first step to show this association in an experimental setting in humans, we studied whether deep brain stimulation (DBS) of the subthalamic nucleus (STN), which modulates the basal ganglia circuitry, alters basal endogenous glucose production (EGP) or insulin sensitivity in patients with Parkinson's disease (PD). We studied 8 patients with PD treated with DBS STN, in the basal state and during a hyperinsulinemic euglycemic clamp using a stable glucose isotope, in the stimulated and non-stimulated condition. We measured EGP, hepatic insulin sensitivity, peripheral insulin sensitivity (Rd), resting energy expenditure (REE), glucoregulatory hormones, and Parkinson symptoms, using the Unified Parkinson's Disease Rating Scale (UPDRS). Basal plasma glucose and EGP did not differ between the stimulated and non-stimulated condition. Hepatic insulin sensitivity was similar in both conditions and there were no significant differences in Rd and plasma glucoregulatory hormones between DBS on and DBS off. UPDRS was significantly higher in the non-stimulated condition. DBS of the STN in patients with PD does not influence basal EGP or insulin sensitivity. These results suggest that acute modulation of the motor basal ganglia circuitry does not affect glucose metabolism in humans.

  15. Vestibular signals in the parasolitary nucleus.

    PubMed

    Barmack, N H; Yakhnitsa, V

    2000-06-01

    Vestibular primary afferents project to secondary vestibular neurons located in the vestibular complex. Vestibular primary afferents also project to the uvula-nodulus of the cerebellum where they terminate on granule cells. In this report we describe the physiological properties of neurons in a "new" vestibular nucleus, the parasolitary nucleus (Psol). This nucleus consists of 2,300 GABAergic neurons that project onto the ipsilateral inferior olive (beta-nucleus and dorsomedial cell column) as well as the nucleus reticularis gigantocellularis. These olivary neurons are the exclusive source of vestibularly modulated climbing fiber inputs to the cerebellum. We recorded the activity of Psol neurons during natural vestibular stimulation in anesthetized rabbits. The rabbits were placed in a three-axis rate table at the center of a large sphere, permitting vestibular and optokinetic stimulation. We recorded from 74 neurons in the Psol and from 23 neurons in the regions bordering Psol. The activity of 72/74 Psol neurons and 4/23 non-Psol neurons was modulated by vestibular stimulation in either the pitch or roll planes but not the horizontal plane. Psol neurons responded in phase with ipsilateral side-down head position or velocity during sinusoidal stimulation. Approximately 80% of the recorded Psol neurons responded to static roll-tilt. The optimal response planes of evoked vestibular responses were inferred from measurement of null planes. Optimal response planes usually were aligned with the anatomical orientation of one of the two ipsilateral vertical semicircular canals. The frequency dependence of null plane measurements indicated a convergence of vestibular information from otoliths and semicircular canals. None of the recorded neurons evinced optokinetic sensitivity. These results are consistent with the view that Psol neurons provide the vestibular signals to the inferior olive that eventually reached the cerebellum in the form of modulated climbing fiber

  16. Responses to vertical vestibular stimulation of neurons in the nucleus reticularis gigantocellularis in rabbits.

    PubMed

    Fagerson, M H; Barmack, N H

    1995-06-01

    1. Because the nucleus reticularis gigantocellularis (NRGc) receives a substantial descending projection from the caudal vestibular nuclei, we used extracellular single-unit recording combined with natural vestibular stimulation to examine the possible peripheral origins of the vestibularly modulated activity of caudal NRGc neurons located within 500 microns of the midline. Chloralose-urethan anesthetized rabbits were stimulated with an exponential "step" and/or static head-tilt stimulus, as well as sinusoidal rotation about the longitudinal or interaural axes providing various combinations of roll or pitch, respectively. Recording sites were reconstructed from electrolytic lesions confirmed histologically. 2. More than 85% of the 151 neurons, in the medial aspect of the caudal NRGc, responded to vertical vestibular stimulation. Ninety-six percent of these responded to rotation onto the contralateral side (beta responses). Only a few also responded to horizontal stimulation. Seventy-eight percent of the neurons that responded to vestibular stimulation responded during static roll-tilt. One-half of these neurons also responded transiently to the change in head position during exponential "step" stimulation, suggesting input mediated by otolith and semicircular canal receptors or tonic-phasic otolith neurons. 3. Seventy-five percent of the responsive neurons had a "null plane." The planes of stimulation resulting in maximal responses, for cells that responded to static stimulation, were distributed throughout 150 degrees in both roll and pitch quadrants. Five of these cells responded only transiently during exponential "step" stimulation and responded maximally when stimulated in the plane of one of the vertical semicircular canals. 4. The phase of the response of the 25% of medial NRGc neurons that lacked "null planes" gradually shifted approximately 180 degrees during sinusoidal vestibular stimulation as the plane of stimulation was shifted about the vertical axis

  17. Effects of subthalamic nucleus stimulation on motor cortex plasticity in Parkinson disease

    PubMed Central

    Kim, Sang Jin; Udupa, Kaviraja; Ni, Zhen; Moro, Elena; Gunraj, Carolyn; Mazzella, Filomena; Lozano, Andres M.; Hodaie, Mojgan; Lang, Anthony E.

    2015-01-01

    Objective: We hypothesized that subthalamic nucleus (STN) deep brain stimulation (DBS) will improve long-term potentiation (LTP)-like plasticity in motor cortex in Parkinson disease (PD). Methods: We studied 8 patients with PD treated with STN-DBS and 9 age-matched healthy controls. Patients with PD were studied in 4 sessions in medication (Med) OFF/stimulator (Stim) OFF, Med-OFF/Stim-ON, Med-ON/Stim-OFF, and Med-ON/Stim-ON states in random order. Motor evoked potential amplitude and cortical silent period duration were measured at baseline before paired associated stimulation (PAS) and at 3 different time intervals (T0, T30, T60) up to 60 minutes after PAS in the abductor pollicis brevis and abductor digiti minimi muscles. Results: Motor evoked potential size significantly increased after PAS in controls (+67.7% of baseline at T30) and in patients in the Med-ON/Stim-ON condition (+55.8% of baseline at T30), but not in patients in the Med-OFF/Stim-OFF (−0.4% of baseline at T30), Med-OFF/Stim-ON (+10.3% of baseline at T30), and Med-ON/Stim-OFF conditions (+17.3% of baseline at T30). Cortical silent period duration increased after PAS in controls but not in patients in all test conditions. Conclusions: Our findings suggest that STN-DBS together with dopaminergic medications restore LTP-like plasticity in motor cortex in PD. Restoration of cortical plasticity may be one of the mechanisms of how STN-DBS produces clinical benefit. PMID:26156511

  18. Deep brain stimulation of anterior nucleus thalami disrupts sleep in epilepsy patients.

    PubMed

    Voges, Berthold R; Schmitt, Friedhelm C; Hamel, Wolfgang; House, Patrick M; Kluge, Christian; Moll, Christian K E; Stodieck, Stefan R

    2015-08-01

    In view of the regulatory function of the thalamus in the sleep-wake cycle, the impact of deep brain stimulation (DBS) of the anterior nucleus thalami (ANT) on sleep was assessed in a small consecutive cohort of epilepsy patients with standardized polysomnography (PSG). In nine patients treated with ANT-DBS (voltage 5 V, frequency 145 Hz, cyclic mode), the number of arousals during stimulation and nonstimulation periods, neuropsychiatric symptoms (npS), and seizure frequency were determined. Electroclinical arousals were triggered in 14.0 to 67.0% (mean 42.4 ± SD 16.8%) of all deep brain stimuli. Six patients reported npS. Nocturnal DBS voltages were reduced in eight patients (one patient without npS refused) and PSGs were repeated. Electroclinical arousals occurred between 1.4 and 6.7 (mean 3.3 ± 1.7) times more frequently during stimulation periods compared to nonstimulation periods; the number of arousals positively correlated with the level of DBS voltage (range 1 V to 5 V) (Spearman's rank coefficient 0.53121; p < 0.05). No patient experienced seizure deterioration and four patients reported remission of npS. This case-cohort study provides evidence that ANT-DBS interrupts sleep in a voltage-dependent manner, thus putatively resulting in an increase of npS. Reduction of nocturnal DBS voltage seems to lead to improvement of npS without hampering efficacy of ANT-DBS. Wiley Periodicals, Inc. © 2015 International League Against Epilepsy.

  19. Targeting of the Subthalamic Nucleus for Deep Brain Stimulation: A Survey Among Parkinson Disease Specialists.

    PubMed

    Hamel, Wolfgang; Köppen, Johannes A; Alesch, François; Antonini, Angelo; Barcia, Juan A; Bergman, Hagai; Chabardes, Stephan; Contarino, Maria Fiorella; Cornu, Philippe; Demmel, Walter; Deuschl, Günther; Fasano, Alfonso; Kühn, Andrea A; Limousin, Patricia; McIntyre, Cameron C; Mehdorn, H Maximilian; Pilleri, Manuela; Pollak, Pierre; Rodríguez-Oroz, Maria C; Rumià, Jordi; Samuel, Michael; Timmermann, Lars; Valldeoriola, Francesc; Vesper, Jan; Visser-Vandewalle, Veerle; Volkmann, Jens; Lozano, Andres M

    2017-03-01

    Deep brain stimulation within or adjacent to the subthalamic nucleus (STN) represents the most common stereotactic procedure performed for Parkinson disease. Better STN imaging is often regarded as a requirement for improving stereotactic targeting. However, it is unclear whether there is consensus about the optimal target. To obtain an expert opinion on the site regarded optimal for "STN stimulation," movement disorder specialists were asked to indicate their preferred position for an active contact on hard copies of the Schaltenbrand and Wahren atlas depicting the STN in all 3 planes. This represented an idealized setting, and it mimicked optimal imaging for direct target definition in a perfectly delineated STN. The suggested targets were heterogeneous, although some clustering was observed in the dorsolateral STN and subthalamic area. In particular, in the anteroposterior direction, the intended targets differed to a great extent. Most of the indicated targets are thought to also result in concomitant stimulation of structures adjacent to the STN, including the zona incerta, fields of Forel, and internal capsule. This survey illustrates that most sites regarded as optimal for STN stimulation are close to each other, but there appears to be no uniform perception of the optimal anatomic target, possibly influencing surgical results. The anatomic sweet zone for STN stimulation needs further specification, as this information is likely to make magnetic resonance imaging-based target definition less variable when applied to individual patients. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Deep brain stimulation of the subthalamic nucleus improves pain in Parkinson's disease.

    PubMed

    Pellaprat, Jean; Ory-Magne, Fabienne; Canivet, Cindy; Simonetta-Moreau, Marion; Lotterie, Jean-Albert; Radji, Fatai; Arbus, Christophe; Gerdelat, Angélique; Chaynes, Patrick; Brefel-Courbon, Christine

    2014-06-01

    In Parkinson's disease (PD), chronic pain is a common symptom which markedly affects the quality of life. Some physiological arguments proposed that Deep Brain Stimulation of the Subthalamic Nucleus (STN-DBS) could improve pain in PD. We investigated in 58 PD patients the effect of STN-DBS on pain using the short McGill Pain Questionnaire and other pain parameters such as the Bodily discomfort subscore of the Parkinson's disease Questionnaire 39 and the Unified Parkinson's Disease Rating Scale section II (UPDRS II) item 17. All pain scores were significantly improved 12 months after STN-DBS. This improvement was not correlated with motor improvement, depression scores or L-Dopa reduction. STN-DBS induced a substantial beneficial effect on pain in PD, independently of its motor effects and mood status of patients. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Deep brain stimulation for Parkinson's disease: defining the optimal location within the subthalamic nucleus.

    PubMed

    Bot, Maarten; Schuurman, P Richard; Odekerken, Vincent J J; Verhagen, Rens; Contarino, Fiorella Maria; De Bie, Rob M A; van den Munckhof, Pepijn

    2018-05-01

    Individual motor improvement after deep brain stimulation (DBS) of the subthalamic nucleus (STN) for Parkinson's disease (PD) varies considerably. Stereotactic targeting of the dorsolateral sensorimotor part of the STN is considered paramount for maximising effectiveness, but studies employing the midcommissural point (MCP) as anatomical reference failed to show correlation between DBS location and motor improvement. The medial border of the STN as reference may provide better insight in the relationship between DBS location and clinical outcome. Motor improvement after 12 months of 65 STN DBS electrodes was categorised into non-responding, responding and optimally responding body-sides. Stereotactic coordinates of optimal electrode contacts relative to both medial STN border and MCP served to define theoretic DBS 'hotspots'. Using the medial STN border as reference, significant negative correlation (Pearson's correlation -0.52, P<0.01) was found between the Euclidean distance from the centre of stimulation to this DBS hotspot and motor improvement. This hotspot was located at 2.8 mm lateral, 1.7 mm anterior and 2.5 mm superior relative to the medial STN border. Using MCP as reference, no correlation was found. The medial STN border proved superior compared with MCP as anatomical reference for correlation of DBS location and motor improvement, and enabled defining an optimal DBS location within the nucleus. We therefore propose the medial STN border as a better individual reference point than the currently used MCP on preoperative stereotactic imaging, in order to obtain optimal and thus less variable motor improvement for individual patients with PD following STN DBS. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  2. Visual stimulation synchronizes or desynchronizes the activity of neuron pairs between the caudate nucleus and the posterior thalamus.

    PubMed

    Rokszin, Alice; Gombköto, Péter; Berényi, Antal; Márkus, Zita; Braunitzer, Gábor; Benedek, György; Nagy, Attila

    2011-10-18

    Recent morphological and physiological studies have suggested a strong relationship between the suprageniculate nucleus (Sg) of the posterior thalamus and the input structure of the basal ganglia, the caudate nucleus (CN) of the feline brain. Accordingly, to clarify if there is a real functional relationship between Sg and CN during visual information processing, we investigated the temporal relations of simultaneously recorded neuronal spike trains of these two structures, looking for any significant cross-correlation between the spiking of the simultaneously recorded neurons. For the purposes of statistical analysis, we used the shuffle and jittering resampling methods. Of the recorded 288 Sg-CN neuron pairs, 26 (9.2%) showed significantly correlated spontaneous activity. Nineteen pairs (6.7%) showed correlated activity during stationary visual stimulation, while 21 (7.4%) pairs during stimulus movement. There was no overlap between the neuron pairs that showed cross-correlated spontaneous activity and the pairs that synchronized their activity during visual stimulation. Thus visual stimulation seems to have been able to synchronize, and also, by other neuron pairs, desynchronize the activity of CN and Sg. In about half of the cases, the activation of Sg preceded the activation of CN by a few milliseconds, while in the other half, CN was activated earlier. Our results provide the first piece of evidence for the existence of a functional cooperation between Sg and CN. We argue that either a monosynaptic bidirectional direct connection should exist between these structures, or a common input comprising of parallel pathways synchronizing them. Copyright © 2011 Elsevier B.V. All rights reserved.

  3. Technical Case Report of Deep Brain Stimulation: Is it Possible Single Electrode Reach to Both of Subthalamic Nucleus and Ventral Intermediate Nucleus in One Stage?

    PubMed

    Kaptan, Hülagu; Çakmur, Raif

    2018-04-15

    The primary target of this operation is Ventral Intermediate Nucleus (VIM); however VIM - Subthalamic Nucleus (STN) were tried to be reached with one electrode, adjusting the angle well, the coronal section; medial of VIM can partially reach the STN. Using the properties of the electrode; we believe we could act on a wide area. An analysis was performed on one patient who underwent VIM Deep Brain Stimulation (DBS) in 3 periods (pre - peri - post-operation). A 53 - year - old woman diagnosed with Parkinson's disease 8 years earlier including symptoms of severe tremor on the right than left underwent bilateral DBS VIM. Obtaining a satisfactory improvement of tremor, the patient did well, and postoperative complications were not observed. The patient was discharged from hospital on postoperative thirty day. It is certain that more research and experience are needed. However, we believe that the two targets can reach the same point and the second operations for another target can be avoided.We believe that this initiative is advantageous and promising regarding patient and cost.

  4. Does subthalamic nucleus deep brain stimulation really improve quality of life in Parkinson's disease?

    PubMed

    Gronchi-Perrin, Aline; Viollier, Sarah; Ghika, Joseph; Combremont, Pierre; Villemure, Jean-Guy; Bogousslavsky, Julien; Burkhard, Pierre R; Vingerhoets, François

    2006-09-01

    We investigated the impact of subthalamic nucleus (STN) deep brain stimulation (DBS) on quality of life (QOL) in patients with advanced Parkinson's disease, as self-assessed before and after surgery by completing the Parkinson's Disease Questionnaire (PDQ39). In addition to this prospective evaluation, we asked patients postoperatively to evaluate their preoperative QOL. In the prospective assessment, results showed that patients perceived a general improvement of QOL after the STN DBS. However, when evaluated retrospectively, they tended to overestimate their preoperative functioning, therefore obscuring the improvement found prospectively. This observation highlights the impact of the method used on obtained results when assessing the effects of STN DBS. (c) 2006 Movement Disorder Society.

  5. Camptocormia and deep brain stimulation: The interesting overlapping etiologies and the therapeutic role of subthalamic nucleus-deep brain stimulation in Parkinson disease with camptocormia.

    PubMed

    Ekmekci, Hakan; Kaptan, Hulagu

    2016-01-01

    Camptocormia is known as "bent spine syndrome" and defined as a forward hyperflexion. The most common etiologic factor is related with the movement disorders, mainly in Parkinson's disease (PD). We present the case of a 51-year-old woman who has been followed with PD for the last 10 years, and also under the therapy for PD. An unappreciated correlation low back pain with camptocormia developed. She underwent deep brain stimulation (DBS) in the subthalamic nucleus bilaterally and improved her bending posture. The relationship between the DBS and camptocormia is discussed in this unique condition.

  6. Subthalamic nucleus stimulation impairs emotional conflict adaptation in Parkinson's disease.

    PubMed

    Irmen, Friederike; Huebl, Julius; Schroll, Henning; Brücke, Christof; Schneider, Gerd-Helge; Hamker, Fred H; Kühn, Andrea A

    2017-10-01

    The subthalamic nucleus (STN) occupies a strategic position in the motor network, slowing down responses in situations with conflicting perceptual input. Recent evidence suggests a role of the STN in emotion processing through strong connections with emotion recognition structures. As deep brain stimulation (DBS) of the STN in patients with Parkinson's disease (PD) inhibits monitoring of perceptual and value-based conflict, STN DBS may also interfere with emotional conflict processing. To assess a possible interference of STN DBS with emotional conflict processing, we used an emotional Stroop paradigm. Subjects categorized face stimuli according to their emotional expression while ignoring emotionally congruent or incongruent superimposed word labels. Eleven PD patients ON and OFF STN DBS and eleven age-matched healthy subjects conducted the task. We found conflict-induced response slowing in healthy controls and PD patients OFF DBS, but not ON DBS, suggesting STN DBS to decrease adaptation to within-trial conflict. OFF DBS, patients showed more conflict-induced slowing for negative conflict stimuli, which was diminished by STN DBS. Computational modelling of STN influence on conflict adaptation disclosed DBS to interfere via increased baseline activity. © The Author (2017). Published by Oxford University Press.

  7. Constant Current versus Constant Voltage Subthalamic Nucleus Deep Brain Stimulation in Parkinson's Disease.

    PubMed

    Ramirez de Noriega, Fernando; Eitan, Renana; Marmor, Odeya; Lavi, Adi; Linetzky, Eduard; Bergman, Hagai; Israel, Zvi

    2015-02-18

    Background: Subthalamic nucleus (STN) deep brain stimulation (DBS) is an established therapy for advanced Parkinson's disease (PD). Motor efficacy and safety have been established for constant voltage (CV) devices and more recently for constant current (CC) devices. CC devices adjust output voltage to provide CC stimulation irrespective of impedance fluctuation, while the current applied by CV stimulation depends on the impedance that may change over time. No study has directly compared the clinical effects of these two stimulation modalities. Objective: To compare the safety and clinical impact of CC STN DBS to CV STN DBS in patients with advanced PD 2 years after surgery. Methods: Patients were eligible for inclusion if they had undergone STN DBS surgery for idiopathic PD, had been implanted with a Medtronic Activa PC and if their stimulation program and medication had been stable for at least 1 year. This single-center trial was designed as a double-blind, randomized, prospective study with crossover after 2 weeks. Motor equivalence of the 2 modalities was confirmed utilizing part III of the Unified Parkinson's Disease Rating Scale (UPDRS). PD diaries and multiple subjective and objective evaluations of quality of life, depression, cognition and emotional processing were evaluated on both CV and on CC stimulation. Analysis using the paired t test with Bonferroni correction for multiple comparisons was performed to identify any significant difference between the stimulation modalities. Results: 8 patients were recruited (6 men, 2 women); 1 patient did not complete the study. The average age at surgery was 56.7 years (range 47-63). Disease duration at the time of surgery was 7.5 years (range 3-12). Patients were recruited 23.8 months (range 22.5-24) after surgery. At the postoperative study baseline, this patient group showed an average motor improvement of 69% (range 51-97) as measured by the change in UPDRS part III with stimulation alone. Levodopa equivalent

  8. Beta-Galactosidase Staining in the Nucleus of the Solitary Tract of Fos-Tau-LacZ Mice Is Unaffected by Monosodium Glutamate Taste Stimulation

    PubMed Central

    Stratford, Jennifer M.; Thompson, John A.

    2014-01-01

    Fos-Tau-LacZ (FTL) transgenic mice are used to visualize the anatomical connectivity of neurons that express c-Fos, an immediate early gene, in response to activation. In contrast to typical c-Fos protein expression, which is localized to the nucleus of stimulated neurons, activation of the c-Fos gene results in beta galactosidase (β-gal) expression throughout the entire cytoplasm of activated cells in FTL mice; thereby making it possible to discern the morphology of c-Fos expressing cells. This can be an especially important tool in brain areas in which function may be related to cell morphology, such as the primary taste/viscerosensory brainstem nucleus of the solitary tract (nTS). Thus, to further characterize FTL activity in the brain, the current study quantified both β-gal enzymatic activity as well as c-Fos protein expression in the nTS under a variety of experimental conditions (no stimulation, no stimulation with prior overnight food and water restriction, monosodium glutamate taste stimulation, and monosodium glutamate taste stimulation with perfusion 5 h post stimulation). Contrary to previous research, we found that β-gal activity (both labeled cell bodies and overall number of labeled pixels) was unchanged across all experimental conditions. However, traditional c-Fos protein activity (both cell bodies and number of activated pixels) varied significantly across experimental conditions, with the greatest amount of c-Fos protein label found in the group that received monosodium glutamate taste stimulation. Interestingly, although many c-Fos positive cells were also β-gal positive in the taste stimulated group, some c-Fos protein labeled cells were not co-labeled with β-gal. Together, these data suggest that β-gal staining within the nTS reflects a stable population of β-gal- positive neurons whose pattern of expression is unaffected by experimental condition. PMID:25192442

  9. Brain-derived neurotrophic factor in the nucleus tractus solitarii modulates glucose homeostasis after carotid chemoreceptor stimulation in rats.

    PubMed

    Montero, Sergio; Cuéllar, Ricardo; Lemus, Mónica; Avalos, Reyes; Ramírez, Gladys; de Álvarez-Buylla, Elena Roces

    2012-01-01

    Neuronal systems, which regulate energy intake, energy expenditure and endogenous glucose production, sense and respond to input from hormonal related signals that convey information from body energy availability. Carotid chemoreceptors (CChr) function as sensors for circulating glucose levels and contribute to glycemic counterregulatory responses. Brain-derived neurotrophic factor (BDNF) that plays an important role in the endocrine system to regulate glucose metabolism could play a role in hyperglycemic glucose reflex with brain glucose retention (BGR) evoked by anoxic CChr stimulation. Infusing BDNF into the nucleus tractus solitarii (NTS) before CChr stimulation, showed that this neurotrophin increased arterial glucose and BGR. In contrast, BDNF receptor (TrkB) antagonist (K252a) infusions in NTS resulted in a decrease in both glucose variables.

  10. [The relationships among raphe magnus nucleus, locus coeruleus and dorsal motor nucleus of vagus in the descending regulation of gastric motility].

    PubMed

    Qiao, Hui; An, Shu-Cheng; Xu, Chang

    2011-02-01

    To explore the interrelationship among dorsal motor nucleus of the vagus (DMV), locus coeruleus (LC) and raphe magnus nucleus (NRM) in the mechanism of the descending regulation on gastric motility, which may constitute a parasympathetic local circuit, work as a neural center of gastric modulation in brainstem. Using nucleus location, electric stimulation and lesion, together with microinjection, and recording the inter-gastric pressure. (1) LC stimulation could inhibit the gastric motility significantly (P < 0.01), DMV lesion weaken this effect, while blocking the a receptor on DMV could reverse the effect. (2) NRM stimulation reduced the amplitude of gastric constriction (P < 0.01), DMV lesion could abolish the effect, but blocking the 5-HT2A receptor on DMV depressed the gastric motility heavily (P < 0.01) like NRM stimulation. While LC lesion could abolish the effect of NRM stimulation, and microinjection of ritanserin into LC could likewise abolish it. (1) LC inhibit the gastric motility via a receptor in DMV, and meanwhile may excite it through 5-HT2A receptor in DMV, these two ways work together to keeping the gastric motility amplitude normally. (2) NRM inhibit the gastric motility via 5-HT2A receptor in LC.

  11. Determination of subthalamic nucleus location by quantitative analysis of despiked background neural activity from microelectrode recordings obtained during deep brain stimulation surgery.

    PubMed

    Danish, Shabbar F; Baltuch, Gordon H; Jaggi, Jurg L; Wong, Stephen

    2008-04-01

    Microelectrode recording during deep brain stimulation surgery is a useful adjunct for subthalamic nucleus (STN) localization. We hypothesize that information in the nonspike background activity can help identify STN boundaries. We present results from a novel quantitative analysis that accomplishes this goal. Thirteen consecutive microelectrode recordings were retrospectively analyzed. Spikes were removed from the recordings with an automated algorithm. The remaining "despiked" signals were converted via root mean square amplitude and curve length calculations into "feature profile" time series. Subthalamic nucleus boundaries determined by inspection, based on sustained deviations from baseline for each feature profile, were compared against those determined intraoperatively by the clinical neurophysiologist. Feature profile activity within STN exhibited a sustained rise in 10 of 13 tracks (77%). The sensitivity of STN entry was 60% and 90% for curve length and root mean square amplitude, respectively, when agreement within 0.5 mm of the neurophysiologist's prediction was used. Sensitivities were 70% and 100% for 1 mm accuracy. Exit point sensitivities were 80% and 90% for both features within 0.5 mm and 1.0 mm, respectively. Reproducible activity patterns in deep brain stimulation microelectrode recordings can allow accurate identification of STN boundaries. Quantitative analyses of this type may provide useful adjunctive information for electrode placement in deep brain stimulation surgery.

  12. One-pass deep brain stimulation of dentato-rubro-thalamic tract and subthalamic nucleus for tremor-dominant or equivalent type Parkinson's disease.

    PubMed

    Coenen, Volker Arnd; Rijntjes, Michel; Prokop, Thomas; Piroth, Tobias; Amtage, Florian; Urbach, Horst; Reinacher, Peter Christoph

    2016-04-01

    Refractory tremor in tremor-dominant (TD) or equivalent-type (EQT) idiopathic Parkinson's syndrome (IPS) poses the challenge of choosing the best target region to for deep brain stimulation (DBS). While the subthalamic nucleus is typically chosen in younger patients as the target for dopamine-responsive motor symptoms, it is more complicated if tremor does not (fully) respond under trial conditions. In this report, we present the first results from simultaneous bilateral DBS of the DRT (dentato-rubro-thalamic tract) and the subthalamic nucleus (STN) in two elderly patients with EQT and TD IPS and dopamine-refractory tremor. Two patients received bilateral octopolar DBS electrodes in the STN additionally traversing the DRT region. Achieved electrode positions were determined with helical CT, overlaid onto DTI tractography data, and compared with clinical data of stimulation response. Both patients showed immediate and sustained improvement of their tremor, bilaterally. The proposed approach appears to be safe and feasible and a combined stimulation of the two target regions was performed tailored to the patients' symptoms. Clinically, no neuropsychiatric effects were seen. Our pilot data suggest a viable therapeutic option to treat the subgroup of TD and EQT IPS and with tremor as the predominant symptom. A clinical study to further investigate this approach ( www.clinicaltrials.gov ; NCT02288468) is the focus of our ongoing research.

  13. Changes in regional blood flow induced by unilateral subthalamic nucleus stimulation in patients with Parkinson's disease.

    PubMed

    Tanei, Takafumi; Kajita, Yasukazu; Nihashi, Takashi; Kaneoke, Yoshiki; Takebayashi, Shigenori; Nakatsubo, Daisuke; Wakabayashi, Toshihiko

    2009-11-01

    Changes in regional cerebral blood flow (rCBF) induced by unilateral deep brain stimulation (DBS) of the subthalamic nucleus (STN) were investigated in 7 consecutive patients with Parkinson's disease, 4 men and 3 women (mean age 62.3 +/- 8.1 years), who underwent rCBF measurement by N-isopropyl-p-(iodine-123)-iodoamphetamine single photon emission computed tomography at rest before and after unilateral STN DBS preoperatively in the on-drug condition, and postoperatively in the on-drug and on-stimulation condition. Statistical parametric mapping was used to identify significant changes in rCBF from the preoperative to the postoperative conditions. rCBF was increased in the bilateral cingulate cortices and bilateral cerebellar hemispheres. rCBF was decreased in the bilateral medial frontal cortices and left superior temporal cortex. Unilateral STN DBS produced rCBF changes in the bilateral cingulate cortices, cerebellar hemispheres, and medial frontal cortices. These findings indicate that unilateral STN DBS affects rCBF in both hemispheres.

  14. Effects of Medication and Subthalamic Nucleus Deep Brain Stimulation on Tongue Movements in Speakers with Parkinson's Disease Using Electropalatography: A Pilot Study

    ERIC Educational Resources Information Center

    Hartinger, Mariam; Tripoliti, Elina; Hardcastle, William J.; Limousin, Patricia

    2011-01-01

    Parkinson's disease (PD) affects speech in the majority of patients. Subthalamic nucleus deep brain stimulation (STN-DBS) is particularly effective in reducing tremor and rigidity. However, its effect on speech is variable. The aim of this pilot study was to quantify the effects of bilateral STN-DBS and medication on articulation, using…

  15. Articulatory Closure Proficiency in Patients with Parkinson's Disease Following Deep Brain Stimulation of the Subthalamic Nucleus and Caudal Zona Incerta

    ERIC Educational Resources Information Center

    Karlsson, Fredrik; Olofsson, Katarina; Blomstedt, Patric; Linder, Jan; Nordh, Erik; van Doorn, Jan

    2014-01-01

    Purpose: The present study aimed at comparing the effects of deep brain stimulation (DBS) treatment of the subthalamic nucleus (STN) and the caudal zona incerta (cZi) on the proficiency in achieving oral closure and release during plosive production of people with Parkinson's disease. Method: Nineteen patients participated preoperatively and…

  16. Electric stimulation of the tuberomamillary nucleus affects epileptic activity and sleep-wake cycle in a genetic absence epilepsy model.

    PubMed

    Blik, Vitaliya

    2015-01-01

    Deep brain stimulation (DBS) is a promising approach for epilepsy treatment, but the optimal targets and parameters of stimulation are yet to be investigated. Tuberomamillary nucleus (TMN) is involved in EEG desynchronization-one of the proposed mechanisms for DBS action. We studied whether TMN stimulation could interfere with epileptic spike-wave discharges (SWDs) in WAG/Rij rats with inherited absence epilepsy and whether such stimulation would affect sleep-wake cycle. EEG and video registration were used to determine SWD occurrence and stages of sleep and wake during three-hours recording sessions. Stimulation (100Hz) was applied in two modes: closed-loop (with previously determined interruption threshold intensity) or open-loop mode (with 50% or 70% threshold intensity). Closed-loop stimulation successfully interrupted SWDs but elevated their number by 148 ± 54% compared to baseline. It was accompanied by increase in number of episodes but not total duration of both active and passive wakefulness. Open-loop stimulation with amplitude 50% threshold did not change measured parameters, though 70% threshold stimulation reduced SWDs number by 40 ± 9%, significantly raised the amount of active wakefulness and decreased the amount of both slow-wave and rapid eye movement sleep. These results suggest that the TMN is unfavorable as a target for DBS as its stimulation may cause alterations in sleep-wake cycle. A careful choosing of parameters and control of sleep-wake activity is necessary when applying DBS in epilepsy. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Cholinergic Oculomotor Nucleus Activity Is Induced by REM Sleep Deprivation Negatively Impacting on Cognition.

    PubMed

    Santos, Patrícia Dos; Targa, Adriano D S; Noseda, Ana Carolina D; Rodrigues, Lais S; Fagotti, Juliane; Lima, Marcelo M S

    2017-09-01

    Several efforts have been made to understand the involvement of rapid eye movement (REM) sleep for cognitive processes. Consolidation or retention of recognition memories is severely disrupted by REM sleep deprivation (REMSD). In this regard, pedunculopontine tegmental nucleus (PPT) and other brainstem nuclei, such as pontine nucleus (Pn) and oculomotor nucleus (OCM), appear to be candidates to take part in this REM sleep circuitry with potential involvement in cognition. Therefore, the objective of this study was to investigate a possible association between the performance of Wistar rats in a declarative memory and PPT, Pn, and OCM activities after different periods of REMSD. We examined c-Fos and choline acetyltransferase (ChaT) expressions as indicators of neuronal activity as well as a familiarity-based memory test. The animals were distributed in groups: control, REMSD, and sleep rebound (REB). At the end of the different REMSD (24, 48, 72, and 96 h) and REB (24 h) time points, the rats were immediately tested in the object recognition test and then the brains were collected. Results indicated that OCM neurons presented an increased activity, due to ChaT-labeling associated with REMSD that negatively correlated (r = -0.32) with the cognitive performance. This suggests the existence of a cholinergic compensatory mechanism within the OCM during REMSD. We also showed that 24 h of REMSD impacted similarly in memory, compared to longer periods of REMSD. These data extend the notion that REM sleep is influenced by areas other than PPT, i.e., Pn and OCM, which could be key players in both sleep processes and cognition.

  18. Apathy following Bilateral Deep Brain Stimulation of Subthalamic Nucleus in Parkinson's Disease: A Meta-Analysis

    PubMed Central

    Zhang, Xiaona

    2018-01-01

    Bilateral deep brain stimulation of subthalamic nucleus (STN-DBS) has proven effective in improving motor symptoms in Parkinson's disease (PD) patients. However, psychiatric changes after surgery are controversial. In this study, we specifically analyzed apathy following bilateral STN-DBS in PD patients using a meta-analysis. Relevant articles utilized for this study were obtained through literature search on PubMed, ScienceDirect, and Embase databases. The articles included were those contained both pre- and postsurgery apathy data acquired using the Starkstein Apathy Scale or Apathy Evaluation Scale with patient follow-up of at least three months. A total of 9 out of 86 articles were included in our study through this strict screening process. Standardized mean difference (SMD), that is, Cohen's d, with a 95% confidence interval (CI) was calculated to show the change. We found a significant difference between the presurgery stage and the postsurgery stage scores (SMD = 0.35, 95% CI: 0.17∼0.52, P < 0.001). STN-DBS seems to relatively worsen the condition of apathy, which may result from both the surgery target (subthalamic nucleus) and the reduction of dopaminergic medication. Further studies should focus on the exact mechanisms of possible postoperative apathy in the future.

  19. Identification of the subthalamic nucleus in deep brain stimulation surgery with a novel wavelet-derived measure of neural background activity

    PubMed Central

    Snellings, André; Sagher, Oren; Anderson, David J.; Aldridge, J. Wayne

    2016-01-01

    Object A wavelet-based measure was developed to quantitatively assess neural background activity taken during surgical neurophysiological recordings to localize the boundaries of the subthalamic nucleus during target localization for deep brain stimulator implant surgery. Methods Neural electrophysiological data was recorded from 14 patients (20 tracks, n = 275 individual recording sites) with dopamine-sensitive idiopathic Parkinson’s disease during the target localization portion of deep brain stimulator implant surgery. During intraoperative recording the STN was identified based upon audio and visual monitoring of neural firing patterns, kinesthetic tests, and comparisons between neural behavior and known characteristics of the target nucleus. The quantitative wavelet-based measure was applied off-line using MATLAB software to measure the magnitude of the neural background activity, and the results of this analysis were compared to the intraoperative conclusions. Wavelet-derived estimates were compared to power spectral density measures. Results The wavelet-derived background levels were significantly higher in regions encompassed by the clinically estimated boundaries of the STN than in surrounding regions (STN: 225 ± 61 μV vs. ventral to STN: 112 ± 32 μV, and dorsal to STN: 136 ± 66 μV). In every track, the absolute maximum magnitude was found within the clinically identified STN. The wavelet-derived background levels provided a more consistent index with less variability than power spectral density. Conclusions The wavelet-derived background activity assessor can be calculated quickly, requires no spike sorting, and can be reliably used to identify the STN with very little subjective interpretation required. This method may facilitate rapid intraoperative identification of subthalamic nucleus borders. PMID:19344225

  20. Parafascicular thalamic nucleus deep brain stimulation decreases NMDA receptor GluN1 subunit gene expression in the prefrontal cortex.

    PubMed

    Fernández-Cabrera, Mónica R; Selvas, Abraham; Miguéns, Miguel; Higuera-Matas, Alejandro; Vale-Martínez, Anna; Ambrosio, Emilio; Martí-Nicolovius, Margarita; Guillazo-Blanch, Gemma

    2017-04-21

    The rodent parafascicular nucleus (PFn) or the centromedian-parafascicular complex of primates is a posterior intralaminar nucleus of the thalamus related to cortical activation and maintenance of states of consciousness underlying attention, learning and memory. Deep brain stimulation (DBS) of the PFn has been proved to restore arousal and consciousness in humans and to enhance performance in learning and memory tasks in rats. The primary expected effect of PFn DBS is to induce plastic changes in target neurons of brain areas associated with cognitive function. In this study, Wistar rats were stimulated for 20mins in the PFn following a DBS protocol that had previously facilitated memory in rats. NMDA and GABA B receptor binding, and gene expression of the GluN1subunit of the NMDA receptor (NMDAR) were assessed in regions related to cognitive functions, such as the prefrontal cortex and hippocampus. The results showed that PFn DBS induced a decrease in NMDAR GluN1 subunit gene expression in the cingulate and prelimbic cortices, but no significant statistical differences were found in the density of NMDA or GABA B receptors in any of the analyzed regions. Taken together, our findings suggest a possible role for the NMDAR GluN1 subunit in the prefrontal cortex in the procognitive actions of the PFn DBS. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

  1. Interleaving subthalamic nucleus deep brain stimulation to avoid side effects while achieving satisfactory motor benefits in Parkinson disease

    PubMed Central

    Zhang, Shizhen; Zhou, Peizhi; Jiang, Shu; Wang, Wei; Li, Peng

    2016-01-01

    Abstract Background: Deep brain stimulation (DBS) of the subthalamic nucleus is an effective treatment for advanced Parkinson disease (PD). However, achieving ideal outcomes by conventional programming can be difficult in some patients, resulting in suboptimal control of PD symptoms and stimulation-induced adverse effects. Interleaving stimulation (ILS) is a newer programming technique that can individually optimize the stimulation area, thereby improving control of PD symptoms while alleviating stimulation-induced side effects after conventional programming fails to achieve the desired results. Methods: We retrospectively reviewed PD patients who received DBS programming during the previous 4 years in our hospital. We collected clinical and demographic data from 12 patients who received ILS because of incomplete alleviation of PD symptoms or stimulation-induced adverse effects after conventional programming had proven ineffective or intolerable. Appropriate lead location was confirmed with postoperative reconstruction images. The rationale and clinical efficacy of ILS was analyzed. Results: We divided our patients into 4 groups based on the following symptoms: stimulation-induced dysarthria and choreoathetoid dyskinesias, gait disturbance, and incomplete control of parkinsonism. After treatment with ILS, patients showed satisfactory improvement in PD symptoms and alleviation of stimulation-induced side effects, with a mean improvement in Unified PD Rating Scale motor scores of 26.9%. Conclusions: ILS is a newer choice and effective programming strategy to maximize symptom control in PD while decreasing stimulation-induced adverse effects when conventional programming fails to achieve satisfactory outcome. However, we should keep in mind that most DBS patients are routinely treated with conventional stimulation and that not all patients benefit from ILS. ILS is not recommended as the first choice of programming, and it is recommended only when patients have

  2. FGF–2 is required to prevent astrogliosis in the facial nucleus after facial nerve injury and mechanical stimulation of denervated vibrissal muscles

    PubMed Central

    Hizay, Arzu; Seitz, Mark; Grosheva, Maria; Sinis, Nektarios; Kaya, Yasemin; Bendella, Habib; Sarikcioglu, Levent; Dunlop, Sarah A.; Angelov, Doychin N.

    2016-01-01

    Abstract Recently, we have shown that manual stimulation of paralyzed vibrissal muscles after facial-facial anastomosis reduced the poly-innervation of neuromuscular junctions and restored vibrissal whisking. Using gene knock outs, we found a differential dependence of manual stimulation effects on growth factors. Thus, insulin-like growth factor-1 and brain-derived neurotrophic factor are required to underpin manual stimulation-mediated improvements, whereas FGF-2 is not. The lack of dependence on FGF-2 in mediating these peripheral effects prompted us to look centrally, i.e. within the facial nucleus where increased astrogliosis after facial-facial anastomosis follows "synaptic stripping". We measured the intensity of Cy3-fluorescence after immunostaining for glial fibrillary acidic protein (GFAP) as an indirect indicator of synaptic coverage of axotomized neurons in the facial nucleus of mice lacking FGF-2 (FGF-2-/- mice). There was no difference in GFAP-Cy3-fluorescence (pixel number, gray value range 17–103) between intact wildtype mice (2.12± 0.37×107) and their intact FGF-2-/- counterparts (2.12± 0.27×107) nor after facial-facial anastomosis +handling (wildtype: 4.06± 0.32×107; FGF-2-/-: 4.39±0.17×107). However, after facial-facial anastomosis, GFAP-Cy3-fluorescence remained elevated in FGF-2-/--animals (4.54±0.12×107), whereas manual stimulation reduced the intensity of GFAP-immunofluorescence in wild type mice to values that were not significantly different from intact mice (2.63± 0.39×10 ). We conclude that FGF-2 is not required to underpin the beneficial effects of manual stimulation at the neuro-muscular junction, but it is required to minimize astrogliosis in the brainstem and, by implication, restore synaptic coverage of recovering facial motoneurons. PMID:28276669

  3. Effects of medication and subthalamic nucleus deep brain stimulation on tongue movements in speakers with Parkinson's disease using electropalatography: a pilot study.

    PubMed

    Hartinger, Mariam; Tripoliti, Elina; Hardcastle, William J; Limousin, Patricia

    2011-03-01

    Parkinson's disease (PD) affects speech in the majority of patients. Subthalamic nucleus deep brain stimulation (STN-DBS) is particularly effective in reducing tremor and rigidity. However, its effect on speech is variable. The aim of this pilot study was to quantify the effects of bilateral STN-DBS and medication on articulation, using electropalatography (EPG). Two patients, PT1 and PT2, were studied under four conditions: on and off medication and ON and OFF stimulation. The EPG protocol consisted of a number of target words with alveolar and velar stops, repeated 10 times in random order. The motor part III of the Unified Parkinson Disease Rating Scale (UPDRS) indicated significantly improved motor scores in the ON stimulation condition in both patients. However, PT1's articulation patterns deteriorated with stimulation whereas PT2 showed improving articulatory accuracy in the same condition. The results revealed different effects of stimulation and medication on articulation particularly with regard to timing. The study quantified less articulatory undershoot for velar stops in comparison to alveolars. Furthermore, the findings provided preliminary evidence that stimulation with medication has a more detrimental effect on articulation than stimulation without medication.

  4. Validity of Single Tract Microelectrode Recording in Subthalamic Nucleus Stimulation

    PubMed Central

    Umemura, Atsushi; Oka, Yuichi; Yamada, Kazuo; Oyama, Genko; Shimo, Yasushi; Hattori, Nobutaka

    2013-01-01

    In surgery for subthalamic nucleus (STN) deep brain stimulation (DBS), precise implantation of the lead into the STN is essential. Physiological refinement with microelectrode recording (MER) is the gold standard for identifying STN. We studied single tract MER findings and surgical outcomes and verified our surgical method using single tract MER. The number of trajectories in MER and the final position of lead placement were retrospectively analyzed in 440 sides of STN DBS in 221 patients. Bilateral STN DBS yielded marked improvement in the motor score, dyskinesia/fluctuation score, and reduced requirement of dopaminergic medication in this series. The number of trajectories required to obtain sufficient activity of the STN was one in 79.0%, two in 18.2%, and three or more in 2.5% of 440 sides. In 92 sides requiring altered trajectory, the final direction of trajectory movement was posterior in 73.9%, anterior in 13.0%, lateral in 5.4%, and medial in 4.3%. In 18 patients, posterior moves were required due to significant brain shift with intracranial air caused by outflow of CSF during the second side procedure. Sufficient STN activity is obtained with minimum trajectories by proper targeting and precise interpretation of MER findings even in the single tract method. Anterior–posterior moves rather than medial–lateral moves should be attempted first in cases with insufficient recording of STN activity. PMID:24140767

  5. Nigral stimulation for resistant axial motor impairment in Parkinson's disease? A randomized controlled trial.

    PubMed

    Weiss, Daniel; Walach, Margarete; Meisner, Christoph; Fritz, Melanie; Scholten, Marlieke; Breit, Sorin; Plewnia, Christian; Bender, Benjamin; Gharabaghi, Alireza; Wächter, Tobias; Krüger, Rejko

    2013-07-01

    Gait and balance disturbances typically emerge in advanced Parkinson's disease with generally limited response to dopaminergic medication and subthalamic nucleus deep brain stimulation. Therefore, advanced programming with interleaved pulses was put forward to introduce concomittant nigral stimulation on caudal contacts of a subthalamic lead. Here, we hypothesized that the combined stimulation of subthalamic nucleus and substantia nigra pars reticulata improves axial symptoms compared with standard subthalamic nucleus stimulation. Twelve patients were enrolled in this 2 × 2 cross-over double-blind randomized controlled clinical trial and both the safety and efficacy of combined subthalamic nucleus and substantia nigra pars reticulata stimulation were evaluated compared with standard subthalamic nucleus stimulation. The primary outcome measure was the change of a broad-scaled cumulative axial Unified Parkinson's Disease Rating Scale score (Scale II items 13-15, Scale III items 27-31) at '3-week follow-up'. Secondary outcome measures specifically addressed freezing of gait, balance, quality of life, non-motor symptoms and neuropsychiatric symptoms. For the primary outcome measure no statistically significant improvement was observed for combined subthalamic nucleus and substantia nigra pars reticulata stimulation at the '3-week follow-up'. The secondary endpoints, however, revealed that the combined stimulation of subthalamic nucleus and substantia nigra pars reticulata might specifically improve freezing of gait, whereas balance impairment remained unchanged. The combined stimulation of subthalamic nucleus and substantia nigra pars reticulata was safe, and of note, no clinically relevant neuropsychiatric adverse effect was observed. Patients treated with subthalamic nucleus and substantia nigra pars reticulata stimulation revealed no 'global' effect on axial motor domains. However, this study opens the perspective that concomittant stimulation of the substantia

  6. Successful deep brain stimulation of the nucleus accumbens in severe alcohol dependence is associated with changed performance monitoring.

    PubMed

    Kuhn, Jens; Gründler, Theo O J; Bauer, Robert; Huff, Wolfgang; Fischer, Adrian G; Lenartz, Doris; Maarouf, Mohammad; Bührle, Christian; Klosterkötter, Joachim; Ullsperger, Markus; Sturm, Volker

    2011-10-01

    Following recent advances in neuromodulation therapy for mental disorders, we treated one patient with severe alcohol addiction with deep brain stimulation (DBS) of the nucleus accumbens (NAc). Before and one year following the surgery, we assessed the effects of DBS within the NAc on the addiction as well as on psychometric scores and electrophysiological measures of cognitive control. In our patient, DBS achieved normalization of addictive behavior and craving. An electrophysiological marker of error processing (the error-related negativity) linked to anterior mid-cingulate cortex (aMCC) functioning was altered through DBS, an effect that could be reversed by periods without stimulation. Thus, this case supports the hypothesis that DBS of the NAc could have a positive effect on addiction trough a normalization of craving associated with aMCC dysfunction. © 2011 The Authors, Addiction Biology © 2011 Society for the Study of Addiction.

  7. [Effect of stimulation of GABA-ergic structures of the substantia nigra and caudate nucleus on food-getting behavior in the cat].

    PubMed

    Shugalev, N P

    1983-01-01

    A study was made of the functional significance of GABA-ergic structures of the substantia nigra (SN) and the caudate nucleus (CN) and their role in food-procuring behaviour of cats. Analysis was made of behavioral and EEG-effects of local GABA and the GABA antagonist, picrotoxin, microinjections into the studied brain structures. Stimulation of the GABA-ergic structures of the SN produced a sedative effect and depression of the cat food-procuring behaviour. Effects of stimulation of the CN GABA-ergic structures were to a great degree reverse. The conclusion has been made that GABA-ergic structures of the SN and the CN play different roles in controlling the CN inhibitory influence upon food-procuring behaviour.

  8. Notochordal cell conditioned medium stimulates mesenchymal stem cell differentiation toward a young nucleus pulposus phenotype

    PubMed Central

    2010-01-01

    Introduction Mesenchymal stem cells (MSCs) offer promise for intervertebral disc (IVD) repair and regeneration because they are easily isolated and expanded, and can differentiate into several mesenchymal tissues. Notochordal (NC) cells contribute to IVD development, incorporate into the nucleus pulposus (NP), and stimulate mature disc cells. However, there have been no studies investigating the effects of NC cells on adult stem cell differentiation. The premise of this study is that IVD regeneration is more similar to IVD development than to IVD maintenance, and we hypothesize that soluble factors from NC cells differentiate MSCs to a phenotype characteristic of nucleus pulposus (NP) cells during development. The eventual clinical goal would be to isolate or chemically/recombinantly produce the active agent to induce the therapeutic effects, and to use it as either an injectable therapy for early intervention on disc disease, or in developing appropriately pre-differentiated MSC cells in a tissue engineered NP construct. Methods Human MSCs from bone marrow were expanded and pelleted to form high-density cultures. MSC pellets were exposed to either control medium (CM), chondrogenic medium (CM with dexamethasone and transforming growth factor, (TGF)-β3) or notochordal cell conditioned medium (NCCM). NCCM was prepared from NC cells maintained in serum free medium for four days. After seven days culture, MSC pellets were analyzed for appearance, biochemical composition (glycosaminoglycans and DNA), and gene expression profile (sox-9, collagen types-II and III, laminin-β1 and TIMP1(tissue inhibitor of metalloproteinases-1)). Results Significantly higher glycosaminoglycan accumulation was seen in NCCM treated pellets than in CM or TGFβ groups. With NCCM treatment, increased gene expression of collagen III, and a trend of increasing expression of laminin-β1 and decreased expression of sox-9 and collagen II relative to the TGFβ group was observed. Conclusions

  9. Stimulation of subterritories of the subthalamic nucleus reveals its role in the integration of the emotional and motor aspects of behavior

    PubMed Central

    Mallet, Luc; Schüpbach, Michael; N'Diaye, Karim; Remy, Philippe; Bardinet, Eric; Czernecki, Virginie; Welter, Marie-Laure; Pelissolo, Antoine; Ruberg, Merle; Agid, Yves; Yelnik, Jérôme

    2007-01-01

    Two parkinsonian patients who experienced transient hypomanic states when the subthalamic nucleus (STN) was stimulated during postoperative adjustment of the electrical parameters for antiparkinsonian therapy agreed to have the mood disorder reproduced, in conjunction with motor, cognitive, and behavioral evaluations and concomitant functional neuroimaging. During the experiment, STN stimulation again induced a hypomanic state concomitant with activation of cortical and thalamic regions known to process limbic and associative information. This observation suggests that the STN plays a role in the control of a complex behavior that includes emotional as well as cognitive and motor components. The localization of the four contacts of the quadripolar electrode was determined precisely with an interactive brain atlas. The results showed that (i) the hypomanic state was caused only by stimulation through one contact localized in the anteromedial STN; (ii) both this contact and the contact immediately dorsal to it improved the parkinsonian motor state; (iii) the most dorsal and ventral contacts, located at the boundaries of the STN, neither induced the behavioral disorder nor improved motor performance. Detailed analysis of these data led us to consider a model in which the three functional modalities, emotional, cognitive, and motor, are not processed in a segregated manner but can be subtly combined in the small volume of the STN. This nucleus would thus serve as a nexus that integrates the motor, cognitive, and emotional components of behavior and might consequently be an effective target for the treatment of behavioral disorders that combine emotional, cognitive, and motor impairment. PMID:17556546

  10. Deep brain stimulation of the subthalamic nucleus modulates reward processing and action selection in Parkinson patients.

    PubMed

    Wagenbreth, Caroline; Zaehle, Tino; Galazky, Imke; Voges, Jürgen; Guitart-Masip, Marc; Heinze, Hans-Jochen; Düzel, Emrah

    2015-06-01

    Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is an effective treatment for motor impairments in Parkinson's disease (PD) but its effect on the motivational regulation of action control is still not fully understood. We investigated whether DBS of the STN influences the ability of PD patients to act for anticipated reward or loss, or whether DBS improves action execution independent of motivational valence. 16 PD patients (12 male, mean age = 58.5 ± 10.17 years) treated with bilateral STN-DBS and an age- and gender-matched group of healthy controls (HC) performed a go/no-go task whose contingencies explicitly decouple valence and action. Patients were tested with (ON) and without (OFF) active STN stimulation. For HC, there was a benefit in performing rewarded actions when compared to actions that avoided punishment. PD patients showed such a benefit reliably only when STN stimulation was ON. In fact, the relative behavioral benefit for go for reward over go to avoid losing was stronger in the PD patients under DBS ON than in HC. In PD patients, rather than generally improving motor functions independent of motivational valence, modulation of the STN by DBS improves action execution specifically when rewards are anticipated. Thus, STN-DBS establishes a reliable congruency between action and reward ("Pavlovian congruency") and remarkably enhances it over the level observed in HC.

  11. Effects of deep brain stimulation of the subthalamic nucleus on perceptual decision making.

    PubMed

    Zaehle, Tino; Wagenbreth, Caroline; Voges, Jürgen; Heinze, Hans-Jochen; Galazky, Imke

    2017-02-20

    When faced with difficult decisions, people prefer to stay with the default. This status quo bias often leads to suboptimal choice behavior. Neurophysiological evidence suggests a pivot role of the Subthalamic Nucleus (STN) for overcoming such status quo bias in difficult decisions, but causal evidence is lacking. The present study investigated whether subthalamic deep brain stimulation (DBS) in patients with Parkinson's disease (PD) influences the status quo bias. Eighteen PD patients treated with STN-DBS performed a difficult perceptual decision task incorporating intrinsic status quo option. Patients were tested with (ON) and without (OFF) active STN stimulation. Our results show that DBS of the STN affected perceptual decision making in PD patients depending on the difficulty of decision. STN-DBS improved difficult perceptual decisions due to a selective increase in accuracy (hit rate) that was independent of response bias (no effect on false alarm rate). Furthermore, STN-DBS impacted status quo bias as a function of baseline impulsivity. In impulsive patients, STN-DBS increased the default bias, whereas in less impulsive PD patients, DBS of the STN reduced the status quo bias. In line with our hypothesis, STN-DBS selectively affected the tendency to stick with the default option on difficult decisions, and promoted increased decision accuracy. Moreover, we demonstrate the impact of baseline cognitive abilities on DBS-related performance changes in PD patients. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

  12. Stimulation sites in the subthalamic nucleus projected onto a mean 3-D atlas of the thalamus and basal ganglia.

    PubMed

    Sarnthein, Johannes; Péus, Dominik; Baumann-Vogel, Heide; Baumann, Christian R; Sürücü, Oguzkan

    2013-09-01

    In patients with severe forms of Parkinson's disease (PD), deep brain stimulation (DBS) commonly targets the subthalamic nucleus (STN). Recently, the mean 3-D Morel-Atlas of the basal ganglia and the thalamus was introduced. It combines information contained in histological data from ten post-mortem brains. We were interested whether the Morel-Atlas is applicable for the visualization of stimulation sites. In a consecutive PD patient series, we documented preoperative MRI planning, intraoperative target adjustment based on electrophysiological and neurological testing, and perioperative CT target reconstruction. The localization of the DBS electrodes and the optimal stimulation sites were projected onto the Morel-Atlas. We included 20 patients (median age 62 years). The active contact had mean coordinates Xlat = ±12.1 mm, Yap = -1.8 mm, Zvert = -3.2 mm. There was a significant difference between the initially planned site and the coordinates of the postoperative active contact site (median 2.2 mm). The stimulation site was, on average, more anterior and more dorsal. The electrode contact used for optimal stimulation was found within the STN of the atlas in 38/40 (95 %) of implantations. The cluster of stimulation sites in individual patients-as deduced from preoperative MR, intraoperative electrophysiology and neurological testing-showed a high degree of congruence with the atlas. The mean 3D Morel Atlas is thus a useful tool for postoperative target visualization. This represents the first clinical evaluation of the recently created atlas.

  13. Nigral stimulation for resistant axial motor impairment in Parkinson’s disease? A randomized controlled trial

    PubMed Central

    Walach, Margarete; Meisner, Christoph; Fritz, Melanie; Scholten, Marlieke; Breit, Sorin; Plewnia, Christian; Bender, Benjamin; Gharabaghi, Alireza; Wächter, Tobias

    2013-01-01

    Gait and balance disturbances typically emerge in advanced Parkinson’s disease with generally limited response to dopaminergic medication and subthalamic nucleus deep brain stimulation. Therefore, advanced programming with interleaved pulses was put forward to introduce concomittant nigral stimulation on caudal contacts of a subthalamic lead. Here, we hypothesized that the combined stimulation of subthalamic nucleus and substantia nigra pars reticulata improves axial symptoms compared with standard subthalamic nucleus stimulation. Twelve patients were enrolled in this 2 × 2 cross-over double-blind randomized controlled clinical trial and both the safety and efficacy of combined subthalamic nucleus and substantia nigra pars reticulata stimulation were evaluated compared with standard subthalamic nucleus stimulation. The primary outcome measure was the change of a broad-scaled cumulative axial Unified Parkinson’s Disease Rating Scale score (Scale II items 13–15, Scale III items 27–31) at ‘3-week follow-up’. Secondary outcome measures specifically addressed freezing of gait, balance, quality of life, non-motor symptoms and neuropsychiatric symptoms. For the primary outcome measure no statistically significant improvement was observed for combined subthalamic nucleus and substantia nigra pars reticulata stimulation at the ‘3-week follow-up’. The secondary endpoints, however, revealed that the combined stimulation of subthalamic nucleus and substantia nigra pars reticulata might specifically improve freezing of gait, whereas balance impairment remained unchanged. The combined stimulation of subthalamic nucleus and substantia nigra pars reticulata was safe, and of note, no clinically relevant neuropsychiatric adverse effect was observed. Patients treated with subthalamic nucleus and substantia nigra pars reticulata stimulation revealed no ‘global’ effect on axial motor domains. However, this study opens the perspective that concomittant stimulation

  14. Cognition following bilateral deep brain stimulation surgery of the subthalamic nucleus for Parkinson's disease.

    PubMed

    Halpern, Casey H; Rick, Jacqueline H; Danish, Shabbar F; Grossman, Murray; Baltuch, Gordon H

    2009-05-01

    Parkinson's disease (PD) is a neurodegenerative disorder characterized by significant motor dysfunction and various non-motor disturbances, including cognitive alterations. Deep brain stimulation (DBS) is an increasingly utilized therapeutic option for patients with PD that yields remarkable success in alleviating disabling motor symptoms. DBS has additionally been associated with changes in cognition, yet the evidence is not consistent across studies. The following review sought to provide a clearer understanding of the various cognitive sequelae of bilateral subthalamic nucleus (STN) DBS while taking into account corresponding neuroanatomy and potential confounding variables. A literature search was performed using the following inclusion criteria: (1) at least five subjects followed for a mean of at least 3 months after surgery; (2) pre- and postoperative cognitive data using at least one standardized measure; (3) adequate report of study results using means and standard deviations. Two recent meta-analyses found mild post-operative impairments in verbal learning and executive function in patients who underwent DBS surgery. However, studies have revealed improved working memory and psychomotor speed in the 'on' vs 'off' stimulation state. A deficit in language may be a consequence of the surgical procedure. While cognitive decline has been observed in some domains, our review of the data suggests that STN DBS is a worthwhile and safe method to treat PD. (c) 2008 John Wiley & Sons, Ltd.

  15. Deep Brain Stimulation of the Subthalamic Nucleus Improves Lexical Switching in Parkinsons Disease Patients.

    PubMed

    Vonberg, Isabelle; Ehlen, Felicitas; Fromm, Ortwin; Kühn, Andrea A; Klostermann, Fabian

    2016-01-01

    Reduced verbal fluency (VF) has been reported in patients with Parkinson's disease (PD), especially those treated by Deep Brain Stimulation of the subthalamic nucleus (STN DBS). To delineate the nature of this dysfunction we aimed at identifying the particular VF-related operations modified by STN DBS. Eleven PD patients performed VF tasks in their STN DBS ON and OFF condition. To differentiate VF-components modulated by the stimulation, a temporal cluster analysis was performed, separating production spurts (i.e., 'clusters' as correlates of automatic activation spread within lexical fields) from slower cluster transitions (i.e., 'switches' reflecting set-shifting towards new lexical fields). The results were compared to those of eleven healthy control subjects. PD patients produced significantly more switches accompanied by shorter switch times in the STN DBS ON compared to the STN DBS OFF condition. The number of clusters and time intervals between words within clusters were not affected by the treatment state. Although switch behavior in patients with DBS ON improved, their task performance was still lower compared to that of healthy controls. Beyond impacting on motor symptoms, STN DBS seems to influence the dynamics of cognitive procedures. Specifically, the results are in line with basal ganglia roles for cognitive switching, in the particular case of VF, from prevailing lexical concepts to new ones.

  16. Deep brain stimulation of the nucleus accumbens shell attenuates cue-induced reinstatement of both cocaine and sucrose seeking in rats.

    PubMed

    Guercio, Leonardo A; Schmidt, Heath D; Pierce, R Christopher

    2015-03-15

    Stimuli previously associated with drug taking can become triggers that can elicit craving and lead to relapse of drug-seeking behavior. Here, we examined the influence of deep brain stimulation (DBS) in the nucleus accumbens shell on cue-induced reinstatement of cocaine seeking, an animal model of relapse. Rats were allowed to self-administer cocaine (0.254 mg, i.v.) for 2 h daily for 21 days, with each infusion of cocaine being paired with a cue light. After 21 days of self-administration, cocaine-taking behavior was extinguished by replacing cocaine with saline in the absence of the cue light. Next, during the reinstatement phase, DBS was administered bilaterally into the nucleus accumbens shell through bipolar stainless steel electrodes immediately prior to re-exposure to cues previously associated with cocaine reinforcement. DBS continued throughout the 2 h reinstatement session. Parallel studies examined the influence of accumbens shell DBS on reinstatement induced by cues previously associated with sucrose reinforcement. Results indicated that DBS of the nucleus accumbens shell significantly attenuated cue-induced reinstatement of cocaine and sucrose seeking. Together, these results indicate that DBS of the accumbens shell disrupts cue-induced reinstatement associated with both a drug and a natural reinforcer. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. High-frequency stimulation of the globus pallidus interna nucleus modulates GFRα1 gene expression in the basal ganglia.

    PubMed

    Ho, Duncun Xun Kiat; Tan, Yong Chee; Tan, Jiayi; Too, Heng Phon; Ng, Wai Hoe

    2014-04-01

    Deep brain stimulation (DBS) is an established therapy for movement disorders such as Parkinson's disease (PD). Although the efficacy of DBS is clear, its precise molecular mechanism remains unknown. The glial cell line derived factor (GDNF) family of ligands has been shown to confer neuroprotective effects on dopaminergic neurons, and putaminal infusion of GDNF have been investigated in PD patients with promising results. Despite the potential therapeutic role of GDNF in alleviating motor symptoms, there is no data on the effects of electrical stimulation on GDNF-family receptor (GFR) expression in the basal ganglia structures. Here, we report the effects of electrical stimulation on GFRα1 isoforms, particularly GFRα1a and GFRα1b. Wistar rats underwent 2 hours of high frequency stimulation (HFS) at the globus pallidus interna nucleus. A control group was subjected to a similar procedure but without stimulation. The HFS group, sacrificed 24 hours after treatment, had a threefold decrease in mRNA expression level of GFRα1b (p=0.037), but the expression level reverted to normal 72 hours after stimulation. Our preliminary data reveal the acute effects of HFS on splice isoforms of GFRα1, and suggest that HFS may modulate the splice isoforms of GFRα1a and GFRα1b to varying degrees. Going forward, elucidating the interactions between HFS and GFR may shed new insights into the complexity of GDNF signaling in the nervous system and lead to better design of clinical trials using these signaling pathways to halt disease progression in PD and other neurodegenerative diseases. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. The effects of bilateral stimulation of the subthalamic nucleus on heart rate variability in patients with Parkinson's disease.

    PubMed

    Liu, Kang-Du; Shan, Din-E; Kuo, Terry B J; Yang, Cheryl C H

    2013-07-01

    The beneficial effects of subthalamic nucleus deep brain stimulation (STN-DBS) on motor symptoms and quality of life in Parkinson's disease (PD) are well known, but little is known of the effects on autonomic function. Diffusion of current during stimulation of the STN may simultaneously involve the motor and nonmotor, limbic and associative areas of the STN. The aims of this study were to examine whether STN stimulation affects functions of the autonomic nervous system and, if so, to correlate the effects with the active contacts of electrodes in the STN. Eight PD patients with good motor control and quality of sleep after STN-DBS surgery were recruited. All patients had two days of recordings with portable polysomnography (PSG) (first night with stimulation "on" and second night "off"). From the PSG data, the first sleep cycle of each recording night was defined. Heart rate variability (HRV) was analyzed between the same uninterrupted periods of the two sleep nights. In addition, the optimal electrode positions were defined from postoperative MRI studies, and the coordinates of active contacts were confirmed. HRV spectral analysis showed that only low-frequency (LF)/high-frequency (HF) power was significantly activated in the stimulation "on" groups (P = 0.011). There was a significant negative correlation between power change of LF/HF and electrode position lateral to the midcommissural point (ρ = 0.857, P = 0.007) These results demonstrate that STN-DBS can enhance sympathetic regulation; the autonomic response may be due to electrical signals being distributed to limbic components of the STN or descending sympathetic pathways in the zona incerta.

  19. Deep brain stimulation modulates synchrony within spatially and spectrally distinct resting state networks in Parkinson's disease.

    PubMed

    Oswal, Ashwini; Beudel, Martijn; Zrinzo, Ludvic; Limousin, Patricia; Hariz, Marwan; Foltynie, Tom; Litvak, Vladimir; Brown, Peter

    2016-05-01

    Chronic dopamine depletion in Parkinson's disease leads to progressive motor and cognitive impairment, which is associated with the emergence of characteristic patterns of synchronous oscillatory activity within cortico-basal-ganglia circuits. Deep brain stimulation of the subthalamic nucleus is an effective treatment for Parkinson's disease, but its influence on synchronous activity in cortico-basal-ganglia loops remains to be fully characterized. Here, we demonstrate that deep brain stimulation selectively suppresses certain spatially and spectrally segregated resting state subthalamic nucleus-cortical networks. To this end we used a validated and novel approach for performing simultaneous recordings of the subthalamic nucleus and cortex using magnetoencephalography (during concurrent subthalamic nucleus deep brain stimulation). Our results highlight that clinically effective subthalamic nucleus deep brain stimulation suppresses synchrony locally within the subthalamic nucleus in the low beta oscillatory range and furthermore that the degree of this suppression correlates with clinical motor improvement. Moreover, deep brain stimulation relatively selectively suppressed synchronization of activity between the subthalamic nucleus and mesial premotor regions, including the supplementary motor areas. These mesial premotor regions were predominantly coupled to the subthalamic nucleus in the high beta frequency range, but the degree of deep brain stimulation-associated suppression in their coupling to the subthalamic nucleus was not found to correlate with motor improvement. Beta band coupling between the subthalamic nucleus and lateral motor areas was not influenced by deep brain stimulation. Motor cortical coupling with subthalamic nucleus predominantly involved driving of the subthalamic nucleus, with those drives in the higher beta frequency band having much shorter net delays to subthalamic nucleus than those in the lower beta band. These observations raise the

  20. Stimulation of the Rat Subthalamic Nucleus is Neuroprotective Following Significant Nigral Dopamine Neuron Loss

    PubMed Central

    Spieles-Engemann, A. L.; Behbehani, M. M.; Collier, T. J.; Wohlgenant, S. L.; Steece-Collier, K.; Paumier, K.; Daley, B. F.; Gombash, S.; Madhavan, L.; Mandybur, G. T.; Lipton, J.W.; Terpstra, B.T.; Sortwell, C.E.

    2010-01-01

    Deep brain stimulation of the subthalamic nucleus (STN-DBS) is efficacious in treating the motor symptoms of Parkinson’s disease (PD). However, the impact of STN-DBS on the progression of PD is unknown. Previous preclinical studies have demonstrated that STN-DBS can attenuate the degeneration of a relatively intact nigrostriatal system from dopamine (DA)-depleting neurotoxins. The present study examined whether STN-DBS can provide neuroprotection in the face of prior significant nigral DA neuron loss similar to PD patients at the time of diagnosis. STN-DBS between two and four weeks after intrastriatal 6-hydroxydopamine (6-OHDA) provided significant sparing of DA neurons in the SN of rats. This effect was not due to inadvertent lesioning of the STN and was dependent upon proper electrode placement. Since STN-DBS appears to have significant neuroprotective properties, initiation of STN-DBS earlier in the course of PD may provide added neuroprotective benefits in addition to its ability to provide symptomatic relief. PMID:20307668

  1. Deep brain stimulation modulates synchrony within spatially and spectrally distinct resting state networks in Parkinson’s disease

    PubMed Central

    Oswal, Ashwini; Beudel, Martijn; Zrinzo, Ludvic; Limousin, Patricia; Hariz, Marwan; Foltynie, Tom; Litvak, Vladimir

    2016-01-01

    Abstract Chronic dopamine depletion in Parkinson’s disease leads to progressive motor and cognitive impairment, which is associated with the emergence of characteristic patterns of synchronous oscillatory activity within cortico-basal-ganglia circuits. Deep brain stimulation of the subthalamic nucleus is an effective treatment for Parkinson’s disease, but its influence on synchronous activity in cortico-basal-ganglia loops remains to be fully characterized. Here, we demonstrate that deep brain stimulation selectively suppresses certain spatially and spectrally segregated resting state subthalamic nucleus–cortical networks. To this end we used a validated and novel approach for performing simultaneous recordings of the subthalamic nucleus and cortex using magnetoencephalography (during concurrent subthalamic nucleus deep brain stimulation). Our results highlight that clinically effective subthalamic nucleus deep brain stimulation suppresses synchrony locally within the subthalamic nucleus in the low beta oscillatory range and furthermore that the degree of this suppression correlates with clinical motor improvement. Moreover, deep brain stimulation relatively selectively suppressed synchronization of activity between the subthalamic nucleus and mesial premotor regions, including the supplementary motor areas. These mesial premotor regions were predominantly coupled to the subthalamic nucleus in the high beta frequency range, but the degree of deep brain stimulation-associated suppression in their coupling to the subthalamic nucleus was not found to correlate with motor improvement. Beta band coupling between the subthalamic nucleus and lateral motor areas was not influenced by deep brain stimulation. Motor cortical coupling with subthalamic nucleus predominantly involved driving of the subthalamic nucleus, with those drives in the higher beta frequency band having much shorter net delays to subthalamic nucleus than those in the lower beta band. These

  2. Voice Tremor Outcomes of Subthalamic Nucleus and Zona Incerta Deep Brain Stimulation in Patients With Parkinson Disease.

    PubMed

    Karlsson, Fredrik; Malinova, Elin; Olofsson, Katarina; Blomstedt, Patric; Linder, Jan; Nordh, Erik

    2018-01-17

    We aimed to study the effect of deep brain stimulation (DBS) in the subthalamic nucleus (STN) and caudal zona incerta (cZi) on level of perceived voice tremor in patients with Parkinson disease (PD). This is a prospective nonrandomized design with consecutive patients. Perceived voice tremor was assessed in patients with PD having received either STN-DBS (8 patients, 5 bilateral and 3 unilateral, aged 43.1-73.6 years; median = 61.2 years) or cZi-DBS (14 bilateral patients, aged 39.0-71.9 years; median = 56.6 years) 12 months before the assessment. Sustained vowels that were produced OFF and ON stimulation (with simultaneous l-DOPA medication) were assessed perceptually in terms of voice tremor by two raters on a four-point rating scale. The assessments were repeated five times per sample and rated in a blinded and randomized procedure. Three out of the 22 patients (13%) were concluded to have voice tremor OFF stimulation. Patients with PD with STN-DBS showed mild levels of perceived voice tremor OFF stimulation and a group level improvement. Patients with moderate/severe perceived voice tremor and cZi-DBS showed marked improvements, but there was no overall group effect. Six patients with cZi-DBS showed small increases in perceived voice tremor severity. STN-DBS decreased perceived voice tremor on a group level. cZi-DBS decreased perceived voice tremor in patients with PD with moderate to severe preoperative levels of the symptom. Copyright © 2017 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

  3. Ventrolateral Motor Thalamus Abnormal Connectivity in Essential Tremor Before and After Thalamotomy: A Resting-State Functional Magnetic Resonance Imaging Study.

    PubMed

    Tuleasca, Constantin; Najdenovska, Elena; Régis, Jean; Witjas, Tatiana; Girard, Nadine; Champoudry, Jérôme; Faouzi, Mohamed; Thiran, Jean-Philippe; Cuadra, Meritxell Bach; Levivier, Marc; Van De Ville, Dimitri

    2018-05-01

    To evaluate functional connectivity (FC) of the ventrolateral thalamus, a common target for drug-resistant essential tremor (ET), resting-state data were analyzed before and 1 year after stereotactic radiosurgical thalamotomy and compared against healthy controls (HCs). In total, 17 consecutive patients with ET and 10 HCs were enrolled. Tremor network was investigated using the ventrolateral ventral (VLV) thalamic nucleus as the region of interest, extracted with automated segmentation from pretherapeutic diffusion magnetic resonance imaging. Temporal correlations of VLV at whole brain level were evaluated by comparing drug-naïve patients with ET with HCs, and longitudinally, 1 year after stereotactic radiosurgical thalamotomy. 1 year thalamotomy MR signature was always located inside VLV and did not correlate with any of FC measures (P > 0.05). This suggested presence of longitudinal changes in VLV FC independently of the MR signature volume. Pretherapeutic ET displayed altered VLV FC with left primary sensory-motor cortex, pedunculopontine nucleus, dorsal anterior cingulate, left visual association, and left superior parietal areas. Pretherapeutic negative FC with primary somatosensory cortex and pedunculopontine nucleus correlated with poorer baseline tremor scores (Spearman = 0.04 and 0.01). Longitudinal study displayed changes within right dorsal attention (frontal eye-fields and posterior parietal) and salience (anterior insula) networks, as well as areas involved in hand movement planning or language production. Our results demonstrated that patients with ET and HCs differ in their left VLV FC to primary somatosensory and supplementary motor, visual association, or brainstem areas (pedunculopontine nucleus). Longitudinal changes display reorganization of dorsal attention and salience networks after thalamotomy. Beside attentional gateway, they are also known for their major role in facilitating a rapid access to the motor system. Copyright © 2018 Elsevier

  4. MRI directed bilateral stimulation of the subthalamic nucleus in patients with Parkinson's disease

    PubMed Central

    Patel, N; Plaha, P; O'Sullivan, K; McCarter, R; Heywood, P; Gill, S

    2003-01-01

    Objective: Bilateral chronic high frequency deep brain stimulation (DBS) of the subthalamic nucleus (STN) has emerged as an appropriate therapy for patients with advanced Parkinson's disease refractory to medical therapy. Advances in neuroimaging and neurophysiology have led to the development of varied targeting methods for the delivery of this treatment. Intraoperative neurophysiological and clinical monitoring is regarded by many to be mandatory for accurate STN localisation. We have examined efficacy of bilateral STN stimulation using a predominantly magnetic resonance imaging (MRI)-directed technique. Methods: DBS leads were stereotactically implanted into the STN using an MRI directed method, with intraoperative macrostimulation used purely for adjustment. The effects of DBS were evaluated in 16 patients followed up to 12 months, and compared with baseline assessments. Assessments were performed in both off and on medication states, and were based on the Unified Parkinson's Disease Rating Scale (UPDRS) and timed motor tests. Functional status outcomes were examined using the PDQ-39 quality of life questionnaire. A battery of psychometric tests was used to assess cognition. Results: After 12 months, stimulation in the off medication state resulted in significant improvements in Activities of Daily Living and Motor scores (UPDRS parts II and III) by 62% and 61% respectively. Timed motor tests were significantly improved in the off medication state. Motor scores (UPDRS part III) were significantly improved by 40% in the on medication state. Dyskinesias and off duration were significantly reduced and the mean dose of L-dopa equivalents was reduced by half. Psychometric test scores were mostly unchanged or improved. Adverse events were few. Conclusions: An MRI directed targeting method for implantation of DBS leads into the STN can be used safely and effectively, and results are comparable with studies using intraoperative microelectrode neurophysiological

  5. An alarm pheromone reduces ventral tegmental area-nucleus accumbens shell responsivity.

    PubMed

    Gutiérrez-García, Ana G; Contreras, Carlos M; Saldivar-Lara, Mauricio

    2018-06-21

    2-Heptanone (methyl n-amyl ketone) is a ketone that produces alarm reactions in insects (e.g., bees and ants). As an olfactory stimulus, 2-heptanone produces anxiety reactions in the short term and despair in the long term in rodent models. Among the anatomical connections of the olfactory system that integrate behavioral responses, connections between the amygdala and nucleus accumbens are important, which in turn form a circuit with the ventral tegmental area (VTA). 2-Heptanone increases the firing rate of amygdala neurons without participation of the vomeronasal organ. The olfactory amygdala-VTA-nucleus accumbens circuit may integrate defensive behaviors, but the possible actions of 2-heptanone on the responsivity of VTA-nucleus accumbens connections have not yet been explored. In the present study, multiunit activity recordings were obtained in adult Wistar rats from the core and shell subregions of the nucleus accumbens during electrical stimulation of the VTA under basal conditions and later during simultaneous stimulation of the VTA and olfactory exposure to 2-heptanone. 2-Heptanone reduced the responsivity of the VTA-nucleus accumbens shell but did not influence the responsivity of the VTA-nucleus accumbens core. The lower VTA-nucleus accumbens shell excitability may be related to a primary defensive warning when exposed to an alarm pheromone. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. Agmatine in the hypothalamic paraventricular nucleus stimulates feeding in rats: involvement of neuropeptide Y

    PubMed Central

    Taksande, BG; Kotagale, NR; Nakhate, KT; Mali, PD; Kokare, DM; Hirani, K; Subhedar, NK; Chopde, CT; Ugale, RR

    2011-01-01

    BACKGROUND AND PURPOSE Agmatine, a multifaceted neurotransmitter, is abundantly expressed in the hypothalamic paraventricular nucleus (PVN). Our aim was to assess (i) the effect of agmatine on feeding behaviour and (ii) its association, if any, with neuropeptide Y (NPY). EXPERIMENTAL APPROACH Satiated rats fitted with intra-PVN cannulae were administered agmatine, alone or jointly with (i) α2-adrenoceptor agonist, clonidine, or antagonist, yohimbine; (ii) NPY, NPY Y1 receptor agonist, [Leu31, Pro34]-NPY, or antagonist, BIBP3226; or (iii) yohimbine and NPY. Cumulative food intake was monitored at different post-injection time points. Furthermore, the expression of hypothalamic NPY following i.p. treatment with agmatine, alone or in combination with yohimbine (i.p.), was evaluated by immunocytochemistry. KEY RESULTS Agmatine robustly increased feeding in a dose-dependent manner. While pretreatment with clonidine augmented, yohimbine attenuated the orexigenic response to agmatine. Similarly, NPY and [Leu31, Pro34]-NPY potentiated the agmatine-induced hyperphagia, whereas BIBP3226 inhibited it. Moreover, yohimbine attenuated the synergistic orexigenic effect induced by the combination of NPY and agmatine. Agmatine increased NPY immunoreactivity in the PVN fibres and in the cells of the hypothalamic arcuate nucleus (ARC) and this effect was prevented by pretreatment with yohimbine. NPY immunoreactivity in the fibres of the ARC, dorsomedial, ventromedial and lateral nuclei of the hypothalamus was not affected by any of the above treatments. CONCLUSIONS AND IMPLICATIONS The orexigenic effect of agmatine is coupled to increased NPY activity mediated by stimulation of α2-adrenoceptors within the PVN. This signifies the importance of agmatine or α2-adrenoceptor modulators in the development of novel therapeutic agents to treat feeding-related disorders. PMID:21564088

  7. Stimulation of the subthalamic nucleus and impulsivity: release your horses.

    PubMed

    Ballanger, Benedicte; van Eimeren, Thilo; Moro, Elena; Lozano, Andres M; Hamani, Clement; Boulinguez, Philippe; Pellecchia, Giovanna; Houle, Sylvain; Poon, Yu Yan; Lang, Anthony E; Strafella, Antonio P

    2009-12-01

    In Parkinson disease (PD) patients, deep brain stimulation (DBS) of the subthalamic nucleus (STN) may contribute to certain impulsive behavior during high-conflict decisions. A neurocomputational model of the basal ganglia has recently been proposed that suggests this behavioral aspect may be related to the role played by the STN in relaying a "hold your horses" signal intended to allow more time to settle on the best option. The aim of the present study was 2-fold: 1) to extend these observations by providing evidence that the STN may influence and prevent the execution of any response even during low-conflict decisions; and 2) to identify the neural correlates of this effect. We measured regional cerebral blood flow during a Go/NoGo and a control (Go) task to study the motor improvement and response inhibition deficits associated with STN-DBS in patients with PD. Although it improved Unified Parkinson Disease Rating Scale motor ratings and induced a global decrease in reaction time during task performance, STN-DBS impaired response inhibition, as revealed by an increase in commission errors in NoGo trials. These behavioral effects were accompanied by changes in synaptic activity consisting of a reduced activation in the cortical networks responsible for reactive and proactive response inhibition. The present results suggest that although it improves motor functions in PD patients, modulation of STN hyperactivity with DBS may tend at the same time to favor the appearance of impulsive behavior by acting on the gating mechanism involved in response initiation.

  8. Distinct roles of dopamine and subthalamic nucleus in learning and probabilistic decision making.

    PubMed

    Coulthard, Elizabeth J; Bogacz, Rafal; Javed, Shazia; Mooney, Lucy K; Murphy, Gillian; Keeley, Sophie; Whone, Alan L

    2012-12-01

    Even simple behaviour requires us to make decisions based on combining multiple pieces of learned and new information. Making such decisions requires both learning the optimal response to each given stimulus as well as combining probabilistic information from multiple stimuli before selecting a response. Computational theories of decision making predict that learning individual stimulus-response associations and rapid combination of information from multiple stimuli are dependent on different components of basal ganglia circuitry. In particular, learning and retention of memory, required for optimal response choice, are significantly reliant on dopamine, whereas integrating information probabilistically is critically dependent upon functioning of the glutamatergic subthalamic nucleus (computing the 'normalization term' in Bayes' theorem). Here, we test these theories by investigating 22 patients with Parkinson's disease either treated with deep brain stimulation to the subthalamic nucleus and dopaminergic therapy or managed with dopaminergic therapy alone. We use computerized tasks that probe three cognitive functions-information acquisition (learning), memory over a delay and information integration when multiple pieces of sequentially presented information have to be combined. Patients performed the tasks ON or OFF deep brain stimulation and/or ON or OFF dopaminergic therapy. Consistent with the computational theories, we show that stopping dopaminergic therapy impairs memory for probabilistic information over a delay, whereas deep brain stimulation to the region of the subthalamic nucleus disrupts decision making when multiple pieces of acquired information must be combined. Furthermore, we found that when participants needed to update their decision on the basis of the last piece of information presented in the decision-making task, patients with deep brain stimulation of the subthalamic nucleus region did not slow down appropriately to revise their plan, a

  9. Deep brain stimulation of the rostromedial tegmental nucleus: An unanticipated, selective effect on food intake.

    PubMed

    Melse, Maartje; Temel, Yasin; Tan, Sonny K; Jahanshahi, Ali

    2016-10-01

    The rostromedial tegmental nucleus (RMTg) is a relatively newly described brainstem structure. The RMTg is extensively connected to both dopaminergic (DA) and serotoninergic key areas and it fulfills a pivotal role in the regulation of mesolimbic and nigrostriatal DA release. The RMTg may directly influence DA- and 5-HT associated motor and possibly also mood related behavior, the latter of which has not yet been well described. The current study explored the consequences of RMTg manipulation on DA- and 5-HT related behavior through the application of RMTg deep brain stimulation (DBS) with both high and low frequency stimulation (LFS and HFS). We used a wide array of motor and mood tests to assess changes in behavior. RMTg DBS did not change behavioral outcomes in the Skinner box task, nor in the Catwalk, the sucrose intake test, the open field test, the elevated zero maze, or the place preference test, but LFS did induce a significant decrease in food intake. This seems to be a selective effect as no motor or anxiety changes were observed that could lead to attenuated food intake. This finding not only underlines the RMTg's braking effect on the VTA, but possibly also on the forebrain, where GABA-ergic RMTg efferent may cause suppression of feeding in the lateral hypothalamus. Copyright © 2016. Published by Elsevier Inc.

  10. Closing the loop of deep brain stimulation

    PubMed Central

    Carron, Romain; Chaillet, Antoine; Filipchuk, Anton; Pasillas-Lépine, William; Hammond, Constance

    2013-01-01

    High-frequency deep brain stimulation is used to treat a wide range of brain disorders, like Parkinson's disease. The stimulated networks usually share common electrophysiological signatures, including hyperactivity and/or dysrhythmia. From a clinical perspective, HFS is expected to alleviate clinical signs without generating adverse effects. Here, we consider whether the classical open-loop HFS fulfills these criteria and outline current experimental or theoretical research on the different types of closed-loop DBS that could provide better clinical outcomes. In the first part of the review, the two routes followed by HFS-evoked axonal spikes are explored. In one direction, orthodromic spikes functionally de-afferent the stimulated nucleus from its downstream target networks. In the opposite direction, antidromic spikes prevent this nucleus from being influenced by its afferent networks. As a result, the pathological synchronized activity no longer propagates from the cortical networks to the stimulated nucleus. The overall result can be described as a reversible functional de-afferentation of the stimulated nucleus from its upstream and downstream nuclei. In the second part of the review, the latest advances in closed-loop DBS are considered. Some of the proposed approaches are based on mathematical models, which emphasize different aspects of the parkinsonian basal ganglia: excessive synchronization, abnormal firing-rate rhythms, and a deficient thalamo-cortical relay. The stimulation strategies are classified depending on the control-theory techniques on which they are based: adaptive and on-demand stimulation schemes, delayed and multi-site approaches, stimulations based on proportional and/or derivative control actions, optimal control strategies. Some of these strategies have been validated experimentally, but there is still a large reservoir of theoretical work that may point to ways of improving practical treatment. PMID:24391555

  11. Closing the loop of deep brain stimulation.

    PubMed

    Carron, Romain; Chaillet, Antoine; Filipchuk, Anton; Pasillas-Lépine, William; Hammond, Constance

    2013-12-20

    High-frequency deep brain stimulation is used to treat a wide range of brain disorders, like Parkinson's disease. The stimulated networks usually share common electrophysiological signatures, including hyperactivity and/or dysrhythmia. From a clinical perspective, HFS is expected to alleviate clinical signs without generating adverse effects. Here, we consider whether the classical open-loop HFS fulfills these criteria and outline current experimental or theoretical research on the different types of closed-loop DBS that could provide better clinical outcomes. In the first part of the review, the two routes followed by HFS-evoked axonal spikes are explored. In one direction, orthodromic spikes functionally de-afferent the stimulated nucleus from its downstream target networks. In the opposite direction, antidromic spikes prevent this nucleus from being influenced by its afferent networks. As a result, the pathological synchronized activity no longer propagates from the cortical networks to the stimulated nucleus. The overall result can be described as a reversible functional de-afferentation of the stimulated nucleus from its upstream and downstream nuclei. In the second part of the review, the latest advances in closed-loop DBS are considered. Some of the proposed approaches are based on mathematical models, which emphasize different aspects of the parkinsonian basal ganglia: excessive synchronization, abnormal firing-rate rhythms, and a deficient thalamo-cortical relay. The stimulation strategies are classified depending on the control-theory techniques on which they are based: adaptive and on-demand stimulation schemes, delayed and multi-site approaches, stimulations based on proportional and/or derivative control actions, optimal control strategies. Some of these strategies have been validated experimentally, but there is still a large reservoir of theoretical work that may point to ways of improving practical treatment.

  12. Selective optogenetic stimulation of the retrotrapezoid nucleus in sleeping rats activates breathing without changing blood pressure or causing arousal or sighs

    PubMed Central

    Burke, Peter G. R.; Kanbar, Roy; Viar, Kenneth E.; Stornetta, Ruth L.

    2015-01-01

    Combined optogenetic activation of the retrotrapezoid nucleus (RTN; a CO2/proton-activated brainstem nucleus) with nearby catecholaminergic neurons (C1 and A5), or selective C1 neuron stimulation, increases blood pressure (BP) and breathing, causes arousal from non-rapid eye movement (non-REM) sleep, and triggers sighs. Here we wished to determine which of these physiological responses are elicited when RTN neurons are selectively activated. The left rostral RTN and nearby A5 neurons were transduced with channelrhodopsin-2 (ChR2+) using a lentiviral vector. Very few C1 cells were transduced. BP, breathing, EEG, and neck EMG were monitored. During non-REM sleep, photostimulation of ChR2+ neurons (20s, 2-20 Hz) instantly increased V̇e without changing BP (13 rats). V̇e and BP were unaffected by light in nine control (ChR2−) rats. Photostimulation produced no sighs and caused arousal (EEG desynchronization) more frequently in ChR2+ than ChR2− rats (62 ± 5% of trials vs. 25 ± 2%; P < 0.0001). Six ChR2+ rats then received spinal injections of a saporin-based toxin that spared RTN neurons but destroyed surrounding catecholaminergic neurons. Photostimulation of the ChR2+ neurons produced the same ventilatory stimulation before and after lesion, but arousal was no longer elicited. Overall (all ChR2+ rats combined), ΔV̇e correlated with the number of ChR2+ RTN neurons whereas arousal probability correlated with the number of ChR2+ catecholaminergic neurons. In conclusion, RTN neurons activate breathing powerfully and, unlike the C1 cells, have minimal effects on BP and have a weak arousal capability at best. A5 neuron stimulation produces little effect on breathing and BP but does appear to facilitate arousal. PMID:25858492

  13. Advanced MR Imaging of the Human Nucleus Accumbens--Additional Guiding Tool for Deep Brain Stimulation.

    PubMed

    Lucas-Neto, Lia; Reimão, Sofia; Oliveira, Edson; Rainha-Campos, Alexandre; Sousa, João; Nunes, Rita G; Gonçalves-Ferreira, António; Campos, Jorge G

    2015-07-01

    The human nucleus accumbens (Acc) has become a target for deep brain stimulation (DBS) in some neuropsychiatric disorders. Nonetheless, even with the most recent advances in neuroimaging it remains difficult to accurately delineate the Acc and closely related subcortical structures, by conventional MRI sequences. It is our purpose to perform a MRI study of the human Acc and to determine whether there are reliable anatomical landmarks that enable the precise location and identification of the nucleus and its core/shell division. For the Acc identification and delineation, based on anatomical landmarks, T1WI, T1IR and STIR 3T-MR images were acquired in 10 healthy volunteers. Additionally, 32-direction DTI was obtained for Acc segmentation. Seed masks for the Acc were generated with FreeSurfer and probabilistic tractography was performed using FSL. The probability of connectivity between the seed voxels and distinct brain areas was determined and subjected to k-means clustering analysis, defining 2 different regions. With conventional T1WI, the Acc borders are better defined through its surrounding anatomical structures. The DTI color-coded vector maps and IR sequences add further detail in the Acc identification and delineation. Additionally, using probabilistic tractography it is possible to segment the Acc into a core and shell division and establish its structural connectivity with different brain areas. Advanced MRI techniques allow in vivo delineation and segmentation of the human Acc and represent an additional guiding tool in the precise and safe target definition for DBS. © 2015 International Neuromodulation Society.

  14. Reorganization of the raccoon cuneate nucleus after peripheral denervation.

    PubMed

    Rasmusson, D D; Northgrave, S A

    1997-12-01

    The effects of peripheral nerve transection on the cuneate nucleus were studied in anesthetized raccoons using extracellular, single-unit recordings. The somatotopic organization of the cuneate nucleus first was examined in intact, control animals. The cuneate nucleus in the raccoon is organized with the digits represented in separate cell clusters. The dorsal cap region of the cuneate nucleus contains a representation of the claws and hairy skin of the digits. Within the representation of the glabrous skin, neurons with rapidly adapting properties tended to be segregated from those with slowly adapting properties. The representations of the distal and proximal pads on a digit also were segregated. Electrical stimulation of two adjacent digits provided a detailed description of the responses originating from the digit that contains the tactile receptive field (the on-focus digit) and from the adjacent (off-focus) digit. Stimulation of the on-focus digit produced a short latency excitation in all 99 neurons tested, with a mean of 10.5 ms. These responses had a low threshold (426 microA). Stimulation of an off-focus digit activated 65% of these neurons. These responses had a significantly longer latency (15.3 ms) than on-focus responses and the threshold was more than twice as large. Two to five months after amputation of digit 4, 97 cells were tested with stimulation of digits 3 and 5. A total of 44 were in the intact regions of the cuneate nucleus. They had small receptive fields on intact digits and their responses to electrical stimulation did not differ from the control neurons. The remaining 53 neurons were judged to be deafferented and in the fourth digit region on the basis of their location with respect to intact neurons. All but two of these cells had receptive fields that were much larger than normal, often including more than one digit and part of the palm. When compared with the off-focus control neurons, their responses to electrical stimulation had

  15. Effect of subthalamic nucleus deep brain stimulation on dual-task cognitive and motor performance in isolated dystonia

    PubMed Central

    Mills, Kelly A; Markun, Leslie C; Luciano, Marta San; Rizk, Rami; Allen, I Elaine; Racine, Caroline A; Starr, Philip A; Alberts, Jay L; Ostrem, Jill L

    2015-01-01

    Objective Subthalamic nucleus (STN) deep brain stimulation (DBS) can improve motor complications of Parkinson's disease (PD) but may worsen specific cognitive functions. The effect of STN DBS on cognitive function in dystonia patients is less clear. Previous reports indicate that bilateral STN stimulation in patients with PD amplifies the decrement in cognitive-motor dual-task performance seen when moving from a single-task to dual-task paradigm. We aimed to determine if the effect of bilateral STN DBS on dual-task performance in isolated patients with dystonia, who have less cognitive impairment and no dementia, is similar to that seen in PD. Methods Eight isolated predominantly cervical patients with dystonia treated with bilateral STN DBS, with average dystonia duration of 10.5 years and Montreal Cognitive Assessment score of 26.5, completed working memory (n-back) and motor (forced-maintenance) tests under single-task and dual-task conditions while on and off DBS. Results A multivariate, repeated-measures analysis of variance showed no effect of stimulation status (On vs Off) on working memory (F=0.75, p=0.39) or motor function (F=0.22, p=0.69) when performed under single-task conditions, though as working memory task difficulty increased, stimulation disrupted the accuracy of force-tracking. There was a very small worsening in working memory performance (F=9.14, p=0.019) when moving from single-task to dual-tasks when using the ‘dual-task loss’ analysis. Conclusions This study suggests the effect of STN DBS on working memory and attention may be much less consequential in patients with dystonia than has been reported in PD. PMID:25012202

  16. Inhibition of 5-HT neuron activity and induction of depressive-like behavior by high-frequency stimulation of the subthalamic nucleus.

    PubMed

    Temel, Yasin; Boothman, Laura J; Blokland, Arjan; Magill, Peter J; Steinbusch, Harry W M; Visser-Vandewalle, Veerle; Sharp, Trevor

    2007-10-23

    Bilateral, high-frequency stimulation (HFS) of the subthalamic nucleus (STN) is the surgical therapy of choice for movement disability in advanced Parkinson's disease (PD), but this procedure evokes debilitating psychiatric effects, including depressed mood, of unknown neural origin. Here, we report the unexpected finding that HFS of the STN inhibits midbrain 5-hydroxytryptamine (5-HT) neurons to evoke depression-related behavioral changes. We found that bilateral HFS of the STN consistently inhibited (40-50%) the firing rate of 5-HT neurons in the dorsal raphe nucleus of the rat, but not neighboring non-5-HT neurons. This effect was apparent at clinically relevant stimulation parameters (> or =100 Hz, > or =30 microA), was not elicited by HFS of either neighboring or remote structures to the STN, and was still present in rat models of PD. We also found that bilateral HFS of the STN evoked clear-cut, depressive-like behavior in a widely used experimental paradigm of depression (forced swim test), and this effect was also observed in a PD model. Importantly, the depressive-like behavior elicited by HFS of the STN was reversed by a selective 5-HT-enhancing antidepressant, thereby linking the behavioral change to decreased 5-HT neuronal activity. Overall, these findings link reduced 5-HT function to the psychiatric effects of HFS of the STN observed in PD patients and provide a rational basis for their clinical management. More generally, the powerful interaction between the STN and 5-HT system uncovered here offers insights into the high level of comorbidity of basal ganglia disease and mood disorder.

  17. Ventral tegmental ionotropic glutamate receptor stimulation of nucleus accumbens tonic dopamine efflux blunts hindbrain-evoked phasic neurotransmission: implications for dopamine dysregulation disorders.

    PubMed

    Tye, S J; Miller, A D; Blaha, C D

    2013-11-12

    Activation of glutamate receptors within the ventral tegmental area (VTA) stimulates extrasynaptic (basal) dopamine release in terminal regions, including the nucleus accumbens (NAc). Hindbrain inputs from the laterodorsal tegmental nucleus (LDT) are critical for elicitation of phasic VTA dopamine cell activity and consequent transient dopamine release. This study investigated the role of VTA ionotropic glutamate receptor (iGluR) stimulation on both basal and LDT electrical stimulation-evoked dopamine efflux in the NAc using in vivo chronoamperometry and fixed potential amperometry in combination with stearate-graphite paste and carbon fiber electrodes, respectively. Intra-VTA infusion of the iGluR agonists (±)-α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA; 1 μg/μl) or N-methyl-d-aspartic acid (NMDA; 2 μg/μl) enhanced basal NAc dopamine efflux. This iGluR-mediated potentiation of basal dopamine efflux was paralleled by an attenuation of LDT-evoked transient NAc dopamine efflux, suggesting that excitation of basal activity effectively inhibited the capacity of hindbrain afferents to elicit transient dopamine efflux. In line with this, post-NMDA infusion of the dopamine D2 autoreceptor (D2R) agonist quinpirole (1 μg/μl; intra-VTA) partially recovered NMDA-mediated attenuation of LDT-evoked NAc dopamine, while concurrently attenuating NMDA-mediated potentiation of basal dopamine efflux. Post-NMDA infusion of quinpirole (1 μg/μl) alone attenuated basal and LDT-evoked dopamine efflux. Taken together, these data reveal that hyperstimulation of basal dopamine transmission can stunt hindbrain burst-like stimulation-evoked dopamine efflux. Inhibitory autoreceptor mechanisms within the VTA help to partially recover the magnitude of phasic dopamine efflux, highlighting the importance of both iGluRs and D2 autoreceptors in maintaining the functional balance of tonic and phasic dopamine neurotransmission. Dysregulation of this balance may have important

  18. Comparison of magnetic resonance imaging sequences for depicting the subthalamic nucleus for deep brain stimulation.

    PubMed

    Nagahama, Hiroshi; Suzuki, Kengo; Shonai, Takaharu; Aratani, Kazuki; Sakurai, Yuuki; Nakamura, Manami; Sakata, Motomichi

    2015-01-01

    Electrodes are surgically implanted into the subthalamic nucleus (STN) of Parkinson's disease patients to provide deep brain stimulation. For ensuring correct positioning, the anatomic location of the STN must be determined preoperatively. Magnetic resonance imaging has been used for pinpointing the location of the STN. To identify the optimal imaging sequence for identifying the STN, we compared images produced with T2 star-weighted angiography (SWAN), gradient echo T2*-weighted imaging, and fast spin echo T2-weighted imaging in 6 healthy volunteers. Our comparison involved measurement of the contrast-to-noise ratio (CNR) for the STN and substantia nigra and a radiologist's interpretations of the images. Of the sequences examined, the CNR and qualitative scores were significantly higher on SWAN images than on other images (p < 0.01) for STN visualization. Kappa value (0.74) on SWAN images was the highest in three sequences for visualizing the STN. SWAN is the sequence best suited for identifying the STN at the present time.

  19. Speech outcomes in Parkinson's disease after subthalamic nucleus deep brain stimulation: A systematic review.

    PubMed

    Aldridge, Danielle; Theodoros, Deborah; Angwin, Anthony; Vogel, Adam P

    2016-12-01

    Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is effective in reducing motor symptoms for many individuals with Parkinson's disease (PD). However, STN DBS does not appear to influence speech in the same way, and may result in a variety of negative outcomes for people with PD (PWP). A high degree of inter-individual variability amongst PWP regarding speech outcomes following STN DBS is evident in many studies. Furthermore, speech studies in PWP following STN DBS have employed a wide variety of designs and methodologies, which complicate comparison and interpretation of outcome data amongst studies within this growing body of research. An analysis of published evidence regarding speech outcomes in PWP following STN DBS, according to design and quality, is missing. This systematic review aimed to analyse and coalesce all of the current evidence reported within observational and experimental studies investigating the effects of STN DBS on speech. It will strengthen understanding of the relationship between STN DBS and speech, and inform future research by highlighting methodological limitations of current evidence. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Nucleus Accumbens Deep Brain Stimulation in Patients with Substance Use Disorders and Delay Discounting.

    PubMed

    Peisker, Canan B; Schüller, Thomas; Peters, Jan; Wagner, Ben J; Schilbach, Leonhard; Müller, Ulf J; Visser-Vandewalle, Veerle; Kuhn, Jens

    2018-01-27

    Deep brain stimulation (DBS) of the nucleus accumbens (NAc) shows first promising results in patients with severe substance use disorder (SUD), a patient group known to have deficits in self-control. One facet of self-control is the ability to forego smaller sooner rewards in favor of larger later rewards (delay discounting, DD). The NAc has been suggested to integrate motivational information to guide behavior while the consequences of NAc-DBS on DD are unknown. To this end, nine patients with SUD performed a DD task with DBS on and after a 24 h DBS off period. Furthermore, 18 healthy controls were measured to assess possible alterations in DD in patients with SUD. Our findings implicate that DD was not significantly modulated by NAc-DBS and also that patients with SUD did not differ from healthy controls. While null results must be interpreted with caution, the commonly observed association of impaired DD in SUD might suggest a long-term effect of NAc-DBS that was not sufficiently modulated by a 24 h DBS off period.

  1. Momentum loss in proton-nucleus and nucleus-nucleus collisions

    NASA Technical Reports Server (NTRS)

    Khan, Ferdous; Townsend, Lawrence W.

    1993-01-01

    An optical model description, based on multiple scattering theory, of longitudinal momentum loss in proton-nucleus and nucleus-nucleus collisions is presented. The crucial role of the imaginary component of the nucleon-nucleon transition matrix in accounting for longitudinal momentum transfer is demonstrated. Results obtained with this model are compared with Intranuclear Cascade (INC) calculations, as well as with predictions from Vlasov-Uehling-Uhlenbeck (VUU) and quantum molecular dynamics (QMD) simulations. Comparisons are also made with experimental data where available. These indicate that the present model is adequate to account for longitudinal momentum transfer in both proton-nucleus and nucleus-nucleus collisions over a wide range of energies.

  2. Non-stationary discharge patterns in motor cortex under subthalamic nucleus deep brain stimulation.

    PubMed

    Santaniello, Sabato; Montgomery, Erwin B; Gale, John T; Sarma, Sridevi V

    2012-01-01

    Deep brain stimulation (DBS) of the subthalamic nucleus (STN) directly modulates the basal ganglia (BG), but how such stimulation impacts the cortex upstream is largely unknown. There is evidence of cortical activation in 6-hydroxydopamine (OHDA)-lesioned rodents and facilitation of motor evoked potentials in Parkinson's disease (PD) patients, but the impact of the DBS settings on the cortical activity in normal vs. Parkinsonian conditions is still debated. We use point process models to analyze non-stationary activation patterns and inter-neuronal dependencies in the motor and sensory cortices of two non-human primates during STN DBS. These features are enhanced after treatment with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), which causes a consistent PD-like motor impairment, while high-frequency (HF) DBS (i.e., ≥100 Hz) strongly reduces the short-term patterns (period: 3-7 ms) both before and after MPTP treatment, and elicits a short-latency post-stimulus activation. Low-frequency DBS (i.e., ≤50 Hz), instead, has negligible effects on the non-stationary features. Finally, by using tools from the information theory [i.e., receiver operating characteristic (ROC) curve and information rate (IR)], we show that the predictive power of these models is dependent on the DBS settings, i.e., the probability of spiking of the cortical neurons (which is captured by the point process models) is significantly conditioned on the timely delivery of the DBS input. This dependency increases with the DBS frequency and is significantly larger for high- vs. low-frequency DBS. Overall, the selective suppression of non-stationary features and the increased modulation of the spike probability suggest that HF STN DBS enhances the neuronal activation in motor and sensory cortices, presumably because of reinforcement mechanisms, which perhaps involve the overlap between feedback antidromic and feed-forward orthodromic responses along the BG-thalamo-cortical loop.

  3. Effect of subthalamic nucleus deep brain stimulation on dual-task cognitive and motor performance in isolated dystonia.

    PubMed

    Mills, Kelly A; Markun, Leslie C; San Luciano, Marta; Rizk, Rami; Allen, I Elaine; Racine, Caroline A; Starr, Philip A; Alberts, Jay L; Ostrem, Jill L

    2015-04-01

    Subthalamic nucleus (STN) deep brain stimulation (DBS) can improve motor complications of Parkinson's disease (PD) but may worsen specific cognitive functions. The effect of STN DBS on cognitive function in dystonia patients is less clear. Previous reports indicate that bilateral STN stimulation in patients with PD amplifies the decrement in cognitive-motor dual-task performance seen when moving from a single-task to dual-task paradigm. We aimed to determine if the effect of bilateral STN DBS on dual-task performance in isolated patients with dystonia, who have less cognitive impairment and no dementia, is similar to that seen in PD. Eight isolated predominantly cervical patients with dystonia treated with bilateral STN DBS, with average dystonia duration of 10.5 years and Montreal Cognitive Assessment score of 26.5, completed working memory (n-back) and motor (forced-maintenance) tests under single-task and dual-task conditions while on and off DBS. A multivariate, repeated-measures analysis of variance showed no effect of stimulation status (On vs Off) on working memory (F=0.75, p=0.39) or motor function (F=0.22, p=0.69) when performed under single-task conditions, though as working memory task difficulty increased, stimulation disrupted the accuracy of force-tracking. There was a very small worsening in working memory performance (F=9.14, p=0.019) when moving from single-task to dual-tasks when using the 'dual-task loss' analysis. This study suggests the effect of STN DBS on working memory and attention may be much less consequential in patients with dystonia than has been reported in PD. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  4. Interleaving subthalamic nucleus deep brain stimulation to avoid side effects while achieving satisfactory motor benefits in Parkinson disease: A report of 12 cases.

    PubMed

    Zhang, Shizhen; Zhou, Peizhi; Jiang, Shu; Wang, Wei; Li, Peng

    2016-12-01

    Deep brain stimulation (DBS) of the subthalamic nucleus is an effective treatment for advanced Parkinson disease (PD). However, achieving ideal outcomes by conventional programming can be difficult in some patients, resulting in suboptimal control of PD symptoms and stimulation-induced adverse effects. Interleaving stimulation (ILS) is a newer programming technique that can individually optimize the stimulation area, thereby improving control of PD symptoms while alleviating stimulation-induced side effects after conventional programming fails to achieve the desired results. We retrospectively reviewed PD patients who received DBS programming during the previous 4 years in our hospital. We collected clinical and demographic data from 12 patients who received ILS because of incomplete alleviation of PD symptoms or stimulation-induced adverse effects after conventional programming had proven ineffective or intolerable. Appropriate lead location was confirmed with postoperative reconstruction images. The rationale and clinical efficacy of ILS was analyzed. We divided our patients into 4 groups based on the following symptoms: stimulation-induced dysarthria and choreoathetoid dyskinesias, gait disturbance, and incomplete control of parkinsonism. After treatment with ILS, patients showed satisfactory improvement in PD symptoms and alleviation of stimulation-induced side effects, with a mean improvement in Unified PD Rating Scale motor scores of 26.9%. ILS is a newer choice and effective programming strategy to maximize symptom control in PD while decreasing stimulation-induced adverse effects when conventional programming fails to achieve satisfactory outcome. However, we should keep in mind that most DBS patients are routinely treated with conventional stimulation and that not all patients benefit from ILS. ILS is not recommended as the first choice of programming, and it is recommended only when patients have unsatisfactory control of PD symptoms or stimulation

  5. Complex repetitive behavior: punding after bilateral subthalamic nucleus stimulation in Parkinson's disease.

    PubMed

    Pallanti, Stefano; Bernardi, Silvia; Raglione, Laura Maria; Marini, Paolo; Ammannati, Franco; Sorbi, Sandro; Ramat, Silvia

    2010-07-01

    "Punding" is the term used to describe a stereotyped motor behavior characterized by an intense fascination with repetitive purposeless movements, such as taking apart mechanical objects, handling common objects as if they were new and entertaining, constantly picking at oneself, etc. As a phenomenon with both impulsive and compulsive features, the phenomenology of punding is currently being questioned. In order to investigate the pathophysiology of this phenomenon, we screened a population of Parkinson's disease (PD) outpatients who underwent subthalamic nucleus deep brain stimulation (STN DBS). We conducted a patient-and-relative-completed survey with 24 consecutive patients in an academic outpatient care center, using a modified version of a structured interview. Patients were administered the Unified Parkinson's Disease Rating Scale (UPDRS), the Obsessive-Compulsive Inventory and the Sheehan Disability Scale. Five (20.8%) of the 24 subjects were identified as punders, including three men (60%) and two women. The punders were comparable to the non-punders in terms of clinical and demographic factors. The punder and non-punder groups only differed statistically with regard to the length of time from DBS implantation. Those findings suggest that punding might be induced by STN DBS, and its rate of occurrence in DBS population seems to be more common than previously suspected. Copyright 2010 Elsevier Ltd. All rights reserved.

  6. Postmortem volumetric analysis of the nucleus accumbens in male heroin addicts: implications for deep brain stimulation.

    PubMed

    Müller, Ulf J; Truebner, Kurt; Schiltz, Kolja; Kuhn, Jens; Mawrin, Christian; Dobrowolny, Henrik; Bernstein, Hans-Gert; Bogerts, Bernhard; Steiner, Johann

    2015-12-01

    Deep brain stimulation (DBS) of the nucleus accumbens (NAc) is increasingly investigated in neuropsychiatric disorders. DBS requires computer-assisted 3D planning to implant the stimulation electrode precisely. Recently, there has been a debate about the true dimensions of NAc in healthy as well as in mentally ill individuals. Knowing its true dimensions in different neuropsychiatric disorders may improve even more precise targeting of NAc for therapeutic DBS. Volumes of NAc of heroin addicts (n = 14) and healthy controls (n = 12) were calculated by using morphometry of serial whole-brain sections. Total brain volume was larger in the heroin group (mean 1478.85 ± 62.34 vs. mean 1352.38 ± 103.24 cm(3)), as the heroin group was more than 10 years younger (p = 0.001). However, the mean volume of the NAc in heroin addicts was smaller than in controls (0.528 ± 0.166 vs. 0.623 ± 0.196 cm(3); p = 0.019). This group effect did not significantly differ between the hemispheres. When assessed separately, left-hemispheric NAc volume was 15 % lower (p = 0.020), while right-hemispheric NAc volume was 16 % lower (p = 0.047) in the heroin-addicted group compared to controls. Based on these diagnosis-related differences, we believe it is important to further analyze NAc volumes in different psychiatric disorders to further improve precise targeting and electrode placement.

  7. BOLD temporal dynamics of rat superior colliculus and lateral geniculate nucleus following short duration visual stimulation.

    PubMed

    Lau, Condon; Zhou, Iris Y; Cheung, Matthew M; Chan, Kevin C; Wu, Ed X

    2011-04-29

    The superior colliculus (SC) and lateral geniculate nucleus (LGN) are important subcortical structures for vision. Much of our understanding of vision was obtained using invasive and small field of view (FOV) techniques. In this study, we use non-invasive, large FOV blood oxygenation level-dependent (BOLD) fMRI to measure the SC and LGN's response temporal dynamics following short duration (1 s) visual stimulation. Experiments are performed at 7 tesla on Sprague Dawley rats stimulated in one eye with flashing light. Gradient-echo and spin-echo sequences are used to provide complementary information. An anatomical image is acquired from one rat after injection of monocrystalline iron oxide nanoparticles (MION), a blood vessel contrast agent. BOLD responses are concentrated in the contralateral SC and LGN. The SC BOLD signal measured with gradient-echo rises to 50% of maximum amplitude (PEAK) 0.2±0.2 s before the LGN signal (p<0.05). The LGN signal returns to 50% of PEAK 1.4±1.2 s before the SC signal (p<0.05). These results indicate the SC signal rises faster than the LGN signal but settles slower. Spin-echo results support these findings. The post-MION image shows the SC and LGN lie beneath large blood vessels. This subcortical vasculature is similar to that in the cortex, which also lies beneath large vessels. The LGN lies closer to the large vessels than much of the SC. The differences in response timing between SC and LGN are very similar to those between deep and shallow cortical layers following electrical stimulation, which are related to depth-dependent blood vessel dilation rates. This combined with the similarities in vasculature between subcortex and cortex suggest the SC and LGN timing differences are also related to depth-dependent dilation rates. This study shows for the first time that BOLD responses in the rat SC and LGN following short duration visual stimulation are temporally different.

  8. Electrophysiological and morphological properties of neurons in the prepositus hypoglossi nucleus that express both ChAT and VGAT in a double-transgenic rat model.

    PubMed

    Saito, Yasuhiko; Zhang, Yue; Yanagawa, Yuchio

    2015-04-01

    Although it has been proposed that neurons that contain both acetylcholine (ACh) and γ-aminobutyric acid (GABA) are present in the prepositus hypoglossi nucleus (PHN), these neurons have not been characterized because of the difficulty in identifying them. In the present study, PHN neurons that express both choline acetyltransferase and the vesicular GABA transporter (VGAT) were identified using double-transgenic rats, in which the cholinergic and inhibitory neurons express the fluorescent proteins tdTomato and Venus, respectively. To characterize the neurons that express both tdTomato and Venus (D+ neurons), the afterhyperpolarization (AHP) profiles and firing patterns of these neurons were investigated via whole-cell recordings of brainstem slice preparations. Regarding the three AHP profiles and four firing patterns that the D+ neurons exhibited, an AHP with an afterdepolarization and a firing pattern that exhibited a delay in the generation of the first spike were the preferential properties of these neurons. In the three morphological types classified, the multipolar type that exhibited radiating dendrites was predominant among the D+ neurons. Immunocytochemical analysis revealed that the VGAT-immunopositive axonal boutons that expressed tdTomato were primarily located in the dorsal cap of inferior olive (IO) and the PHN. Although the PHN receives cholinergic inputs from the pedunculopontine tegmental nucleus and laterodorsal tegmental nucleus, D+ neurons were absent from these brain areas. Together, these results suggest that PHN neurons that co-express ACh and GABA exhibit specific electrophysiological and morphological properties, and innervate the dorsal cap of the IO and the PHN. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  9. Pilot study assessing the feasibility of applying bilateral subthalamic nucleus deep brain stimulation in very early stage Parkinson's disease: study design and rationale.

    PubMed

    Charles, David; Tolleson, Christopher; Davis, Thomas L; Gill, Chandler E; Molinari, Anna L; Bliton, Mark J; Tramontana, Michael G; Salomon, Ronald M; Kao, Chris; Wang, Lily; Hedera, Peter; Phibbs, Fenna T; Neimat, Joseph S; Konrad, Peter E

    2012-01-01

    Deep brain stimulation provides significant symptomatic benefit for people with advanced Parkinson's disease whose symptoms are no longer adequately controlled with medication. Preliminary evidence suggests that subthalamic nucleus stimulation may also be efficacious in early Parkinson's disease, and results of animal studies suggest that it may spare dopaminergic neurons in the substantia nigra. We report the methodology and design of a novel Phase I clinical trial testing the safety and tolerability of deep brain stimulation in early Parkinson's disease and discuss previous failed attempts at neuroprotection. We recently conducted a prospective, randomized, parallel-group, single-blind pilot clinical trial of deep brain stimulation in early Parkinson's disease. Subjects were randomized to receive either optimal drug therapy or deep brain stimulation plus optimal drug therapy. Follow-up visits occurred every six months for a period of two years and included week-long therapy washouts. Thirty subjects with Hoehn & Yahr Stage II idiopathic Parkinson's disease were enrolled over a period of 32 months. Twenty-nine subjects completed all follow-up visits; one patient in the optimal drug therapy group withdrew from the study after baseline. Baseline characteristics for all thirty patients were not significantly different. This study demonstrates that it is possible to recruit and retain subjects in a clinical trial testing deep brain stimulation in early Parkinson's disease. The results of this trial will be used to support the design of a Phase III, multicenter trial investigating the efficacy of deep brain stimulation in early Parkinson's disease.

  10. Choreatic Side Effects of Deep Brain Stimulation of the Anteromedial Subthalamic Nucleus for Treatment-Resistant Obsessive-Compulsive disorder.

    PubMed

    Mulders, Anne E P; Leentjens, Albert F G; Schruers, Koen; Duits, Annelien; Ackermans, Linda; Temel, Yasin

    2017-08-01

    Patients with treatment-resistant obsessive-compulsive disorder (OCD) are potential candidates for deep brain stimulation (DBS). The anteromedial subthalamic nucleus (STN) is among the most commonly used targets for DBS in OCD. We present a patient with a 30-year history of treatment-resistant OCD who underwent anteromedial STN-DBS. Despite a clear mood-enhancing effect, stimulation caused motor side effects, including bilateral hyperkinesia, dyskinesias, and sudden large amplitude choreatic movements of arms and legs when stimulating at voltages greater than approximately 1.5 V. DBS at lower amplitudes and at other contact points failed to result in a significant reduction of obsessions and compulsions without inducing motor side effects. Because of this limitation in programming options, we decided to reoperate and target the ventral capsule/ventral striatum (VC/VS), which resulted in a substantial reduction in key obsessive and compulsive symptoms without serious side effects. Choreatic movements and hemiballismus have previously been linked to STN dysfunction and have been incidentally reported as side effects of DBS of the dorsolateral STN in Parkinson disease (PD). However, in PD, these side effects were usually transient, and they rarely interfered with DBS programming. In our patient, the motor side effects were persistent, and they made optimal DBS programming impossible. To our knowledge, such severe and persistent motor side effects have not been described previously for anteromedial STN-DBS. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Subthalamic nucleus deep brain stimulation impacts language in early Parkinson's disease.

    PubMed

    Phillips, Lara; Litcofsky, Kaitlyn A; Pelster, Michael; Gelfand, Matthew; Ullman, Michael T; Charles, P David

    2012-01-01

    Although deep brain stimulation (DBS) of the basal ganglia improves motor outcomes in Parkinson's disease (PD), its effects on cognition, including language, remain unclear. This study examined the impact of subthalamic nucleus (STN) DBS on two fundamental capacities of language, grammatical and lexical functions. These functions were tested with the production of regular and irregular past-tenses, which contrast aspects of grammatical (regulars) and lexical (irregulars) processing while controlling for multiple potentially confounding factors. Aspects of the motor system were tested by contrasting the naming of manipulated (motor) and non-manipulated (non-motor) objects. Performance was compared between healthy controls and early-stage PD patients treated with either DBS/medications or medications alone. Patients were assessed on and off treatment, with controls following a parallel testing schedule. STN-DBS improved naming of manipulated (motor) but not non-manipulated (non-motor) objects, as compared to both controls and patients with just medications, who did not differ from each other across assessment sessions. In contrast, STN-DBS led to worse performance at regulars (grammar) but not irregulars (lexicon), as compared to the other two subject groups, who again did not differ. The results suggest that STN-DBS negatively impacts language in early PD, but may be specific in depressing aspects of grammatical and not lexical processing. The finding that STN-DBS affects both motor and grammar (but not lexical) functions strengthens the view that both depend on basal ganglia circuitry, although the mechanisms for its differential impact on the two (improved motor, impaired grammar) remain to be elucidated.

  12. Subthalamic Nucleus Deep Brain Stimulation Impacts Language in Early Parkinson's Disease

    PubMed Central

    Phillips, Lara; Litcofsky, Kaitlyn A.; Pelster, Michael; Gelfand, Matthew

    2012-01-01

    Although deep brain stimulation (DBS) of the basal ganglia improves motor outcomes in Parkinson's disease (PD), its effects on cognition, including language, remain unclear. This study examined the impact of subthalamic nucleus (STN) DBS on two fundamental capacities of language, grammatical and lexical functions. These functions were tested with the production of regular and irregular past-tenses, which contrast aspects of grammatical (regulars) and lexical (irregulars) processing while controlling for multiple potentially confounding factors. Aspects of the motor system were tested by contrasting the naming of manipulated (motor) and non-manipulated (non-motor) objects. Performance was compared between healthy controls and early-stage PD patients treated with either DBS/medications or medications alone. Patients were assessed on and off treatment, with controls following a parallel testing schedule. STN-DBS improved naming of manipulated (motor) but not non-manipulated (non-motor) objects, as compared to both controls and patients with just medications, who did not differ from each other across assessment sessions. In contrast, STN-DBS led to worse performance at regulars (grammar) but not irregulars (lexicon), as compared to the other two subject groups, who again did not differ. The results suggest that STN-DBS negatively impacts language in early PD, but may be specific in depressing aspects of grammatical and not lexical processing. The finding that STN-DBS affects both motor and grammar (but not lexical) functions strengthens the view that both depend on basal ganglia circuitry, although the mechanisms for its differential impact on the two (improved motor, impaired grammar) remain to be elucidated. PMID:22880117

  13. Effect of beta-phenylethylamine on extracellular concentrations of dopamine in the nucleus accumbens and prefrontal cortex.

    PubMed

    Murata, Mikio; Katagiri, Nobuyuki; Ishida, Kota; Abe, Kenji; Ishikawa, Masago; Utsunomiya, Iku; Hoshi, Keiko; Miyamoto, Ken-ichi; Taguchi, Kyoji

    2009-05-07

    It is known that psychostimulants stimulate dopamine transmission in the nucleus accumbens. In the present study, we examined the effects of systemically administered beta-phenylethylamine (beta-PEA), a psychomotor-stimulating trace amine, on dopamine concentrations in the nucleus accumbens and prefrontal cortex in freely moving rats, using an in vivo microdialysis technique. Intraperitoneal administration of beta-PEA (12.5 and 25 mg/kg) significantly increased extracellular dopamine levels in the nucleus accumbens shell. The observed increase in the dopamine concentration in nucleus accumbens shell dialysate after intraperitoneal administration of 25 mg/kg beta-PEA was inhibited by pre-treatment with a dopamine uptake inhibitor, GBR12909 (10 mg/kg, i.p.). In contrast, beta-PEA (25 mg/kg, i.p.) did not affect dopamine release in the nucleus accumbens core. Although a high dose of beta-PEA (50 mg/kg) significantly increased dopamine levels in the nucleus accumbens core, the dopamine increasing effect of beta-PEA was more potent in the nucleus accumbens shell. Systemic administration of 12.5 and 25 mg/kg beta-PEA also increased extracellular dopamine levels in the prefrontal cortex of rats. However, systemic 25 mg/kg beta-PEA-induced increases in extracellular dopamine levels were not blocked by GBR12909 within the prefrontal cortex. These results suggest that beta-PEA has a greater effect in the shell than in the core and low-dose beta-PEA stimulates dopamine release in the nucleus accumbens shell through uptake by a dopamine transporter. Similarly, beta-PEA increased extracellular dopamine levels in the prefrontal cortex. Thus, beta-PEA may increase extracellular dopamine concentrations in the mesocorticolimbic pathway.

  14. Inhibition of the amygdala central nucleus by stimulation of cerebellar output in rats: a putative mechanism for extinction of the conditioned fear response.

    PubMed

    Magal, Ari; Mintz, Matti

    2014-11-01

    The amygdala and the cerebellum serve two distinctively different functions. The amygdala plays a role in the expression of emotional information, whereas the cerebellum is involved in the timing of discrete motor responses. Interaction between these two systems is the basis of the two-stage theory of learning, according to which an encounter with a challenging event triggers fast classical conditioning of fear-conditioned responses in the amygdala and slow conditioning of motor-conditioned responses in the cerebellum. A third stage was hypothesised when an apparent interaction between amygdala and cerebellar associative plasticity was observed: an adaptive rate of cerebellum-dependent motor-conditioned responses was associated with a decrease in amygdala-dependent fear-conditioned responses, and was interpreted as extinction of amygdala-related fear-conditioned responses by the cerebellar output. To explore this hypothesis, we mimicked some components of classical eyeblink conditioning in anesthetised rats by applying an aversive periorbital pulse as an unconditioned stimulus and a train of pulses to the cerebellar output nuclei as a cerebellar neuronal-conditioned response. The central amygdala multiple unit response to the periorbital pulse was measured with or without a preceding train to the cerebellar output nuclei. The results showed that activation of the cerebellar output nuclei prior to periorbital stimulation produced diverse patterns of inhibition of the amygdala response to the periorbital aversive stimulus, depending upon the nucleus stimulated, the laterality of the nucleus stimulated, and the stimulus interval used. These results provide a putative extinction mechanism of learned fear behavior, and could have implications for the treatment of pathologies involving abnormal fear responses by using motor training as therapy. © 2014 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  15. Descending projections from the nucleus accumbens shell excite activity of taste-responsive neurons in the nucleus of the solitary tract in the hamster.

    PubMed

    Li, Cheng-Shu; Lu, Da-Peng; Cho, Young K

    2015-06-01

    The nucleus of the solitary tract (NST) and the parabrachial nuclei (PbN) are the first and second relays in the rodent central taste pathway. A series of electrophysiological experiments revealed that spontaneous and taste-evoked activities of brain stem gustatory neurons are altered by descending input from multiple forebrain nuclei in the central taste pathway. The nucleus accumbens shell (NAcSh) is a key neural substrate of reward circuitry, but it has not been verified as a classical gustatory nucleus. A recent in vivo electrophysiological study demonstrated that the NAcSh modulates the spontaneous and gustatory activities of hamster pontine taste neurons. In the present study, we investigated whether activation of the NAcSh modulates gustatory responses of the NST neurons. Extracellular single-unit activity was recorded from medullary neurons in urethane-anesthetized hamsters. After taste response was confirmed by delivery of sucrose, NaCl, citric acid, and quinine hydrochloride to the anterior tongue, the NAcSh was stimulated bilaterally with concentric bipolar stimulating electrodes. Stimulation of the ipsilateral and contralateral NAcSh induced firings from 54 and 37 of 90 medullary taste neurons, respectively. Thirty cells were affected bilaterally. No inhibitory responses or antidromic invasion was observed after NAcSh activation. In the subset of taste cells tested, high-frequency electrical stimulation of the NAcSh during taste delivery enhanced taste-evoked neuronal firing. These results demonstrate that two-thirds of the medullary gustatory neurons are under excitatory descending influence from the NAcSh, which is a strong indication of communication between the gustatory pathway and the mesolimbic reward pathway. Copyright © 2015 the American Physiological Society.

  16. Betting on DBS: Effects of subthalamic nucleus deep brain stimulation on risk taking and decision making in patients with Parkinson's disease.

    PubMed

    Brandt, Jason; Rogerson, Mark; Al-Joudi, Haya; Reckess, Gila; Shpritz, Barnett; Umeh, Chizoba C; Aljehani, Noha; Mills, Kelly; Mari, Zoltan

    2015-07-01

    Concerns persist that deep brain stimulation (DBS) for Parkinson's disease (PD) increases impulsivity or induces excessive reward seeking. We report here the performance of PD patients with implanted subthalamic nucleus electrodes, with stimulation on and off, on 3 laboratory tasks of risk taking and decision making. They are compared with PD patients maintained on medication and healthy participants. In the Game of Dice Task, a test of "risky" decision making, PD patients with or without DBS made highest risk bets more often and ended up with less money than did healthy participants. There was a trend for DBS stimulation to ameliorate this effect. Deal or No-Deal is an "ambiguous" decision-making task that assessed preference for risk (holding on to one's briefcase) over a "sure thing" (accepting the banker's offer). Here, DBS patients were more conservative with stimulation on than with it off. They accepted smaller offers from the banker and won less money in the DBS-on condition. Overall, the 2 PD groups won less money than did healthy participants. The Framing Paradigm assessed willingness to gamble on a fixed (unambiguous) prize depending on whether the reward was "framed" as a loss or a gain. Nonsurgical PD patients tended to be more risk-averse than were healthy participants, whereas DBS patients were more willing to gamble for gains as well as losses both on and off stimulation. On risky decision-making tasks, DBS patients took more risks than did healthy participants, but stimulation may temper this tendency. In contrast, in an ambiguous-risk situation, DBS patients were more risk-averse (conservative) than were healthy participants, and this tendency was greatest with stimulation. (c) 2015 APA, all rights reserved).

  17. [Site of prelingual cochlear stimulation and its effect on electrically evoked compound action potentials and refractory using the Nucleus 24 standard].

    PubMed

    Ma, R Y; Li, W; Jiang, X J

    2016-12-01

    Objective: To investigate the correlation between the site of prelingual cochlear stimulation and its effect on electrically evoked compound action potentials. Method: Recordings of auditory nerve responses were conducted in 32 prelingual subjects to demonstrate the feasibility of ECAP recordings using the nerve response telemetry(NRT) feature of the Nucleus CI24R(CA) system software. These recordings were then analyzed based on the site of cochlear stimulation defined as basal, middle and apical to determine if the amplitude, threshold and slope of the amplitude growth function and the refractory time differs depending on the region of stimulation. Result: Findings of our prelingual children showed significant differences in the ECAP recordings depending on the stimulation site. Comparing the apical with the basal region, on average higher amplitudes, lower thresholds and steeper slopes of the amplitude growth function hadbeen observed. The refractory time showed an overall dependence on cochlear region; however post-hoc tests showed no significant effect between individual regions. Conclusion: Obtaining ECAP recordings is also possible in the most apical region of the cochlea. However, differences can be observed depending on the region of the cochlea stimulated. Specifically, significant higher ECAP amplitude, lower thresholds and steeper amplitude growth function slopes have been observed in the apical region. These differences between prelingual children and adults could be explained by the location of the stimulating electrode with respect to the neural tissue in the cochlea, a higher density, or an increased neural survival rate of neural tissue in the apex. Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.

  18. The central nucleus of the amygdala modulates gut-related neurons in the dorsal vagal complex in rats

    PubMed Central

    Zhang, Xueguo; Cui, Jinjuan; Tan, Zhenjun; Jiang, Chunhui; Fogel, Ronald

    2003-01-01

    Using retrograde tract-tracing and electrophysiological methods, we characterized the anatomical and functional relationship between the central nucleus of the amygdala and the dorsal vagal complex. Retrograde tract-tracing techniques revealed that the central nucleus of the amygdala projects to the dorsal vagal complex with a topographic distribution. Following injection of retrograde tracer into the vagal complex, retrogradely labelled neurons in the central nucleus of the amygdala were clustered in the central portion at the rostral level and in the medial part at the middle level of the nucleus. Few labelled neurons were seen at the caudal level. Electrical stimulation of the central nucleus of the amygdala altered the basal firing rates of 65 % of gut-related neurons in the nucleus of the solitary tract and in the dorsal motor nucleus of the vagus. Eighty-one percent of the neurons in the nucleus of the solitary tract and 47 % of the neurons in the dorsal motor nucleus were inhibited. Electrical stimulation of the central nucleus of the amygdala also modulated the response of neurons in the dorsal vagal complex to gastrointestinal stimuli. The predominant effect on the neurons of the nucleus of the solitary tract was inhibition. These results suggest that the central nucleus of the amygdala influences gut-related neurons in the dorsal vagal complex and provides a neuronal circuitry that explains the regulation of gastrointestinal activity by the amygdala. PMID:14555729

  19. Electrical stimulation of rhesus monkey nucleus reticularis gigantocellularis. II. Effects on metrics and kinematics of ongoing gaze shifts to visual targets.

    PubMed

    Freedman, Edward G; Quessy, Stephan

    2004-06-01

    Saccade kinematics are altered by ongoing head movements. The hypothesis that a head movement command signal, proportional to head velocity, transiently reduces the gain of the saccadic burst generator (Freedman 2001, Biol Cybern 84:453-462) can account for this observation. Using electrical stimulation of the rhesus monkey nucleus reticularis gigantocellularis (NRG) to alter the head contribution to ongoing gaze shifts, two critical predictions of this gaze control hypothesis were tested. First, this hypothesis predicts that activation of the head command pathway will cause a transient reduction in the gain of the saccadic burst generator. This should alter saccade kinematics by initially reducing velocity without altering saccade amplitude. Second, because this hypothesis does not assume that gaze amplitude is controlled via feedback, the added head contribution (produced by NRG stimulation on the side ipsilateral to the direction of an ongoing gaze shift) should lead to hypermetric gaze shifts. At every stimulation site tested, saccade kinematics were systematically altered in a way that was consistent with transient reduction of the gain of the saccadic burst generator. In addition, gaze shifts produced during NRG stimulation were hypermetric compared with control movements. For example, when targets were briefly flashed 30 degrees from an initial fixation location, gaze shifts during NRG stimulation were on average 140% larger than control movements. These data are consistent with the predictions of the tested hypothesis, and may be problematic for gaze control models that rely on feedback control of gaze amplitude, as well as for models that do not posit an interaction between head commands and the saccade burst generator.

  20. Pilot Study Assessing the Feasibility of Applying Bilateral Subthalamic Nucleus Deep Brain Stimulation in Very Early Stage Parkinson's Disease: Study design and rationale

    PubMed Central

    Charles, David; Tolleson, Christopher; Davis, Thomas L.; Gill, Chandler E.; Molinari, Anna L.; Bliton, Mark J.; Tramontana, Michael G.; Salomon, Ronald M.; Kao, Chris; Wang, Lily; Hedera, Peter; Phibbs, Fenna T.; Neimat, Joseph S.; Konrad, Peter E.

    2014-01-01

    Background Deep brain stimulation provides significant symptomatic benefit for people with advanced Parkinson's disease whose symptoms are no longer adequately controlled with medication. Preliminary evidence suggests that subthalamic nucleus stimulation may also be efficacious in early Parkinson's disease, and results of animal studies suggest that it may spare dopaminergic neurons in the substantia nigra. Objective We report the methodology and design of a novel Phase I clinical trial testing the safety and tolerability of deep brain stimulation in early Parkinson's disease and discuss previous failed attempts at neuroprotection. Methods We recently conducted a prospective, randomized, parallel-group, single-blind pilot clinical trial of deep brain stimulation in early Parkinson's disease. Subjects were randomized to receive either optimal drug therapy or deep brain stimulation plus optimal drug therapy. Follow-up visits occurred every six months for a period of two years and included week-long therapy washouts. Results Thirty subjects with Hoehn & Yahr Stage II idiopathic Parkinson's disease were enrolled over a period of 32 months. Twenty-nine subjects completed all follow-up visits; one patient in the optimal drug therapy group withdrew from the study after baseline. Baseline characteristics for all thirty patients were not significantly different. Conclusions This study demonstrates that it is possible to recruit and retain subjects in a clinical trial testing deep brain stimulation in early Parkinson's disease. The results of this trial will be used to support the design of a Phase III, multicenter trial investigating the efficacy of deep brain stimulation in early Parkinson's disease. PMID:23938229

  1. Patients' expectations in subthalamic nucleus deep brain stimulation surgery for Parkinson disease.

    PubMed

    Hasegawa, Harutomo; Samuel, Michael; Douiri, Abdel; Ashkan, Keyoumars

    2014-12-01

    Subthalamic nucleus (STN) deep brain stimulation (DBS) is an established treatment for patients with advanced Parkinson disease. However, some patients feel less satisfied with the outcome of surgery. We sought to study the relationship between expectations, satisfaction, and outcome in STN DBS for Parkinson disease. Twenty-two consecutive patients undergoing STN DBS completed a modified 39-item Parkinson disease questionnaire (PDQ-39) preoperatively and 6 months postoperatively. A satisfaction questionnaire accompanied the postoperative questionnaire. Patients expected a significant improvement from surgery preoperatively: preoperative score (median PDQ-39 summary score [interquartile range]): 37.0 (9.5), expected postoperative score: 13.0 (8.0), P < 0.001. Patients improved after surgery (preoperative score 39.0 [11.5], postoperative score 25.0 [14.3], P = 0.003), although there was a substantial disparity between the expected change (24.0 [15.0]) and actual change (14.0 [22.5]), P = 0.008. However, most patients felt that surgery fulfilled their expectations (mean score on a 0%-100% visual analog scale); (75.3 ± 17.8) and were satisfied (73.3 ± 25.3). Satisfaction correlated with fulfillment of expectations (r = 0.910, P < 0.001) but not with quantitative changes in PDQ-39 scores. Addressing patients' expectations both preoperatively and postoperatively may play an important role in patient satisfaction, and therefore overall success, of STN DBS surgery for Parkinson disease. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. Motor dysfunction and alterations in glutathione concentration, cholinesterase activity, and BDNF expression in substantia nigra pars compacta in rats with pedunculopontine lesion.

    PubMed

    Blanco-Lezcano, Lisette; Jimenez-Martin, Javier; Díaz-Hung, Mei-Li; Alberti-Amador, Esteban; Wong-Guerra, Maylin; González-Fraguela, Ma Elena; Estupiñán-Díaz, Bárbara; Serrano-Sánchez, Teresa; Francis-Turner, Liliana; Delgado-Ocaña, Susana; Núñez-Figueredo, Yanier; Vega-Hurtado, Yamilé; Fernández-Jiménez, Isabel

    2017-04-21

    Pedunculopontine nucleus (PPN) has been considered a critically important region in the regulation of some of the physiological functions that fail during the progression of Parkinson's disease (PD). In this paper, the effects of unilateral neurotoxic lesion of the PPN [through the injection of N-methyl-d-aspartate (NMDA) solution (concentration: 0.1M; volume: 0.5µL)] in motor execution and gait disorders and the changes in cellular and molecular indicators in rat nigral tissue were evaluated. The motor execution was assessed using the beam test (BT) and the gait disorders by footprint test. Glutathione (GSH) concentrations, acetyl cholinesterase enzymatic activity (AChE EA), and brain-derived neurotrophic factor (BDNF) mRNA expression in nigral tissue were analyzed. NMDA-lesioned rats showed fine motor dysfunction with a significant increase in the slow (p≤0.01) and fast movement (p≤0.01) time and in path deviation (p≤0.01) on the smaller diameter beams. Moreover, NMDA-lesioned rats exhibited an imprecise path with moments of advances and setbacks, alternating with left and right deviations, suspensions, and inverted positions. Footprint test revealed slight gait disorders, which were manifested by a reduction in the left and right stride lengths, the intra-step distance, and the support area (p≤0.01). Biochemical studies showed that 48h after the PPN neurotoxic injury, the GSH concentrations and BDNF expression were significantly increased (p≤0.01). These variables returned to normal values 7days after the PPN lesion; the AChE EA showed a significant increase at this time. These functional changes in nigral tissue could be a plastic responses associated with early PD. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

  3. [Response of vasopressin and tyrosine hydroxylase expressing neurons of the rat supraoptic nucleus to chronic osmotic stimulation].

    PubMed

    Abramova, M A; Calas, A; Maiily, P; Thibault, J; Ugriumov, M V

    1999-06-01

    This study has evaluated the dynamic of intracellular vasopressin and tyrosine hydroxylase contents in the neuron cell bodies in the supraoptic nucleus and in the axons of the posterior lobe in rats drinking 2% NaCl for 1, 2, and 3 weeks. The number of vasopressin-immunoreactive neurons increased by the end of the second week of osmotic stimulation that might be explained by the onset of vasopressin synthesis in the neurons which do not synthesize this neurohormone under normal physiological conditions. The concentration of vasopressin fell down continuously during the first two weeks of salt-loading, apparently, due to predominance of the vasopressin release over its synthesis. Over the third week of salt-loading, the intracellular concentration of vasopressin was not changed significantly suggesting the establishment of the dynamic equilibrium between the vasopressin synthesis and release. The number of tyrosine hydroxylase-immunoreactive neurons and the amount of tyrosine hydroxylase in cell bodies and the large axonal swellings, Herring bodies, increased gradually showing that the rate of tyrosine hydroxylase synthesis prevailed over that of its enzymatic degradation. Thus, the chronic stimulation of vasopressin neurons is accompanied by a number of the adaptive reactions; the most important is related to the onset of vasopressin and tyrosine hydroxylase synthesis in the neurons which do not synthetize both of them under normal conditions.

  4. [Comparative study of effects of cortical nucleus of amygdala and pyriform cortex on activity of bulbar respiratory neurons in cats].

    PubMed

    Nersesian, L B; Eganova, V S; Pogosian, N L; Avetisian, I N

    2011-01-01

    Comparative microelectrophysiological study of character and peculiarities of effects of the cortical nucleus of amygdala and of the periamygdalar area of pyriform cortex on impulse activity was performed on the same single functionally identified respiratory medullar neurons. A high reactivity of bulbar respiratory neurons on stimulation is established in both studied limbic structures. There is established the qualitatively different character of their response reactions at stimulation of the cortical amygdala nucleus and the periamygdalar cortex. The cortical amygdala nucleus has been shown to produce on the activity of medullar respiratory neurons both facilitating and inhibitory action with predominance of the activating one (without topographical orderliness). The effect of periamygdalar cortex at stimulation of various parts was characterized by topographic differentiation. The suppressing reactions of neurons in the majority of cases were recorded at stimulation of the rostral area of periamygdalar cortex, whereas the excitatory reactions--at stimulation of its caudal part. Functional organization of respiratory control of the studied limbic system structures is discussed.

  5. Inclusion of Cocoa as a Dietary Supplement Represses Expression of Inflammatory Proteins in Spinal Trigeminal Nucleus in Response to Chronic Trigeminal Nerve Stimulation

    PubMed Central

    Cady, Ryan J.; Denson, Jennifer E.; Durham, Paul L.

    2013-01-01

    Scope Central sensitization is implicated in the pathology of temporomandibular joint disorder (TMD) and other types of orofacial pain. We investigated the effects of dietary cocoa on expression of proteins involved in the development of central sensitization in the spinal trigeminal nucleus (STN) in response to inflammatory stimulation of trigeminal nerves. Methods and results Male Sprague Dawley rats were fed either a control diet or an isocaloric diet consisting of 10% cocoa powder 14 days prior to bilateral injection of complete Freund’s adjuvant (CFA) into the temporomandibular joint to promote prolonged activation of trigeminal ganglion neurons and glia. While dietary cocoa stimulated basal expression of GLAST and MKP-1 when compared to animals on a normal diet, cocoa suppressed basal calcitonin gene-related peptide levels in the STN. CFA-stimulated levels of protein kinase A, P2X3, P-p38, GFAP, and OX-42, whose elevated levels in the STN are implicated in central sensitization, were repressed to near control levels in animals on a cocoa enriched diet. Similarly, dietary cocoa repressed CFA-stimulated inflammatory cytokine expression. Conclusion Based on our findings, we speculate that cocoa enriched diets could be beneficial as a natural therapeutic option for TMD and other chronic orofacial pain conditions. PMID:23576361

  6. Effect of subthalamic nucleus stimulation during exercise on the mesolimbocortical dopaminergic region in Parkinson's disease: a positron emission tomography study.

    PubMed

    Nozaki, Takao; Sugiyama, Kenji; Yagi, Shunsuke; Yoshikawa, Etsuji; Kanno, Toshihiko; Asakawa, Tetsuya; Ito, Tae; Terada, Tatsuhiro; Namba, Hiroki; Ouchi, Yasuomi

    2013-03-01

    To elucidate the dynamic effects of deep brain stimulation (DBS) in the subthalamic nucleus (STN) during activity on the dopaminergic system, 12 PD patients who had STN-DBS operations at least 1 month prior, underwent two positron emission tomography scans during right-foot movement in DBS-off and DBS-on conditions. To quantify motor performance changes, the motion speed and mobility angle of the foot at the ankle were measured twice. Estimations of the binding potential of [(11)C]raclopride (BP(ND)) were based on the Logan plot method. Significant motor recovery was found in the DBS-on condition. The STN-DBS during exercise significantly reduced the [(11)C]raclopride BP(ND) in the caudate and the nucleus accumbens (NA), but not in the dorsal or ventral putamen. The magnitude of dopamine release in the NA correlated negatively with the magnitude of motor load, indicating that STN-DBS facilitated motor behavior more smoothly and at less expense to dopamine neurons in the region. The lack of dopamine release in the putamen and the significant dopamine release in the ventromedial striatum by STN-DBS during exercise indicated dopaminergic activation occurring in the motivational circuit during action, suggesting a compensatory functional activation of the motor loop from the nonmotor to the motor loop system.

  7. High frequency stimulation of the entopeduncular nucleus sets the cortico-basal ganglia network to a new functional state in the dystonic hamster.

    PubMed

    Reese, René; Charron, Giselle; Nadjar, Agnès; Aubert, Incarnation; Thiolat, Marie-Laure; Hamann, Melanie; Richter, Angelika; Bezard, Erwan; Meissner, Wassilios G

    2009-09-01

    High frequency stimulation (HFS) of the internal pallidum is effective for the treatment of dystonia. Only few studies have investigated the effects of stimulation on the activity of the cortex-basal ganglia network. We here assess within this network the effect of entopeduncular nucleus (EP) HFS on the expression of c-Fos and cytochrome oxidase subunit I (COI) in the dt(sz)-hamster, a well-characterized model of paroxysmal dystonia. In dt(sz)-hamsters, we identified abnormal activity in motor cortex, basal ganglia and thalamus. These structures have already been linked to the pathophysiology of human dystonia. EP-HFS (i) increased striatal c-Fos expression in controls and dystonic hamsters and (ii) reduced thalamic c-Fos expression in dt(sz)-hamsters. EP-HFS had no effect on COI expression. The present results suggest that EP-HFS induces a new network activity state which may improve information processing and finally reduces the severity of dystonic attacks in dt(sz)-hamsters.

  8. Coherence and frequency in the reticular activating system (RAS)

    PubMed Central

    Garcia-Rill, Edgar; Kezunovic, Nebojsa; Hyde, James; Simon, Christen; Beck, Paige; Urbano, Francisco J.

    2012-01-01

    SUMMARY This review considers recent evidence showing that cells in the reticular activating system (RAS) exhibit 1) electrical coupling mainly in GABAergic cells, and 2) gamma band activity in virtually all of the cells. Specifically, cells in the mesopontine pedunculopontine nucleus (PPN), intralaminar parafascicular nucleus (Pf), and pontine dorsal subcoeruleus nucleus dorsalis (SubCD) 1) show electrical coupling, and 2) all fire in the beta/gamma band range when maximally activated, but no higher. The mechanism behind electrical coupling is important because the stimulant modafinil was shown to increase electrical coupling. We also provide recent findings demonstrating that all cells in the PPN and Pf have high threshold, voltage-dependent P/Q-type calcium channels that are essential to gamma band activity. On the other hand, all SubCD, and some PPN, cells manifested sodium-dependent subthreshold oscillations. A novel mechanism for sleep-wake control based on transmitter interactions, electrical coupling, and gamma band activity is described. We speculate that continuous sensory input will modulate coupling and induce gamma band activity in the RAS that could participate in the processes of preconscious awareness, and provide the essential stream of information for the formulation of many of our actions. PMID:23044219

  9. Coherence and frequency in the reticular activating system (RAS).

    PubMed

    Garcia-Rill, Edgar; Kezunovic, Nebojsa; Hyde, James; Simon, Christen; Beck, Paige; Urbano, Francisco J

    2013-06-01

    This review considers recent evidence showing that cells in the reticular activating system (RAS) exhibit (1) electrical coupling mainly in GABAergic cells, and (2) gamma band activity in virtually all of the cells. Specifically, cells in the mesopontine pedunculopontine nucleus (PPN), intralaminar parafascicular nucleus (Pf), and pontine dorsal subcoeruleus nucleus dorsalis (SubCD) (1) show electrical coupling, and (2) all fire in the beta/gamma band range when maximally activated, but no higher. The mechanism behind electrical coupling is important because the stimulant modafinil was shown to increase electrical coupling. We also provide recent findings demonstrating that all cells in the PPN and Pf have high threshold, voltage-dependent P/Q-type calcium channels that are essential to gamma band activity. On the other hand, all SubCD, and some PPN, cells manifested sodium-dependent subthreshold oscillations. A novel mechanism for sleep-wake control based on transmitter interactions, electrical coupling, and gamma band activity is described. We speculate that continuous sensory input will modulate coupling and induce gamma band activity in the RAS that could participate in the processes of preconscious awareness, and provide the essential stream of information for the formulation of many of our actions. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. Betting on DBS: Effects of Subthalamic Nucleus Deep Brain Stimulation on Risk-Taking and Decision-Making in Patients with Parkinson’s Disease

    PubMed Central

    Brandt, Jason; Rogerson, Mark; Al-Joudi, Haya; Reckess, Gila; Shpritz, Barnett; Umeh, Chizoba C.; Aljehani, Noha; Mills, Kelly; Mari, Zoltan

    2014-01-01

    Objective Concerns persist that deep brain stimulation (DBS) for Parkinson’s disease (PD) increases impulsivity and/or induces excessive reward-seeking. We report here the performance of PD patients with implanted subthalamic nucleus electrodes, with stimulation on and off, on three laboratory tasks of risk-taking and decision-making. They are compared to PD patients maintained on medication and normal control subjects. Methods and Results In the Game of Dice Task, a test of “risky” decision-making, PD patients with or without DBS made highest-risk bets more often, and ended up with less money, than normal controls. There was a trend for DBS stimulation to ameliorate this effect. Deal or No-Deal is an “ambiguous” decision-making task that assessed preference for risk (holding on to one’s briefcase) over a “sure thing” (accepting the banker’s offer). Here, DBS patients were more conservative with stimulation on than off. They accepted smaller offers from the banker and won less money in the DBS-on condition. Overall, the two PD groups won less money than healthy participants. The Framing Paradigm assessed willingness to gamble on a fixed (unambiguous) prize depending on whether the reward was “framed” as a loss or a gain. Nonsurgical PD patients tended to be more risk-averse than normal subjects, whereas DBS patients were more willing to gamble for gains as well as losses both on and off stimulation. Conclusions On “risky” decision-making tasks, DBS patients were more risk-taking than normal, but stimulation may temper this tendency. In contrast, in an “ambiguous risk” situation, DBS patients were more risk-averse (conservative) than normal, and this tendency was greatest with stimulation. PMID:25486385

  11. Laterodorsal nucleus of the thalamus: A processor of somatosensory inputs.

    PubMed

    Bezdudnaya, Tatiana; Keller, Asaf

    2008-04-20

    The laterodorsal (LD) nucleus of the thalamus has been considered a "higher order" nucleus that provides inputs to limbic cortical areas. Although its functions are largely unknown, it is often considered to be involved in spatial learning and memory. Here we provide evidence that LD is part of a hitherto unknown pathway for processing somatosensory information. Juxtacellular and extracellular recordings from LD neurons reveal that they respond to vibrissa stimulation with short latency (median = 7 ms) and large magnitude responses (median = 1.2 spikes/stimulus). Most neurons (62%) had large receptive fields, responding to six and more individual vibrissae. Electrical stimulation of the trigeminal nucleus interpolaris (SpVi) evoked short latency responses (median = 3.8 ms) in vibrissa-responsive LD neurons. Labeling produced by anterograde and retrograde neuroanatomical tracers confirmed that LD neurons receive direct inputs from SpVi. Electrophysiological and neuroanatomical analyses revealed also that LD projects upon the cingulate and retrosplenial cortex, but has only sparse projections to the barrel cortex. These findings suggest that LD is part of a novel processing stream involved in spatial orientation and learning related to somatosensory cues. (c) 2008 Wiley-Liss, Inc.

  12. Laterodorsal Nucleus of the Thalamus: A Processor of Somatosensory Inputs

    PubMed Central

    BEZDUDNAYA, TATIANA; KELLER, ASAF

    2009-01-01

    The laterodorsal (LD) nucleus of the thalamus has been considered a “higher order” nucleus that provides inputs to limbic cortical areas. Although its functions are largely unknown, it is often considered to be involved in spatial learning and memory. Here we provide evidence that LD is part of a hitherto unknown pathway for processing somatosensory information. Juxtacellular and extracellular recordings from LD neurons reveal that they respond to vibrissa stimulation with short latency (median = 7 ms) and large magnitude responses (median = 1.2 spikes/stimulus). Most neurons (62%) had large receptive fields, responding to six and more individual vibrissae. Electrical stimulation of the trigeminal nucleus interpolaris (SpVi) evoked short latency responses (median = 3.8 ms) in vibrissa-responsive LD neurons. Labeling produced by anterograde and retrograde neuroanatomical tracers confirmed that LD neurons receive direct inputs from SpVi. Electrophysiological and neuroanatomical analyses revealed also that LD projects upon the cingulate and retrosplenial cortex, but has only sparse projections to the barrel cortex. These findings suggest that LD is part of a novel processing stream involved in spatial orientation and learning related to somatosensory cues. PMID:18273888

  13. Frequency-specific corticofugal modulation of the dorsal cochlear nucleus in mice.

    PubMed

    Kong, Lingzhi; Xiong, Colin; Li, Liang; Yan, Jun

    2014-01-01

    The primary auditory cortex (AI) modulates the sound information processing in the lemniscal subcortical nuclei, including the anteroventral cochlear nucleus (AVCN), in a frequency-specific manner. The dorsal cochlear nucleus (DCN) is a non-lemniscal subcortical nucleus but it is tonotopically organized like the AVCN. However, it remains unclear how the AI modulates the sound information processing in the DCN. This study examined the impact of focal electrical stimulation of AI on the auditory responses of the DCN neurons in mice. We found that the electrical stimulation induced significant changes in the best frequency (BF) of DCN neurons. The changes in the BFs were highly specific to the BF differences between the stimulated AI neurons and the recorded DCN neurons. The DCN BFs shifted higher when the AI BFs were higher than the DCN BFs and the DCN BFs shifted lower when the AI BFs were lower than the DCN BFs. The DCN BFs showed no change when the AI and DCN BFs were similar. Moreover, the BF shifts were linearly correlated to the BF differences. Thus, our data suggest that corticofugal modulation of the DCN is also highly specific to frequency information, similar to the corticofugal modulation of the AVCN. The frequency-specificity of corticofugal modulation does not appear limited to the lemniscal ascending pathway.

  14. Posterolateral Trajectories Favor a Longer Motor Domain in Subthalamic Nucleus Deep Brain Stimulation for Parkinson Disease.

    PubMed

    Tamir, Idit; Marmor-Levin, Odeya; Eitan, Renana; Bergman, Hagai; Israel, Zvi

    2017-10-01

    The clinical outcome of patients with Parkinson disease (PD) who undergo subthalamic nucleus (STN) deep brain stimulation (DBS) is, in part, determined by the length of the electrode trajectory through the motor STN domain, the dorsolateral oscillatory region (DLOR). Trajectory length has been found to correlate with the stimulation-related improvement in patients' motor function (estimated by part III of the United Parkinson's Disease Rating Scale [UPDRS]). Therefore, it seems that ideally trajectories should have maximal DLOR length. We retrospectively studied the influence of various anatomic aspects of the brains of patients with PD and the geometry of trajectories planned on the length of the DLOR and STN recorded during DBS surgery. We examined 212 trajectories and 424 microelectrode recording tracks in 115 patients operated on in our center between 2010 and 2015. We found a strong correlation between the length of the recorded DLOR and STN. Trajectories that were more lateral and/or posterior in orientation had a longer STN and DLOR pass, although the DLOR/STN fraction length remained constant. The STN target was more lateral when the third ventricle was wider, and the latter correlated with older age and male gender. Trajectory angles correlate with the recorded STN and DLOR lengths, and should be altered toward a more posterolateral angle in older patients and atrophied brains to compensate for the changes in STN location and geometry. These fine adjustments should yield a longer motor domain pass, thereby improving the patient's predicted outcome. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Resting state functional MRI in Parkinson's disease: the impact of deep brain stimulation on 'effective' connectivity.

    PubMed

    Kahan, Joshua; Urner, Maren; Moran, Rosalyn; Flandin, Guillaume; Marreiros, Andre; Mancini, Laura; White, Mark; Thornton, John; Yousry, Tarek; Zrinzo, Ludvic; Hariz, Marwan; Limousin, Patricia; Friston, Karl; Foltynie, Tom

    2014-04-01

    Depleted of dopamine, the dynamics of the parkinsonian brain impact on both 'action' and 'resting' motor behaviour. Deep brain stimulation has become an established means of managing these symptoms, although its mechanisms of action remain unclear. Non-invasive characterizations of induced brain responses, and the effective connectivity underlying them, generally appeals to dynamic causal modelling of neuroimaging data. When the brain is at rest, however, this sort of characterization has been limited to correlations (functional connectivity). In this work, we model the 'effective' connectivity underlying low frequency blood oxygen level-dependent fluctuations in the resting Parkinsonian motor network-disclosing the distributed effects of deep brain stimulation on cortico-subcortical connections. Specifically, we show that subthalamic nucleus deep brain stimulation modulates all the major components of the motor cortico-striato-thalamo-cortical loop, including the cortico-striatal, thalamo-cortical, direct and indirect basal ganglia pathways, and the hyperdirect subthalamic nucleus projections. The strength of effective subthalamic nucleus afferents and efferents were reduced by stimulation, whereas cortico-striatal, thalamo-cortical and direct pathways were strengthened. Remarkably, regression analysis revealed that the hyperdirect, direct, and basal ganglia afferents to the subthalamic nucleus predicted clinical status and therapeutic response to deep brain stimulation; however, suppression of the sensitivity of the subthalamic nucleus to its hyperdirect afferents by deep brain stimulation may subvert the clinical efficacy of deep brain stimulation. Our findings highlight the distributed effects of stimulation on the resting motor network and provide a framework for analysing effective connectivity in resting state functional MRI with strong a priori hypotheses.

  16. Differential regulation of serotonin-1A receptor stimulated [35S]GTPγS binding in the dorsal raphe nucleus by citalopram and escitalopram

    PubMed Central

    Rossi, Dania V.; Burke, Teresa F.; Hensler, Julie G.

    2008-01-01

    The effect of chronic citalopram or escitalopram administration on 5-HT1A receptor function in the dorsal raphe nucleus was determined by measuring [35S]GTPγS binding stimulated by the 5-HT1A receptor agonist (R)-(+)-8-OH-DPAT (1nM-10μM). Although chronic administration of citalopram or escitalopram has been shown to desensitize somatodendritic 5-HT1A autoreceptors, we found that escitalopram treatment decreased the efficacy of 5-HT1A receptors to activate G-proteins, whereas citalopram treatment did not. The binding of [3H]8-OH-DPAT to the coupled, high affinity agonist state of the receptor was not altered by either treatment. Interestingly, escitalopram administration resulted in greater occupancy of serotonin transporter sites as measured by the inhibition of [3H]cyanoimipramine binding. As the binding and action of escitalopram is limited by the inactive enantiomer R-citalopram present in racemic citalopram, we propose that the regulation of 5-HT1A receptor function in the dorsal raphe nucleus at the level of receptor-G protein interaction may be a result of greater inhibition of the serotonin transporter by escitalopram. PMID:18289523

  17. GLP-1 Receptor Stimulation of the Lateral Parabrachial Nucleus Reduces Food Intake: Neuroanatomical, Electrophysiological, and Behavioral Evidence

    PubMed Central

    Richard, Jennifer E.; Farkas, Imre; Anesten, Fredrik; Anderberg, Rozita H.; Dickson, Suzanne L.; Gribble, Fiona M.; Reimann, Frank; Jansson, John-Olov; Liposits, Zsolt

    2014-01-01

    The parabrachial nucleus (PBN) is a key nucleus for the regulation of feeding behavior. Inhibitory inputs from the hypothalamus to the PBN play a crucial role in the normal maintenance of feeding behavior, because their loss leads to starvation. Viscerosensory stimuli result in neuronal activation of the PBN. However, the origin and neurochemical identity of the excitatory neuronal input to the PBN remain largely unexplored. Here, we hypothesize that hindbrain glucagon-like peptide 1 (GLP-1) neurons provide excitatory inputs to the PBN, activation of which may lead to a reduction in feeding behavior. Our data, obtained from mice expressing the yellow fluorescent protein in GLP-1-producing neurons, revealed that hindbrain GLP-1-producing neurons project to the lateral PBN (lPBN). Stimulation of lPBN GLP-1 receptors (GLP-1Rs) reduced the intake of chow and palatable food and decreased body weight in rats. It also activated lPBN neurons, reflected by an increase in the number of c-Fos-positive cells in this region. Further support for an excitatory role of GLP-1 in the PBN is provided by electrophysiological studies showing a remarkable increase in firing of lPBN neurons after Exendin-4 application. We show that within the PBN, GLP-1R activation increased gene expression of 2 energy balance regulating peptides, calcitonin gene-related peptide (CGRP) and IL-6. Moreover, nearly 70% of the lPBN GLP-1 fibers innervated lPBN CGRP neurons. Direct intra-lPBN CGRP application resulted in anorexia. Collectively, our molecular, anatomical, electrophysiological, pharmacological, and behavioral data provide evidence for a functional role of the GLP-1R for feeding control in the PBN. PMID:25116706

  18. Low-frequency stimulation in anterior nucleus of thalamus alleviates kainate-induced chronic epilepsy and modulates the hippocampal EEG rhythm.

    PubMed

    Wang, Yi; Liang, Jiao; Xu, Cenglin; Wang, Ying; Kuang, Yifang; Xu, Zhenghao; Guo, Yi; Wang, Shuang; Gao, Feng; Chen, Zhong

    2016-02-01

    High-frequency stimulation (HFS) of the anterior nucleus of thalamus (ANT) is a new and alternative option for the treatment of intractable epilepsy. However, the responder rate is relatively low. The present study was designed to determine the effect of low-frequency stimulation (LFS) in ANT on chronic spontaneous recurrent seizures and related pathological pattern in intra-hippocampal kainate mouse model. We found that LFS (1 Hz, 100 μs, 300 μA), but not HFS (100 Hz, 100 μs, 30 μA), in bilateral ANT significantly decreased the frequency of spontaneous recurrent seizures, either non-convulsive focal seizures or tonic-clonic generalized seizures. The anti-epileptic effect persisted for one week after LFS cessation, which manifested as a long-term inhibition of the frequency of seizures with short (20-60 s) and intermediate duration (60-120 s). Meanwhile, LFS decreased the frequency of high-frequency oscillations (HFOs) and interictal spikes, two indicators of seizure severity, whereas HFS increased the HFO frequency. Furthermore, LFS decreased the power of the delta band and increased the power of the gamma band of hippocampal background EEG. In addition, LFS, but not HFS, improved the performance of chronic epileptic mice in objection-location task, novel objection recognition and freezing test. These results provide the first evidence that LFS in ANT alleviates kainate-induced chronic epilepsy and cognitive impairment, which may be related to the modulation of the hippocampal EEG rhythm. This may be of great therapeutic significance for clinical treatment of epilepsy with deep brain stimulation. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. Convergence of limb, visceral, and vertical semicircular canal or otolith inputs onto vestibular nucleus neurons

    NASA Technical Reports Server (NTRS)

    Jian, B. J.; Shintani, T.; Emanuel, B. A.; Yates, B. J.

    2002-01-01

    The major goal of this study was to determine the patterns of convergence of non-labyrinthine inputs from the limbs and viscera onto vestibular nucleus neurons receiving signals from vertical semicircular canals or otolith organs. A secondary aim was to ascertain whether the effects of non-labyrinthine inputs on the activity of vestibular nucleus neurons is affected by bilateral peripheral vestibular lesions. The majority (72%) of vestibular nucleus neurons in labyrinth-intact animals whose firing was modulated by vertical rotations responded to electrical stimulation of limb and/or visceral nerves. The activity of even more vestibular nucleus neurons (93%) was affected by limb or visceral nerve stimulation in chronically labyrinthectomized preparations. Some neurons received non-labyrinthine inputs from a variety of peripheral sources, including antagonist muscles acting at the same joint, whereas others received inputs from more limited sources. There was no apparent relationship between the spatial and dynamic properties of a neuron's responses to tilts in vertical planes and the non-labyrinthine inputs that it received. These data suggest that non-labyrinthine inputs elicited during movement will modulate the processing of information by the central vestibular system, and may contribute to the recovery of spontaneous activity of vestibular nucleus neurons following peripheral vestibular lesions. Furthermore, some vestibular nucleus neurons with non-labyrinthine inputs may be activated only during particular behaviors that elicit a specific combination of limb and visceral inputs.

  20. Convergence of limb, visceral, and vertical semicircular canal or otolith inputs onto vestibular nucleus neurons.

    PubMed

    Jian, B J; Shintani, T; Emanuel, B A; Yates, B J

    2002-05-01

    The major goal of this study was to determine the patterns of convergence of non-labyrinthine inputs from the limbs and viscera onto vestibular nucleus neurons receiving signals from vertical semicircular canals or otolith organs. A secondary aim was to ascertain whether the effects of non-labyrinthine inputs on the activity of vestibular nucleus neurons is affected by bilateral peripheral vestibular lesions. The majority (72%) of vestibular nucleus neurons in labyrinth-intact animals whose firing was modulated by vertical rotations responded to electrical stimulation of limb and/or visceral nerves. The activity of even more vestibular nucleus neurons (93%) was affected by limb or visceral nerve stimulation in chronically labyrinthectomized preparations. Some neurons received non-labyrinthine inputs from a variety of peripheral sources, including antagonist muscles acting at the same joint, whereas others received inputs from more limited sources. There was no apparent relationship between the spatial and dynamic properties of a neuron's responses to tilts in vertical planes and the non-labyrinthine inputs that it received. These data suggest that non-labyrinthine inputs elicited during movement will modulate the processing of information by the central vestibular system, and may contribute to the recovery of spontaneous activity of vestibular nucleus neurons following peripheral vestibular lesions. Furthermore, some vestibular nucleus neurons with non-labyrinthine inputs may be activated only during particular behaviors that elicit a specific combination of limb and visceral inputs.

  1. The nucleus raphe magnus suppresses vomiting, and the solitary nucleus and 5-HT are not involved in this suppression.

    PubMed

    Hattori, Yuka; Hamaguchi, Chie; Yamada, Yuko; Urayama, Yukiko; Nakamura, Emi; Koga, Tomoshige; Fukuda, Hiroyuki

    2010-01-15

    In previous paper, we reported that stimulation of the nucleus raphe magnus (stim-NRM) inhibits the induction of retching by afferent vagal fibers (VAs). We performed the present study to identity the transmitter of inhibition and then the site. The following results were obtained in decerebrated and paralyzed dogs. 1) The induction of fictive retching was suppressed by i.v. injection of 5-HT, and by 4th ventricular administration of 5-HT or a 5-HT3-receptor (R) agonist, 1-(m-chlorophenyl)-biguanade hydrochloride (m-CPBG). 2) Both forms of suppression were antagonized by i.v. injection of ondansetron, a 5-HT3-R antagonist. 3) Administration of the antagonist into the 4th ventricle did not affect the induction or its suppression by stim-NRM. These results suggest that the transmission from VAs to neurons in the nucleus solitarius (NTS) is suppressed by 5-HT via 5-HT3-R. However, these results also suggest that both the transmitter and receptor are not involved in the induction of retching by VAs or in its suppression by the NRM. Next, we examined the site of suppression. Unitary firings of NTS neurons in response to pulse-train stimulation of VAs were not inhibited by NRM stimulation. Moreover, the firing of NTS neurons during the induction of retching by vagal stimulation did not significantly decrease with the superimposition of stim-NRM, although the induction of retching was completely suppressed. These results suggest that suppression of the induction of retching by the descending inhibitory system of pain did not occur in the synapse between afferent vagal fibers and NTS neurons. The site of suppression is discussed.

  2. Electrocortical and behavioral responses elicited by acute electrical stimulation of inferior thalamic peduncle and nucleus reticularis thalami in a patient with major depression disorder.

    PubMed

    Velasco, Marcos; Velasco, Francisco; Jiménez, Fiacro; Carrillo-Ruiz, José D; Velasco, Ana Luisa; Salín-Pascual, Rafael

    2006-02-01

    Our aim was to study electrocortical and behavioral responses elicited by 6, 60 and 3/s stimulation of the inferior thalamic peduncle (ITP) and nucleus reticularis thalami (Re) in a patient with of major depression disorder resistant to psychotherapy, pharmacotherapy and electroconvulsive therapy and candidate to be treated by electrical stimulation of the ITP. In this patient, two multicontact electrodes were implanted bilaterally through frontal coronal parasagittal burr-holes with oblique trajectories aiming ITP and Re. Stimulation was performed through externalized systems. Referential scalp electroencephalographic (EEG) recordings were performed and subjective sensations and clinical symptoms reported by patient and changes in responsiveness in single response tasks during stimulation trials were systematically recorded. Unilateral, low (6/s) and high (60/s) frequency stimulation of either ITP or Re produced identical recruiting-like responses or desynchronization-DC shift changes predominant at frontopolar region, bilaterally. Billateral, high intensity 3/s stimulation or either ITP or Re produced electrocortical responses that consisted in generalized 3/s spike-wave complexes predominant at frontopolar, frontocentral and frontotemporal regions. However, while ITP responses were accompanied by all symptoms described for a spontaneous absence attack, Re responses were behaviorly accompanied only by delayed reaction time. These data suggests that in humans as in cats, ITP and Re are both part of a non-specific thalamo-orbitofrontal system normally engaged in cortical synchronization, selective attention and sleep. Under abnormal conditions, ITP and RE may play a role in the physiopathology of typical absence attacks and depression disorders.

  3. Alternating verbal fluency performance following bilateral subthalamic nucleus deep brain stimulation for Parkinson's disease.

    PubMed

    Marshall, D F; Strutt, A M; Williams, A E; Simpson, R K; Jankovic, J; York, M K

    2012-12-01

    Despite common occurrences of verbal fluency declines following bilateral subthalamic nucleus deep brain stimulation (STN-DBS) for the treatment of Parkinson's disease (PD), alternating fluency measures using cued and uncued paradigms have not been evaluated. Twenty-three STN-DBS patients were compared with 20 non-surgical PD patients on a comprehensive neuropsychological assessment, including cued and uncued intradimensional (phonemic/phonemic and semantic/semantic) and extradimensional (phonemic/semantic) alternating fluency measures at baseline and 6-month follow-up. STN-DBS patients demonstrated a greater decline on the cued phonemic/phonemic fluency and the uncued phonemic/semantic fluency tasks compared to the PD patients. For STN-DBS patients, verbal learning and information processing speed accounted for a significant proportion of the variance in declines in alternating phonemic/phonemic and phonemic/semantic fluency scores, respectively, whilst only naming was related to uncued phonemic/semantic performance for the PD patients. Both groups were aided by cueing for the extradimensional task at baseline and follow-up, and the PD patients were also aided by cueing for the phonemic/phonemic task on follow-up. These findings suggest that changes in alternating fluency are not related to disease progression alone as STN-DBS patients demonstrated greater declines over time than the PD patients, and this change was related to declines in information processing speed. © 2012 The Author(s) European Journal of Neurology © 2012 EFNS.

  4. Optogenetically-induced tonic dopamine release from VTA-nucleus accumbens projections inhibits reward consummatory behaviors

    PubMed Central

    Mikhailova, Maria A.; Bass, Caroline E.; Grinevich, Valentina P.; Chappell, Ann M.; Deal, Alex L.; Bonin, Keith D.; Weiner, Jeff L.; Gainetdinov, Raul R.; Budygin, Evgeny A.

    2016-01-01

    Recent optogenetic studies demonstrated that phasic dopamine release in the nucleus accumbens may play a causal role in multiple aspects of natural and drug reward-related behaviors. The role of tonic dopamine release in reward consummatory behavior remains unclear. The current study used a combinatorial viral-mediated gene delivery approach to express ChR2 on mesolimbic dopamine neurons in rats. We used optical activation of this dopamine circuit to mimic tonic dopamine release in the nucleus accumbens and to explore the causal relationship between this form of dopamine signaling within the ventral tegmental area (VTA)-nucleus accumbens projection and consumption of a natural reward. Using a two bottle choice paradigm (sucrose vs. water), the experiments revealed that tonic optogenetic stimulation of mesolimbic dopamine transmission significantly decreased reward consummatory behaviors. Specifically, there was a significant decrease in the number of bouts, licks and amount of sucrose obtained during the drinking session. Notably, activation of VTA dopamine cell bodies or dopamine terminals in the nucleus accumbens resulted in identical behavioral consequences. No changes in the water intake were evident under the same experimental conditions. Collectively, these data demonstrate that tonic optogenetic stimulation of VTA-nucleus accumbens dopamine release is sufficient to inhibit reward consummatory behavior, possibly by preventing this circuit from engaging in phasic activity that is thought to be essential for reward-based behaviors. PMID:27421228

  5. Interactions between Brainstem Noradrenergic Neurons and the Nucleus Accumbens Shell in Modulating Memory for Emotionally Arousing Events

    ERIC Educational Resources Information Center

    Kerfoot, Erin C.; Williams, Cedric L.

    2011-01-01

    The nucleus accumbens shell (NAC) receives axons containing dopamine-[beta]-hydroxylase that originate from brainstem neurons in the nucleus of the solitary tract (NTS). Recent findings show that memory enhancement produced by stimulating NTS neurons after learning may involve interactions with the NAC. However, it is unclear whether these…

  6. c-Met must translocate to the nucleus to initiate calcium signals.

    PubMed

    Gomes, Dawidson A; Rodrigues, Michele A; Leite, M Fatima; Gomez, Marcus V; Varnai, Peter; Balla, Tamas; Bennett, Anton M; Nathanson, Michael H

    2008-02-15

    Hepatocyte growth factor (HGF) is important for cell proliferation, differentiation, and related activities. HGF acts through its receptor c-Met, which activates downstream signaling pathways. HGF binds to c-Met at the plasma membrane, where it is generally believed that c-Met signaling is initiated. Here we report that c-Met rapidly translocates to the nucleus upon stimulation with HGF. Ca(2+) signals that are induced by HGF result from phosphatidylinositol 4,5-bisphosphate hydrolysis and inositol 1,4,5-trisphosphate formation within the nucleus rather than within the cytoplasm. Translocation of c-Met to the nucleus depends upon the adaptor protein Gab1 and importin beta1, and formation of Ca(2+) signals in turn depends upon this translocation. HGF may exert its particular effects on cells because it bypasses signaling pathways in the cytoplasm to directly activate signaling pathways in the nucleus.

  7. Adhesion-Dependent Redistribution of MAP Kinase and MEK Promotes Muscarinic Receptor-Mediated Signaling to the Nucleus

    PubMed Central

    Slack, Barbara E.; Siniaia, Marina S.

    2008-01-01

    The mitogen-activated protein kinases (MAPKs) are activated by extracellular signals, and translocate to the nucleus where they modulate transcription. Integrin-mediated cell adhesion to extracellular matrix (ECM) proteins is required for efficient transmission of MAPK-based signals initiated by growth factors. However, the modulation of G protein-coupled receptor (GPCR) signaling by adhesion is less well understood. In the present study we assessed the impact of cell adhesion on MAPK activation by muscarinic M3 receptors. The muscarinic agonist carbachol more efficiently promoted stress fiber formation and tyrosine phosphorylation of focal adhesion-associated proteins in M3 receptor-expressing cells adherent to fibronectin or collagen type I, as compared to polylysine. Overall MAPK activation was robust in cells adherent to all three substrata. However, total levels of MAPK and mitogen-activated protein kinase kinase (MEK) in the nucleus were significantly greater in cells adherent to ECM proteins for 2.5 hours, and levels of activated MAPK and MEK in the nuclei of these cells were higher following carbachol stimulation, relative to levels in cells adherent to polylysine. MEK inhibitors did not prevent adhesion-dependent translocation of MAPK and MEK to the nucleus, and increased nuclear phospho-MEK levels in carbachol-stimulated cells. The results suggest that adhesion of cells to ECM triggers the redistribution of MAPK and MEK to the nucleus, possibly as a result of the cytoskeletal rearrangements that accompany cell spreading. This may represent a mechanism for priming the nucleus with MEK and MAPK, leading to more rapid and pronounced increases in intranuclear phospho-MAPK upon GPCR stimulation. PMID:15779001

  8. Photoproduction of lepton pairs in proton-nucleus and nucleus-nucleus collisions at RHIC and LHC energies

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Moreira, B. D.; Goncalves, V. P.; De Santana Amaral, J. T.

    2013-03-25

    In this contribution we study coherent interactions as a probe of the nonlinear effects in the Quantum Electrodynamics (QED). In particular, we study the multiphoton effects in the production of leptons pairs for proton-nucleus and nucleus-nucleus collisions for heavy nuclei. In the proton-nucleus we assume the ultrarelativistic proton as a source of photons and estimate the photoproduction of lepton pairs on nuclei at RHIC and LHC energies considering the multiphoton effects associated to multiple rescattering of the projectile photon on the proton of the nucleus. In nucleus - nucleus colllisions we consider the two nuclei as a source of photons.more » As each scattering contributes with a factor {alpha}Z to the cross section, this contribution must be taken into account for heavy nuclei. We consider the Coulomb corrections to calculate themultiple scatterings and estimate the total cross section for muon and tau pair production in proton-nucleus and nucleus-nucleus collisions at RHIC and LHC energies.« less

  9. Differential regulation of serotonin-1A receptor-stimulated [35S]GTP gamma S binding in the dorsal raphe nucleus by citalopram and escitalopram.

    PubMed

    Rossi, Dania V; Burke, Teresa F; Hensler, Julie G

    2008-03-31

    The effect of chronic citalopram or escitalopram administration on 5-HT1A receptor function in the dorsal raphe nucleus was determined by measuring [35S]GTP gamma S binding stimulated by the 5-HT1A receptor agonist (R)-(+)-8-OH-DPAT (1nM-10 microM). Although chronic administration of citalopram or escitalopram has been shown to desensitize somatodendritic 5-HT1A autoreceptors, we found that escitalopram treatment decreased the efficacy of 5-HT1A receptors to activate G proteins, whereas citalopram treatment did not. The binding of [3H]8-OH-DPAT to the coupled, high affinity agonist state of the receptor was not altered by either treatment. Interestingly, escitalopram administration resulted in greater occupancy of serotonin transporter sites as measured by the inhibition of [3H]cyanoimipramine binding. As the binding and action of escitalopram is limited by the inactive enantiomer R-citalopram present in racemic citalopram, we propose that the regulation of 5-HT1A receptor function in the dorsal raphe nucleus at the level of receptor-G protein interaction may be a result of greater inhibition of the serotonin transporter by escitalopram.

  10. Resting state functional MRI in Parkinson’s disease: the impact of deep brain stimulation on ‘effective’ connectivity

    PubMed Central

    Kahan, Joshua; Urner, Maren; Moran, Rosalyn; Flandin, Guillaume; Marreiros, Andre; Mancini, Laura; White, Mark; Thornton, John; Yousry, Tarek; Zrinzo, Ludvic; Hariz, Marwan; Limousin, Patricia; Friston, Karl

    2014-01-01

    Depleted of dopamine, the dynamics of the parkinsonian brain impact on both ‘action’ and ‘resting’ motor behaviour. Deep brain stimulation has become an established means of managing these symptoms, although its mechanisms of action remain unclear. Non-invasive characterizations of induced brain responses, and the effective connectivity underlying them, generally appeals to dynamic causal modelling of neuroimaging data. When the brain is at rest, however, this sort of characterization has been limited to correlations (functional connectivity). In this work, we model the ‘effective’ connectivity underlying low frequency blood oxygen level-dependent fluctuations in the resting Parkinsonian motor network—disclosing the distributed effects of deep brain stimulation on cortico-subcortical connections. Specifically, we show that subthalamic nucleus deep brain stimulation modulates all the major components of the motor cortico-striato-thalamo-cortical loop, including the cortico-striatal, thalamo-cortical, direct and indirect basal ganglia pathways, and the hyperdirect subthalamic nucleus projections. The strength of effective subthalamic nucleus afferents and efferents were reduced by stimulation, whereas cortico-striatal, thalamo-cortical and direct pathways were strengthened. Remarkably, regression analysis revealed that the hyperdirect, direct, and basal ganglia afferents to the subthalamic nucleus predicted clinical status and therapeutic response to deep brain stimulation; however, suppression of the sensitivity of the subthalamic nucleus to its hyperdirect afferents by deep brain stimulation may subvert the clinical efficacy of deep brain stimulation. Our findings highlight the distributed effects of stimulation on the resting motor network and provide a framework for analysing effective connectivity in resting state functional MRI with strong a priori hypotheses. PMID:24566670

  11. Encoding of the amplitude modulation of pulsatile electrical stimulation in the feline cochlear nucleus by neurons in the inferior colliculus; effects of stimulus pulse rate

    NASA Astrophysics Data System (ADS)

    McCreery, Douglas; Han, Martin; Pikov, Victor; Yadav, Kamal; Pannu, Satinderpall

    2013-10-01

    Objectives. Persons without a functional auditory nerve cannot benefit from cochlear implants, but some hearing can be restored by an auditory brainstem implant (ABI) with stimulating electrodes implanted on the surface of the cochlear nucleus (CN). Most users benefit from their ABI, but speech recognition tends to be poorer than for users of cochlear implants. Psychophysical studies suggest that poor modulation detection may contribute to the limited performance of ABI users. In a cat model, we determined how the pulse rate of the electrical stimulus applied within or on the CN affects temporal and rate encoding of amplitude modulation (AM) by neurons in the central nucleus of the inferior colliculus (ICC). Approach. Stimulating microelectrodes were implanted chronically in and on the cats' CN, and multi-site recording microelectrodes were implanted chronically into the ICC. Encoding of AM pulse trains by neurons in the ICC was characterized as vector strength (VS), the synchrony of neural activity with the AM, and as the mean rate of neuronal action potentials (neuronal spike rate (NSR)). Main results. For intranuclear microstimulation, encoding of AM as VS was up to 3 dB greater when stimulus pulse rate was increased from 250 to 500 pps, but only for neuronal units with low best acoustic frequencies, and when the electrical stimulation was modulated at low frequencies (10-20 Hz). For stimulation on the surface of the CN, VS was similar at 250 and 500 pps, and the dynamic range of the VS was reduced for pulse rates greater than 250 pps. Modulation depth was encoded strongly as VS when the maximum stimulus amplitude was held constant across a range of modulation depth. This ‘constant maximum’ protocol allows enhancement of modulation depth while preserving overall dynamic range. However, modulation depth was not encoded as strongly as NSR. Significance. The findings have implications for improved sound processors for present and future ABIs. The performance of

  12. Higgs-boson production in nucleus-nucleus collisions

    NASA Technical Reports Server (NTRS)

    Norbury, J. W.; Townsend, L. W. (Principal Investigator)

    1990-01-01

    Cross-section calculations are presented for the production of intermediate-mass Higgs bosons produced in ultrarelativistic nucleus-nucleus collisions via two-photon fusion. The calculations are performed in position space using Baur's method for folding together the Weizsacker-Williams virtual-photon spectra of the two colliding nuclei. It is found that two-photon fusion in nucleus-nucleus collisions is a plausible way of finding intermediate-mass Higgs bosons at the Superconducting Super Collider or the CERN Large Hadron Collider.

  13. Higgs-Boson Production in Nucleus-Nucleus Collisions

    NASA Technical Reports Server (NTRS)

    Norbury, John W.

    1992-01-01

    Cross section calculations are presented for the production of intermediate-mass Higgs bosons produced in ultrarelativistic nucleus-nucleus collisions via two photon fusion. The calculations are performed in position space using Baur's method for folding together the Weizsacker-Williams virtual-photon spectra of the two colliding nuclei. It is found that two photon fusion in nucleus-nucleus collisions is a plausible way of finding intermediate-mass Higgs bosons at the Superconducting Super Collider or the CERN Large Hadron Collider.

  14. Battery Longevity Comparison of Two Commonly Available Dual Channel Implantable Pulse Generators Used for Subthalamic Nucleus Stimulation in Parkinson's Disease.

    PubMed

    Fisher, Benjamin; Kausar, Jamilla; Garratt, Hayley; Hodson, James; White, Anwen; Ughratdar, Ismail; Mitchell, Rosalind

    2018-06-19

    Deep brain stimulation for Parkinson's disease (PD) utilises an implantable pulse generator (IPG) whose finite lifespan in non-rechargeable systems necessitates their periodic replacement. We wish to determine if there is any significant difference in longevity of 2 commonly used IPG systems; the Medtronic Kinetra, and the Medtronic Activa Primary Cell (PC), which has come to replace it. All patients with bilateral Subthalamic Nucleus stimulators for PD performed in our centre were included. Battery life was then assessed using a Kaplan-Meier approach and comparisons between the Kinetra and Activa PC batteries were performed using log-rank tests. Complete data was available for 183 patients. There was a significant difference in the average battery duration with an estimated median battery life in the Kinetra cohort of 6.6 years (95% CI 6.4-6.7), compared to 4.5 years (95% CI 4.4-4.5) in the Activa PC cohort (p < 0.001). The Activa PC IPG demonstrates a significantly reduced battery life of 2.1 years, with a median battery life of 4.5 years in comparison to 6.6 years in the Kinetra IPG. Future technology developments should therefore be focused on improving the battery life of the newer IPG systems. © 2018 S. Karger AG, Basel.

  15. Bilateral stimulation of the subthalamic nucleus has differential effects on reactive and proactive inhibition and conflict-induced slowing in Parkinson's disease.

    PubMed

    Obeso, Ignacio; Wilkinson, Leonora; Rodríguez-Oroz, Maria-Cruz; Obeso, Jose A; Jahanshahi, Marjan

    2013-05-01

    It has been proposed that the subthalamic nucleus (STN) mediates response inhibition and conflict resolution through the fronto-basal ganglia pathways. Our aim was to compare the effects of deep brain stimulation (DBS) of the STN on reactive and proactive inhibition and conflict resolution in Parkinson's disease using a single task. We used the conditional Stop signal reaction time task that provides the Stop signal reaction time (SSRT) as a measure of reactive inhibition, the response delay effect (RDE) as a measure of proactive inhibition and conflict-induced slowing (CIS) as a measure of conflict resolution. DBS of the STN significantly prolonged SSRT relative to stimulation off. However, while the RDE measure of proactive inhibition was not significantly altered by DBS of the STN, relative to healthy controls, RDE was significantly lower with DBS off but not DBS on. DBS of the STN did not alter the mean CIS but produced a significant differential effect on the slowest and fastest RTs on conflict trials, further prolonging the slowest RTs on the conflict trials relative to DBS off and to controls. These results are the first demonstration, using a single task in the same patient sample, that DBS of the STN produces differential effects on reactive and proactive inhibition and on conflict resolution, suggesting that these effects are likely to be mediated through the impact of STN stimulation on different fronto-basal ganglia pathways: hyperdirect, direct and indirect.

  16. High energy nucleus-nucleus collisions

    NASA Technical Reports Server (NTRS)

    Wosiek, B.

    1986-01-01

    Experimental results on high energy nucleus-nucleus interactions are presented. The data are discussed within the framework of standard super-position models and from the point-of-view of the possible formation of new states of matter in heavy ion collisions.

  17. Perimovement decrease of alpha/beta oscillations in the human nucleus accumbens.

    PubMed

    Stenner, Max-Philipp; Dürschmid, Stefan; Rutledge, Robb B; Zaehle, Tino; Schmitt, Friedhelm C; Kaufmann, Jörn; Voges, Jürgen; Heinze, Hans-Jochen; Dolan, Raymond J; Schoenfeld, Mircea Ariel

    2016-10-01

    The human nucleus accumbens is thought to play an important role in guiding future action selection via an evaluation of current action outcomes. Here we provide electrophysiological evidence for a more direct, i.e., online, role during action preparation. We recorded local field potentials from the nucleus accumbens in patients with epilepsy undergoing surgery for deep brain stimulation. We found a consistent decrease in the power of alpha/beta oscillations (10-30 Hz) before and around the time of movements. This perimovement alpha/beta desynchronization was observed in seven of eight patients and was present both before instructed movements in a serial reaction time task as well as before self-paced, deliberate choices in a decision making task. A similar beta decrease over sensorimotor cortex and in the subthalamic nucleus has been directly related to movement preparation and execution. Our results support the idea of a direct role of the human nucleus accumbens in action preparation and execution. Copyright © 2016 the American Physiological Society.

  18. Perimovement decrease of alpha/beta oscillations in the human nucleus accumbens

    PubMed Central

    Dürschmid, Stefan; Rutledge, Robb B.; Zaehle, Tino; Schmitt, Friedhelm C.; Kaufmann, Jörn; Voges, Jürgen; Heinze, Hans-Jochen; Dolan, Raymond J.; Schoenfeld, Mircea Ariel

    2016-01-01

    The human nucleus accumbens is thought to play an important role in guiding future action selection via an evaluation of current action outcomes. Here we provide electrophysiological evidence for a more direct, i.e., online, role during action preparation. We recorded local field potentials from the nucleus accumbens in patients with epilepsy undergoing surgery for deep brain stimulation. We found a consistent decrease in the power of alpha/beta oscillations (10–30 Hz) before and around the time of movements. This perimovement alpha/beta desynchronization was observed in seven of eight patients and was present both before instructed movements in a serial reaction time task as well as before self-paced, deliberate choices in a decision making task. A similar beta decrease over sensorimotor cortex and in the subthalamic nucleus has been directly related to movement preparation and execution. Our results support the idea of a direct role of the human nucleus accumbens in action preparation and execution. PMID:27486103

  19. Fornix deep brain stimulation circuit effect is dependent on major excitatory transmission via the nucleus accumbens.

    PubMed

    Ross, Erika K; Kim, Joo Pyung; Settell, Megan L; Han, Seong Rok; Blaha, Charles D; Min, Hoon-Ki; Lee, Kendall H

    2016-03-01

    Deep brain stimulation (DBS) is a circuit-based treatment shown to relieve symptoms from multiple neurologic and neuropsychiatric disorders. In order to treat the memory deficit associated with Alzheimer's disease (AD), several clinical trials have tested the efficacy of DBS near the fornix. Early results from these studies indicated that patients who received fornix DBS experienced an improvement in memory and quality of life, yet the mechanisms behind this effect remain controversial. It is known that transmission between the medial limbic and corticolimbic circuits plays an integral role in declarative memory, and dysfunction at the circuit level results in various forms of dementia, including AD. Here, we aimed to determine the potential underlying mechanism of fornix DBS by examining the functional circuitry and brain structures engaged by fornix DBS. A multimodal approach was employed to examine global and local temporal changes that occur in an anesthetized swine model of fornix DBS. Changes in global functional activity were measured by functional MRI (fMRI), and local neurochemical changes were monitored by fast scan cyclic voltammetry (FSCV) during electrical stimulation of the fornix. Additionally, intracranial microinfusions into the nucleus accumbens (NAc) were performed to investigate the global activity changes that occur with dopamine and glutamate receptor-specific antagonism. Hemodynamic responses in both medial limbic and corticolimbic circuits measured by fMRI were induced by fornix DBS. Additionally, fornix DBS resulted in increases in dopamine oxidation current (corresponding to dopamine efflux) monitored by FSCV in the NAc. Finally, fornix DBS-evoked hemodynamic responses in the amygdala and hippocampus decreased following dopamine and glutamate receptor antagonism in the NAc. The present findings suggest that fornix DBS modulates dopamine release on presynaptic dopaminergic terminals in the NAc, involving excitatory glutamatergic input, and

  20. Local vs. volume conductance activity of field potentials in the human subthalamic nucleus

    PubMed Central

    Marmor, Odeya; Valsky, Dan; Joshua, Mati; Bick, Atira S; Arkadir, David; Tamir, Idit; Bergman, Hagai; Israel, Zvi

    2017-01-01

    Subthalamic nucleus field potentials have attracted growing research and clinical interest over the last few decades. However, it is unclear whether subthalamic field potentials represent locally generated neuronal subthreshold activity or volume conductance of the organized neuronal activity generated in the cortex. This study aimed at understanding of the physiological origin of subthalamic field potentials and determining the most accurate method for recording them. We compared different methods of recordings in the human subthalamic nucleus: spikes (300–9,000 Hz) and field potentials (3–100 Hz) recorded by monopolar micro- and macroelectrodes, as well as by differential-bipolar macroelectrodes. The recordings were done outside and inside the subthalamic nucleus during electrophysiological navigation for deep brain stimulation procedures (150 electrode trajectories) in 41 Parkinson’s disease patients. We modeled the signal and estimated the contribution of nearby/independent vs. remote/common activity in each recording configuration and area. Monopolar micro- and macroelectrode recordings detect field potentials that are considerably affected by common (probably cortical) activity. However, bipolar macroelectrode recordings inside the subthalamic nucleus can detect locally generated potentials. These results are confirmed by high correspondence between the model predictions and actual correlation of neuronal activity recorded by electrode pairs. Differential bipolar macroelectrode subthalamic field potentials can overcome volume conductance effects and reflect locally generated neuronal activity. Bipolar macroelectrode local field potential recordings might be used as a biological marker of normal and pathological brain functions for future electrophysiological studies and navigation systems as well as for closed-loop deep brain stimulation paradigms. NEW & NOTEWORTHY Our results integrate a new method for human subthalamic recordings with a development of

  1. Neuronal activity-regulated gene transcription: how are distant synaptic signals conveyed to the nucleus?

    PubMed Central

    Matamales, Miriam

    2012-01-01

    Synaptic activity can trigger gene expression programs that are required for the stable change of neuronal properties, a process that is essential for learning and memory. Currently, it is still unclear how the stimulation of dendritic synapses can be coupled to transcription in the nucleus in a timely way given that large distances can separate these two cellular compartments. Although several mechanisms have been proposed to explain long distance communication between synapses and the nucleus, the possible co-existence of these models and their relevance in physiological conditions remain elusive. One model suggests that synaptic activation triggers the translocation to the nucleus of certain transcription regulators localised at postsynaptic sites that function as synapto-nuclear messengers. Alternatively, it has been hypothesised that synaptic activity initiates propagating regenerative intracellular calcium waves that spread through dendrites into the nucleus where nuclear transcription machinery is thereby regulated. It has also been postulated that membrane depolarisation of voltage-gated calcium channels on the somatic membrane is sufficient to increase intracellular calcium concentration and activate transcription without the need for transported signals from distant synapses. Here I provide a critical overview of the suggested mechanisms for coupling synaptic stimulation to transcription, the underlying assumptions behind them and their plausible physiological significance. PMID:24327840

  2. Neuronal activity-regulated gene transcription: how are distant synaptic signals conveyed to the nucleus?

    PubMed

    Matamales, Miriam

    2012-12-19

    Synaptic activity can trigger gene expression programs that are required for the stable change of neuronal properties, a process that is essential for learning and memory. Currently, it is still unclear how the stimulation of dendritic synapses can be coupled to transcription in the nucleus in a timely way given that large distances can separate these two cellular compartments. Although several mechanisms have been proposed to explain long distance communication between synapses and the nucleus, the possible co-existence of these models and their relevance in physiological conditions remain elusive. One model suggests that synaptic activation triggers the translocation to the nucleus of certain transcription regulators localised at postsynaptic sites that function as synapto-nuclear messengers. Alternatively, it has been hypothesised that synaptic activity initiates propagating regenerative intracellular calcium waves that spread through dendrites into the nucleus where nuclear transcription machinery is thereby regulated. It has also been postulated that membrane depolarisation of voltage-gated calcium channels on the somatic membrane is sufficient to increase intracellular calcium concentration and activate transcription without the need for transported signals from distant synapses. Here I provide a critical overview of the suggested mechanisms for coupling synaptic stimulation to transcription, the underlying assumptions behind them and their plausible physiological significance.

  3. Neuronal activity-regulated gene transcription: how are distant synaptic signals conveyed to the nucleus?

    PubMed

    Matamales, Miriam

    2012-01-01

    Synaptic activity can trigger gene expression programs that are required for the stable change of neuronal properties, a process that is essential for learning and memory. Currently, it is still unclear how the stimulation of dendritic synapses can be coupled to transcription in the nucleus in a timely way given that large distances can separate these two cellular compartments. Although several mechanisms have been proposed to explain long distance communication between synapses and the nucleus, the possible co-existence of these models and their relevance in physiological conditions remain elusive. One model suggests that synaptic activation triggers the translocation to the nucleus of certain transcription regulators localised at postsynaptic sites that function as synapto-nuclear messengers. Alternatively, it has been hypothesised that synaptic activity initiates propagating regenerative intracellular calcium waves that spread through dendrites into the nucleus where nuclear transcription machinery is thereby regulated. It has also been postulated that membrane depolarisation of voltage-gated calcium channels on the somatic membrane is sufficient to increase intracellular calcium concentration and activate transcription without the need for transported signals from distant synapses. Here I provide a critical overview of the suggested mechanisms for coupling synaptic stimulation to transcription, the underlying assumptions behind them and their plausible physiological significance.

  4. [Postsynaptic reactions of cerebral cortex neurons, activated by nociceptive afferents during stimulation of the Raphe nuclei].

    PubMed

    Labakhua, T Sh; Dzhanashiia, T K; Gedevanishvili, G I; Dzhokhadze, L D; Tkemaladze, T T; Abzianidze, I V

    2012-01-01

    On cats, we studied the influence of stimulation of the Raphe nuclei (RN) on postsynaptic processes evoked in neurons of the somatosensory cortex by stimulation of nociceptive (intensive stimulation of the tooth pulp) and non-nociceptive (moderate stimulation of the ventroposteromedial--VPN--nucleus of the thalamus) afferent inputs. 6 cells, selectively excited by stimulation of nocciceptors and 9 cells, activated by both the above nociceptive and non-nociceptive influences (nociceptive and convergent neurons, respectively) were recorded intracellular. In neurons of both groups, responses to nociceptive stimulation (of sufficient intensity) looked like an EPSP-spike-IPSP (the letter of significant duration, up to 200-300 ms) compleх. Conditioning stimulation of the RN which preceded test stimulus applied to the tooth pulp or VPM nucleus by 100 to 800 ms, induced 40-60 % decrease of the IPSP amplitude only, while maхimal effect of influence, in both cases, was noted within intervals of 300-800 ms between conditioning and test stimulus. During stimulation of the RN, serotonin released via receptor and second messengers, provides postsynaptic modulation of GABAergic system, decreasing the IPSP amplitude which occurs after stimulation of both the tooth pulp and VPM thalamic nucleus. This process may be realized trough either pre- or postsynaptic mechanisms.

  5. Sexual well being in parkinsonian patients after deep brain stimulation of the subthalamic nucleus

    PubMed Central

    Castelli, L; Perozzo, P; Genesia, M; Torre, E; Pesare, M; Cinquepalmi, A; Lanotte, M; Bergamasco, B; Lopiano, L

    2004-01-01

    Objectives: To evaluate changes in sexual well being in a group of patients with Parkinson's disease following deep brain stimulation (DBS) of the subthalamic nucleus (STN). Methods: 31 consecutive patients with Parkinson's disease (21 men and 10 women), bilaterally implanted for DBS of STN, were evaluated one month before and 9–12 months after surgery. Sexual functioning was assessed using a reduced form of the Gollombok Rust inventory of sexual satisfaction (GRISS). Depression (Beck depression inventory) and anxiety (STAI-X1/X2) were also evaluated. Relations between sexual functioning and modifications in the severity of disease (Hoehn and Yahr stage), reduction in levodopa equivalent daily dosage (LEDD), age, and duration of disease were analysed. Results: While no modifications were found in female patients, male patients reported slightly but significantly more satisfaction with their sexual life after DBS of STN. When only male patients under 60 years old were considered, a greater improvement in sexual functioning was found, though still small. Modifications in depressive symptoms and anxiety, as well as duration of the disease, reduction in LEDD, and improvement in the severity of disease, showed no relation with changes in sexual functioning after DBS of STN. Conclusions: DBS of STN appears to affect sexual functioning in a small but positive way. Male patients with Parkinson's disease, especially when under 60, appeared more satisfied with their sexual well being over a short term follow up period. PMID:15314111

  6. Deep Brain Stimulation of Medial Dorsal and Ventral Anterior Nucleus of the Thalamus in OCD: A Retrospective Case Series

    PubMed Central

    Lenartz, Doris; Kuhn, Jens; Sturm, Volker

    2016-01-01

    Background The current notion that cortico-striato-thalamo-cortical circuits are involved in the pathophysiology of obsessive-compulsive disorder (OCD) has instigated the search for the most suitable target for deep brain stimulation (DBS). However, despite extensive research, uncertainty about the ideal target remains with many structures being underexplored. The aim of this report is to address a new target for DBS, the medial dorsal (MD) and the ventral anterior (VA) nucleus of the thalamus, which has thus far received little attention in the treatment of OCD. Methods In this retrospective trial, four patients (three female, one male) aged 31–48 years, suffering from therapy-refractory OCD underwent high-frequency DBS of the MD and VA. In two patients (de novo group) the thalamus was chosen as a primary target for DBS, whereas in two patients (rescue DBS group) lead implantation was performed in a rescue DBS attempt following unsuccessful primary stimulation. Results Continuous thalamic stimulation yielded no significant improvement in OCD symptom severity. Over the course of thalamic DBS symptoms improved in only one patient who showed “partial response” on the Yale-Brown Obsessive Compulsive (Y-BOCS) Scale. Beck Depression Inventory scores dropped by around 46% in the de novo group; anxiety symptoms improved by up to 34%. In the de novo DBS group no effect of DBS on anxiety and mood was observable. Conclusion MD/VA-DBS yielded no adequate alleviation of therapy-refractory OCD, the overall strategy in targeting MD/VA as described in this paper can thus not be recommended in DBS for OCD. The magnocellular portion of MD (MDMC), however, might prove a promising target in the treatment of mood related and anxiety disorders. PMID:27504631

  7. Deep brain stimulation of the subthalamic nucleus alters the cortical profile of response inhibition in the beta frequency band: a scalp EEG study in Parkinson's disease

    PubMed Central

    Swann, Nicole; Poizner, Howard; Houser, Melissa; Gould, Sherrie; Greenhouse, Ian; Cai, Weidong; Strunk, Jon; George, Jobi; Aron, Adam R

    2011-01-01

    Stopping an initiated response could be implemented by a fronto-basal-ganglia circuit, including the right inferior frontal cortex (rIFC) and the subthalamic nucleus (STN). Intracranial recording studies in humans reveal an increase in beta-band power (~16-20 Hz) within the rIFC and STN when a response is stopped. This suggests that the beta-band could be important for communication in this network. If this is the case, then altering one region should affect the electrophysiological response at the other. We addressed this hypothesis by recording scalp EEG during a stop task while modulating STN activity with deep brain stimulation. We studied 15 human patients with Parkinson's Disease and 15 matched healthy control subjects. Behaviorally, patients OFF stimulation were slower than controls to stop their response. Moreover, stopping speed was improved for ON compared to OFF stimulation. For scalp EEG, there was greater beta power, around the time of stopping, for patients ON compared to OFF stimulation. This effect was stronger over the right compared to left frontal cortex, consistent with the putative right-lateralization of the stopping network. Thus, deep brain stimulation of the STN improved behavioral stopping performance and increased the beta-band response over the right frontal cortex. These results complement other evidence for a structurally-connected, functional, circuit between right frontal cortex and the basal ganglia. The results also suggest that deep brain stimulation of the STN may improve task performance by increasing the fidelity of information transfer within a fronto-basal ganglia circuit. PMID:21490213

  8. Regulation of calcium signals in the nucleus by a nucleoplasmic reticulum

    PubMed Central

    Echevarría, Wihelma; Leite, M. Fatima; Guerra, Mateus T.; Zipfel, Warren R.; Nathanson, Michael H.

    2013-01-01

    Calcium is a second messenger in virtually all cells and tissues1. Calcium signals in the nucleus have effects on gene transcription and cell growth that are distinct from those of cytosolic calcium signals; however, it is unknown how nuclear calcium signals are regulated. Here we identify a reticular network of nuclear calcium stores that is continuous with the endoplasmic reticulum and the nuclear envelope. This network expresses inositol 1,4,5-trisphosphate (InsP3) receptors, and the nuclear component of InsP3-mediated calcium signals begins in its locality. Stimulation of these receptors with a little InsP3 results in small calcium signals that are initiated in this region of the nucleus. Localized release of calcium in the nucleus causes nuclear protein kinase C (PKC) to translocate to the region of the nuclear envelope, whereas release of calcium in the cytosol induces translocation of cytosolic PKC to the plasma membrane. Our findings show that the nucleus contains a nucleoplasmic reticulum with the capacity to regulate calcium signals in localized subnuclear regions. The presence of such machinery provides a potential mechanism by which calcium can simultaneously regulate many independent processes in the nucleus. PMID:12717445

  9. Cognitive outcome and reliable change indices two years following bilateral subthalamic nucleus deep brain stimulation.

    PubMed

    Williams, Amy E; Arzola, Gladys Marina; Strutt, Adriana M; Simpson, Richard; Jankovic, Joseph; York, Michele K

    2011-06-01

    Subthalamic nucleus deep brain stimulation (STN-DBS) is currently the treatment of choice for medication-resistant levodopa-related motor complications in patients with Parkinson's disease (PD). While STN-DBS often results in meaningful motor improvements, consensus regarding long-term neuropsychological outcome continues to be debated. We assessed the cognitive outcomes of 19 STN-DBS patients compared to a group of 18 medically-managed PD patients on a comprehensive neuropsychological battery at baseline and two years post-surgery. Patients did not demonstrate changes in global cognitive functioning on screening measures. However, neuropsychological results revealed impairments in nonverbal recall, oral information processing speed, and lexical and semantic fluency in STN-DBS patients compared to PD controls 2 years post-surgery in these preliminary analyses. Additionally, reliable change indices revealed that approximately 50% of STN-DBS patients demonstrated significant declines in nonverbal memory and oral information processing speed compared to 25-30% of PD controls, and 26% of STN-DBS patients declined on lexical fluency compared to 11% of PD patients. Approximately 30% of both groups declined on semantic fluency. The number of STN-DBS patients who converted to dementia 2 years following surgery was not significantly different from the PD participants (32% versus 16%, respectively). Our results suggest that neuropsychological evaluations may identify possible mild cognitive changes following surgery. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. PAK1 translocates into nucleus in response to prolactin but not to estrogen

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Oladimeji, Peter, E-mail: Peter.Oladimeji@rockets.utoledo.edu; Diakonova, Maria, E-mail: mdiakon@utnet.utoledo.edu

    2016-04-22

    Tyrosyl phosphorylation of the p21-activated serine–threonine kinase 1 (PAK1) has an essential role in regulating PAK1 functions in breast cancer cells. We previously demonstrated that PAK1 serves as a common node for estrogen (E2)- and prolactin (PRL)-dependent pathways. We hypothesize herein that intracellular localization of PAK1 is affected by PRL and E2 treatments differently. We demonstrate by immunocytochemical analysis that PAK1 nuclear translocation is ligand-dependent: only PRL but not E2 stimulated PAK1 nuclear translocation. Tyrosyl phosphorylation of PAK1 is essential for this nuclear translocation because phospho-tyrosyl-deficient PAK1 Y3F mutant is retained in the cytoplasm in response to PRL. We confirmedmore » these data by Western blot analysis of subcellular fractions. In 30 min of PRL treatment, only 48% of pTyr-PAK1 is retained in the cytoplasm of PAK1 WT clone while 52% re-distributes into the nucleus and pTyr-PAK1 shuttles back to the cytoplasm by 60 min of PRL treatment. In contrast, PAK1 Y3F is retained in the cytoplasm. E2 treatment causes nuclear translocation of neither PAK1 WT nor PAK1 Y3F. Finally, we show by an in vitro kinase assay that PRL but not E2 stimulates PAK1 kinase activity in the nuclear fraction. Thus, PAK1 nuclear translocation is ligand-dependent: PRL activates PAK1 and induces translocation of activated pTyr-PAK1 into nucleus while E2 activates pTyr-PAK1 only in the cytoplasm. - Highlights: • Prolactin but not estrogen causes translocation of PAK1 into nucleus. • Tyrosyl phosphorylation of PAK1 is required for nuclear localization. • Prolactin but not estrogen stimulates PAK1 kinase activity in nucleus.« less

  11. The cellular mastermind(?) – Mechanotransduction and the nucleus

    PubMed Central

    Kaminski, Ashley; Fedorchak, Gregory R.; Lammerding, Jan

    2015-01-01

    Cells respond to mechanical stimulation by activation of specific signaling pathways and genes that allow the cell to adapt to its dynamic physical environment. How cells sense the various mechanical inputs and translate them into biochemical signals remains an area of active investigation. Recent reports suggest that the cell nucleus may be directly implicated in this cellular mechanotransduction process. In this chapter, we discuss how forces applied to the cell surface and cytoplasm induce changes in nuclear structure and organization, which could directly affect gene expression, while also highlighting the complex interplay between nuclear structural proteins and transcriptional regulators that may further modulate mechanotransduction signaling. Taken together, these findings paint a picture of the nucleus as a central hub in cellular mechanotransduction—both structurally and biochemically—with important implications in physiology and disease. PMID:25081618

  12. Brainstem stimulation increases functional connectivity of basal forebrain-paralimbic network in isoflurane-anesthetized rats.

    PubMed

    Pillay, Siveshigan; Liu, Xiping; Baracskay, Péter; Hudetz, Anthony G

    2014-09-01

    Brain states and cognitive-behavioral functions are precisely controlled by subcortical neuromodulatory networks. Manipulating key components of the ascending arousal system (AAS), via deep-brain stimulation, may help facilitate global arousal in anesthetized animals. Here we test the hypothesis that electrical stimulation of the oral part of the pontine reticular nucleus (PnO) under light isoflurane anesthesia, associated with loss of consciousness, leads to cortical desynchronization and specific changes in blood-oxygenation-level-dependent (BOLD) functional connectivity (FC) of the brain. BOLD signals were acquired simultaneously with frontal epidural electroencephalogram before and after PnO stimulation. Whole-brain FC was mapped using correlation analysis with seeds in major centers of the AAS. PnO stimulation produced cortical desynchronization, a decrease in δ- and θ-band power, and an increase in approximate entropy. Significant increases in FC after PnO stimulation occurred between the left nucleus Basalis of Meynert (NBM) as seed and numerous regions of the paralimbic network. Smaller increases in FC were present between the central medial thalamic nucleus and retrosplenium seeds and the left caudate putamen and NBM. The results suggest that, during light anesthesia, PnO stimulation preferentially modulates basal forebrain-paralimbic networks. We speculate that this may be a reflection of disconnected awareness.

  13. Thalamic Ventral Intermediate Nucleus Deep Brain Stimulation for Orthostatic Tremor.

    PubMed

    Lehn, Alexander C; O'Gorman, Cullen; Olson, Sarah; Salari, Mehri

    2017-01-01

    Orthostatic tremor (OT) was first described in 1977. It is characterized by rapid tremor of 13-18 Hz and can be recorded in the lower limbs and trunk muscles. OT remains difficult to treat, although some success has been reported with deep brain stimulation (DBS). We report a 68-year-old male with OT who did not improve significantly after bilateral thalamic stimulation. Although some patients were described who improved after DBS surgery, more information is needed about the effect of these treatment modalities on OT, ideally in the form of randomized trial data.

  14. The development of the Nucleus Freedom Cochlear implant system.

    PubMed

    Patrick, James F; Busby, Peter A; Gibson, Peter J

    2006-12-01

    Cochlear Limited (Cochlear) released the fourth-generation cochlear implant system, Nucleus Freedom, in 2005. Freedom is based on 25 years of experience in cochlear implant research and development and incorporates advances in medicine, implantable materials, electronic technology, and sound coding. This article presents the development of Cochlear's implant systems, with an overview of the first 3 generations, and details of the Freedom system: the CI24RE receiver-stimulator, the Contour Advance electrode, the modular Freedom processor, the available speech coding strategies, the input processing options of Smart Sound to improve the signal before coding as electrical signals, and the programming software. Preliminary results from multicenter studies with the Freedom system are reported, demonstrating better levels of performance compared with the previous systems. The final section presents the most recent implant reliability data, with the early findings at 18 months showing improved reliability of the Freedom implant compared with the earlier Nucleus 3 System. Also reported are some of the findings of Cochlear's collaborative research programs to improve recipient outcomes. Included are studies showing the benefits from bilateral implants, electroacoustic stimulation using an ipsilateral and/or contralateral hearing aid, advanced speech coding, and streamlined speech processor programming.

  15. Identification of the subthalamic nucleus in deep brain stimulation surgery with a novel wavelet-derived measure of neural background activity.

    PubMed

    Snellings, André; Sagher, Oren; Anderson, David J; Aldridge, J Wayne

    2009-10-01

    The authors developed a wavelet-based measure for quantitative assessment of neural background activity during intraoperative neurophysiological recordings so that the boundaries of the subthalamic nucleus (STN) can be more easily localized for electrode implantation. Neural electrophysiological data were recorded in 14 patients (20 tracks and 275 individual recording sites) with dopamine-sensitive idiopathic Parkinson disease during the target localization portion of deep brain stimulator implantation surgery. During intraoperative recording, the STN was identified based on audio and visual monitoring of neural firing patterns, kinesthetic tests, and comparisons between neural behavior and the known characteristics of the target nucleus. The quantitative wavelet-based measure was applied offline using commercially available software to measure the magnitude of the neural background activity, and the results of this analysis were compared with the intraoperative conclusions. Wavelet-derived estimates were also compared with power spectral density measurements. The wavelet-derived background levels were significantly higher in regions encompassed by the clinically estimated boundaries of the STN than in the surrounding regions (STN, 225 +/- 61 microV; ventral to the STN, 112 +/- 32 microV; and dorsal to the STN, 136 +/- 66 microV). In every track, the absolute maximum magnitude was found within the clinically identified STN. The wavelet-derived background levels provided a more consistent index with less variability than measurements with power spectral density. Wavelet-derived background activity can be calculated quickly, does not require spike sorting, and can be used to identify the STN reliably with very little subjective interpretation required. This method may facilitate the rapid intraoperative identification of STN borders.

  16. Coalescence Effects on Neutron Production in High Energy Nucleus-Nucleus Collisions

    DTIC Science & Technology

    2001-08-01

    25/Jun/2001 THESIS 1 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER COALESCENCE EFFECTS ON NEUTRON PRODUCTION IN HIGH- ENERGY NUCLEUS-NUCLEUS COLLISIONS 5b... Energy Nucleus-Nucleus Collisions." I have examined the final copy of this thesis for form and content and recommend that it be accepted in partial...School COALESCENCE EFFECTS ON NEUTRON PRODUCTION IN HIGH ENERGY NUCLEUS-NUCLEUS COLLISIONS A Thesis Presented for the Master of Science Degree The

  17. Stuttering in Parkinson's disease after deep brain stimulation: A note on dystonia and low-frequency stimulation.

    PubMed

    Mendonça, Marcelo D; Barbosa, Raquel; Seromenho-Santos, Alexandra; Reizinho, Carla; Bugalho, Paulo

    2018-04-01

    Stuttering, a speech fluency disorder, is a rare complication of Deep Brain Stimulation (DBS) in Parkinson's Disease (PD). We report a 61 years-old patient with PD, afflicted by severe On and Off dystonia, treated with Subthalamic Nucleus DBS that developed post-DBS stuttering while on 130 Hz stimulation. Stuttering reduction was noted when frequency was changed to 80 Hz, but the previously observed dystonia improvement was lost. There are no reports in literature on patients developing stuttering with low-frequency stimulation. We question if low-frequency stimulation could have a role for managing PD's post-DBS stuttering, and notice that stuttering improvement was associated with dystonia worsening suggesting that they are distinct phenomena. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. Highlight on the dynamic organization of the nucleus.

    PubMed

    Thorpe, Stephen D; Charpentier, Myriam

    2017-01-02

    The last decade has seen rapid advances in our understanding of the proteins of the nuclear envelope, which have multiple roles including positioning the nucleus, maintaining its structural organization, and in events ranging from mitosis and meiosis to chromatin positioning and gene expression. Diverse new and stimulating results relating to nuclear organization and genome function from across kingdoms were presented in a session stream entitled "Dynamic Organization of the Nucleus" at this year's Society of Experimental Biology (SEB) meeting in Brighton, UK (July 2016). This was the first session stream run by the Nuclear Dynamics Special Interest Group, which was organized by David Evans, Katja Graumann (both Oxford Brookes University, UK) and Iris Meier (Ohio State University, USA). The session featured presentations on areas relating to nuclear organization across kingdoms including the nuclear envelope, chromatin organization, and genome function.

  19. Magnetic resonance imaging of the subthalamic nucleus for deep brain stimulation.

    PubMed

    Chandran, Arjun S; Bynevelt, Michael; Lind, Christopher R P

    2016-01-01

    The subthalamic nucleus (STN) is one of the most important stereotactic targets in neurosurgery, and its accurate imaging is crucial. With improving MRI sequences there is impetus for direct targeting of the STN. High-quality, distortion-free images are paramount. Image reconstruction techniques appear to show the greatest promise in balancing the issue of geometrical distortion and STN edge detection. Existing spin echo- and susceptibility-based MRI sequences are compared with new image reconstruction methods. Quantitative susceptibility mapping is the most promising technique for stereotactic imaging of the STN.

  20. The Effect of Deep Brain Stimulation on the Speech Motor System

    ERIC Educational Resources Information Center

    Mücke, Doris; Becker, Johannes; Barbe, Michael T.; Meister, Ingo; Liebhart, Lena; Roettger, Timo B.; Dembek, Till; Timmermann, Lars; Grice, Martine

    2014-01-01

    Purpose: Chronic deep brain stimulation of the nucleus ventralis intermedius is an effective treatment for individuals with medication-resistant essential tremor. However, these individuals report that stimulation has a deleterious effect on their speech. The present study investigates one important factor leading to these effects: the…

  1. The effect of deep brain stimulation on the speech motor system.

    PubMed

    Mücke, Doris; Becker, Johannes; Barbe, Michael T; Meister, Ingo; Liebhart, Lena; Roettger, Timo B; Dembek, Till; Timmermann, Lars; Grice, Martine

    2014-08-01

    Chronic deep brain stimulation of the nucleus ventralis intermedius is an effective treatment for individuals with medication-resistant essential tremor. However, these individuals report that stimulation has a deleterious effect on their speech. The present study investigates one important factor leading to these effects: the coordination of oral and glottal articulation. Sixteen native-speaking German adults with essential tremor, between 26 and 86 years old, with and without chronic deep brain stimulation of the nucleus ventralis intermedius and 12 healthy, age-matched subjects were recorded performing a fast syllable repetition task (/papapa/, /tatata/, /kakaka/). Syllable duration and voicing-to-syllable ratio as well as parameters related directly to consonant production, voicing during constriction, and frication during constriction were measured. Voicing during constriction was greater in subjects with essential tremor than in controls, indicating a perseveration of voicing into the voiceless consonant. Stimulation led to fewer voiceless intervals (voicing-to-syllable ratio), indicating a reduced degree of glottal abduction during the entire syllable cycle. Stimulation also induced incomplete oral closures (frication during constriction), indicating imprecise oral articulation. The detrimental effect of stimulation on the speech motor system can be quantified using acoustic measures at the subsyllabic level.

  2. Glutamatergic Receptor Activation in the Commisural Nucleus Tractus Solitarii (cNTS) Mediates Brain Glucose Retention (BGR) Response to Anoxic Carotid Chemoreceptor (CChr) Stimulation in Rats.

    PubMed

    Cuéllar, R; Montero, S; Luquín, S; García-Estrada, J; Dobrovinskaya, O; Melnikov, V; Lemus, M; de Álvarez-Buylla, E Roces

    2015-01-01

    Glutamate, released from central terminals of glossopharyngeal nerve, is a major excitatory neurotransmitter of commissural nucleus tractus solitarii (cNTS) afferent terminals, and brain derived neurotrophic factor (BDNF) has been shown to attenuate glutamatergic AMPA currents in NTS neurons. To test the hypothesis that AMPA contributes to glucose regulation in vivo modulating the hyperglycemic reflex with brain glucose retention (BGR), we microinjected AMPA and NBQX (AMPA antagonist) into the cNTS before carotid chemoreceptor stimulation in anesthetized normal Wistar rats, while hyperglycemic reflex an brain glucose retention (BGR) were analyzed. To investigate the underlying mechanisms, GluR2/3 receptor and c-Fos protein expressions in cNTS neurons were determined. We showed that AMPA in the cNTS before CChr stimulation inhibited BGR observed in aCSF group. In contrast, NBQX in similar conditions, did not modify the effects on glucose variables observed in aCSF control group. These experiments suggest that glutamatergic pathways, via AMPA receptors, in the cNTS may play a role in glucose homeostasis.

  3. Effect of cochlear nerve electrocautery on the adult cochlear nucleus.

    PubMed

    Iseli, Claire E; Merwin, William H; Klatt-Cromwell, Cristine; Hutson, Kendall A; Ewend, Matthew G; Adunka, Oliver F; Fitzpatrick, Douglas C; Buchman, Craig A

    2015-04-01

    Electrocauterization and subsequent transection of the cochlear nerve induce greater injury to the cochlear nucleus than sharp transection alone. Some studies show that neurofibromatosis Type 2 (NF2) patients fit with auditory brainstem implants (ABIs) fail to achieve speech perception abilities similar to ABI recipients without NF2. Reasons for these differences remain speculative. One hypothesis posits poorer performance to surgically induced trauma to the cochlear nucleus from electrocautery. Sustained electrosurgical depolarization of the cochlear nerve may cause excitotoxic-induced postsynaptic nuclear injury. Equally plausible is that cautery in the vicinity of the cochlear nucleus induces necrosis. The cochlear nerve was transected in anesthetized adult gerbils sharply with or without bipolar electrocautery at varying intensities. Gerbils were perfused at 1, 3, 5, and 7 days postoperatively; their brainstem and cochleas were embedded in paraffin and sectioned at 10 μm. Alternate sections were stained with flourescent markers for neuronal injury or Nissl substance. In additional experiments, anterograde tracers were applied directly to a sectioned eighth nerve to verify that fluorescent-labeled profiles seen were terminating auditory nerve fibers. Cochlear nerve injury was observed from 72 hours postoperatively and was identical across cases regardless of surgical technique. Postsynaptic cochlear nucleus injury was not seen after distal transection of the nerve. By contrast, proximal transection was associated with trauma to the cochlear nucleus. Distal application of bipolar electrocautery seems safe for the cochlear nucleus. Application near the root entry zone must be used cautiously because this may compromise nuclear viability needed to support ABI stimulation.

  4. Frequency-dependent, transient effects of subthalamic nucleus deep brain stimulation on methamphetamine-induced circling and neuronal activity in the hemiparkinsonian rat.

    PubMed

    So, Rosa Q; McConnell, George C; Grill, Warren M

    2017-03-01

    Methamphetamine-induced circling is used to quantify the behavioral effects of subthalamic nucleus (STN) deep brain stimulation (DBS) in hemiparkinsonian rats. We observed a frequency-dependent transient effect of DBS on circling, and quantified this effect to determine its neuronal basis. High frequency STN DBS (75-260Hz) resulted in transient circling contralateral to the lesion at the onset of stimulation, which was not sustained after the first several seconds of stimulation. Following the transient behavioral change, DBS resulted in a frequency-dependent steady-state reduction in pathological ipsilateral circling, but no change in overall movement. Recordings from single neurons in globus pallidus externa (GPe) and substantia nigra pars reticulata (SNr) revealed that high frequency, but not low frequency, STN DBS elicited transient changes in both firing rate and neuronal oscillatory power at the stimulation frequency in a subpopulation of GPe and SNr neurons. These transient changes were not sustained, and most neurons exhibited a different response during the steady-state phase of DBS. During the steady-state, DBS produced elevated neuronal oscillatory power at the stimulus frequency in a majority of GPe and SNr neurons, and the increase was more pronounced during high frequency DBS than during low frequency DBS. Changes in oscillatory power during both transient and steady-state DBS were highly correlated with changes in firing rates. These results suggest that distinct neural mechanisms were responsible for transient and sustained behavioral responses to STN DBS. The transient contralateral turning behavior following the onset of high frequency DBS was paralleled by transient changes in firing rate and oscillatory power in the GPe and SNr, while steady-state suppression of ipsilateral turning was paralleled by sustained increased synchronization of basal ganglia neurons to the stimulus pulses. Our analysis of distinct frequency-dependent transient and

  5. Association between subthalamic nucleus deep brain stimulation and weight gain: Results of a case-control study.

    PubMed

    Strowd, Roy E; Herco, Maja; Passmore-Griffin, Leah; Avery, Bradley; Haq, Ihtsham; Tatter, Stephen B; Tate, Jessica; Siddiqui, Mustafa S

    2016-01-01

    To evaluate whether weight change in patients with Parkinson's disease (PD) is different in those undergoing deep brain stimulation (DBS) of the subthalamic nucleus (STN) compared to those not undergoing DBS. A retrospective case-control study was performed in PD patients who had undergone STN DBS (cases) compared to matched PD patients without DBS (controls). Demographic and clinical data including Unified Parkinson's Disease Rating Scale (UPDRS) motor scores were collected. Repeated measures mixed model regression was used to identify variables associated with weight gain. Thirty-five cases and 34 controls were identified. Baseline age, gender, diagnosis and weight were similar. Duration of diagnosis was longer in cases (6.3 vs 4.9 years, p=0.0015). At 21.3 months, cases gained 2.9 kg (+4.65%) while controls lost 1.8 kg (-3.05%, p<0.02). Postoperative UPDRS motor scores improved by 49% indicating surgical efficacy. Only younger age (p=0.0002) and DBS (p=0.008) were significantly associated with weight gain. In this case-control study, PD patients undergoing STN DBS experienced post-operative weight gain that was significantly different from the weight loss observed in non-DBS PD controls. Patients, especially overweight individuals, should be informed that STN DBS can result in weight gain. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Projections from the nucleus reticularis magnocellularis to the rat cervical cord using electrical stimulation and iontophoretic injection methods.

    PubMed

    Watanabe, Shigeo; Kitamura, Taiko; Watanabe, Lisa; Sato, Hitoshi; Yamada, Jinzo

    2003-03-01

    The aim of this study is to clarify the fiber distribution of the nucleus reticularis magnocellularis (NRMC) and adjacent areas in the rat spinal cord. Biotinylated dextran amine was injected iontophoretically through a glass capillary into the areas, in which a single cell responded to noxious electrical stimulation of the sciatic nerve and to a pinch of the thigh skin with multiple spikes. Labeled fibers descended bilaterally through the ventral funiculi of the medulla oblongata and then through the ventral and lateral funiculi of the cervical cord with an ipsilateral predominance, and terminated in the spinal gray (laminae I-X). A single fiber sometimes ran through several laminae while bifurcating many short branches with axon varicosities and terminal buttons in one transverse section, that is, through laminae V, VII and X, through laminae V, IIl-IV and I-II, and through laminae VII to I-II. The present study showed that the wide distribution of a single fiber and a mass of fibers descending from the NRMC and adjacent areas might modulate not only somatic sensory and motor functions but also autonomic functions in the spinal cord.

  7. Thalamic deep brain stimulation for writer's cramp.

    PubMed

    Fukaya, Chikashi; Katayama, Yoichi; Kano, Toshikazu; Nagaoka, Takafumi; Kobayashi, Kazutaka; Oshima, Hideki; Yamamoto, Takamitsu

    2007-11-01

    Writer's cramp is a type of idiopathic focal hand dystonia characterized by muscle cramps that accompany execution of the writing task specifically. In this report, the authors describe the clinical outcome after thalamic deep brain stimulation (DBS) therapy in patients with writer's cramp and present an illustrative case with which they compare the effects of pallidal and thalamic stimulation. In addition to these results for the clinical effectiveness, they also examine the best point and pattern for therapeutic stimulation of the motor thalamus, including the nucleus ventrooralis (VO) and the ventralis intermedius nucleus (VIM), for writer's cramp. The authors applied thalamic DBS in five patients with writer's cramp. The inclusion criteria for the DBS trial in this disorder were a diagnosis of idiopathic writer's cramp and the absence of a positive response to medication. The exclusion criteria included significant cognitive dysfunction, active psychiatric symptoms, and evidence of other central nervous system diseases or other medical disorders. In one of the cases, DBS leads were implanted into both the globus pallidus internus and the VO/VIM, and test stimulation was performed for 1 week. The authors thus had an opportunity to compare the effects of pallidal and thalamic stimulation in this patient. Immediately after the initiation of thalamic stimulation, the neurological deficits associated with writer's cramp were improved in all five cases. Postoperatively all preoperative scale scores indicating the seriousness of the writer's cramp were significantly lower (p < 0.001). In the patient in whom two DBS leads were implanted, the clinical effect of thalamic stimulation was better than that of pallidal stimulation. During the thalamic stimulation, the maximum effect was obtained when stimulation was applied to both the VO and the VIM widely, compared with being applied only within the VO. The authors successfully treated patients with writer's cramp by

  8. Periodic mechanical stress activates EGFR-dependent Rac1 mitogenic signals in rat nucleus pulpous cells via ERK1/2

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gao, Gongming; Shen, Nan; Jiang, Xuefeng

    2016-01-15

    The mitogenic effects of periodic mechanical stress on nucleus pulpous cells have been studied extensively but the mechanisms whereby nucleus pulpous cells sense and respond to mechanical stimulation remain a matter of debate. We explored this question by performing cell culture experiments in our self-developed periodic stress field and perfusion culture system. Under periodic mechanical stress, rat nucleus pulpous cell proliferation was significantly increased (p < 0.05 for each) and was associated with increases in the phosphorylation and activation of EGFR, Rac1, and ERK1/2 (p < 0.05 for each). Pretreatment with the ERK1/2 selective inhibitor PD98059 reduced periodic mechanical stress-induced nucleus pulpous cell proliferationmore » (p < 0.05 for each), while the activation levels of EGFR and Rac1 were not inhibited. Proliferation and phosphorylation of ERK1/2 were inhibited after pretreatment with the Rac1 inhibitor NSC23766 in nucleus pulpous cells in response to periodic mechanical stress (p < 0.05 for each), while the phosphorylation site of EGFR was not affected. Inhibition of EGFR activity with AG1478 abrogated nucleus pulpous cell proliferation (p < 0.05 for each) and attenuated Rac1 and ERK1/2 activation in nucleus pulpous cells subjected to periodic mechanical stress (p < 0.05 for each). These findings suggest that periodic mechanical stress promotes nucleus pulpous cell proliferation in part through the EGFR-Rac1-ERK1/2 signaling pathway, which links these three important signaling molecules into a mitogenic cascade. - Highlights: • The mechanism involved in nucleus pulpous cells to respond to mechanical stimuli. • Periodic mechanical stress can stimulate the phosphorylation of EGFR. • EGFR activates Rac1 and leads to rat nucleus pulpous cell proliferation. • EGFR and Rac1 activate ERK1/2 mitogenic signals in nucleus pulpous cells. • EGFR-Rac1-ERK1/2 is constitutes at least one critical signal transduction pathway.« less

  9. Epidermal growth factor receptors destined for the nucleus are internalized via a clathrin-dependent pathway

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    De Angelis Campos, Ana Carolina; Rodrigues, Michele Angela; Andrade, Carolina de

    2011-08-26

    Highlights: {yields} EGF and its receptor translocates to the nucleus in liver cells. {yields} Real time imaging shows that EGF moves to the nucleus. {yields} EGF moves with its receptor to the nucleus. {yields} Dynamin and clathrin are necessary for EGFR nuclear translocation. -- Abstract: The epidermal growth factor (EGF) transduces its actions via the EGF receptor (EGFR), which can traffic from the plasma membrane to either the cytoplasm or the nucleus. However, the mechanism by which EGFR reaches the nucleus is unclear. To investigate these questions, liver cells were analyzed by immunoblot of cell fractions, confocal immunofluorescence and realmore » time confocal imaging. Cell fractionation studies showed that EGFR was detectable in the nucleus after EGF stimulation with a peak in nuclear receptor after 10 min. Movement of EGFR to the nucleus was confirmed by confocal immunofluorescence and labeled EGF moved with the receptor to the nucleus. Small interference RNA (siRNA) was used to knockdown clathrin in order to assess the first endocytic steps of EGFR nuclear translocation in liver cells. A mutant dynamin (dynamin K44A) was also used to determine the pathways for this traffic. Movement of labeled EGF or EGFR to the nucleus depended upon dynamin and clathrin. This identifies the pathway that mediates the first steps for EGFR nuclear translocation in liver cells.« less

  10. Subthalamic nucleus stimulation selectively improves motor and visual memory performance in Parkinson's disease.

    PubMed

    Mollion, Hélène; Dominey, Peter Ford; Broussolle, Emmanuel; Ventre-Dominey, Jocelyne

    2011-09-01

    Although the treatment of Parkinson's disease via subthalamic stimulation yields remarkable improvements in motor symptoms, its effects on memory function are less clear. In this context, we previously demonstrated dissociable effects of levodopa therapy on parkinsonian performance in spatial and nonspatial visual working memory. Here we used the same protocol with an additional, purely motor task to investigate visual memory and motor performance in 2 groups of patients with Parkinson's disease with or without subthalamic stimulation. In each stimulation condition, subjects performed a simple motor task and 3 successive cognitive tasks: 1 conditional color-response association task and 2 visual (spatial and nonspatial) working memory tasks. The Parkinson's groups were compared with a control group of age-matched healthy subjects. Our principal results demonstrated that (1) in the motor task, stimulated patients were significantly improved with respect to nonstimulated patients and did not differ significantly from healthy controls, and (2) in the cognitive tasks, stimulated patients were significantly improved with respect to nonstimulated patients, but both remained significantly impaired when compared with healthy controls. These results demonstrate selective effects of subthalamic stimulation on parkinsonian disorders of motor and visual memory functions, with clear motor improvement for stimulated patients and a partial improvement for their visual memory processing. Copyright © 2011 Movement Disorder Society.

  11. Role of the hypothalamic arcuate nucleus in cardiovascular regulation

    PubMed Central

    Sapru, Hreday N.

    2012-01-01

    Recently the hypothalamic arcuate nucleus (Arc) has been implicated in cardiovascular regulation. Both pressor and depressor responses can be elicited by the chemical stimulation of the Arc. The direction of cardiovascular responses (increase or decrease) elicited from the Arc depends on the baseline blood pressure. The pressor responses are mediated via increase in sympathetic nerve activity and involve activation of the spinal ionotropic glutamate receptors. Arc-stimulation elicits tachycardic responses which are mediated via inhibition of vagal input and excitation of sympathetic input to the heart. The pathways within the brain mediating the pressor and tachycardic responses elicited from the Arc have not been delineated. The depressor responses to the Arc-stimulation are mediated via the hypothalamic paraventricular nucleus (PVN). Gamma aminobutyric acid type A receptors, neuropeptide Y1 receptors, and opiate receptors in the PVN mediate the depressor responses elicited from the Arc. Some circulating hormones (e.g., leptin and insulin) may reach the Arc via the leaky blood-brain barrier and elicit their cardiovascular effects. Although the Arc is involved in mediating the cardiovascular responses to intravenously injected angiotensin II and angiotensin-(1-12), these effects may not be due to leakage of these peptides across the blood-brain barrier in the Arc; instead, circulating angiotensins may act on neurons in the SFO and mediate cardiovascular actions via the projections of SFO neurons to the Arc. Cardiovascular responses elicited by acupuncture have been reported to be mediated by direct and indirect projections of the Arc to the RVLM. PMID:23260431

  12. Crowding, Entropic Forces, and Confinement: Crucial Factors for Structures and Functions in the Cell Nucleus.

    PubMed

    Hancock, R

    2018-04-01

    The view of the cell nucleus as a crowded system of colloid particles and that chromosomes are giant self-avoiding polymers is stimulating rapid advances in our understanding of its structure and activities, thanks to concepts and experimental methods from colloid, polymer, soft matter, and nano sciences and to increased computational power for simulating macromolecules and polymers. This review summarizes current understanding of some characteristics of the molecular environment in the nucleus, of how intranuclear compartments are formed, and of how the genome is highly but precisely compacted, and underlines the crucial, subtle, and sometimes unintuitive effects on structures and reactions of entropic forces caused by the high concentration of macromolecules in the nucleus.

  13. SUBTHALAMIC NUCLEUS NEURONS DIFFERENTIALLY ENCODE EARLY AND LATE ASPECTS OF SPEECH PRODUCTION.

    PubMed

    Lipski, W J; Alhourani, A; Pirnia, T; Jones, P W; Dastolfo-Hromack, C; Helou, L B; Crammond, D J; Shaiman, S; Dickey, M W; Holt, L L; Turner, R S; Fiez, J A; Richardson, R M

    2018-05-22

    Basal ganglia-thalamocortical loops mediate all motor behavior, yet little detail is known about the role of basal ganglia nuclei in speech production. Using intracranial recording during deep brain stimulation surgery in humans with Parkinson's disease, we tested the hypothesis that the firing rate of subthalamic nucleus neurons is modulated in sync with motor execution aspects of speech. Nearly half of seventy-nine unit recordings exhibited firing rate modulation, during a syllable reading task across twelve subjects (male and female). Trial-to-trial timing of changes in subthalamic neuronal activity, relative to cue onset versus production onset, revealed that locking to cue presentation was associated more with units that decreased firing rate, while locking to speech onset was associated more with units that increased firing rate. These unique data indicate that subthalamic activity is dynamic during the production of speech, reflecting temporally-dependent inhibition and excitation of separate populations of subthalamic neurons. SIGNIFICANCE STATEMENT The basal ganglia are widely assumed to participate in speech production, yet no prior studies have reported detailed examination of speech-related activity in basal ganglia nuclei. Using microelectrode recordings from the subthalamic nucleus during a single syllable reading task, in awake humans undergoing deep brain stimulation implantation surgery, we show that the firing rate of subthalamic nucleus neurons is modulated in response to motor execution aspects of speech. These results are the first to establish a role for subthalamic nucleus neurons in encoding of aspects of speech production, and they lay the groundwork for launching a modern subfield to explore basal ganglia function in human speech. Copyright © 2018 the authors.

  14. Regular theta-firing neurons in the nucleus incertus during sustained hippocampal activation.

    PubMed

    Martínez-Bellver, Sergio; Cervera-Ferri, Ana; Martínez-Ricós, Joana; Ruiz-Torner, Amparo; Luque-Garcia, Aina; Luque-Martinez, Aina; Blasco-Serra, Arantxa; Guerrero-Martínez, Juan; Bataller-Mompeán, Manuel; Teruel-Martí, Vicent

    2015-04-01

    This paper describes the existence of theta-coupled neuronal activity in the nucleus incertus (NI). Theta rhythm is relevant for cognitive processes such as spatial navigation and memory processing, and can be recorded in a number of structures related to the hippocampal activation including the NI. Strong evidence supports the role of this tegmental nucleus in neural circuits integrating behavioural activation with the hippocampal theta rhythm. Theta oscillations have been recorded in the local field potential of the NI, highly coupled to the hippocampal waves, although no rhythmical activity has been reported in neurons of this nucleus. The present work analyses the neuronal activity in the NI in conditions leading to sustained hippocampal theta in the urethane-anaesthetised rat, in order to test whether such activation elicits a differential firing pattern. Wavelet analysis has been used to better define the neuronal activity already described in the nucleus, i.e., non-rhythmical neurons firing at theta frequency (type I neurons) and fast-firing rhythmical neurons (type II). However, the most remarkable finding was that sustained stimulation activated regular-theta neurons (type III), which were almost silent in baseline conditions and have not previously been reported. Thus, we describe the electrophysiological properties of type III neurons, focusing on their coupling to the hippocampal theta. Their spike rate, regularity and phase locking to the oscillations increased at the beginning of the stimulation, suggesting a role in the activation or reset of the oscillation. Further research is needed to address the specific contribution of these neurons to the entire circuit. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  15. Direct and indirect nigrofugal projections to the nucleus reticularis pontis caudalis mediate in the motor execution of the acoustic startle reflex.

    PubMed

    Hormigo, Sebastian; López, Dolores E; Cardoso, Antonio; Zapata, Gladys; Sepúlveda, Jacqueline; Castellano, Orlando

    2018-07-01

    The acoustic startle reflex (ASR) is a short and intense defensive reaction in response to a loud and unexpected acoustic stimulus. In the rat, a primary startle pathway encompasses three serially connected central structures: the cochlear root neurons, the giant neurons of the nucleus reticularis pontis caudalis (PnC), and the spinal motoneurons. As a sensorimotor interface, the PnC has a central role in the ASR circuitry, especially the integration of different sensory stimuli and brain states into initiation of motor responses. Since the basal ganglia circuits control movement and action selection, we hypothesize that their output via the substantia nigra (SN) may interplay with the ASR primary circuit by providing inputs to PnC. Moreover, the pedunculopontine tegmental nucleus (PPTg) has been proposed as a functional and neural extension of the SN, so it is another goal of this study to describe possible anatomical connections from the PPTg to PnC. Here, we made 6-OHDA neurotoxic lesions of the SN pars compacta (SNc) and submitted the rats to a custom-built ASR measurement session to assess amplitude and latency of motor responses. We found that following lesion of the SNc, ASR amplitude decreased and latency increased compared to those values from the sham-surgery and control groups. The number of dopamine neurons remaining in the SNc after lesion was also estimated using a stereological approach, and it correlated with our behavioral results. Moreover, we employed neural tract-tracing techniques to highlight direct projections from the SN to PnC, and indirect projections through the PPTg. Finally, we also measured levels of excitatory amino acid neurotransmitters in the PnC following lesion of the SN, and found that they change following an ipsi/contralateral pattern. Taken together, our results identify nigrofugal efferents onto the primary ASR circuit that may modulate motor responses.

  16. Panic and fear induced by deep brain stimulation.

    PubMed

    Shapira, N A; Okun, M S; Wint, D; Foote, K D; Byars, J A; Bowers, D; Springer, U S; Lang, P J; Greenberg, B D; Haber, S N; Goodman, W K

    2006-03-01

    Mood, cognitive, and behavioural changes have been reported with deep brain stimulation (DBS) in the thalamus, globus pallidus interna, and anterior limb of the internal capsule/nucleus accumbens region. To investigate panic and fear resulting from DBS. Intraoperative DBS in the region of the right and then left anterior limb of the internal capsule and nucleus accumbens region was undertaken to treat a 52 year old man with treatment refractory obsessive-compulsive disorder (OCD). Mood, anxiety, OCD, alertness, heart rate, and subjective feelings were recorded during intraoperative test stimulation and at follow up programming sessions. DBS at the distal (0) contact (cathode 0-, anode 2+, pulse width 210 ms, rate 135 Hz, at 6 volts) elicited a panic attack (only seen at the (0) contact). The patient felt flushed, hot, fearful, and described himself as having a "panic attack." His heart rate increased from 53 to 111. The effect (present with either device) was witnessed immediately after turning the device on, and abruptly ceased in the off condition DBS of the anterior limb of the internal capsule and nucleus accumbens region caused severe "panic." This response may result from activation of limbic and autonomic networks.

  17. Parkinsonian gait improves with bilateral subthalamic nucleus deep brain stimulation during cognitive multi-tasking.

    PubMed

    Chenji, Gaurav; Wright, Melissa L; Chou, Kelvin L; Seidler, Rachael D; Patil, Parag G

    2017-05-01

    Gait impairment in Parkinson's disease reduces mobility and increases fall risk, particularly during cognitive multi-tasking. Studies suggest that bilateral subthalamic deep brain stimulation, a common surgical therapy, degrades motor performance under cognitive dual-task conditions, compared to unilateral stimulation. To measure the impact of bilateral versus unilateral subthalamic deep brain stimulation on walking kinematics with and without cognitive dual-tasking. Gait kinematics of seventeen patients with advanced Parkinson's disease who had undergone bilateral subthalamic deep brain stimulation were examined off medication under three stimulation states (bilateral, unilateral left, unilateral right) with and without a cognitive challenge, using an instrumented walkway system. Consistent with earlier studies, gait performance declined for all six measured parameters under cognitive dual-task conditions, independent of stimulation state. However, bilateral stimulation produced greater improvements in step length and double-limb support time than unilateral stimulation, and achieved similar performance for other gait parameters. Contrary to expectations from earlier studies of dual-task motor performance, bilateral subthalamic deep brain stimulation may assist in maintaining temporal and spatial gait performance under cognitive dual-task conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Rat Nucleus Accumbens Core Astrocytes Modulate Reward and the Motivation to Self-Administer Ethanol after Abstinence

    PubMed Central

    Bull, Cecilia; Freitas, Kelen CC; Zou, Shiping; Poland, Ryan S; Syed, Wahab A; Urban, Daniel J; Minter, Sabrina C; Shelton, Keith L; Hauser, Kurt F; Negus, S Stevens; Knapp, Pamela E; Bowers, M Scott

    2014-01-01

    Our understanding of the active role that astrocytes play in modulating neuronal function and behavior is rapidly expanding, but little is known about the role that astrocytes may play in drug-seeking behavior for commonly abused substances. Given that the nucleus accumbens is critically involved in substance abuse and motivation, we sought to determine whether nucleus accumbens astrocytes influence the motivation to self-administer ethanol following abstinence. We found that the packing density of astrocytes that were expressing glial fibrillary acidic protein increased in the nucleus accumbens core (NAcore) during abstinence from EtOH self-administration. No change was observed in the nucleus accumbens shell. This increased NAcore astrocyte density positively correlated with the motivation for ethanol. Astrocytes can communicate with one another and influence neuronal activity through gap-junction hemichannels. Because of this, the effect of blocking gap-junction hemichannels on the motivation for ethanol was examined. The motivation to self-administer ethanol after 3 weeks abstinence was increased following microinjection of gap-junction hemichannel blockers into the NAcore at doses that block both neuronal and astrocytic channels. In contrast, no effect was observed following microinjection of doses that are not thought to block astrocytic channels or following microinjection of either dose into the nucleus accumbens shell. Additionally, the motivation for sucrose after 3 weeks abstinence was unaffected by NAcore gap-junction hemichannel blockers. Next, Designer Receptors Exclusively Activated by Designer Drugs (DREADDs) were selectively expressed in NAcore astrocytes to test the effect of astrocyte stimulation. DREADD activation increased cytosolic calcium in primary astrocytes, facilitated responding for rewarding brain stimulation, and reduced the motivation for ethanol after 3 weeks abstinence. This is the first work to modulate drug-seeking behavior with

  19. Rat nucleus accumbens core astrocytes modulate reward and the motivation to self-administer ethanol after abstinence.

    PubMed

    Bull, Cecilia; Freitas, Kelen C C; Zou, Shiping; Poland, Ryan S; Syed, Wahab A; Urban, Daniel J; Minter, Sabrina C; Shelton, Keith L; Hauser, Kurt F; Negus, S Stevens; Knapp, Pamela E; Bowers, M Scott

    2014-11-01

    Our understanding of the active role that astrocytes play in modulating neuronal function and behavior is rapidly expanding, but little is known about the role that astrocytes may play in drug-seeking behavior for commonly abused substances. Given that the nucleus accumbens is critically involved in substance abuse and motivation, we sought to determine whether nucleus accumbens astrocytes influence the motivation to self-administer ethanol following abstinence. We found that the packing density of astrocytes that were expressing glial fibrillary acidic protein increased in the nucleus accumbens core (NAcore) during abstinence from EtOH self-administration. No change was observed in the nucleus accumbens shell. This increased NAcore astrocyte density positively correlated with the motivation for ethanol. Astrocytes can communicate with one another and influence neuronal activity through gap-junction hemichannels. Because of this, the effect of blocking gap-junction hemichannels on the motivation for ethanol was examined. The motivation to self-administer ethanol after 3 weeks abstinence was increased following microinjection of gap-junction hemichannel blockers into the NAcore at doses that block both neuronal and astrocytic channels. In contrast, no effect was observed following microinjection of doses that are not thought to block astrocytic channels or following microinjection of either dose into the nucleus accumbens shell. Additionally, the motivation for sucrose after 3 weeks abstinence was unaffected by NAcore gap-junction hemichannel blockers. Next, Designer Receptors Exclusively Activated by Designer Drugs (DREADDs) were selectively expressed in NAcore astrocytes to test the effect of astrocyte stimulation. DREADD activation increased cytosolic calcium in primary astrocytes, facilitated responding for rewarding brain stimulation, and reduced the motivation for ethanol after 3 weeks abstinence. This is the first work to modulate drug-seeking behavior with

  20. Ipsilateral masking between acoustic and electric stimulations.

    PubMed

    Lin, Payton; Turner, Christopher W; Gantz, Bruce J; Djalilian, Hamid R; Zeng, Fan-Gang

    2011-08-01

    Residual acoustic hearing can be preserved in the same ear following cochlear implantation with minimally traumatic surgical techniques and short-electrode arrays. The combined electric-acoustic stimulation significantly improves cochlear implant performance, particularly speech recognition in noise. The present study measures simultaneous masking by electric pulses on acoustic pure tones, or vice versa, to investigate electric-acoustic interactions and their underlying psychophysical mechanisms. Six subjects, with acoustic hearing preserved at low frequencies in their implanted ear, participated in the study. One subject had a fully inserted 24 mm Nucleus Freedom array and five subjects had Iowa/Nucleus hybrid implants that were only 10 mm in length. Electric masking data of the long-electrode subject showed that stimulation from the most apical electrodes produced threshold elevations over 10 dB for 500, 625, and 750 Hz probe tones, but no elevation for 125 and 250 Hz tones. On the contrary, electric stimulation did not produce any electric masking in the short-electrode subjects. In the acoustic masking experiment, 125-750 Hz pure tones were used to acoustically mask electric stimulation. The acoustic masking results showed that, independent of pure tone frequency, both long- and short-electrode subjects showed threshold elevations at apical and basal electrodes. The present results can be interpreted in terms of underlying physiological mechanisms related to either place-dependent peripheral masking or place-independent central masking.

  1. Analgesia induced by morphine microinjected into the nucleus raphe magnus: effects on tonic pain.

    PubMed

    Dualé, Christian; Sierralta, Fernando; Dallel, Radhouane

    2007-07-01

    One of the possible sites of action of the analgesic effect of morphine is the Nucleus Raphe Magnus, as morphine injected into this structure induces analgesia in transient pain models. In order to test if morphine in the Nucleus Raphe Magnus is also analgesic in a tonic pain model, 5 microg of morphine or saline (control) were microinjected into the Nucleus Raphe Magnus of the rat. Analgesic effects were assessed following nociceptive stimulation using transient heating of the tail (phasic pain) and subcutaneous orofacial injection of 1.5 % formalin (tonic pain). While morphine was strongly analgesic for the tail-flick response (p <0.0001 compared to control), analgesia on the response to formalin was also observed for both early (p = 0.007) and late responses (p = 0.02). However, the response to formalin was not completely blunted. These results suggest that the Nucleus Raphe Magnus is not the exclusive site of action of morphine-induced analgesia in clinical conditions.

  2. Changes in Nutritional Status after Deep Brain Stimulation of the Nucleus Basalis of Meynert in Alzheimer's Disease--Results of a Phase I Study.

    PubMed

    Noreik, M; Kuhn, J; Hardenacke, K; Lenartz, D; Bauer, A; Bührle, C P; Häussermann, P; Hellmich, M; Klosterkötter, J; Wiltfang, J; Maarouf, M; Freund, H-J; Visser-Vandewalle, V; Sturm, V; Schulz, R-J

    2015-10-01

    The progression of Alzheimer's disease (AD) is associated with impaired nutritional status. New methods, such as deep brain stimulation (DBS), are currently being tested to decrease the progression of AD. DBS is an approved method in the treatment of Parkinson's disease, and its suitability for the treatment of AD patients is currently under experimental investigation. To evaluate the advantages and disadvantages of this new treatment, it is important to assess potential side effects of DBS regarding the nucleus basalis of Meynert; this new treatment is thought to positively affect cognition and might counteract the deterioration of nutritional status and progressive weight loss observed in AD. This study aims to assess the nutritional status of patients with AD before receiving DBS of the nucleus basalis of Meynert and after 1 year, and to analyze potential associations between changes in cognition and nutritional status. A 1-year phase I proof-of-concept study. The Department of Psychiatry and Psychotherapy at the University of Cologne. We assessed a consecutive sample of patients with mild to moderate AD (n=6) who fulfilled the inclusion criteria and provided written informed consent. Bilateral low-frequency DBS of the nucleus basalis of Meynert. Nutritional status was assessed using a modified Mini Nutritional Assessment, bioelectrical impedance analysis, a completed 3-day food diary, and analysis of serum levels of vitamin B12 and folate. With a normal body mass index (BMI) at baseline (mean 23.75 kg/m²) and after 1 year (mean 24.59 kg/m²), all but one patient gained body weight during the period of the pilot study (mean 2.38 kg, 3.81% of body weight). This was reflected in a mainly stable or improved body composition, assessed by bioelectrical impedance analysis, in five of the six patients. Mean energy intake increased from 1534 kcal/day (min 1037, max 2370) at baseline to 1736 kcal/day (min 1010, max 2663) after 1 year, leading to the improved fulfillment

  3. Leptin and insulin stimulation of signalling pathways in arcuate nucleus neurones: PI3K dependent actin reorganization and KATP channel activation

    PubMed Central

    Mirshamsi, Shirin; Laidlaw, Hilary A; Ning, Ke; Anderson, Erin; Burgess, Laura A; Gray, Alexander; Sutherland, Calum; Ashford, Michael LJ

    2004-01-01

    Background Leptin and insulin are long-term regulators of body weight. They act in hypothalamic centres to modulate the function of specific neuronal subtypes, by altering transcriptional control of releasable peptides and by modifying neuronal electrical activity. A key cellular signalling intermediate, implicated in control of food intake by these hormones, is the enzyme phosphoinositide 3-kinase. In this study we have explored further the linkage between this enzyme and other cellular mediators of leptin and insulin action on rat arcuate nucleus neurones and the mouse hypothalamic cell line, GT1-7. Results Leptin and insulin increased the levels of various phosphorylated signalling intermediates, associated with the JAK2-STAT3, MAPK and PI3K cascades in the arcuate nucleus. Inhibitors of PI3K were shown to reduce the hormone driven phosphorylation through the PI3K and MAPK pathways. Using isolated arcuate neurones, leptin and insulin were demonstrated to increase the activity of KATP channels in a PI3K dependent manner, and to increase levels of PtdIns(3,4,5)P3. KATP activation by these hormones in arcuate neurones was also sensitive to the presence of the actin filament stabilising toxin, jasplakinolide. Using confocal imaging of fluorescently labelled actin and direct analysis of G- and F-actin concentration in GT1-7 cells, leptin was demonstrated directly to induce a re-organization of cellular actin, by increasing levels of globular actin at the expense of filamentous actin in a PI3-kinase dependent manner. Leptin stimulated PI3-kinase activity in GT1-7 cells and an increase in PtdIns(3,4,5)P3 could be detected, which was prevented by PI3K inhibitors. Conclusions Leptin and insulin mediated phosphorylation of cellular signalling intermediates and of KATP channel activation in arcuate neurones is sensitive to PI3K inhibition, thus strengthening further the likely importance of this enzyme in leptin and insulin mediated energy homeostasis control. The

  4. A Psychophysics experimental software to evaluate electrical pitch discrimination in Nucleus cochlear implanted patients

    NASA Astrophysics Data System (ADS)

    Pérez Zaballos, M. T.; Ramos de Miguel, A.; Killian, M.; Ramos Macías, A.

    2016-02-01

    Multichannel electrode array design in cochlear implants has evolved into two major categories: straight and perimodiolar electrodes. When implanted, the former lies along the outer wall of the scala tympani, while the later are located closer to the modiolus, where the neural ends are. Therefore, a perimodiolar position of the electrode array could be expected to result in reduced stimulus thresholds and stimulating currents, increased dynamic range, and more localized stimulation of the neural elements. However, their advantage for pitch discrimination has not been conclusively stated. Therefore, in order to study electrode independence, a psychophysical software has been developed, making use of Nucleus Implant Communicator tools provided by Cochlear company under a research agreement. The application comprises a graphical interface to facilitate its use, since previous software has always required some type of computer language skills. It allows for customization of electrical pulse parameters, measurement of threshold and comfort levels, loudness balancing and alternative forced choice experiments to determine electrode discrimination in Nucleus© users.

  5. Pontine regulation of REM sleep components in cats: integrity of the pedunculopontine tegmentum (PPT) is important for phasic events but unnecessary for atonia during REM sleep.

    PubMed

    Shouse, M N; Siegel, J M

    1992-01-31

    Transection, lesion and unit recording studies have localized rapid eye movement (REM) sleep mechanisms to the pons. Recent work has emphasized the role of pontine cholinergic cells, especially those of the pedunculopontine tegmentum (PPT). The present study differentiated REM sleep deficits associated with lesions of the PPT from other pontine regions implicated in REM sleep generation, including those with predominantly cholinergic vs non-cholinergic cells. Twelve hour polygraphic recordings were obtained in 18 cats before and 1-2 weeks after bilateral electrolytic or radio frequency lesions of either: (1) PPT, which contains the dorsolateral pontine cholinergic cell column; (2) laterodorsal tegmental nucleus (LDT), which contains the dorsomedial pontine cholinergic cell column; (3) locus ceruleus (LC), which contains mostly noradrenergic cells; or (4) subceruleus (LC alpha, peri-LC alpha and the lateral tegmental field), which also contains predominantly noncholinergic cells. There were three main findings: (i) Only lesions of PPT and subceruleus significantly affected REM sleep time. These lesions produced comparable reductions in REM sleep time but influenced REM sleep components quite differently: (ii) PPT lesions, estimated to damage 90 +/- 4% of cholinergic cells, reduced the number of REM sleep entrances and phasic events, including ponto-geniculooccipital (PGO) spikes and rapid eye movements (REMs), but did not prevent complete atonia during REM sleep: (iii) Subceruleus lesions eliminated atonia during REM sleep. Mobility appeared to arouse the cat prematurely from REM sleep and may explain the brief duration of REM sleep epochs seen exclusively in this group. Despite the reduced amount of REM sleep, the total number of PGO spikes and REM sleep entrances increased over baseline values. Collectively, the results distinguish pontine loci regulating phasic events vs atonia. PPT lesions reduced phasic events, whereas subceruleus lesions created REM sleep

  6. Stimulation of pontine reticular formation in monkeys with strabismus.

    PubMed

    Walton, Mark M G; Ono, Seiji; Mustari, Michael J

    2013-10-29

    Saccade disconjugacy in strabismus could result from any of a number of factors, including abnormalities of eye muscles, the plant, motoneurons, near response cells, or atypical tuning of neurons in saccade-related areas of the brain. This study was designed to investigate the possibility that saccade disconjugacy in strabismus is associated with abnormalities in paramedian pontine reticular formation (PPRF). We applied microstimulation to 22 sites in PPRF and 20 sites in abducens nucleus in three rhesus macaque monkeys (one normal, one esotrope, and one exotrope). When mean velocity was compared between the two eyes, a slight difference was found for 1/5 sites in the normal animal. Significant differences were found for 5/6 sites in an esotrope and 10/11 sites in an exotrope. For five sites in the strabismic monkeys, the directions of evoked movements differed by more than 40° between the two eyes. When stimulation was applied to abducens nucleus (20 sites), the ipsilateral eye moved faster for 4/6 sites in the normal animal and all nine sites in the esotrope. For the exotrope, however, the left eye always moved faster, even for three sites on the right side. For the strabismic animals, stimulation of abducens nucleus often caused a different eye to move faster than stimulation of PPRF. These data suggest that PPRF is organized at least partly monocularly in strabismus and that disconjugate saccades are at least partly a consequence of unbalanced saccadic commands being sent to the two eyes.

  7. [Effects of bilateral deep brain stimulation in the subthalamic nucleus using two methods of target structure verification].

    PubMed

    Goubareva, N N; Fedorova, N V; Bril', E V; Tomskiy, A A; Gamaleya, A A; Poddubskaya, A A; Shabalov, V A; Omarova, S M

    To evaluate the efficacy of deep brain stimulation in the subthalamic nucleus (DBS STN) in patients with Parkinson's disease (PD) using different methods of targeting according to the dynamics of motor symptoms of PD. The study involved 90 patients treated with DBS STN. In 30 cases intraoperative microelectrode recording (MER) was used. MER was not performed in 30 patients of the comparison group. The control group consisted of 30 patients with PD who received conservative treatment. Hoehn and Yahr scale, Tinetti Balance and Mobility Scale (TBMS), Unified Parkinson's Disease Rating Scale (UPDRS), Parkinson's Disease Quality of Life-39 Scoring System (РDQ-39), Schwab & England ADL Scale were used. Levodopa equivalent daily dose (LEDD, 2010) was calculated for each patient. The effect of DBS STN using intraoperative microelectrode recording on the main motor symptoms, motor complications, walking as well as indicators of quality of life and daily activities was shown. In both DBS STN groups, there was a significant reduction in the LEDD and marked improvement of the control of motor symptoms of PD. A significant reduction in the severity of motor fluctuations (50%) and drug-induced dyskinesia (51%) was observed. Quality of life and daily activity in off-medication condition were significantly improved in both DBS STN groups of patients, irrespective of the method of target planning (75-100%), compared with the control group.

  8. Responses of neurons in paramedian reticular nucleus to chemical stimulations and alteration of blood pressure in rats.

    PubMed

    Lin, A M; Wang, Y; Su, C K; Lee, E H; Kuo, J S; Chai, C Y

    1991-01-01

    Previous studies have shown that paramedian reticular nucleus (PRN) possessed sympathetic and parasympathetic inhibitions on autonomic nervous system. In the present study, the cardiovascular reactions of PRN by locally-applied DL-homocysteic acid (DLH), acetylcholine (ACh), monoamines and electrophysiological properties of PRN neurons responding to intravenous injection of ACh and NE were studied in adult Sprague-Dawley rats. In PRN, electrical stimulation caused hypotension and mild bradycardia while microinjection of DLH, which excites only cell body of the neurons but not passing fibers, evoked similar responses. Furthermore, direct application of ACh, norepinephrine (NE) or serotonin (5-HT) in PRN also produced hypotension, suggesting that these putative neurotransmitters may be involved in the cardiovascular responses in PRN. The electrophysiological properties of PRN neurons were studied: Neurons in PRN could be categorized into three types according to their neuronal activities in response to the changes of systemic arterial blood pressure (SAP) by ACh or NE given intravenously. Type I neurons (25/69) were activated in the same direction of SAP changes. Type II neurons (17/69) responded opposite to the direction of SAP changes. Type III neurons (27/69) responded inconsistently to the changes of SAP. All the three types of neurons were excited by locally-applied DLH and possessed a similar unfiltered action potential duration of greater than 0.5 msec.

  9. Morphine treatment enhances glutamatergic input onto neurons of the nucleus accumbens via both disinhibitory and stimulating effect.

    PubMed

    Yuan, Kejing; Sheng, Huan; Song, Jiaojiao; Yang, Li; Cui, Dongyang; Ma, Qianqian; Zhang, Wen; Lai, Bin; Chen, Ming; Zheng, Ping

    2017-11-01

    Drug addiction is a chronic brain disorder characterized by the compulsive repeated use of drugs. The reinforcing effect of repeated use of drugs on reward plays an important role in morphine-induced addictive behaviors. The nucleus accumbens (NAc) is an important site where morphine treatment produces its reinforcing effect on reward. However, how morphine treatment produces its reinforcing effect on reward in the NAc remains to be clarified. In the present study, we studied the influence of morphine treatment on the effects of DA and observed whether morphine treatment could directly change glutamatergic synaptic transmission in the NAc. We also explored the functional significance of morphine-induced potentiation of glutamatergic synaptic transmission in the NAc at behavioral level. Our results show that (1) morphine treatment removes the inhibitory effect of DA on glutamatergic input onto NAc neurons; (2) morphine treatment potentiates glutamatergic input onto NAc neurons, especially the one from the basolateral amygdala (BLA) to the NAc; (3) blockade of glutamatergic synaptic transmission in the NAc or ablation of projection neurons from BLA to NAc significantly decreases morphine treatment-induced increase in locomotor activity. These results suggest that morphine treatment enhances glutamatergic input onto neurons of the NAc via both disinhibitory and stimulating effect and therefore increases locomotor activity. © 2016 Society for the Study of Addiction.

  10. Supraspinal control of automatic postural responses in people with multiple sclerosis.

    PubMed

    Peterson, D S; Gera, G; Horak, F B; Fling, B W

    2016-06-01

    The neural underpinnings of delayed automatic postural responses in people with multiple sclerosis (PwMS) are unclear. We assessed whether white matter pathways of two supraspinal regions (the cortical proprioceptive Broadman's Area-3; and the balance/locomotor-related pedunculopontine nucleus) were related to delayed postural muscle response latencies in response to external perturbations. 19 PwMS (48.8±11.4years; EDSS=3.5 (range: 2-4)) and 12 healthy adults (51.7±12.2years) underwent 20 discrete, backward translations of a support surface. Onset latency of agonist (medial-gastrocnemius) and antagonist (tibialis anterior) muscles were assessed. Diffusion tensor imaging assessed white-matter integrity (i.e. radial diffusivity) of cortical proprioceptive and balance/locomotor-related tracts. Latency of the tibialis anterior, but not medial gastrocnemius was larger in PwMS than control subjects (p=0.012 and 0.071, respectively). Radial diffusivity of balance/locomotor tracts was higher (worse) in PwMS than control subjects (p=0.004), and was significantly correlated with tibialis (p=0.002), but not gastrocnemius (p=0.06) onset latency. Diffusivity of cortical proprioceptive tracts was not correlated with muscle onset. Lesions in supraspinal structures including the pedunculopontine nucleus balance/locomotor network may contribute to delayed onset of postural muscle activity in PwMS, contributing to balance deficits in PwMS. Published by Elsevier B.V.

  11. The nucleus parvocellularis reticularis regulates submandibular-sublingual salivary secretion in the rat: a pharmacological study.

    PubMed

    Ramos, J M; Puerto, A

    1988-09-01

    This experiment shows that activation of the nucleus parvocellularis reticularis in the rat brainstem provokes salivary hypersecretion by the submandibular-sublingual glands. The secretory effect is mediated by cholinergic mechanisms, as the administration of atropine blocked the flow of saliva evoked by stimulation of the nucleus parvocellularis. In contrast, injection of dihydroergotamine (an alpha-blocker) and/or propranolol (a beta-blocker) failed to significantly reduce submandibular and sublingual salivary secretion when compared to a control group injected with distilled water. The cholinergic nature of the salivary response suggests that the nucleus parvocellularis reticularis exerts its secretory effect on the salivary glands parasympathetically rather than through mechanisms associated with sympathetic pathways. The area of the brainstem activated in the present study closely overlaps the region in which cell bodies of superior salivatory neurons have recently been identified with retrograde transport of peroxidase. The data presented herein represent functional proof in support of the location of the superior salivatory nucleus within the parvocellularis reticular formation.

  12. Deep brain stimulation reveals a dissociation of consummatory and motivated behaviour in the medial and lateral nucleus accumbens shell of the rat.

    PubMed

    van der Plasse, Geoffrey; Schrama, Regina; van Seters, Sebastiaan P; Vanderschuren, Louk J M J; Westenberg, Herman G M

    2012-01-01

    Following the successful application of deep brain stimulation (DBS) in the treatment of Parkinson's disease and promising results in clinical trials for obsessive compulsive disorder and major depression, DBS is currently being tested in small patient-populations with eating disorders and addiction. However, in spite of its potential use in a broad spectrum of disorders, the mechanisms of action of DBS remain largely unclear and optimal neural targets for stimulation in several disorders have yet to be established. Thus, there is a great need to examine site-specific effects of DBS on a behavioural level and to understand how DBS may modulate pathological behaviour. In view of the possible application of DBS in the treatment of disorders characterized by impaired processing of reward and motivation, like addiction and eating disorders, we examined the effect of DBS of the nucleus accumbens (NAcc) on food-directed behavior. Rats were implanted with bilateral stimulation electrodes in one of three anatomically and functionally distinct sub-areas of the NAcc: the core, lateral shell (lShell) and medial shell (mShell). Subsequently, we studied the effects of DBS on food consumption, and the motivational and appetitive properties of food. The data revealed a functional dissociation between the lShell and mShell. DBS of the lShell reduced motivation to respond for sucrose under a progressive ratio schedule of reinforcement, mShell DBS, however, profoundly and selectively increased the intake of chow. DBS of the NAcc core did not alter any form of food-directed behavior studied. DBS of neither structure affected sucrose preference. These data indicate that the intake of chow and the motivation to work for palatable food can independently be modulated by DBS of subregions of the NAcc shell. As such, these findings provide important leads for the possible future application of DBS as a treatment for eating disorders such as anorexia nervosa.

  13. Deep-brain-stimulation does not impair deglutition in Parkinson's disease.

    PubMed

    Lengerer, Sabrina; Kipping, Judy; Rommel, Natalie; Weiss, Daniel; Breit, Sorin; Gasser, Thomas; Plewnia, Christian; Krüger, Rejko; Wächter, Tobias

    2012-08-01

    A large proportion of patients with Parkinson's disease develop dysphagia during the course of the disease. Dysphagia in Parkinson's disease affects different phases of deglutition, has a strong impact on quality of life and may cause severe complications, i.e., aspirational pneumonia. So far, little is known on how deep-brain-stimulation of the subthalamic nucleus influences deglutition in PD. Videofluoroscopic swallowing studies on 18 patients with Parkinson's disease, which had been performed preoperatively, and postoperatively with deep-brain-stimulation-on and deep-brain-stimulation-off, were analyzed retrospectively. The patients were examined in each condition with three consistencies (viscous, fluid and solid). The 'New Zealand index for multidisciplinary evaluation of swallowing (NZIMES) Subscale One' for qualitative and 'Logemann-MBS-Parameters' for quantitative evaluation were assessed. Preoperatively, none of the patients presented with clinically relevant signs of dysphagia. While postoperatively, the mean daily levodopa equivalent dosage was reduced by 50% and deep-brain-stimulation led to a 50% improvement in motor symptoms measured by the UPDRS III, no clinically relevant influence of deep-brain-stimulation-on swallowing was observed using qualitative parameters (NZIMES). However quantitative parameters (Logemann scale) found significant changes of pharyngeal parameters with deep-brain-stimulation-on as compared to preoperative condition and deep-brain-stimulation-off mostly with fluid consistency. In Parkinson patients without dysphagia deep-brain-stimulation of the subthalamic nucleus modulates the pharyngeal deglutition phase but has no clinically relevant influence on deglutition. Further studies are needed to test if deep-brain-stimulation is a therapeutic option for patients with swallowing disorders. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. Deep brain stimulation of the ventral hippocampus restores deficits in processing of auditory evoked potentials in a rodent developmental disruption model of schizophrenia

    PubMed Central

    Ewing, Samuel G.; Grace, Anthony A.

    2012-01-01

    Existing antipsychotic drugs are most effective at treating the positive symptoms of schizophrenia, but their relative efficacy is low and they are associated with considerable side effects. In this study deep brain stimulation of the ventral hippocampus was performed in a rodent model of schizophrenia (MAM-E17) in an attempt to alleviate one set of neurophysiological alterations observed in this disorder. Bipolar stimulating electrodes were fabricated and implanted, bilaterally, into the ventral hippocampus of rats. High frequency stimulation was delivered bilaterally via a custom-made stimulation device and both spectral analysis (power and coherence) of resting state local field potentials and amplitude of auditory evoked potential components during a standard inhibitory gating paradigm were examined. MAM rats exhibited alterations in specific components of the auditory evoked potential in the infralimbic cortex, the core of the nucleus accumbens, mediodorsal thalamic nucleus, and ventral hippocampus in the left hemisphere only. DBS was effective in reversing these evoked deficits in the infralimbic cortex and the mediodorsal thalamic nucleus of MAM-treated rats to levels similar to those observed in control animals. In contrast stimulation did not alter evoked potentials in control rats. No deficits or stimulation-induced alterations were observed in the prelimbic and orbitofrontal cortices, the shell of the nucleus accumbens or ventral tegmental area. These data indicate a normalization of deficits in generating auditory evoked potentials induced by a developmental disruption by acute high frequency, electrical stimulation of the ventral hippocampus. PMID:23269227

  15. Restoration of quinine-stimulated Fos-immunoreactive neurons in the central nucleus of the amygdala and gustatory cortex following reinnervation or cross-reinnervation of the lingual taste nerves in rats.

    PubMed

    King, Camille Tessitore; Garcea, Mircea; Spector, Alan C

    2014-08-01

    Remarkably, when lingual gustatory nerves are surgically rerouted to inappropriate taste fields in the tongue, some taste functions recover. We previously demonstrated that quinine-stimulated oromotor rejection reflexes and neural activity (assessed by Fos immunoreactivity) in subregions of hindbrain gustatory nuclei were restored if the posterior tongue, which contains receptor cells that respond strongly to bitter compounds, was cross-reinnervated by the chorda tympani nerve. Such functional recovery was not seen if instead, the anterior tongue, where receptor cells are less responsive to bitter compounds, was cross-reinnervated by the glossopharyngeal nerve, even though this nerve typically responds robustly to bitter substances. Thus, recovery depended more on the taste field being reinnervated than on the nerve itself. Here, the distribution of quinine-stimulated Fos-immunoreactive neurons in two taste-associated forebrain areas was examined in these same rats. In the central nucleus of the amygdala (CeA), a rostrocaudal gradient characterized the normal quinine-stimulated Fos response, with the greatest number of labeled cells situated rostrally. Quinine-stimulated neurons were found throughout the gustatory cortex, but a "hot spot" was observed in its anterior-posterior center in subregions approximating the dysgranular/agranular layers. Fos neurons here and in the rostral CeA were highly correlated with quinine-elicited gapes. Denervation of the posterior tongue eliminated, and its reinnervation by either nerve restored, numbers of quinine-stimulated labeled cells in the rostralmost CeA and in the subregion approximating the dysgranular gustatory cortex. These results underscore the remarkable plasticity of the gustatory system and also help clarify the functional anatomy of neural circuits activated by bitter taste stimulation. © 2014 Wiley Periodicals, Inc.

  16. Deep brain stimulation of the subthalamic nucleus improves temperature sensation in patients with Parkinson's disease.

    PubMed

    Maruo, Tomoyuki; Saitoh, Youichi; Hosomi, Koichi; Kishima, Haruhiko; Shimokawa, Toshio; Hirata, Masayuki; Goto, Tetsu; Morris, Shayne; Harada, Yu; Yanagisawa, Takufumi; Aly, Mohamed M; Yoshimine, Toshiki

    2011-04-01

    Patients with Parkinson's disease (PD) reportedly show deficits in sensory processing in addition to motor symptoms. However, little is known about the effects of bilateral deep brain stimulation of the subthalamic nucleus (STN-DBS) on temperature sensation as measured by quantitative sensory testing (QST). This study was designed to quantitatively evaluate the effects of STN-DBS on temperature sensation and pain in PD patients. We conducted a QST study comparing the effects of STN-DBS on cold sense thresholds (CSTs) and warm sense thresholds (WSTs) as well as on cold-induced and heat-induced pain thresholds (CPT and HPT) in 17 PD patients and 14 healthy control subjects. The CSTs and WSTs of patients were significantly smaller during the DBS-on mode when compared with the DBS-off mode (P<.001), whereas the CSTs and WSTs of patients in the DBS-off mode were significantly greater than those of healthy control subjects (P<.02). The CPTs and HPTs in PD patients were significantly larger on the more affected side than on the less affected side (P<.02). Because elevations in thermal sense and pain thresholds of QST are reportedly almost compatible with decreases in sensation, our findings confirm that temperature sensations may be disturbed in PD patients when compared with healthy persons and that STN-DBS can be used to improve temperature sensation in these patients. The mechanisms underlying our findings are not well understood, but improvement in temperature sensation appears to be a sign of modulation of disease-related brain network abnormalities. Copyright © 2010 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

  17. A Programmable High-Voltage Compliance Neural Stimulator for Deep Brain Stimulation in Vivo

    PubMed Central

    Gong, Cihun-Siyong Alex; Lai, Hsin-Yi; Huang, Sy-Han; Lo, Yu-Chun; Lee, Nicole; Chen, Pin-Yuan; Tu, Po-Hsun; Yang, Chia-Yen; Lin, James Chang-Chieh; Chen, You-Yin

    2015-01-01

    Deep brain stimulation (DBS) is one of the most effective therapies for movement and other disorders. The DBS neurosurgical procedure involves the implantation of a DBS device and a battery-operated neurotransmitter, which delivers electrical impulses to treatment targets through implanted electrodes. The DBS modulates the neuronal activities in the brain nucleus for improving physiological responses as long as an electric discharge above the stimulation threshold can be achieved. In an effort to improve the performance of an implanted DBS device, the device size, implementation cost, and power efficiency are among the most important DBS device design aspects. This study aims to present preliminary research results of an efficient stimulator, with emphasis on conversion efficiency. The prototype stimulator features high-voltage compliance, implemented with only a standard semiconductor process, without the use of extra masks in the foundry through our proposed circuit structure. The results of animal experiments, including evaluation of evoked responses induced by thalamic electrical stimuli with our fabricated chip, were shown to demonstrate the proof of concept of our design. PMID:26029954

  18. Cost-effectiveness of subthalmic nucleus deep brain stimulation for the treatment of advanced Parkinson disease in Hong Kong: a prospective study.

    PubMed

    Zhu, X L; Chan, Danny T M; Lau, Claire K Y; Poon, Wai S; Mok, Vincent C T; Chan, Anne Y Y; Wong, Lawrence K S; Yeung, Jonas H M; Leung, Michael C M; Tang, Venus Y H; Wong, Rosanna K M; Yeung, Carol

    2014-12-01

    Deep brain stimulation (DBS) is an effective but costly treatment for patients with advanced Parkinson disease (PD). This study examined the cost-effectiveness of DBS in relation to its improved effectiveness to help funding decision makers decide whether the treatment should be adopted. The incremental cost-effective ratio (ICER) per quality-adjusted life year has been benchmarked as being between US$50,000 and US$100,000 by US agencies, whereas it is less than €30,000 per quality-adjusted life year in Europe. To provide cost-effectiveness information of subthalamic nucleus DBS for patients with advanced PD. Direct medical expenses during the year before the DBS treatment were used to measure the baseline cost. Cost-effectiveness was measured by the ICER for the Unified Parkinson's Disease Rating Scale Part III and the ICER for the EuroQol Group's Health-Related Quality of Life measurement. Thirteen patients with advanced PD were recruited between January 2009 and January 2011. A 1-point improvement in the Unified Parkinson's Disease Rating Scale Part III score was associated with an ICER of US$926 in the first year and US$421 in the second year. A 1-point improvement on the EuroQol Group's Health-Related Quality of Life measurement was associated with an ICER of US$123,110 in the first year and US$62,846 in the second year. Cost-effectiveness of subthalamic nucleus DBS for treatment of advanced PD is greater during a 2-year period than 1 year only. These results can be used as a reference for the use of DBS for PD in a region with public health financing. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Dopamine or opioid stimulation of nucleus accumbens similarly amplify cue-triggered 'wanting' for reward: entire core and medial shell mapped as substrates for PIT enhancement.

    PubMed

    Peciña, Susana; Berridge, Kent C

    2013-05-01

    Pavlovian cues [conditioned stimulus (CS+)] often trigger intense motivation to pursue and consume related reward [unconditioned stimulus (UCS)]. But cues do not always trigger the same intensity of motivation. Encountering a reward cue can be more tempting on some occasions than on others. What makes the same cue trigger more intense motivation to pursue reward on a particular encounter? The answer may be the level of incentive salience ('wanting') that is dynamically generated by mesocorticolimbic brain systems, influenced especially by dopamine and opioid neurotransmission in the nucleus accumbens (NAc) at that moment. We tested the ability of dopamine stimulation (by amphetamine microinjection) vs. mu opioid stimulation [by d-Ala, nMe-Phe, Glyol-enkephalin (DAMGO) microinjection] of either the core or shell of the NAc to amplify cue-triggered levels of motivation to pursue sucrose reward, measured with a Pavlovian-Instrumental Transfer (PIT) procedure, a relatively pure assay of incentive salience. Cue-triggered 'wanting' in PIT was enhanced by amphetamine or DAMGO microinjections equally, and also equally at nearly all sites throughout the entire core and medial shell (except for a small far-rostral strip of shell). NAc dopamine/opioid stimulations specifically enhanced CS+ ability to trigger phasic peaks of 'wanting' to obtain UCS, without altering baseline efforts when CS+ was absent. We conclude that dopamine/opioid stimulation throughout nearly the entire NAc can causally amplify the reactivity of mesocorticolimbic circuits, and so magnify incentive salience or phasic UCS 'wanting' peaks triggered by a CS+. Mesolimbic amplification of incentive salience may explain why a particular cue encounter can become irresistibly tempting, even when previous encounters were successfully resisted before. © 2013 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  20. Effects of Intralaminar Thalamic Stimulation on Language Functions

    ERIC Educational Resources Information Center

    Bhatnagar, Subhash C.; Mandybur, George T.

    2005-01-01

    Fifteen neurosurgical subjects, who were undergoing thalamic chronic electrode implants as a treatment for dyskinesia and chronic pain, were evaluated on a series of neurolinguistic functions to determine if the stimulation of the centromedianum nucleus of the thalamus affected language and cognitive processing. Analysis of the data revealed that…

  1. Different Classes of Glutamate Receptors Mediate Distinct Behaviors in a Single Brainstem Nucleus

    NASA Astrophysics Data System (ADS)

    Dye, John; Heiligenberg, Walter; Keller, Clifford H.; Kawasaki, Masashi

    1989-11-01

    We have taken advantage of the increasing understanding of glutamate neuropharmacology to probe mechanisms of well-defined vertebrate behaviors. Here we report a set of experiments that suggests distinct roles for two major classes of glutamate receptors in a discrete premotor nucleus of the brainstem. The medullary pacemaker nucleus of weakly electric fish is an endogenous oscillator that controls the electric organ discharge (EOD). Its regular frequency of firing is modulated during several distinct behaviors. The pacemaker nucleus continues firing regularly when isolated in vitro, and modulatory behaviors can be reproduced by stimulating the descending input pathway. Glutamate agonists applied to the pacemaker in vitro produced increases in frequency, while glutamate antagonists selectively blocked stimulus-induced modulations. Experiments with glutamate antagonists in the intact animal resulted in specific effects on two well-characterized behaviors. Our data indicate that these behaviors are separately mediated in the pacemaker by receptors displaying characteristics of the kainate/quisqualate and N-methyl-D-aspartate subtypes of glutamate receptor, respectively.

  2. [Ultrasonic measurements of fetal thalamus, caudate nucleus and lenticular nucleus in prenatal diagnosis].

    PubMed

    Yang, Ruiqi; Wang, Fei; Zhang, Jialing; Zhu, Chonglei; Fan, Limei

    2015-05-19

    To establish the reference values of thalamus, caudate nucleus and lenticular nucleus diameters through fetal thalamic transverse section. A total of 265 fetuses at our hospital were randomly selected from November 2012 to August 2014. And the transverse and length diameters of thalamus, caudate nucleus and lenticular nucleus were measured. SPSS 19.0 statistical software was used to calculate the regression curve of fetal diameter changes and gestational weeks of pregnancy. P < 0.05 was considered as having statistical significance. The linear regression equation of fetal thalamic length diameter and gestational week was: Y = 0.051X+0.201, R = 0.876, linear regression equation of thalamic transverse diameter and fetal gestational week was: Y = 0.031X+0.229, R = 0.817, linear regression equation of fetal head of caudate nucleus length diameter and gestational age was: Y = 0.033X+0.101, R = 0.722, linear regression equation of fetal head of caudate nucleus transverse diameter and gestational week was: R = 0.025 - 0.046, R = 0.711, linear regression equation of fetal lentiform nucleus length diameter and gestational week was: Y = 0.046+0.229, R = 0.765, linear regression equation of fetal lentiform nucleus diameter and gestational week was: Y = 0.025 - 0.05, R = 0.772. Ultrasonic measurement of diameter of fetal thalamus caudate nucleus, and lenticular nucleus through thalamic transverse section is simple and convenient. And measurements increase with fetal gestational weeks and there is linear regression relationship between them.

  3. Effects of deep brain stimulation of the subthalamic nucleus on inhibitory and executive control over prepotent responses in Parkinson's disease

    PubMed Central

    Jahanshahi, Marjan

    2013-01-01

    Inhibition of inappropriate, habitual or prepotent responses is an essential component of executive control and a cornerstone of self-control. Via the hyperdirect pathway, the subthalamic nucleus (STN) receives inputs from frontal areas involved in inhibition and executive control. Evidence is reviewed from our own work and the literature suggesting that in Parkinson's disease (PD), deep brain stimulation (DBS) of the STN has an impact on executive control during attention-demanding tasks or in situations of conflict when habitual or prepotent responses have to be inhibited. These results support a role for the STN in an inter-related set of processes: switching from automatic to controlled processing, inhibitory and executive control, adjusting response thresholds and influencing speed-accuracy trade-offs. Such STN DBS-induced deficits in inhibitory and executive control may contribute to some of the psychiatric problems experienced by a proportion of operated cases after STN DBS surgery in PD. However, as no direct evidence for such a link is currently available, there is a need to provide direct evidence for such a link between STN DBS-induced deficits in inhibitory and executive control and post-surgical psychiatric complications experienced by operated patients. PMID:24399941

  4. Meta-analysis comparing deep brain stimulation of the globus pallidus and subthalamic nucleus to treat advanced Parkinson disease.

    PubMed

    Liu, Yi; Li, Weina; Tan, Changhong; Liu, Xi; Wang, Xin; Gui, Yuejiang; Qin, Lu; Deng, Fen; Hu, Changlin; Chen, Lifen

    2014-09-01

    Deep brain stimulation (DBS) is the surgical procedure of choice for patients with advanced Parkinson disease (PD). The globus pallidus internus (GPi) and the subthalamic nucleus (STN) are commonly targeted by this procedure. The purpose of this meta-analysis was to compare the efficacy of DBS in each region. MEDLINE/PubMed, EMBASE, Web of Knowledge, and the Cochrane Library were searched for English-language studies published before April 2013. of studies investigating the efficacy and clinical outcomes of DBS of the GPi and STN for PD were analyzed. Six eligible trials containing a total of 563 patients were included in the analysis. Deep brain stimulation of the GPi or STN equally improved motor function, measured by the Unified Parkinson's Disease Rating Scale Section III (UPDRSIII) (motor section, for patients in on- and off-medication phases), within 1 year postsurgery. The change score for the on-medication phase was 0.68 (95% CI - 2.12 to 3.47, p > 0.05; 5 studies, 518 patients) and for the off-medication phase was 1.83 (95% CI - 3.12 to 6.77, p > 0.05; 5 studies, 518 patients). The UPDRS Section II (activities of daily living) scores for patients on medication improved equally in both DBS groups (p = 0.97). STN DBS allowed medication dosages to be reduced more than GPi DBS (95% CI 129.27-316.64, p < 0.00001; 5 studies, 540 patients). Psychiatric symptoms, measured by Beck Depression Inventory, 2nd edition scores, showed greater improvement from baseline after GPi DBS than after STN DBS (standardized mean difference -2.28, 95% CI -3.73 to -0.84, p = 0.002; 3 studies, 382 patients). GPi and STN DBS improve motor function and activities of daily living for PD patients. Differences in therapeutic efficacy for PD were not observed between the 2 procedures. STN DBS allowed greater reduction in medication for patients, whereas GPi DBS provided greater relief from psychiatric symptoms. An understanding of other symptomatic aspects of targeting each region and long

  5. Functionalized active-nucleus complex sensor

    DOEpatents

    Pines, Alexander; Wemmer, David E.; Spence, Megan; Rubin, Seth

    2003-11-25

    A functionalized active-nucleus complex sensor that selectively associates with one or more target species, and a method for assaying and screening for one or a plurality of target species utilizing one or a plurality of functionalized active-nucleus complexes with at least two of the functionalized active-nucleus complexes having an attraction affinity to different corresponding target species. The functionalized active-nucleus complex has an active-nucleus and a targeting carrier. The method involves functionalizing an active-nucleus, for each functionalized active-nucleus complex, by incorporating the active-nucleus into a macromolucular or molecular complex that is capable of binding one of the target species and then bringing the macromolecular or molecular complexes into contact with the target species and detecting the occurrence of or change in a nuclear magnetic resonance signal from each of the active-nuclei in each of the functionalized active-nucleus complexes.

  6. Deep brain stimulation of the ventral hippocampus restores deficits in processing of auditory evoked potentials in a rodent developmental disruption model of schizophrenia.

    PubMed

    Ewing, Samuel G; Grace, Anthony A

    2013-02-01

    Existing antipsychotic drugs are most effective at treating the positive symptoms of schizophrenia but their relative efficacy is low and they are associated with considerable side effects. In this study deep brain stimulation of the ventral hippocampus was performed in a rodent model of schizophrenia (MAM-E17) in an attempt to alleviate one set of neurophysiological alterations observed in this disorder. Bipolar stimulating electrodes were fabricated and implanted, bilaterally, into the ventral hippocampus of rats. High frequency stimulation was delivered bilaterally via a custom-made stimulation device and both spectral analysis (power and coherence) of resting state local field potentials and amplitude of auditory evoked potential components during a standard inhibitory gating paradigm were examined. MAM rats exhibited alterations in specific components of the auditory evoked potential in the infralimbic cortex, the core of the nucleus accumbens, mediodorsal thalamic nucleus, and ventral hippocampus in the left hemisphere only. DBS was effective in reversing these evoked deficits in the infralimbic cortex and the mediodorsal thalamic nucleus of MAM-treated rats to levels similar to those observed in control animals. In contrast stimulation did not alter evoked potentials in control rats. No deficits or stimulation-induced alterations were observed in the prelimbic and orbitofrontal cortices, the shell of the nucleus accumbens or ventral tegmental area. These data indicate a normalization of deficits in generating auditory evoked potentials induced by a developmental disruption by acute high frequency, electrical stimulation of the ventral hippocampus. Copyright © 2012 Elsevier B.V. All rights reserved.

  7. Subthalamic Nucleus Deep Brain Stimulation in Early Stage Parkinson's Disease Is Not Associated with Increased Body Mass Index

    PubMed Central

    Hacker, Mallory L.; Turchan, Maxim; Molinari, Anna L.; Currie, Amanda D.

    2017-01-01

    Previous studies suggest that deep brain stimulation of the subthalamic nucleus (STN-DBS) for Parkinson's disease (PD) leads to weight gain. This study analyzes changes in body mass index (BMI) in 29 subjects from a prospective, single-blind trial of DBS in early stage PD (age 50–75, Hoehn & Yahr stage II off medication, treated with antiparkinsonian medications for ≥6 months but <4 years, and without a history of motor fluctuations, dyskinesias, or dementia). Subjects were randomized to DBS plus optimal drug therapy (DBS+ODT; n = 15) or ODT (n = 14) and followed for 24 months. Weight and height were recorded at baseline and each follow-up visit and used to calculate BMI. BMIs were compared within and between groups using nonparametric t-tests. Mean BMI at baseline was 29.7 in the ODT group and 32.3 in the DBS+ODT group (p > 0.05). BMI change over two years was not different between the groups (p = 0.62, ODT = −0.89; DBS+ODT = −0.17). This study suggests that STN-DBS is not associated with weight gain in subjects with early stage PD. This finding will be tested in an upcoming FDA-approved phase III multicenter, randomized, double-blind, placebo-controlled, pivotal clinical trial evaluating DBS in early stage PD (ClinicalTrials.gov identifier NCT00282152). PMID:28676842

  8. Subthalamic Nucleus Deep Brain Stimulation in Early Stage Parkinson's Disease Is Not Associated with Increased Body Mass Index.

    PubMed

    Millan, Sarah H; Hacker, Mallory L; Turchan, Maxim; Molinari, Anna L; Currie, Amanda D; Charles, David

    2017-01-01

    Previous studies suggest that deep brain stimulation of the subthalamic nucleus (STN-DBS) for Parkinson's disease (PD) leads to weight gain. This study analyzes changes in body mass index (BMI) in 29 subjects from a prospective, single-blind trial of DBS in early stage PD (age 50-75, Hoehn & Yahr stage II off medication, treated with antiparkinsonian medications for ≥6 months but <4 years, and without a history of motor fluctuations, dyskinesias, or dementia). Subjects were randomized to DBS plus optimal drug therapy (DBS+ODT; n = 15) or ODT ( n = 14) and followed for 24 months. Weight and height were recorded at baseline and each follow-up visit and used to calculate BMI. BMIs were compared within and between groups using nonparametric t -tests. Mean BMI at baseline was 29.7 in the ODT group and 32.3 in the DBS+ODT group ( p > 0.05). BMI change over two years was not different between the groups ( p = 0.62, ODT = -0.89; DBS+ODT = -0.17). This study suggests that STN-DBS is not associated with weight gain in subjects with early stage PD. This finding will be tested in an upcoming FDA-approved phase III multicenter, randomized, double-blind, placebo-controlled, pivotal clinical trial evaluating DBS in early stage PD (ClinicalTrials.gov identifier NCT00282152).

  9. Optogenetic Stimulation of Arcuate Nucleus Kiss1 Neurons Reveals a Steroid-Dependent Glutamatergic Input to POMC and AgRP Neurons in Male Mice

    PubMed Central

    Nestor, Casey C; Qiu, Jian; Padilla, Stephanie L.; Zhang, Chunguang; Bosch, Martha A.; Fan, Wei; Aicher, Sue A.; Palmiter, Richard D.

    2016-01-01

    Kisspeptin (Kiss1) neurons are essential for reproduction, but their role in the control of energy balance and other homeostatic functions remains unclear. Proopiomelanocortin (POMC) and agouti-related peptide (AgRP) neurons, located in the arcuate nucleus (ARC) of the hypothalamus, integrate numerous excitatory and inhibitory inputs to ultimately regulate energy homeostasis. Given that POMC and AgRP neurons are contacted by Kiss1 neurons in the ARC (Kiss1ARC) and they express androgen receptors, Kiss1ARC neurons may mediate the orexigenic action of testosterone via POMC and/or AgRP neurons. Quantitative PCR analysis of pooled Kiss1ARC neurons revealed that mRNA levels for Kiss1 and vesicular glutamate transporter 2 were higher in castrated male mice compared with gonad-intact males. Single-cell RT-PCR analysis of yellow fluorescent protein (YFP) ARC neurons harvested from males injected with AAV1-EF1α-DIO-ChR2:YFP revealed that 100% and 88% expressed mRNAs for Kiss1 and vesicular glutamate transporter 2, respectively. Whole-cell, voltage-clamp recordings from nonfluorescent postsynaptic ARC neurons showed that low frequency photo-stimulation (0.5 Hz) of Kiss1-ChR2:YFP neurons elicited a fast glutamatergic inward current in POMC and AgRP neurons. Paired-pulse, photo-stimulation revealed paired-pulse depression, which is indicative of greater glutamate release, in the castrated male mice compared with gonad-intact male mice. Group I and group II metabotropic glutamate receptor agonists depolarized and hyperpolarized POMC and AgRP neurons, respectively, which was mimicked by high frequency photo-stimulation (20 Hz) of Kiss1ARC neurons. Therefore, POMC and AgRP neurons receive direct steroid- and frequency-dependent glutamatergic synaptic input from Kiss1ARC neurons in male mice, which may be a critical pathway for Kiss1 neurons to help coordinate energy homeostasis and reproduction. PMID:27093227

  10. An examination of the effects of subthalamic nucleus inhibition or μ-opioid receptor stimulation on food-directed motivation in the non-deprived rat

    PubMed Central

    Pratt, Wayne E.; Choi, Eugene; Guy, Elizabeth G.

    2012-01-01

    The subthalamic nucleus (STN) serves important functions in regulating movement, cognition, and motivation and is connected with cortical and basal ganglia circuits that process reward and reinforcement. In order to further examine the role of the STN on motivation toward food in non-deprived rats, these experiments studied the effects of pharmacological inhibition or μ-opioid receptor stimulation of the STN on the 2-hr intake of a sweetened fat diet, the amount of work exerted to earn sucrose on a progressive ratio 2 (PR-2) schedule of reinforcement, and performance on a differential reinforcement of low-rate responding (DRL) schedule for sucrose reward. Separate behavioral groups (N = 6–9) were tested following bilateral inhibition of the STN with the GABAA receptor agonist muscimol (at 0–5 ng/0.5 μl/side) or following μ-opioid receptor stimulation with the agonist D-Ala2, N-MePhe4, Gly-ol-enkephalin (DAMGO; at 0, 0.025 or 0.25 μg/0.5 μl/side). Although STN inhibition increased ambulatory behavior during 2-hr feeding sessions, it did not significantly alter intake of the sweetened fat diet. STN inhibition also did not affect the breakpoint for sucrose pellets during a 1-hr PR-2 reinforcement schedule or impact the number of reinforcers earned on a 1-hr DRL-20 sec reinforcement schedule in non-deprived rats. In contrast, STN μ-opioid receptor stimulation significantly increased feeding on the palatable diet and reduced the reinforcers earned on a DRL-20 schedule, although DAMGO microinfusions had no effect on PR-2 performance. These data suggest that STN inhibition does not enhance incentive motivation for food in the absence of food restriction and that STN μ-opioid receptors play an important and unique role in motivational processes. PMID:22391117

  11. Deep brain stimulation of the subthalamic nucleus in obsessive-compulsive disorder: Neuroanatomical and pathophysiological considerations.

    PubMed

    Mulders, A E P; Plantinga, B R; Schruers, K; Duits, A; Janssen, M L F; Ackermans, L; Leentjens, A F G; Jahanshahi, A; Temel, Y

    2016-12-01

    Obsessive-compulsive disorder (OCD) is among the most disabling chronic psychiatric disorders and has a significant negative impact on multiple domains of quality of life. For patients suffering from severe refractory OCD, deep brain stimulation (DBS) of the subthalamic nucleus (STN) has been applied. Reviewing the literature of the last years we believe that through its central position within the cortico-basal ganglia-thalamocortical circuits, the STN has a coordinating role in decision-making and action-selection mechanisms. Dysfunctional information-processing at the level of the STN is responsible for some of the core symptoms of OCD. Research confirms an electrophysiological dysfunction in the associative and limbic (non-motor) parts of the STN. Compared to Parkinson׳s disease patients, STN neurons in OCD exhibit a lower firing rate, less frequent but longer bursts, increased burst activity in the anterior ventromedial area, an asymmetrical left-sided burst distribution, and a predominant oscillatory activity in the δ-band. Moreover, there is direct evidence for the involvement of the STN in both checking behavior and OCD symptoms, which are both related to changes in electrophysiological activity in the non-motor STN. Through a combination of mechanisms, DBS of the STN seems to interrupt the disturbed information-processing, leading to a normalization of connectivity within the cortico-basal ganglia-thalamocortical circuits and consequently to a reduction in symptoms. In conclusion, based on the STN׳s strategic position within cortico-basal ganglia-thalamocortical circuits and its involvement in action-selection mechanisms that are responsible for some of the core symptoms of OCD, the STN is a mechanism-based target for DBS in OCD. Copyright © 2016 Elsevier B.V. and ECNP. All rights reserved.

  12. PI3K in the ventromedial hypothalamic nucleus mediates estrogenic actions on energy expenditure in female mice

    USDA-ARS?s Scientific Manuscript database

    Estrogens act in the ventromedial hypothalamic nucleus (VMH) to regulate body weight homeostasis. However, the molecular mechanisms underlying these estrogenic effects are unknown. We show that activation of estrogen receptor-a (ERa) stimulates neural firing of VMH neurons expressing ERa, and these ...

  13. Subthalamic nucleus deep brain stimulation improves deglutition in Parkinson's disease.

    PubMed

    Ciucci, Michelle R; Barkmeier-Kraemer, Julie M; Sherman, Scott J

    2008-04-15

    Relatively little is known about the role of the basal ganglia in human deglutition. Deep brain stimulation (DBS) affords us a model for examining deglutition in humans with known impairment of the basal ganglia. The purpose of this study was to examine the effects of subthalamic nuclei (STN) DBS on the oral and pharyngeal stages of deglutition in individuals with Parkinson's Disease (PD). It was hypothesized that DBS would be associated with improved deglutition. Within participant, comparisons were made between DBS in the ON and OFF conditions using the dependent variables: pharyngeal transit time, maximal hyoid bone excursion, oral total composite score, and pharyngeal total composite score. Significant improvement occurred for the pharyngeal composite score and pharyngeal transit time in the DBS ON condition compared with DBS OFF. Stimulation of the STN may excite thalamocortical or brainstem targets to sufficiently overcome the bradykinesia/hypokinesia associated with PD and return some pharyngeal stage motor patterns to performance levels approximating those of "normal" deglutition. However, the degree of hyoid bone excursion and oral stage measures did not improve, suggesting that these motor acts may be under the control of different sensorimotor pathways within the basal ganglia. 2007 Movement Disorder Society

  14. Differential effects of deep brain stimulation on verbal fluency.

    PubMed

    Ehlen, Felicitas; Schoenecker, Thomas; Kühn, Andrea A; Klostermann, Fabian

    2014-07-01

    We aimed at gaining insights into principles of subcortical lexical processing. Therefore, effects of deep brain stimulation (DBS) in different target structures on verbal fluency (VF) were tested. VF was assessed with active vs. inactivated DBS in 13 and 14 patients with DBS in the vicinity of the thalamic ventral intermediate nucleus (VIM) and, respectively, of the subthalamic nucleus (STN). Results were correlated to electrode localizations in postoperative MRI, and compared to those of 12 age-matched healthy controls. Patients' VF performance was generally below normal. However, while activation of DBS in the vicinity of VIM provoked marked VF decline, it induced subtle phonemic VF enhancement in the vicinity of STN. The effects correlated with electrode localizations in left hemispheric stimulation sites. The results show distinct dependencies of VF on DBS in the vicinity of VIM vs. STN. Particular risks for deterioration occur in patients with relatively ventromedial thalamic electrodes. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. Paraventricular Nucleus Modulates Excitatory Cardiovascular Reflexes during Electroacupuncture

    PubMed Central

    Tjen-A-Looi, Stephanie C.; Guo, Zhi-Ling; Fu, Liang-Wu; Longhurst, John C.

    2016-01-01

    The paraventricular nucleus (PVN) regulates sympathetic outflow and blood pressure. Somatic afferent stimulation activates neurons in the hypothalamic PVN. Parvocellular PVN neurons project to sympathoexcitatory cardiovascular regions of the rostral ventrolateral medulla (rVLM). Electroacupuncture (EA) stimulates the median nerve (P5-P6) to modulate sympathoexcitatory responses. We hypothesized that the PVN and its projections to the rVLM participate in the EA-modulation of sympathoexcitatory cardiovascular responses. Cats were anesthetized and ventilated. Heart rate and mean blood pressure were monitored. Application of bradykinin every 10-min on the gallbladder induced consistent pressor reflex responses. Thirty-min of bilateral EA stimulation at acupoints P5-P6 reduced the pressor responses for at least 60-min. Inhibition of the PVN with naloxone reversed the EA-inhibition. Responses of cardiovascular barosensitive rVLM neurons evoked by splanchnic nerve stimulation were reduced by EA and then restored with opioid receptor blockade in the PVN. EA at P5-P6 decreased splanchnic evoked activity of cardiovascular barosensitive PVN neurons that also project directly to the rVLM. PVN neurons labeled with retrograde tracer from rVLM were co-labeled with μ-opioid receptors and juxtaposed to endorphinergic fibers. Thus, the PVN and its projection to rVLM are important in processing acupuncture modulation of elevated blood pressure responses through a PVN opioid mechanism. PMID:27181844

  16. Subthalamic nucleus stimulation affects theory of mind network: a PET study in Parkinson's disease.

    PubMed

    Péron, Julie; Le Jeune, Florence; Haegelen, Claire; Dondaine, Thibaut; Drapier, Dominique; Sauleau, Paul; Reymann, Jean-Michel; Drapier, Sophie; Rouaud, Tiphaine; Millet, Bruno; Vérin, Marc

    2010-03-29

    There appears to be an overlap between the limbic system, which is modulated by subthalamic nucleus (STN) deep brain stimulation (DBS) in Parkinson's disease (PD), and the brain network that mediates theory of mind (ToM). Accordingly, the aim of the present study was to investigate the effects of STN DBS on ToM of PD patients and to correlate ToM modifications with changes in glucose metabolism. To this end, we conducted (18)FDG-PET scans in 13 PD patients in pre- and post-STN DBS conditions and correlated changes in their glucose metabolism with modified performances on the Eyes test, a visual ToM task requiring them to describe thoughts or feelings conveyed by photographs of the eye region. Postoperative PD performances on this emotion recognition task were significantly worse than either preoperative PD performances or those of healthy controls (HC), whereas there was no significant difference between preoperative PD and HC. Conversely, PD patients in the postoperative condition performed within the normal range on the gender attribution task included in the Eyes test. As far as the metabolic results are concerned, there were correlations between decreased cerebral glucose metabolism and impaired ToM in several cortical areas: the bilateral cingulate gyrus (BA 31), right middle frontal gyrus (BA 8, 9 and 10), left middle frontal gyrus (BA 6), temporal lobe (fusiform gyrus, BA 20), bilateral parietal lobe (right BA 3 and right and left BA 7) and bilateral occipital lobe (BA 19). There were also correlations between increased cerebral glucose metabolism and impaired ToM in the left superior temporal gyrus (BA 22), left inferior frontal gyrus (BA 13 and BA 47) and right inferior frontal gyrus (BA 47). All these structures overlap with the brain network that mediates ToM. These results seem to confirm that STN DBS hinders the ability to infer the mental states of others and modulates a distributed network known to subtend ToM.

  17. Subthalamic Nucleus Deep Brain Stimulation for Parkinson Disease in Hong Kong: A Prospective Territory-Wide 2-Year Follow-Up Study.

    PubMed

    Chan, Danny T M; Zhu, Cannon X L; Lau, Claire K Y; Poon, Tak L; Cheung, Fung C; Lee, Michael; Taw, Benedict; Hung, Kwan N; Choi, Priscilla; AuYeung, Mandy; Chan, Germaine; Cheung, Yuk F; Chan, Anne Y Y; Yeung, Jonas H M; Mok, Vincent C T; Poon, Wai S

    2016-09-01

    We assessed the effects of bilateral subthalamic nucleus (STN) deep brain stimulation (DBS) in patients with Parkinson disease at the 1-year and 2-year follow-up evaluations. Unified Parkinson's Disease Rating Scale (UPDRS) motor score at "off" medication ("on" DBS) and quality-of-life assessments (39-item Parkinson's Disease Questionnaire [PDQ-39]) were conducted. The percentage of awake "on" time and awake "off" time and levodopa requirement were also assessed. A 2-year prospective study was conducted of 25 consecutive patients from 3 DBS referral centers in Hong Kong. The patients were treated with bilateral stimulation of the STN. Assessments were performed at 1 year and 2 years after DBS and were compared with the baseline. The 2-year outcome assessments were completed by 18 patients. The mean UPDRS motor score improvement was 57% in the first year and 45% in the second year. PDQ-39 showed significant improvement in quality of life for 2 consecutive years. The levodopa requirement decreased 63% in the first year and 55.9% in the second year. The awake "on" time was doubled in the first year and sustained in the second year. Awake "off" time was reduced from 28.1% to 5.9% in the first year and returned to 10.6% in the second year. Improvement of UPDRS motor score, reduction in awake "off" time, and decrease of daily levodopa dosage all were main factors correlated with the improvement in PDQ-39 summary index. The effects of STN DBS in patients with Parkinson disease in Hong Kong were satisfactory. The results showed that reduction in UPDRS motor score, awake "off"-time, and daily levodopa dosage were the major drivers of overall improvement in PDQ-39. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Caffeine Induces a Stimulant Effect and Increases Dopamine Release in the Nucleus Accumbens Shell Through the Pulmonary Inhalation Route of Administration in Rats.

    PubMed

    Galvalisi, Martín; Prieto, José Pedro; Martínez, Marcela; Abin-Carriquiry, Juan Andrés; Scorza, Cecilia

    2017-01-01

    Oral, intraperitoneal, or intravenous have been the common routes of administration used to study the behavioral and neurochemical pharmacology of caffeine, one of the most widely used psychoactive substances worldwide. We have reported that caffeine is an active adulterant frequently found in coca-paste (CP)-seized samples, a highly addictive form of smokable cocaine. The role of caffeine in the psychostimulant and neurochemical effects induced by CP remains under study. No preclinical animal studies have been performed so far to characterize the effects of caffeine when it is administered through the pulmonary inhalation route. Caffeine (10, 25, and 50 mg) was volatilized and rats were exposed to one inhalation session of its vapor. The stimulant effect was automatically recorded and plasmatic levels of caffeine were measured. Caffeine capability (50 mg) to increase extracellular dopamine (DA) levels in nucleus accumbens shell was also studied by in vivo microdialysis in non-anesthetized animals. A dose-dependent stimulant effect induced by volatilized caffeine was observed and this effect was directly related with caffeine plasmatic levels. A significant increase in the extracellular DA was achieved after 50 mg of volatilized caffeine exposure. This is the first report showing pharmacological acute effects of caffeine through the pulmonary inhalation route of administration and suggests that this could be a condition under which caffeine can elevate its weak reinforcing effect and even enhance the psychostimulant effect and abuse liability of smokable adulterated psychostimulant drugs.

  19. The area postrema (AP) and the parabrachial nucleus (PBN) are important sites for salmon calcitonin (sCT) to decrease evoked phasic dopamine release in the nucleus accumbens (NAc).

    PubMed

    Whiting, Lynda; McCutcheon, James E; Boyle, Christina N; Roitman, Mitchell F; Lutz, Thomas A

    2017-07-01

    The pancreatic hormone amylin and its agonist salmon calcitonin (sCT) act via the area postrema (AP) and the lateral parabrachial nucleus (PBN) to reduce food intake. Investigations of amylin and sCT signaling in the ventral tegmental area (VTA) and nucleus accumbens (NAc) suggest that the eating inhibitory effect of amylin is, in part, mediated through the mesolimbic 'reward' pathway. Indeed, administration of the sCT directly to the VTA decreased phasic dopamine release (DA) in the NAc. However, it is not known if peripheral amylin modulates the mesolimbic system directly or whether this occurs via the AP and PBN. To determine whether and how peripheral amylin or sCT affect mesolimbic reward circuitry we utilized fast scan cyclic voltammetry under anesthesia to measure phasic DA release in the NAc evoked by electrical stimulation of the VTA in intact, AP lesioned and bilaterally PBN lesioned rats. Amylin (50μg/kg i.p.) did not change phasic DA responses compared to saline control rats. However, sCT (50μg/kg i.p.) decreased evoked DA release to VTA-stimulation over 1h compared to saline treated control rats. Further investigations determined that AP and bilateral PBN lesions abolished the ability of sCT to suppress evoked phasic DA responses to VTA-stimulation. These findings implicate the AP and the PBN as important sites for peripheral sCT to decrease evoked DA release in the NAc and suggest that these nuclei may influence hedonic and motivational processes to modulate food intake. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Movement-Related Discharge in the Macaque Globus Pallidus during High-Frequency Stimulation of the Subthalamic Nucleus

    PubMed Central

    Zimnik, Andrew J.; Nora, Gerald J.; Desmurget, Michel

    2015-01-01

    Deep brain stimulation (DBS) of the subthalamic nucleus (STN-DBS) has largely replaced ablative therapies for Parkinson's disease. Because of the similar efficacies of the two treatments, it has been proposed that DBS acts by creating an “informational lesion,” whereby pathologic neuronal firing patterns are replaced by low-entropy, stimulus-entrained firing patterns. The informational lesion hypothesis, in its current form, states that DBS blocks the transmission of all information from the basal ganglia, including both pathologic firing patterns and normal, task-related modulations in activity. We tested this prediction in two healthy rhesus macaques by recording single-unit spiking activity from the globus pallidus (232 neurons) while the animals completed choice reaction time reaching movements with and without STN-DBS. Despite strong effects of DBS on the activity of most pallidal cells, reach-related modulations in firing rate were equally prevalent in the DBS-on and DBS-off states. This remained true even when the analysis was restricted to cells affected significantly by DBS. In addition, the overall form and timing of perimovement modulations in firing rate were preserved between DBS-on and DBS-off states in the majority of neurons (66%). Active movement and DBS had largely additive effects on the firing rate of most neurons, indicating an orthogonal relationship in which both inputs contribute independently to the overall firing rate of pallidal neurons. These findings suggest that STN-DBS does not act as an indiscriminate informational lesion but rather as a filter that permits task-related modulations in activity while, presumably, eliminating the pathological firing associated with parkinsonism. PMID:25740526

  1. Deep Brain Stimulation Reveals a Dissociation of Consummatory and Motivated Behaviour in the Medial and Lateral Nucleus Accumbens Shell of the Rat

    PubMed Central

    van der Plasse, Geoffrey; Schrama, Regina; van Seters, Sebastiaan P.; Vanderschuren, Louk J. M. J.

    2012-01-01

    Following the successful application of deep brain stimulation (DBS) in the treatment of Parkinson's disease and promising results in clinical trials for obsessive compulsive disorder and major depression, DBS is currently being tested in small patient-populations with eating disorders and addiction. However, in spite of its potential use in a broad spectrum of disorders, the mechanisms of action of DBS remain largely unclear and optimal neural targets for stimulation in several disorders have yet to be established. Thus, there is a great need to examine site-specific effects of DBS on a behavioural level and to understand how DBS may modulate pathological behaviour. In view of the possible application of DBS in the treatment of disorders characterized by impaired processing of reward and motivation, like addiction and eating disorders, we examined the effect of DBS of the nucleus accumbens (NAcc) on food-directed behavior. Rats were implanted with bilateral stimulation electrodes in one of three anatomically and functionally distinct sub-areas of the NAcc: the core, lateral shell (lShell) and medial shell (mShell). Subsequently, we studied the effects of DBS on food consumption, and the motivational and appetitive properties of food. The data revealed a functional dissociation between the lShell and mShell. DBS of the lShell reduced motivation to respond for sucrose under a progressive ratio schedule of reinforcement, mShell DBS, however, profoundly and selectively increased the intake of chow. DBS of the NAcc core did not alter any form of food-directed behavior studied. DBS of neither structure affected sucrose preference. These data indicate that the intake of chow and the motivation to work for palatable food can independently be modulated by DBS of subregions of the NAcc shell. As such, these findings provide important leads for the possible future application of DBS as a treatment for eating disorders such as anorexia nervosa. PMID:22428054

  2. Multiple-source current steering in subthalamic nucleus deep brain stimulation for Parkinson's disease (the VANTAGE study): a non-randomised, prospective, multicentre, open-label study.

    PubMed

    Timmermann, Lars; Jain, Roshini; Chen, Lilly; Maarouf, Mohamed; Barbe, Michael T; Allert, Niels; Brücke, Thomas; Kaiser, Iris; Beirer, Sebastian; Sejio, Fernando; Suarez, Esther; Lozano, Beatriz; Haegelen, Claire; Vérin, Marc; Porta, Mauro; Servello, Domenico; Gill, Steven; Whone, Alan; Van Dyck, Nic; Alesch, Francois

    2015-07-01

    High-frequency deep brain stimulation (DBS) with a single electrical source is effective for motor symptom relief in patients with Parkinson's disease. We postulated that a multiple-source, constant-current device that permits well defined distribution of current would lead to motor improvement in patients with Parkinson's disease. We did a prospective, multicentre, non-randomised, open-label intervention study of an implantable DBS device (the VANTAGE study) at six specialist DBS centres at universities in six European countries. Patients were judged eligible if they were aged 21-75 years, had been diagnosed with bilateral idiopathic Parkinson's disease with motor symptoms for more than 5 years, had a Hoehn and Yahr score of 2 or greater, and had a Unified Parkinson's disease rating scale part III (UPDRS III) score in the medication-off state of more than 30, which improved by 33% or more after a levodopa challenge. Participants underwent bilateral implantation in the subthalamic nucleus of a multiple-source, constant-current, eight-contact, rechargeable DBS system, and were assessed 12, 26, and 52 weeks after implantation. The primary endpoint was the mean change in UPDRS III scores (assessed by site investigators who were aware of the treatment assignment) from baseline (medication-off state) to 26 weeks after first lead implantation (stimulation-on, medication-off state). This study is registered with ClinicalTrials.gov, number NCT01221948. Of 53 patients enrolled in the study, 40 received a bilateral implant in the subthalamic nucleus and their data contributed to the primary endpoint analysis. Improvement was noted in the UPDRS III motor score 6 months after first lead implantation (mean 13·5 [SD 6·8], 95% CI 11·3-15·7) compared with baseline (37·4 [8·9], 34·5-40·2), with a mean difference of 23·8 (SD 10·6; 95% CI 20·3-27·3; p<0·0001). One patient died of pneumonia 24 weeks after implantation, which was judged to be unrelated to the procedure

  3. Cortical drive of low-frequency oscillations in the human nucleus accumbens during action selection

    PubMed Central

    Litvak, Vladimir; Rutledge, Robb B.; Zaehle, Tino; Schmitt, Friedhelm C.; Voges, Jürgen; Heinze, Hans-Jochen; Dolan, Raymond J.

    2015-01-01

    The nucleus accumbens is thought to contribute to action selection by integrating behaviorally relevant information from multiple regions, including prefrontal cortex. Studies in rodents suggest that information flow to the nucleus accumbens may be regulated via task-dependent oscillatory coupling between regions. During instrumental behavior, local field potentials (LFP) in the rat nucleus accumbens and prefrontal cortex are coupled at delta frequencies (Gruber AJ, Hussain RJ, O'Donnell P. PLoS One 4: e5062, 2009), possibly mediating suppression of afferent input from other areas and thereby supporting cortical control (Calhoon GG, O'Donnell P. Neuron 78: 181–190, 2013). In this report, we demonstrate low-frequency cortico-accumbens coupling in humans, both at rest and during a decision-making task. We recorded LFP from the nucleus accumbens in six epilepsy patients who underwent implantation of deep brain stimulation electrodes. All patients showed significant coherence and phase-synchronization between LFP and surface EEG at delta and low theta frequencies. Although the direction of this coupling as indexed by Granger causality varied between subjects in the resting-state data, all patients showed a cortical drive of the nucleus accumbens during action selection in a decision-making task. In three patients this was accompanied by a significant coherence increase over baseline. Our results suggest that low-frequency cortico-accumbens coupling represents a highly conserved regulatory mechanism for action selection. PMID:25878159

  4. Subthalamic Nucleus Stimulation Modulates Motor Cortex Oscillatory Activity in Parkinson's Disease

    ERIC Educational Resources Information Center

    Devos, D.; Labyt, E.; Derambure, P.; Bourriez, J. L.; Cassim, F.; Reyns, N.; Blond, S.; Guieu, J. D.; Destee, A.; Defebvre, L.

    2004-01-01

    In Parkinson's disease, impaired motor preparation has been related to an increased latency in the appearance of movement-related desynchronization (MRD) throughout the contralateral primary sensorimotor (PSM) cortex. Internal globus pallidus (GPi) stimulation improved movement desynchronization over the PSM cortex during movement execution but…

  5. An excitatory paraventricular nucleus to AgRP neuron circuit that drives hunger.

    PubMed

    Krashes, Michael J; Shah, Bhavik P; Madara, Joseph C; Olson, David P; Strochlic, David E; Garfield, Alastair S; Vong, Linh; Pei, Hongjuan; Watabe-Uchida, Mitsuko; Uchida, Naoshige; Liberles, Stephen D; Lowell, Bradford B

    2014-03-13

    Hunger is a hard-wired motivational state essential for survival. Agouti-related peptide (AgRP)-expressing neurons in the arcuate nucleus (ARC) at the base of the hypothalamus are crucial to the control of hunger. They are activated by caloric deficiency and, when naturally or artificially stimulated, they potently induce intense hunger and subsequent food intake. Consistent with their obligatory role in regulating appetite, genetic ablation or chemogenetic inhibition of AgRP neurons decreases feeding. Excitatory input to AgRP neurons is important in caloric-deficiency-induced activation, and is notable for its remarkable degree of caloric-state-dependent synaptic plasticity. Despite the important role of excitatory input, its source(s) has been unknown. Here, through the use of Cre-recombinase-enabled, cell-specific neuron mapping techniques in mice, we have discovered strong excitatory drive that, unexpectedly, emanates from the hypothalamic paraventricular nucleus, specifically from subsets of neurons expressing thyrotropin-releasing hormone (TRH) and pituitary adenylate cyclase-activating polypeptide (PACAP, also known as ADCYAP1). Chemogenetic stimulation of these afferent neurons in sated mice markedly activates AgRP neurons and induces intense feeding. Conversely, acute inhibition in mice with caloric-deficiency-induced hunger decreases feeding. Discovery of these afferent neurons capable of triggering hunger advances understanding of how this intense motivational state is regulated.

  6. Load-Dependent Interference of Deep Brain Stimulation of the Subthalamic Nucleus with Switching from Automatic to Controlled Processing During Random Number Generation in Parkinson's Disease.

    PubMed

    Williams, Isobel Anne; Wilkinson, Leonora; Limousin, Patricia; Jahanshahi, Marjan

    2015-01-01

    Deep brain stimulation of the subthalamic nucleus (STN DBS) ameliorates the motor symptoms of Parkinson's disease (PD). However, some aspects of executive control are impaired with STN DBS. We tested the prediction that (i) STN DBS interferes with switching from automatic to controlled processing during fast-paced random number generation (RNG) (ii) STN DBS-induced cognitive control changes are load-dependent. Fifteen PD patients with bilateral STN DBS performed paced-RNG, under three levels of cognitive load synchronised with a pacing stimulus presented at 1, 0.5 and 0.33 Hz (faster rates require greater cognitive control), with DBS on or off. Measures of output randomness were calculated. Countscore 1 (CS1) indicates habitual counting in steps of one (CS1). Countscore 2 (CS2) indicates a more controlled strategy of counting in twos. The fastest rate was associated with an increased CS1 score with STN DBS on compared to off. At the slowest rate, patients had higher CS2 scores with DBS off than on, such that the differences between CS1 and CS2 scores disappeared. We provide evidence for a load-dependent effect of STN DBS on paced RNG in PD. Patients could switch to more controlled RNG strategies during conditions of low cognitive load at slower rates only when the STN stimulators were off, but when STN stimulation was on, they engaged in more automatic habitual counting under increased cognitive load. These findings are consistent with the proposal that the STN implements a switch signal from the medial frontal cortex which enables a shift from automatic to controlled processing.

  7. Nucleus Ruber of Actinopterygians.

    PubMed

    Nakayama, Tomoya; Miyajima, Satoshi; Nishino, Hirotaka; Narita, Junya; Abe, Hideki; Yamamoto, Naoyuki

    2016-01-01

    Nucleus ruber is known as an important supraspinal center that controls forelimb movements in tetrapods, and the rubral homologue may serve similar functions in fishes (motor control of pectoral fin). However, two apparently different structures have been identified as 'nucleus ruber' in actinopterygians. One is nucleus ruber of Goldstein (1905) (NRg), and the other nucleus ruber of Nieuwenhuys and Pouwels (1983) (NRnp). It remains unclear whether one of these nuclei (or perhaps both) is homologous to tetrapod nucleus ruber. To resolve this issue from a phylogenetic point of view, we have investigated the distribution of tegmental neurons retrogradely labeled from the spinal cord in eight actinopterygian species. We also investigated the presence/absence of the two nuclei with Nissl- or Bodian-stained brain section series of an additional 28 actinopterygian species by comparing the morphological features of candidate rubral neurons with those of neurons revealed by the tracer studies. Based on these analyses, the NRg was identified in all actinopterygians investigated in the present study, while the NRnp appears to be absent in basal actinopterygians. The phylogenetic distribution pattern indicates that the NRg is the more likely homologue of nucleus ruber, and the NRnp may be a derived nucleus that emerged during the course of actinopterygian evolution. © 2016 S. Karger AG, Basel.

  8. Elastic and viscoelastic mechanical properties of brain tissues on the implanting trajectory of sub-thalamic nucleus stimulation.

    PubMed

    Li, Yan; Deng, Jianxin; Zhou, Jun; Li, Xueen

    2016-11-01

    Corresponding to pre-puncture and post-puncture insertion, elastic and viscoelastic mechanical properties of brain tissues on the implanting trajectory of sub-thalamic nucleus stimulation are investigated, respectively. Elastic mechanical properties in pre-puncture are investigated through pre-puncture needle insertion experiments using whole porcine brains. A linear polynomial and a second order polynomial are fitted to the average insertion force in pre-puncture. The Young's modulus in pre-puncture is calculated from the slope of the two fittings. Viscoelastic mechanical properties of brain tissues in post-puncture insertion are investigated through indentation stress relaxation tests for six interested regions along a planned trajectory. A linear viscoelastic model with a Prony series approximation is fitted to the average load trace of each region using Boltzmann hereditary integral. Shear relaxation moduli of each region are calculated using the parameters of the Prony series approximation. The results show that, in pre-puncture insertion, needle force almost increases linearly with needle displacement. Both fitting lines can perfectly fit the average insertion force. The Young's moduli calculated from the slope of the two fittings are worthy of trust to model linearly or nonlinearly instantaneous elastic responses of brain tissues, respectively. In post-puncture insertion, both region and time significantly affect the viscoelastic behaviors. Six tested regions can be classified into three categories in stiffness. Shear relaxation moduli decay dramatically in short time scales but equilibrium is never truly achieved. The regional and temporal viscoelastic mechanical properties in post-puncture insertion are valuable for guiding probe insertion into each region on the implanting trajectory.

  9. A Computerized Microelectrode Recording to Magnetic Resonance Imaging Mapping System for Subthalamic Nucleus Deep Brain Stimulation Surgery.

    PubMed

    Dodani, Sunjay S; Lu, Charles W; Aldridge, J Wayne; Chou, Kelvin L; Patil, Parag G

    2018-06-01

    Accurate electrode placement is critical to the success of deep brain stimulation (DBS) surgery. Suboptimal targeting may arise from poor initial target localization, frame-based targeting error, or intraoperative brain shift. These uncertainties can make DBS surgery challenging. To develop a computerized system to guide subthalamic nucleus (STN) DBS electrode localization and to estimate the trajectory of intraoperative microelectrode recording (MER) on magnetic resonance (MR) images algorithmically during DBS surgery. Our method is based upon the relationship between the high-frequency band (HFB; 500-2000 Hz) signal from MER and voxel intensity on MR images. The HFB profile along an MER trajectory recorded during surgery is compared to voxel intensity profiles along many potential trajectories in the region of the surgically planned trajectory. From these comparisons of HFB recordings and potential trajectories, an estimate of the MER trajectory is calculated. This calculated trajectory is then compared to actual trajectory, as estimated by postoperative high-resolution computed tomography. We compared 20 planned, calculated, and actual trajectories in 13 patients who underwent STN DBS surgery. Targeting errors for our calculated trajectories (2.33 mm ± 0.2 mm) were significantly less than errors for surgically planned trajectories (2.83 mm ± 0.2 mm; P = .01), improving targeting prediction in 70% of individual cases (14/20). Moreover, in 4 of 4 initial MER trajectories that missed the STN, our method correctly indicated the required direction of targeting adjustment for the DBS lead to intersect the STN. A computer-based algorithm simultaneously utilizing MER and MR information potentially eases electrode localization during STN DBS surgery.

  10. Bilateral subthalamic or pallidal stimulation for Parkinson's disease affects neither memory nor executive functions: a consecutive series of 62 patients.

    PubMed

    Ardouin, C; Pillon, B; Peiffer, E; Bejjani, P; Limousin, P; Damier, P; Arnulf, I; Benabid, A L; Agid, Y; Pollak, P

    1999-08-01

    There is a renewal of interest in surgical approaches including lesions and deep brain stimulation directed at motor subcorticofrontal loops. Bilateral lesioning presents a far greater risk of adverse effects, especially cognitive impairment. Furthermore, the main advantages of the stimulation procedure over lesioning are adaptability and reversibility of effects. The aim of this study was to assess the influence of bilateral stimulation of the subthalamic nucleus or internal globus pallidus on memory and executive functions in Parkinson's disease. Sixty-two patients were assessed before and after 3 to 6 months of chronic bilateral stimulation of the subthalamic nucleus (n = 49) or internal globus pallidus (n = 13). The neuropsychological tests used were the Mattis Dementia Rating Scale, the Grober and Buschke Verbal Learning Test, the Wisconsin Card Sorting Test, category and literal fluency, graphic and motor series, the Stroop Test, and the Trail Making Test. Mood was evaluated by the Beck Depression Inventory. Only 4 of 25 cognitive variables were affected by deep brain stimulation. Under stimulation, performance improved for Parts A and B of the Trail Making Test, but there was a deterioration in literal and total lexical fluency. There was also a mild but significant improvement in mood. It may therefore be concluded that stimulation of the subthalamic nucleus or internal globus pallidus does not change the overall cognitive performance in Parkinson's disease and does not greatly affect the functioning of subcorticofrontal loops involved in cognition in humans. This relative absence of cognitive impairment in bilateral deep brain stimulation is likely because of the accurate positioning of the electrodes, allowing the effects of stimulation to be confined to sensorimotor circuits.

  11. LFP Oscillations in the Mesencephalic Locomotor Region during Voluntary Locomotion

    PubMed Central

    Noga, Brian R.; Sanchez, Francisco J.; Villamil, Luz M.; O’Toole, Christopher; Kasicki, Stefan; Olszewski, Maciej; Cabaj, Anna M.; Majczyński, Henryk; Sławińska, Urszula; Jordan, Larry M.

    2017-01-01

    Oscillatory rhythms in local field potentials (LFPs) are thought to coherently bind cooperating neuronal ensembles to produce behaviors, including locomotion. LFPs recorded from sites that trigger locomotion have been used as a basis for identification of appropriate targets for deep brain stimulation (DBS) to enhance locomotor recovery in patients with gait disorders. Theta band activity (6–12 Hz) is associated with locomotor activity in locomotion-inducing sites in the hypothalamus and in the hippocampus, but the LFPs that occur in the functionally defined mesencephalic locomotor region (MLR) during locomotion have not been determined. Here we record the oscillatory activity during treadmill locomotion in MLR sites effective for inducing locomotion with electrical stimulation in rats. The results show the presence of oscillatory theta rhythms in the LFPs recorded from the most effective MLR stimulus sites (at threshold ≤60 μA). Theta activity increased at the onset of locomotion, and its power was correlated with the speed of locomotion. In animals with higher thresholds (>60 μA), the correlation between locomotor speed and theta LFP oscillations was less robust. Changes in the gamma band (previously recorded in vitro in the pedunculopontine nucleus (PPN), thought to be a part of the MLR) were relatively small. Controlled locomotion was best achieved at 10–20 Hz frequencies of MLR stimulation. Our results indicate that theta and not delta or gamma band oscillation is a suitable biomarker for identifying the functional MLR sites. PMID:28579945

  12. Chronic Deep Brain Stimulation of the Hypothalamic Nucleus in Wistar Rats Alters Circulatory Levels of Corticosterone and Proinflammatory Cytokines

    PubMed Central

    Calleja-Castillo, Juan Manuel; De La Cruz-Aguilera, Dora Luz; Manjarrez, Joaquín; Velasco-Velázquez, Marco Antonio; Morales-Espinoza, Gabriel; Moreno-Aguilar, Julia; Hernández, Maria Eugenia; Aguirre-Cruz, Lucinda

    2013-01-01

    Deep brain stimulation (DBS) is a therapeutic option for several diseases, but its effects on HPA axis activity and systemic inflammation are unknown. This study aimed to detect circulatory variations of corticosterone and cytokines levels in Wistar rats, after 21 days of DBS-at the ventrolateral part of the ventromedial hypothalamic nucleus (VMHvl), unilateral cervical vagotomy (UCVgX), or UCVgX plus DBS. We included the respective control (C) and sham (S) groups (n = 6 rats per group). DBS treated rats had higher levels of TNF-α (120%; P < 0.01) and IFN-γ (305%; P < 0.001) but lower corticosterone concentration (48%; P < 0.001) than C and S. UCVgX animals showed increased corticosterone levels (154%; P < 0.001) versus C and S. UCVgX plus DBS increased IL-1β (402%; P < 0.001), IL-6 (160%; P < 0.001), and corsticosterone (178%; P < 0.001 versus 48%; P < 0.001) compared with the C and S groups. Chronic DBS at VMHvl induced a systemic inflammatory response accompanied by a decrease of HPA axis function. UCVgX rats experienced HPA axis hyperactivity as result of vagus nerve injury; however, DBS was unable to block the HPA axis hyperactivity induced by unilateral cervical vagotomy. Further studies are necessary to explore these findings and their clinical implication. PMID:24235973

  13. Acute and chronic changes in brain activity with deep brain stimulation for refractory depression.

    PubMed

    Conen, Silke; Matthews, Julian C; Patel, Nikunj K; Anton-Rodriguez, José; Talbot, Peter S

    2018-04-01

    Deep brain stimulation is a potential option for patients with treatment-refractory depression. Deep brain stimulation benefits have been reported when targeting either the subgenual cingulate or ventral anterior capsule/nucleus accumbens. However, not all patients respond and optimum stimulation-site is uncertain. We compared deep brain stimulation of the subgenual cingulate and ventral anterior capsule/nucleus accumbens separately and combined in the same seven treatment-refractory depression patients, and investigated regional cerebral blood flow changes associated with acute and chronic deep brain stimulation. Deep brain stimulation-response was defined as reduction in Montgomery-Asberg Depression Rating Scale score from baseline of ≥50%, and remission as a Montgomery-Asberg Depression Rating Scale score ≤8. Changes in regional cerebral blood flow were assessed using [ 15 O]water positron emission tomography. Remitters had higher relative regional cerebral blood flow in the prefrontal cortex at baseline and all subsequent time-points compared to non-remitters and non-responders, with prefrontal cortex regional cerebral blood flow generally increasing with chronic deep brain stimulation. These effects were consistent regardless of stimulation-site. Overall, no significant regional cerebral blood flow changes were apparent when deep brain stimulation was acutely interrupted. Deep brain stimulation improved treatment-refractory depression severity in the majority of patients, with consistent changes in local and distant brain regions regardless of target stimulation. Remission of depression was reached in patients with higher baseline prefrontal regional cerebral blood flow. Because of the small sample size these results are preliminary and further evaluation is necessary to determine whether prefrontal cortex regional cerebral blood flow could be a predictive biomarker of treatment response.

  14. Stimulation of dopamine D4 receptors in the paraventricular nucleus of the hypothalamus of male rats induces hyperphagia: involvement of glutamate.

    PubMed

    Tejas-Juárez, Juan Gabriel; Cruz-Martínez, Ana María; López-Alonso, Verónica Elsa; García-Iglesias, Brenda; Mancilla-Díaz, Juan Manuel; Florán-Garduño, Benjamín; Escartín-Pérez, Rodrigo Erick

    2014-06-22

    Obesity is a serious worldwide health problem, affecting 20-40% of the population in several countries. According to animal models, obesity is related to changes in the expression of proteins that control energy homeostasis and in neurotransmission associated to regulation of food intake. For example, it has been reported that diet-induced obesity produces overexpression of dopamine D4 receptor (D4R) mRNA in the ventromedial hypothalamic nucleus (VMH) of mice. Neurons in the VMH send dense glutamatergic projections to other hypothalamic regions as the paraventricular nucleus (PVN), where multiple signals are integrated to finely regulate energy homeostasis and food intake. Although it is well established that dopaminergic transmission in the hypothalamus plays a key role in modulating feeding, the specific mechanisms involved in the activation of D4R in the PVN and its modulatory action on glutamate release and feeding behavior have remained unexplored. To fill this gap, we characterize the behavioral and neurochemical role of D4R in the PVN. In behavioral experiments, we examined the effects of activation of dopamine D4 receptors in the PVN on food intake and on the behavioral satiety sequence in rats exposed to a food-restricted feeding program. In vitro experiments were conducted to study the effects of activation of dopamine D4 receptors on [(3)H]glutamate release and on plasma corticosterone in explants of the PVN. We found that activation of D4R in the PVN induced inhibition of glutamate release and stimulated food intake by inhibiting satiety. Furthermore, activation of D4R in the PVN decreased plasma levels of corticosterone, and this effect was reverted by NMDA. According to our findings, D4R in the PVN may be a target for the pharmacotherapy for obesity as well as eating disorder patients who show restrictive patterns and overweight. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. Nucleus and nucleus-cytoskeleton connections in 3D cell migration

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liu, Lingling, E-mail: liulingling2012@163.com; Luo, Qing, E-mail: qing.luo@cqu.edu.cn; Sun, Jinghui, E-mail: sunjhemail@163.com

    Cell migration plays an important role in many physiological and pathological settings, ranging from embryonic development to cancer metastasis. Currently, accumulating data suggest that cells migrating in three-dimensional (3D) environments show well-defined differences compared to their well-established two-dimensional (2D) counterparts. During 3D migration, the cell body and nucleus must deform to allow cellular passage through the available spaces, and the deformability of the relatively rigid nucleus may constitute a limiting step. Here, we highlight the key evidence regarding the role of the nuclear mechanics in 3D migration, including the molecular components that govern the stiffness of the nucleus and reviewmore » how the nuclear dynamics are connected to and controlled by cytoskeleton-based migration machinery. Intriguingly, nuclear movement must be coordinated with the cytoskeletal dynamics at the leading and trailing edges, which in turn impact the cytoplasmic dynamics that affect the migration efficiency. Thus, we suggest that alterations in the nuclear structure may facilitate cellular reorganizations that are necessary for efficient migration. - Graphical abstract: Schematic representations of a cell migrating on a 2D substrate and a cell migrating in a 3D extracellular matrix environment. (A) Nucleus-cytoskeleton connections are essential to 3D migration. Mechanical signals are transduced by integrins at the cell surface and channeled to cytoskeletal proteins, which generates prestress. The nucleus-cytoskeleton connections can either act as a stable skeleton to anchor the nuclei or provide active force to move the nuclei. The LINC complex is responsible for the nucleo-cytoskeletal coupling. Nesprins connect the cytoskeletal proteins to the inner nuclear membrane proteins SUN1 and SUN2. The SUN proteins connect to the lamins that form the lamina, which attaches to the chromatin. This physical connectivity transmits the mechanical signals from

  16. Inhibition of spinal reflexes by paramedian reticular nucleus.

    PubMed

    Chai, C Y; Lin, Y F; Wang, H Y; Wu, W C; Yen, C T; Kuo, J S; Wayner, M J

    1990-10-01

    The inhibitory actions of the paramedian reticular nucleus (PRN), and its neighbouring structures, i.e., midline raphe nuclei (MRN) and dorsal medullary depressor area (DMD) on the knee jerk (KnJ) and crossed extension movement (CEM) induced by central sciatic stimulation and on the L5 ventral root response (EVRR) evoked by central tibial stimulation, were studied in cats under urethane (400 mg/kg) and alpha-chloralose (40 mg/kg) anesthesia alone, IP or further paralyzed with atracurium besylate (0.5 mg/kg/30 min), IV. Electrical stimulation of the above areas with rectangular pulses (80 Hz, 1.0 msec, 100-200 microA) decreased systemic arterial blood pressure (SAP) in an average value of: 36 +/- 3 mmHg for PRN; 19 +/- 2 mmHg for MRN; and 23 +/- 3 mmHg for DMD. The KnJ and CEM were almost completely suppressed by simultaneous PRN stimulation. The EVRR, including mono- and polysynaptic spinal reflexes with transmission velocity from 10 to 60 m/sec or above, were also suppressed. MRN stimulation only inhibited the KnJ, CEM and polysynaptic spinal reflexes with transmission velocities between 25 and 60 m/sec, but facilitated spinal reflexes with conduction velocities below 10 m/sec. On the other hand, DMD stimulation resulted in small suppression of KnJ, CEM and inhibition of polysynaptic spinal reflexes with conduction velocities between 25 and 60 m/sec. Even though MRN and DMD partially inhibited polysynaptic spinal reflexes, the magnitude of such inhibition was much smaller than that produced by PRN (-20% and -22% vs. -48%). The above-mentioned PRN effects on SAP and EVRR persisted in chronic animals decerebellated 9-12 days before.(ABSTRACT TRUNCATED AT 250 WORDS)

  17. Bilateral high-frequency stimulation of the subthalamic nucleus on attentional performance: transient deleterious effects and enhanced motivation in both intact and parkinsonian rats

    PubMed Central

    Baunez, Christelle; Christakou, Anastasia; Chudasama, Yogita; Forni, Claude; Robbins, Trevor W.

    2007-01-01

    It is now well established that subthalamic nucleus high-frequency stimulation (STN HFS) alleviates motor problems in Parkinson's disease. However, its efficacy for cognitive function remains a matter of debate. The aim of this study was to assess the effects of STN HFS in rats performing a visual attentional task. Bilateral STN HFS was applied in intact and in bilaterally dopamine (DA)-depleted rats. In all animals, STN HFS had a transient debilitating effect on all the variables measured in the task. In DA-depleted rats, STN HFS did not alleviate the deficits induced by the DA lesion such as omissions and latency to make correct responses, but induced perseverative approaches to the food magazine, an indicator of enhanced motivation. In sham-operated controls, STN HFS significantly reduced accuracy and induced perseverative behaviour, mimicking partially the effects of bilateral STN lesions in the same task. These results are in line with the hypothesis that STN HFS only partially mimics inactivation of STN produced by lesioning and confirm the motivational exacerbation induced by STN inactivation. PMID:17331214

  18. Cognition and Depression Following Deep Brain Stimulation of the Subthalamic Nucleus and Globus Pallidus Pars Internus in Parkinson's Disease: A Meta-Analysis.

    PubMed

    Combs, Hannah L; Folley, Bradley S; Berry, David T R; Segerstrom, Suzanne C; Han, Dong Y; Anderson-Mooney, Amelia J; Walls, Brittany D; van Horne, Craig

    2015-12-01

    Parkinson's disease (PD) is a common, degenerative disorder of the central nervous system. Individuals experience predominantly extrapyramidal symptoms including resting tremor, rigidity, bradykinesia, gait abnormalities, cognitive impairment, depression, and neurobehavioral concerns. Cognitive impairments associated with PD are diverse, including difficulty with attention, processing speed, executive functioning, memory recall, visuospatial functions, word-retrieval, and naming. Deep brain stimulation (DBS) of the subthalamic nucleus (STN) or globus pallidus internus (GPi) is FDA approved and has been shown to be effective in reducing motor symptoms of PD. Studies have found that stimulating STN and GPi are equally effective at improving motor symptoms and dyskinesias; however, there has been discrepancy as to whether the cognitive, behavioral, and mood symptoms are affected differently between the two targets. The present study used random-effects meta-analytic models along with a novel p-curve analytic procedure to compare the potential cognitive and emotional impairments associated with STN-DBS in the current literature to those associated with GPi-DBS. Forty-one articles were reviewed with an aggregated sample size of 1622 patients. Following STN-DBS, small declines were found in psychomotor speed, memory, attention, executive functions, and overall cognition; and moderate declines were found in both semantic and phonemic fluency. However, GPi-DBS resulted in fewer neurocognitive declines than STN-DBS (small declines in attention and small-moderate declines in verbal fluency). With regards to its effect on depression symptomatology, both GPi-DBS and STN-DBS resulted in lower levels of depressive symptoms post-surgery. From a neurocognitive standpoint, both GPi-DBS and STN-DBS produce subtle cognitive declines but appears to be relatively well tolerated.

  19. Emotion recognition impairment and apathy after subthalamic nucleus stimulation in Parkinson's disease have separate neural substrates.

    PubMed

    Drapier, D; Péron, J; Leray, E; Sauleau, P; Biseul, I; Drapier, S; Le Jeune, F; Travers, D; Bourguignon, A; Haegelen, C; Millet, B; Vérin, M

    2008-09-01

    To test the hypothesis that emotion recognition and apathy share the same functional circuit involving the subthalamic nucleus (STN). A consecutive series of 17 patients with advanced Parkinson's disease (PD) was assessed 3 months before (M-3) and 3 months (M+3) after STN deep brain stimulation (DBS). Mean (+/-S.D.) age at surgery was 56.9 (8.7) years. Mean disease duration at surgery was 11.8 (2.6) years. Apathy was measured using the Apathy Evaluation Scale (AES) at both M-3 and M3. Patients were also assessed using a computerised paradigm of facial emotion recognition [Ekman, P., & Friesen, W. V. (1976). Pictures of facial affect. Palo Alto: Consulting Psychologist Press] before and after STN DBS. Prior to this, the Benton Facial Recognition Test was used to check that the ability to perceive faces was intact. Apathy had significantly worsened at M3 (42.5+/-8.9, p=0.006) after STN-DBS, in relation to the preoperative assessment (37.2+/-5.5). There was also a significant reduction in recognition percentages for facial expressions of fear (43.1%+/-22.9 vs. 61.6%+/-21.4, p=0.022) and sadness (52.7%+/-19.1 vs. 67.6%+/-22.8, p=0.031) after STN DBS. However, the postoperative worsening of apathy and emotion recognition impairment were not correlated. Our results confirm that the STN is involved in both the apathy and emotion recognition networks. However, the absence of any correlation between apathy and emotion recognition impairment suggests that the worsening of apathy following surgery could not be explained by a lack of facial emotion recognition and that its behavioural and cognitive components should therefore also be taken into consideration.

  20. The modulatory effect of adaptive deep brain stimulation on beta bursts in Parkinson’s disease

    PubMed Central

    Tinkhauser, Gerd; Pogosyan, Alek; Little, Simon; Beudel, Martijn; Herz, Damian M.; Tan, Huiling

    2017-01-01

    Abstract Adaptive deep brain stimulation uses feedback about the state of neural circuits to control stimulation rather than delivering fixed stimulation all the time, as currently performed. In patients with Parkinson’s disease, elevations in beta activity (13–35 Hz) in the subthalamic nucleus have been demonstrated to correlate with clinical impairment and have provided the basis for feedback control in trials of adaptive deep brain stimulation. These pilot studies have suggested that adaptive deep brain stimulation may potentially be more effective, efficient and selective than conventional deep brain stimulation, implying mechanistic differences between the two approaches. Here we test the hypothesis that such differences arise through differential effects on the temporal dynamics of beta activity. The latter is not constantly increased in Parkinson’s disease, but comes in bursts of different durations and amplitudes. We demonstrate that the amplitude of beta activity in the subthalamic nucleus increases in proportion to burst duration, consistent with progressively increasing synchronization. Effective adaptive deep brain stimulation truncated long beta bursts shifting the distribution of burst duration away from long duration with large amplitude towards short duration, lower amplitude bursts. Critically, bursts with shorter duration are negatively and bursts with longer duration positively correlated with the motor impairment off stimulation. Conventional deep brain stimulation did not change the distribution of burst durations. Although both adaptive and conventional deep brain stimulation suppressed mean beta activity amplitude compared to the unstimulated state, this was achieved by a selective effect on burst duration during adaptive deep brain stimulation, whereas conventional deep brain stimulation globally suppressed beta activity. We posit that the relatively selective effect of adaptive deep brain stimulation provides a rationale for why this

  1. Medial Auditory Thalamus Is Necessary for Acquisition and Retention of Eyeblink Conditioning to Cochlear Nucleus Stimulation

    ERIC Educational Resources Information Center

    Halverson, Hunter E.; Poremba, Amy; Freeman, John H.

    2015-01-01

    Associative learning tasks commonly involve an auditory stimulus, which must be projected through the auditory system to the sites of memory induction for learning to occur. The cochlear nucleus (CN) projection to the pontine nuclei has been posited as the necessary auditory pathway for cerebellar learning, including eyeblink conditioning.…

  2. Fusion cross sections for reactions involving medium and heavy nucleus-nucleus systems

    NASA Astrophysics Data System (ADS)

    Atta, Debasis; Basu, D. N.

    2014-12-01

    Existing data on near-barrier fusion excitation functions of medium and heavy nucleus-nucleus systems have been analyzed by using a simple diffused-barrier formula derived assuming the Gaussian shape of the barrier-height distributions. The fusion cross section is obtained by folding the Gaussian barrier distribution with the classical expression for the fusion cross section for a fixed barrier. The energy dependence of the fusion cross section, thus obtained, provides good description to the existing data on near-barrier fusion and capture excitation functions for medium and heavy nucleus-nucleus systems. The theoretical values for the parameters of the barrier distribution are estimated which can be used for fusion or capture cross-section predictions that are especially important for planning experiments for synthesizing new superheavy elements.

  3. Electromagnetic Nucleus - Nucleus Cross Sections Using Energy Dependent Branching Ratios

    NASA Astrophysics Data System (ADS)

    Adamczyk, Anne; Norbury, John

    2009-11-01

    Energy dependent branching ratios, derived from Weisskopf-Ewing theory, are presented and compared to an energy independent formalism, developed by Norbury, Townsend, and Westfall. The energy dependent branching ratio formalism is more versatile since it allows for not only neutron and proton emission, but also alpha particle, deuteron, helion, and triton emission. A new theoretical method for calculating electromagnetic dissociation (EMD) nucleus - nucleus cross sections, with energy dependent branching ratios, is introduced. Comparisons of photonuclear and nucleus - nucleus cross sections, using energy dependent and independent branching ratios, to experiment are presented. Experimental efforts, by various groups, have focused on measuring cross sections for proton and neutron emission, because proton and neutron emission is generally more probable than heavier particle emission. Consequently, comparisons of energy dependent and independent branching ratios to experiment are made for photoneutron and photoproton cross sections. EMD cross sections for single neutron, proton, and alpha particle removal are calculated and compared to experimental data for a variety of projectile, target, and energy combinations. Results indicate that using energy dependent branching ratios yields better estimates.

  4. The Role of 3T Magnetic Resonance Imaging for Targeting the Human Subthalamic Nucleus in Deep Brain Stimulation for Parkinson Disease.

    PubMed

    Longhi, Michele; Ricciardi, Giuseppe; Tommasi, Giorgio; Nicolato, Antonio; Foroni, Roberto; Bertolasi, Laura; Beltramello, Alberto; Moretto, Giuseppe; Tinazzi, Michele; Gerosa, Massimo

    2015-05-01

    Chronic stimulation of the human subthalamic nucleus (STN) is gradually becoming accepted as a long-term therapeutic option for patients with advanced Parkinson disease (PD). 3Tesla (T) magnetic resonance imaging (MRI) improves contrast resolution in basal ganglia nuclei containing high levels of iron, because of magnetic susceptibility effects that increase significantly as the magnetic field gets higher. This phenomenon can be used for better visualization of the STN and may reduce the time necessary for detailed microrecording (MER) mapping, increasing surgery efficacy and lowering morbidity. The objective of this retrospective study is to analyze a population of 20 deep brain stimulation (DBS) electrode implanted patients with PD divided into two groups in which different targeting methods were used. Mean age was 56 years (range 37 to 69 years). Mean disease duration was 11.6 years. Mean follow-up was 12 months (range 6 to 36 months). Patients were divided into two groups: Group A contained 6 patients who underwent STN targeting using 1T stereotactic (T1w + T2w) MRI plus STN indirect atlas derived targeting. Group B consisted of 14 patients who underwent STN targeting using 3T nonstereotactic (T2w) MRI fused with 1T T1w stereotactic MRI and STN direct targeting. For statistical analysis, we compared (five different parameters in both (matched) groups: Unified Parkinson's disease rating scale (UPDRS) score reduction (medication off before surgery against stimulation on/medication off after surgery), postoperative drug reduction, duration of surgery, the "central preoperative track" chosen as final implantation track during surgery, and correspondence between the targeted STN and the intraoperative neurophysiologic data. Mean UPDRS III score reduction (medication off/stimulation on versus preoperative medication off) was 69% in Group A and 74% in Group B (p = 0.015, log-rank test) respectively. Postoperatively, antiparkinsonian treatment was reduced by 66

  5. Meson-nucleus potentials and the search for meson-nucleus bound states

    NASA Astrophysics Data System (ADS)

    Metag, V.; Nanova, M.; Paryev, E. Ya.

    2017-11-01

    Recent experiments studying the meson-nucleus interaction to extract meson-nucleus potentials are reviewed. The real part of the potentials quantifies whether the interaction is attractive or repulsive while the imaginary part describes the meson absorption in nuclei. The review is focused on mesons which are sufficiently long-lived to potentially form meson-nucleus quasi-bound states. The presentation is confined to meson production off nuclei in photon-, pion-, proton-, and light-ion induced reactions and heavy-ion collisions at energies near the production threshold. Tools to extract the potential parameters are presented. In most cases, the real part of the potential is determined by comparing measured meson momentum distributions or excitation functions with collision model or transport model calculations. The imaginary part is extracted from transparency ratio measurements. Results on K+ ,K0 ,K- , η ,η‧ , ω, and ϕ mesons are presented and compared with theoretical predictions. The interaction of K+ and K0 mesons with nuclei is found to be weakly repulsive, while the K- , η ,η‧ , ω and ϕ meson-nucleus potentials are attractive, however, with widely different strengths. Because of meson absorption in the nuclear medium the imaginary parts of the meson-nucleus potentials are all negative, again with a large spread. An outlook on planned experiments in the charm sector is given. In view of the determined potential parameters, the criteria and chances for experimentally observing meson-nucleus quasi-bound states are discussed. The most promising candidates appear to be the η and η‧ mesons.

  6. Cortical drive of low-frequency oscillations in the human nucleus accumbens during action selection.

    PubMed

    Stenner, Max-Philipp; Litvak, Vladimir; Rutledge, Robb B; Zaehle, Tino; Schmitt, Friedhelm C; Voges, Jürgen; Heinze, Hans-Jochen; Dolan, Raymond J

    2015-07-01

    The nucleus accumbens is thought to contribute to action selection by integrating behaviorally relevant information from multiple regions, including prefrontal cortex. Studies in rodents suggest that information flow to the nucleus accumbens may be regulated via task-dependent oscillatory coupling between regions. During instrumental behavior, local field potentials (LFP) in the rat nucleus accumbens and prefrontal cortex are coupled at delta frequencies (Gruber AJ, Hussain RJ, O'Donnell P. PLoS One 4: e5062, 2009), possibly mediating suppression of afferent input from other areas and thereby supporting cortical control (Calhoon GG, O'Donnell P. Neuron 78: 181-190, 2013). In this report, we demonstrate low-frequency cortico-accumbens coupling in humans, both at rest and during a decision-making task. We recorded LFP from the nucleus accumbens in six epilepsy patients who underwent implantation of deep brain stimulation electrodes. All patients showed significant coherence and phase-synchronization between LFP and surface EEG at delta and low theta frequencies. Although the direction of this coupling as indexed by Granger causality varied between subjects in the resting-state data, all patients showed a cortical drive of the nucleus accumbens during action selection in a decision-making task. In three patients this was accompanied by a significant coherence increase over baseline. Our results suggest that low-frequency cortico-accumbens coupling represents a highly conserved regulatory mechanism for action selection. Copyright © 2015 the American Physiological Society.

  7. Regional influence of cocaine on evoked dopamine release in the nucleus accumbens core: A role for the caudal brainstem.

    PubMed

    Gerth, Ashlynn I; Alhadeff, Amber L; Grill, Harvey J; Roitman, Mitchell F

    2017-01-15

    Cocaine increases dopamine concentration in the nucleus accumbens through competitive binding to the dopamine transporter (DAT). However, it also increases the frequency of dopamine release events, a finding that cannot be explained by action at the DAT alone. Rather, this effect may be mediated by cocaine-induced modulation of brain regions that project to dopamine neurons. To explore regional contributions of cocaine to dopamine signaling, we administered cocaine to the lateral or fourth ventricles and compared the effects on dopamine release in the nucleus accumbens evoked by electrical stimulation of the ventral tegmental area to that of systemically-delivered cocaine. Stimulation trains caused a sharp rise in dopamine followed by a slower return to baseline. The magnitude of dopamine release ([DA]max) as well as the latency to decay to fifty percent of the maximum (t(1/2); index of DAT activity) by each stimulation train were recorded. All routes of cocaine delivery caused an increase in [DA]max; only systemic cocaine caused an increase in t(1/2). Importantly, these data are the first to show that hindbrain (fourth ventricle)-delivered cocaine modulates phasic dopamine signaling. Fourth ventricular cocaine robustly increased cFos immunoreactivity in the nucleus of the solitary tract (NTS), suggesting a neural substrate for hindbrain cocaine-mediated effects on [DA]max. Together, the data demonstrate that cocaine-induced effects on phasic dopamine signaling are mediated via actions throughout the brain including the hindbrain. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  8. Computer program for parameterization of nucleus-nucleus electromagnetic dissociation cross sections

    NASA Technical Reports Server (NTRS)

    Norbury, John W.; Townsend, Lawrence W.; Badavi, Forooz F.

    1988-01-01

    A computer subroutine parameterization of electromagnetic dissociation cross sections for nucleus-nucleus collisions is presented that is suitable for implementation in a heavy ion transport code. The only inputs required are the projectile kinetic energy and the projectile and target charge and mass numbers.

  9. Load-Dependent Interference of Deep Brain Stimulation of the Subthalamic Nucleus with Switching from Automatic to Controlled Processing During Random Number Generation in Parkinson’s Disease

    PubMed Central

    Williams, Isobel Anne; Wilkinson, Leonora; Limousin, Patricia; Jahanshahi, Marjan

    2015-01-01

    Background: Deep brain stimulation of the subthalamic nucleus (STN DBS) ameliorates the motor symptoms of Parkinson’s disease (PD). However, some aspects of executive control are impaired with STN DBS. Objective: We tested the prediction that (i) STN DBS interferes with switching from automatic to controlled processing during fast-paced random number generation (RNG) (ii) STN DBS-induced cognitive control changes are load-dependent. Methods: Fifteen PD patients with bilateral STN DBS performed paced-RNG, under three levels of cognitive load synchronised with a pacing stimulus presented at 1, 0.5 and 0.33 Hz (faster rates require greater cognitive control), with DBS on or off. Measures of output randomness were calculated. Countscore 1 (CS1) indicates habitual counting in steps of one (CS1). Countscore 2 (CS2) indicates a more controlled strategy of counting in twos. Results: The fastest rate was associated with an increased CS1 score with STN DBS on compared to off. At the slowest rate, patients had higher CS2 scores with DBS off than on, such that the differences between CS1 and CS2 scores disappeared. Conclusions: We provide evidence for a load-dependent effect of STN DBS on paced RNG in PD. Patients could switch to more controlled RNG strategies during conditions of low cognitive load at slower rates only when the STN stimulators were off, but when STN stimulation was on, they engaged in more automatic habitual counting under increased cognitive load. These findings are consistent with the proposal that the STN implements a switch signal from the medial frontal cortex which enables a shift from automatic to controlled processing. PMID:25720447

  10. Cornering the fear engram: long-term synaptic changes in the lateral nucleus of the amygdala after fear conditioning.

    PubMed

    Kwon, Jeong-Tae; Choi, June-Seek

    2009-08-05

    Use-dependent synaptic modifications in the lateral nucleus of the amygdala (LA) have been suggested to be the cellular analog of memory trace after pavlovian fear conditioning. However, whether neurophysiological changes in the LA are produced as a direct consequence of associative learning awaits additional proof. Using microstimulation of the medial geniculate nucleus of the thalamus as the conditioned stimulus (CS), we demonstrated that contingent pairings of the brain-stimulation CS and a footshock unconditioned stimulus lead to enhanced synaptic efficacy in the thalamic input to the LA, supporting the hypothesis that localized synaptic alterations underlie fear memory formation.

  11. Nucleus-nucleus interactions between 20 and 65 GeV per nucleon

    NASA Technical Reports Server (NTRS)

    Burnett, T. H.; Derrickson, J. H.; Fountain, W. F.; Meegan, C. A.; Parnell, T. A.; Roberts, F. E.; Watts, J. W.; Oda, H.; Takahashi, Y.; Jones, W. V.

    1987-01-01

    A hybrid electronic-counter/emulsion-chamber instrument was exposed to high-energy cosmic rays on a balloon. The data on 105 nucleus-nucleus collisions in the energy range 20-65 GeV/nucleon and for incident nuclear charges Zp in the range of 22 to 28 are presented. Inclusive characteristics of particle production on different targets (plastic, emulsion, and lead) are shown and compared with models based on the superposition of nucleon-nucleus interactions. Features of a subset of the more central collisions with a plastic target and some characteristics of individual events with the highest multiplicity of produced particles are described.

  12. Subthalamic nucleus phase–amplitude coupling correlates with motor impairment in Parkinson’s disease

    PubMed Central

    van Wijk, Bernadette C.M.; Beudel, Martijn; Jha, Ashwani; Oswal, Ashwini; Foltynie, Tom; Hariz, Marwan I.; Limousin, Patricia; Zrinzo, Ludvic; Aziz, Tipu Z.; Green, Alexander L.; Brown, Peter; Litvak, Vladimir

    2016-01-01

    Objective High-amplitude beta band oscillations within the subthalamic nucleus are frequently associated with Parkinson’s disease but it is unclear how they might lead to motor impairments. Here we investigate a likely pathological coupling between the phase of beta band oscillations and the amplitude of high-frequency oscillations around 300 Hz. Methods We analysed an extensive data set comprising resting-state recordings obtained from deep brain stimulation electrodes in 33 patients before and/or after taking dopaminergic medication. We correlated mean values of spectral power and phase–amplitude coupling with severity of hemibody bradykinesia/rigidity. In addition, we used simultaneously recorded magnetoencephalography to look at functional interactions between the subthalamic nucleus and ipsilateral motor cortex. Results Beta band power and phase–amplitude coupling within the subthalamic nucleus correlated positively with severity of motor impairment. This effect was more pronounced within the low-beta range, whilst coherence between subthalamic nucleus and motor cortex was dominant in the high-beta range. Conclusions We speculate that the beta band might impede pro-kinetic high-frequency activity patterns when phase–amplitude coupling is prominent. Furthermore, results provide evidence for a functional subdivision of the beta band into low and high frequencies. Significance Our findings contribute to the interpretation of oscillatory activity within the cortico-basal ganglia circuit. PMID:26971483

  13. Lack of Intrinsic GABAergic Connections in the Thalamic Reticular Nucleus of the Mouse.

    PubMed

    Hou, Guoqiang; Smith, Alison G; Zhang, Zhong-Wei

    2016-07-06

    It is generally thought that neurons in the thalamic reticular nucleus (TRN) form GABAergic synapses with other TRN neurons and that these interconnections are important for the function of the TRN. However, the existence of such intrinsic connections is controversial. We combine two complementary approaches to examine intrinsic GABAergic connections in the TRN of the mouse. We find that optogenetic stimulation of TRN neurons and their axons evokes GABAergic IPSCs in TRN neurons in mice younger than 2 weeks of age but fails to do so after that age. Blocking synaptic release from TRN neurons through conditional deletion of vesicular GABA transporter has no effect on spontaneous IPSCs recorded in TRN neurons aged 2 weeks or older while dramatically reducing GABAergic transmission in thalamic relay neurons. These results demonstrate that except for a short period after birth, the TRN of the mouse lacks intrinsic GABAergic connections. The thalamic reticular nucleus has a critical role in modulating information transfer from the thalamus to the cortex. It has been proposed that neurons in the thalamic reticular nucleus are interconnected through GABAergic synapses and that these connections serve important functions. Our results show that except for the first 2 weeks after birth, the thalamic reticular nucleus of the mouse lacks intrinsic GABAergic connections. Copyright © 2016 the authors 0270-6474/16/367246-07$15.00/0.

  14. Temporally Coordinated Deep Brain Stimulation in the Dorsal and Ventral Striatum Synergistically Enhances Associative Learning.

    PubMed

    Katnani, Husam A; Patel, Shaun R; Kwon, Churl-Su; Abdel-Aziz, Samer; Gale, John T; Eskandar, Emad N

    2016-01-04

    The primate brain has the remarkable ability of mapping sensory stimuli into motor behaviors that can lead to positive outcomes. We have previously shown that during the reinforcement of visual-motor behavior, activity in the caudate nucleus is correlated with the rate of learning. Moreover, phasic microstimulation in the caudate during the reinforcement period was shown to enhance associative learning, demonstrating the importance of temporal specificity to manipulate learning related changes. Here we present evidence that extends upon our previous finding by demonstrating that temporally coordinated phasic deep brain stimulation across both the nucleus accumbens and caudate can further enhance associative learning. Monkeys performed a visual-motor associative learning task and received stimulation at time points critical to learning related changes. Resulting performance revealed an enhancement in the rate, ceiling, and reaction times of learning. Stimulation of each brain region alone or at different time points did not generate the same effect.

  15. Effect of unilateral versus bilateral electrostimulation in subthalamic nucleus on speech in Parkinsons disease

    NASA Astrophysics Data System (ADS)

    Wang, Emily; Verhagen Metman, Leo; Bakay, Roy; Arzbaecher, Jean; Bernard, Bryan

    2004-05-01

    Previously, it was found that 16 right-handed patients with idiopathic Parkinsons disease who underwent unilateral implantation of deep brain stimulator in subthalamic nucleus (STN) showed significant improvement in their nonspeech motor functions. Eight of the 16 patients had stimulator in the left STN and eight in the right STN. In contrast, their speech function showed very mild improvement that was limited to the respiratory/phonotory subsystems. Further, there seemed a trend that the patients with right STN stimulation did better than those with left STN stimulation. It was speculated that the difference might be due to a micro lesion caused by the surgical procedure to the corticobulbar fibers run in the left internal capsule. This paper reports speech changes associated with bilateral DBS in STN in four of the 16 subjects who elected to have deep brain stimulator implanted in STN on the opposite side of the brain at a later time. Results show negative changes in speech after bilateral DBS in STN. The changes were not limited to the micro lesion effect due to the surgery itself, but also related to the active stimulation on the dominant hemisphere for speech processing. [Work supported by NIH.

  16. Suppression and facilitation of auditory neurons through coordinated acoustic and midbrain stimulation: investigating a deep brain stimulator for tinnitus

    NASA Astrophysics Data System (ADS)

    Offutt, Sarah J.; Ryan, Kellie J.; Konop, Alexander E.; Lim, Hubert H.

    2014-12-01

    Objective. The inferior colliculus (IC) is the primary processing center of auditory information in the midbrain and is one site of tinnitus-related activity. One potential option for suppressing the tinnitus percept is through deep brain stimulation via the auditory midbrain implant (AMI), which is designed for hearing restoration and is already being implanted in deaf patients who also have tinnitus. However, to assess the feasibility of AMI stimulation for tinnitus treatment we first need to characterize the functional connectivity within the IC. Previous studies have suggested modulatory projections from the dorsal cortex of the IC (ICD) to the central nucleus of the IC (ICC), though the functional properties of these projections need to be determined. Approach. In this study, we investigated the effects of electrical stimulation of the ICD on acoustic-driven activity within the ICC in ketamine-anesthetized guinea pigs. Main Results. We observed ICD stimulation induces both suppressive and facilitatory changes across ICC that can occur immediately during stimulation and remain after stimulation. Additionally, ICD stimulation paired with broadband noise stimulation at a specific delay can induce greater suppressive than facilitatory effects, especially when stimulating in more rostral and medial ICD locations. Significance. These findings demonstrate that ICD stimulation can induce specific types of plastic changes in ICC activity, which may be relevant for treating tinnitus. By using the AMI with electrode sites positioned with the ICD and the ICC, the modulatory effects of ICD stimulation can be tested directly in tinnitus patients.

  17. Input/output properties of the lateral vestibular nucleus

    NASA Technical Reports Server (NTRS)

    Boyle, R.; Bush, G.; Ehsanian, R.

    2004-01-01

    This article is a review of work in three species, squirrel monkey, cat, and rat studying the inputs and outputs from the lateral vestibular nucleus (LVN). Different electrophysiological shock paradigms were used to determine the synaptic inputs derived from thick to thin diameter vestibular nerve afferents. Angular and linear mechanical stimulations were used to activate and study the combined and individual contribution of inner ear organs and neck afferents. The spatio-temporal properties of LVN neurons in the decerebrated rat were studied in response to dynamic acceleration inputs using sinusoidal linear translation in the horizontal head plane. Outputs were evaluated using antidromic identification techniques and identified LVN neurons were intracellularly injected with biocytin and their morphology studied.

  18. Theory of feedback controlled brain stimulations for Parkinson's disease

    NASA Astrophysics Data System (ADS)

    Sanzeni, A.; Celani, A.; Tiana, G.; Vergassola, M.

    2016-01-01

    Limb tremor and other debilitating symptoms caused by the neurodegenerative Parkinson's disease are currently treated by administering drugs and by fixed-frequency deep brain stimulation. The latter interferes directly with the brain dynamics by delivering electrical impulses to neurons in the subthalamic nucleus. While deep brain stimulation has shown therapeutic benefits in many instances, its mechanism is still unclear. Since its understanding could lead to improved protocols of stimulation and feedback control, we have studied a mathematical model of the many-body neural network dynamics controlling the dynamics of the basal ganglia. On the basis of the results obtained from the model, we propose a new procedure of active stimulation, that depends on the feedback of the network and that respects the constraints imposed by existing technology. We show by numerical simulations that the new protocol outperforms the standard ones for deep brain stimulation and we suggest future experiments that could further improve the feedback procedure.

  19. Sexual behavior induction of c-Fos in the nucleus accumbens and amphetamine-stimulated locomotor activity are sensitized by previous sexual experience in female Syrian hamsters.

    PubMed

    Bradley, K C; Meisel, R L

    2001-03-15

    Dopamine transmission in the nucleus accumbens can be activated by drugs, stress, or motivated behaviors, and repeated exposure to these stimuli can sensitize this dopamine response. The objectives of this study were to determine whether female sexual behavior activates nucleus accumbens neurons and whether past sexual experience cross-sensitizes neuronal responses in the nucleus accumbens to amphetamine. Using immunocytochemical labeling, c-Fos expression in different subregions (shell vs core at the rostral, middle, and caudal levels) of the nucleus accumbens was examined in female hamsters that had varying amounts of sexual experience. Female hamsters, given either 6 weeks of sexual experience or remaining sexually naive, were tested for sexual behavior by exposure to adult male hamsters. Previous sexual experience increased c-Fos labeling in the rostral and caudal levels but not in the middle levels of the nucleus accumbens. Testing for sexual behavior increased labeling in the core, but not the shell, of the nucleus accumbens. To validate that female sexual behavior can sensitize neurons in the mesolimbic dopamine pathway, the locomotor responses of sexually experienced and sexually naive females to an amphetamine injection were then compared. Amphetamine increased general locomotor activity in all females. However, sexually experienced animals responded sooner to amphetamine than did sexually naive animals. These data indicate that female sexual behavior can activate neurons in the nucleus accumbens and that sexual experience can cross-sensitize neuronal responses to amphetamine. In addition, these results provide additional evidence for functional differences between the shell and core of the nucleus accumbens and across its anteroposterior axis.

  20. Genetic identification of a hindbrain nucleus essential for innate vocalization.

    PubMed

    Hernandez-Miranda, Luis Rodrigo; Ruffault, Pierre-Louis; Bouvier, Julien C; Murray, Andrew J; Morin-Surun, Marie-Pierre; Zampieri, Niccolò; Cholewa-Waclaw, Justyna B; Ey, Elodie; Brunet, Jean-Francois; Champagnat, Jean; Fortin, Gilles; Birchmeier, Carmen

    2017-07-25

    Vocalization in young mice is an innate response to isolation or mechanical stimulation. Neuronal circuits that control vocalization and breathing overlap and rely on motor neurons that innervate laryngeal and expiratory muscles, but the brain center that coordinates these motor neurons has not been identified. Here, we show that the hindbrain nucleus tractus solitarius (NTS) is essential for vocalization in mice. By generating genetically modified newborn mice that specifically lack excitatory NTS neurons, we show that they are both mute and unable to produce the expiratory drive required for vocalization. Furthermore, the muteness of these newborns results in maternal neglect. We also show that neurons of the NTS directly connect to and entrain the activity of spinal (L1) and nucleus ambiguus motor pools located at positions where expiratory and laryngeal motor neurons reside. These motor neurons control expiratory pressure and laryngeal tension, respectively, thereby establishing the essential biomechanical parameters used for vocalization. In summary, our work demonstrates that the NTS is an obligatory component of the neuronal circuitry that transforms breaths into calls.

  1. [Long-term care of Parkinson patients with deep brain stimulation].

    PubMed

    Allert, N; Barbe, M T; Timmermann, L; Coenen, V A

    2011-12-01

    For more than 15 years deep brain stimulation of the subthalamic nucleus and globus pallidus internus have become therapeutic options in advanced Parkinson's disease. The number of patients with long-term treatment is increasing steadily. This review focuses on issues of the long-term care of these Parkinson's patients, including differences of the available deep brain stimulation systems, recommendations for follow-up examinations, implications for medical diagnostics and therapies and an algorithm for symptom deterioration. Today, there is no profound evidence that deep brain stimulation prevents disease progression. However, symptomatic relief from motor symptoms is maintained during long-term follow-up and interruption of the therapy remains an exception. © Georg Thieme Verlag KG Stuttgart · New York.

  2. The modulatory effect of adaptive deep brain stimulation on beta bursts in Parkinson's disease.

    PubMed

    Tinkhauser, Gerd; Pogosyan, Alek; Little, Simon; Beudel, Martijn; Herz, Damian M; Tan, Huiling; Brown, Peter

    2017-04-01

    Adaptive deep brain stimulation uses feedback about the state of neural circuits to control stimulation rather than delivering fixed stimulation all the time, as currently performed. In patients with Parkinson's disease, elevations in beta activity (13-35 Hz) in the subthalamic nucleus have been demonstrated to correlate with clinical impairment and have provided the basis for feedback control in trials of adaptive deep brain stimulation. These pilot studies have suggested that adaptive deep brain stimulation may potentially be more effective, efficient and selective than conventional deep brain stimulation, implying mechanistic differences between the two approaches. Here we test the hypothesis that such differences arise through differential effects on the temporal dynamics of beta activity. The latter is not constantly increased in Parkinson's disease, but comes in bursts of different durations and amplitudes. We demonstrate that the amplitude of beta activity in the subthalamic nucleus increases in proportion to burst duration, consistent with progressively increasing synchronization. Effective adaptive deep brain stimulation truncated long beta bursts shifting the distribution of burst duration away from long duration with large amplitude towards short duration, lower amplitude bursts. Critically, bursts with shorter duration are negatively and bursts with longer duration positively correlated with the motor impairment off stimulation. Conventional deep brain stimulation did not change the distribution of burst durations. Although both adaptive and conventional deep brain stimulation suppressed mean beta activity amplitude compared to the unstimulated state, this was achieved by a selective effect on burst duration during adaptive deep brain stimulation, whereas conventional deep brain stimulation globally suppressed beta activity. We posit that the relatively selective effect of adaptive deep brain stimulation provides a rationale for why this approach could

  3. Subthalamic stimulation improves the cerebral hemodynamic response to the cold pressure test in patients with Parkinson's disease.

    PubMed

    Rätsep, Tõnu; Asser, Toomas

    2012-01-01

    Disturbances of the autonomic nervous system are common in patients with Parkinson's disease (PD) but the effect of deep brain stimulation of the subthalamic nucleus on cerebrovascular reactivity is not entirely known. Seven patients in an advanced stage of the disease and seven healthy age-matched controls participated in the study, which took place after one night of drug withdrawal. Cerebral blood flow velocity was continuously monitored on both sides with transcranial Doppler ultrasound, and cerebrovascular reactivity (CR) was evaluated with the cold pressure test. The measurements were repeated and compared during the stimulation-on and -off phases. The PD patients had significantly higher CR values in the stimulation-on than -off conditions (15.1% ± 6.9 versus 9.4% ± 6.2; p = 0.03). CR values were higher in controls than in patients in the stimulation-off condition (20.4% ± 12.5 versus 9.4% ± 6.2; p = 0.007) without a significant difference with the stimulation-on phase. CR, evaluated by the response to the cold pressure test, is impaired in patients with advanced PD and improved by subthalamic nucleus. Copyright © 2012 Wiley Periodicals, Inc.

  4. Resting state cortical oscillations of patients with Parkinson disease and with and without subthalamic deep brain stimulation: a magnetoencephalography study.

    PubMed

    Cao, Chunyan; Li, Dianyou; Jiang, Tianxiao; Ince, Nuri Firat; Zhan, Shikun; Zhang, Jing; Sha, Zhiyi; Sun, Bomin

    2015-04-01

    In this study, we investigate the modification to cortical oscillations of patients with Parkinson disease (PD) by subthalamic deep brain stimulation (STN-DBS). Spontaneous cortical oscillations of patients with PD were recorded with magnetoencephalography during on and off subthalamic nucleus deep brain stimulation states. Several features such as average frequency, average power, and relative subband power in regions of interest were extracted in the frequency domain, and these features were correlated with Unified Parkinson Disease Rating Scale III evaluation. The same features were also investigated in patients with PD without surgery and healthy controls. Patients with Parkinson disease without surgery compared with healthy controls had a significantly lower average frequency and an increased average power in 1 to 48 Hz range in whole cortex. Higher relative power in theta and simultaneous decrease in beta and gamma over temporal and occipital were also observed in patients with PD. The Unified Parkinson Disease Rating Scale III rigidity score correlated with the average frequency and with the relative power of beta and gamma in frontal areas. During subthalamic nucleus deep brain stimulation, the average frequency increased significantly when stimulation was on compared with off state. In addition, the relative power dropped in delta, whereas it rose in beta over the whole cortex. Through the course of stimulation, the Unified Parkinson Disease Rating Scale III rigidity and tremor scores correlated with the relative power of alpha over left parietal. Subthalamic nucleus deep brain stimulation improves the symptoms of PD by suppressing the synchronization of alpha rhythm in somatomotor region.

  5. Subthalamic nucleus modulates social and anxogenic-like behaviors.

    PubMed

    Reymann, Jean-Michel; Naudet, Florian; Pihan, Morgane; Saïkali, Stephan; Laviolle, Bruno; Bentué-Ferrer, Danièle

    2013-09-01

    In Parkinson's disease, global social maladjustment and anxiety are frequent after subthalamic nucleus (STN) stimulation and are generally considered to be linked with sociofamilial alterations induced by the motor effects of stimulation. We hypothesized that the STN is per se involved in these changes and aimed to explore the role of STN in social and anxogenic-like behaviors using an animal model. Nineteen male Wistar rats with bilateral lesions of the STN were compared with 26 sham-lesioned rats by synchronizing an ethological approach based upon direct observation of social behaviors and a standardized approach, the elevated plus maze (EPM). Comparisons between groups were performed by a Mann-Whitney-Wilcoxon test. Lesioned rats showed impairments in their social (P=0.05) and aggressive behaviors with a diminution of attacking (P=0.04) and chasing (P=0.06). In the EPM, concerning the open arms, the percentage of distance, time, inactive time, and entry were significantly decreased in lesioned rats (P=0.02, P=0.01, P=0.04, and P=0.05). The time spent in non-protected head dips was also diminished in the lesioned rats (P=0.01). These results strongly implicate the STN in social behavior and anxogenic-like behavior. In human, as DBS induces changes in the underlying dynamics of the stimulated brain networks, it could create an abnormal brain state in which anxiety and social behavior are altered. These results highlight another level of complexity of the behavioral changes after stimulation. Copyright © 2013 Elsevier B.V. All rights reserved.

  6. Rapid adenosine release in the nucleus tractus solitarii during defence response in rats: real-time measurement in vivo

    PubMed Central

    Dale, Nicholas; Gourine, Alexander V; Llaudet, Enrique; Bulmer, David; Thomas, Teresa; Spyer, K Michael

    2002-01-01

    We have measured the release of adenosine and inosine from the dorsal surface of the brainstem and from within the nucleus tractus solitarii (NTS) during the defence response evoked by hypothalamic stimulation in the anaesthetised rat. At the surface of the brainstem, only release of inosine was detected on hypothalamic defence area stimulation. This inosine signal was greatly reduced by addition of the ecto-5′-nucleotidase inhibitor α,β-methylene ADP (200 μM), suggesting that the inosine arose from adenosine that was produced in the extracellular space by the prior release of ATP. By placing a microelectrode biosensor into the NTS under stereotaxic control we have recorded release of adenosine within this nucleus. By contrast to the brainstem surface, a fast increase in adenosine, accompanied only by a much smaller change in inosine levels, was seen following stimulation of the hypothalamic defence area. The release of adenosine following hypothalamic stimulation was mainly confined to a narrow region of the NTS some 500 μm in length around the level of the obex. Interestingly the release of adenosine was depletable: when the defence reaction was evoked at short time intervals, much less adenosine was released on the second stimulus. Our novel techniques have given unprecedented real-time measurement and localisation of adenosine release in vivo and demonstrate that adenosine is released at the right time and in sufficient quantities to contribute to the cardiovascular components of the defence reaction. PMID:12356888

  7. Intrinsic functional connectivity of the central nucleus of the amygdala and bed nucleus of the stria terminalis.

    PubMed

    Gorka, Adam X; Torrisi, Salvatore; Shackman, Alexander J; Grillon, Christian; Ernst, Monique

    2018-03-01

    The central nucleus of the amygdala (CeA) and bed nucleus of the stria terminalis (BNST), two nuclei within the central extended amygdala, function as critical relays within the distributed neural networks that coordinate sensory, emotional, and cognitive responses to threat. These structures have overlapping anatomical projections to downstream targets that initiate defensive responses. Despite these commonalities, researchers have also proposed a functional dissociation between the CeA and BNST, with the CeA promoting responses to discrete stimuli and the BNST promoting responses to diffuse threat. Intrinsic functional connectivity (iFC) provides a means to investigate the functional architecture of the brain, unbiased by task demands. Using ultra-high field neuroimaging (7-Tesla fMRI), which provides increased spatial resolution, this study compared the iFC networks of the CeA and BNST in 27 healthy individuals. Both structures were coupled with areas of the medial prefrontal cortex, hippocampus, thalamus, and periaqueductal gray matter. Compared to the BNST, the bilateral CeA was more strongly coupled with the insula and regions that support sensory processing, including thalamus and fusiform gyrus. In contrast, the bilateral BNST was more strongly coupled with regions involved in cognitive and motivational processes, including the dorsal paracingulate gyrus, posterior cingulate cortex, and striatum. Collectively, these findings suggest that responses to sensory stimulation are preferentially coordinated by the CeA and cognitive and motivational responses are preferentially coordinated by the BNST. Published by Elsevier Inc.

  8. The immediate effects of peripheral deafferentation on neurons of the cuneate nucleus in raccoons.

    PubMed

    Northgrave, S A; Rasmusson, D D

    1996-01-01

    Single-unit recordings were obtained from 42 neurons in the cuneate nucleus of 12 anesthetized raccoons. All neurons had receptive fields on the glabrous skin of a forepaw digit. Temporary removal of the dominant excitatory input to a neuron, by injection of lidocaine into the base of the digit, did not result in any expansion of the excitatory receptive field onto adjacent, "off-focus" digits. Similarly, the responses evoked from the off-focus digits by electrical stimulation, which had a longer latency and a higher threshold, were not improved during the lidocaine block. Inhibition was produced in the majority of neurons by high-intensity mechanical stimulation of the off-focus digits, but this was also unchanged when the dominant excitatory input to the neurons was blocked. Since this from of inhibition is not apparent in the somatosensory thalamus before denervation, the spontaneous activity of thalamic neurons must be controlled by inputs other than the cuneate nucleus. These results also indicate that the long-term reorganization seen in the thalamus and cortex is not attributable to a simple unmasking of connections from the adjacent digits within the cuneate nucleus, but may involve strengthening of the connections responsible for longer-latency responses. The only significant change induced in cuneate neurons by temporary denervation was a decrease in the firing rates of 69% of the neurons that had spontaneous activity. Since it is unlikely that any of the large-diameter afferents from touch receptors can account for this finding, mechanically insensitive afferent fibers from the digit may contribute to the spontaneous activity of cuneate neurons, either directly or via a relay in the spinal cord.

  9. Raclopride or high-frequency stimulation of the subthalamic nucleus stops cocaine-induced motor stereotypy and restores related alterations in prefrontal basal ganglia circuits.

    PubMed

    Aliane, Verena; Pérez, Sylvie; Deniau, Jean-Michel; Kemel, Marie-Louise

    2012-11-01

    Motor stereotypy is a key symptom of various neurological or neuropsychiatric disorders. Neuroleptics or the promising treatment using deep brain stimulation stops stereotypies but the mechanisms underlying their actions are unclear. In rat, motor stereotypies are linked to an imbalance between prefrontal and sensorimotor cortico-basal ganglia circuits. Indeed, cortico-nigral transmission was reduced in the prefrontal but not sensorimotor basal ganglia circuits and dopamine and acetylcholine release was altered in the prefrontal but not sensorimotor territory of the dorsal striatum. Furthermore, cholinergic transmission in the prefrontal territory of the dorsal striatum plays a crucial role in the arrest of motor stereotypy. Here we found that, as previously observed for raclopride, high-frequency stimulation of the subthalamic nucleus (HFS STN) rapidly stopped cocaine-induced motor stereotypies in rat. Importantly, raclopride and HFS STN exerted a strong effect on cocaine-induced alterations in prefrontal basal ganglia circuits. Raclopride restored the cholinergic transmission in the prefrontal territory of the dorsal striatum and the cortico-nigral information transmissions in the prefrontal basal ganglia circuits. HFS STN also restored the N-methyl-d-aspartic-acid-evoked release of acetylcholine and dopamine in the prefrontal territory of the dorsal striatum. However, in contrast to raclopride, HFS STN did not restore the cortico-substantia nigra pars reticulata transmissions but exerted strong inhibitory and excitatory effects on neuronal activity in the prefrontal subdivision of the substantia nigra pars reticulata. Thus, both raclopride and HFS STN stop cocaine-induced motor stereotypy, but exert different effects on the related alterations in the prefrontal basal ganglia circuits. © 2012 The Authors. European Journal of Neuroscience © 2012 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.

  10. Baroreflex failure in a patient with central nervous system lesions involving the nucleus tractus solitarii

    NASA Technical Reports Server (NTRS)

    Biaggioni, I.; Whetsell, W. O.; Jobe, J.; Nadeau, J. H.

    1994-01-01

    Animal studies have shown the importance of the nucleus tractus solitarii, a collection of neurons in the brain stem, in the acute regulation of blood pressure. Impulses arising from the carotid and aortic baroreceptors converge in this center, where the first synapse of the baroreflex is located. Stimulation of the nucleus tractus solitarii provides an inhibitory signal to other brain stem structures, particularly the rostral ventrolateral medulla, resulting in a reduction in sympathetic outflow and a decrease in blood pressure. Conversely, experimental lesions of the nucleus tractus solitarii lead to loss of baroreflex control of blood pressure, sympathetic activation, and severe hypertension in animals. In humans, baroreflex failure due to deafferentation of baroreceptors has been previously reported and is characterized by episodes of severe hypertension and tachycardia. We present a patient with an undetermined process of the central nervous system characterized pathologically by ubiquitous infarctions that were particularly prominent in the nucleus tractus solitarii bilaterally but spared the rostral ventrolateral medulla. Absence of a functioning baroreflex was evidenced by the lack of reflex tachycardia to the hypotensive effects of sodium nitroprusside, exaggerated pressor responses to handgrip and cold pressor test, and exaggerated depressor responses to meals and centrally acting alpha 2-agonists. This clinicopathological correlate suggests that the patient's baroreflex failure can be explained by the unique combination of the destruction of sympathetic inhibitory centers (ie, the nucleus tractus solitarii) and preservation of centers that exert a positive modulation on sympathetic tone (ie, the rostral ventrolateral medulla).

  11. Deep brain stimulation of the subthalamic nucleus affects resting EEG and visual evoked potentials in Parkinson's disease.

    PubMed

    Jech, Robert; Růzicka, Evzen; Urgosík, Dusan; Serranová, Tereza; Volfová, Markéta; Nováková, Olga; Roth, Jan; Dusek, Petr; Mecír, Petr

    2006-05-01

    We studied changes of the EEG spectral power induced by deep brain stimulation (DBS) of the subthalamic nucleus (STN) in patients with Parkinson's disease (PD). Also analyzed were changes of visual evoked potentials (VEP) with DBS on and off. Eleven patients with advanced PD treated with bilateral DBS STN were examined after an overnight withdrawal of L-DOPA and 2 h after switching off the neurostimulators. All underwent clinical examination followed by resting EEG and VEP recordings, a procedure repeated after DBS STN was switched on. With DBS switched on, the dominant EEG frequency increased from 9.44+/-1.3 to 9.71+/-1.3 Hz (P<0.01) while its relative spectral power dropped by 11% on average (P<0.05). Switching on the neurostimulators caused a decrease in the N70/P100 amplitude of the VEP (P<0.01), which inversely correlated with the intensity of DBS (black-and-white pattern: P<0.01; color pattern: P<0.05). Despite artifacts generated by neurostimulators, the VEP and resting EEG were suitable for the detection of effects related to DBS STN. The acceleration of dominant frequency in the alpha band may be evidence of DBS STN influence on speeding up of intracortical oscillations. The spectral power decrease, seen mainly in the fronto-central region, might reflect a desynchronization in the premotor and motor circuits, though no movement was executed. Similarly, desynchronization of the cortical activity recorded posteriorly may by responsible for the VEP amplitude decrease implying DBS STN-related influence even on the visual system. Changes in idling EEG activity observed diffusely over scalp together with involvement of the VEP suggest that the effects of DBS STN reach far beyond the motor system influencing the basic mechanisms of rhythmic cortical oscillations.

  12. The intercalatus nucleus of Staderini.

    PubMed

    Cascella, Marco

    2016-01-01

    Rutilio Staderini was one of the leading Italian anatomists of the twentieth century, together with some scientists, such as Giulio Chiarugi, Giovanni Vitali, and others. He was also a member of a new generation of anatomists. They had continued the tradition of the most famous Italian scientists, which started from the Renaissance up until the nineteenth century. Although he carried out important studies of neuroanatomy and comparative anatomy, as well as embryology, his name is rarely remembered by most medical historians. His name is linked to the nucleus he discovered: the Staderini nucleus or intercalated nucleus, a collection of nerve cells in the medulla oblongata located lateral to the hypoglossal nucleus. This article focuses on the biography of the neuroanatomist as well as the nucleus that carries his name and his other research, especially on comparative anatomy and embryology.

  13. Repetitive Transcranial Magnetic Stimulation Activates Specific Regions in Rat Brain

    NASA Astrophysics Data System (ADS)

    Ji, Ru-Rong; Schlaepfer, Thomas E.; Aizenman, Carlos D.; Epstein, Charles M.; Qiu, Dike; Huang, Justin C.; Rupp, Fabio

    1998-12-01

    Repetitive transcranial magnetic stimulation (rTMS) is a noninvasive technique to induce electric currents in the brain. Although rTMS is being evaluated as a possible alternative to electroconvulsive therapy for the treatment of refractory depression, little is known about the pattern of activation induced in the brain by rTMS. We have compared immediate early gene expression in rat brain after rTMS and electroconvulsive stimulation, a well-established animal model for electroconvulsive therapy. Our result shows that rTMS applied in conditions effective in animal models of depression induces different patterns of immediate-early gene expression than does electroconvulsive stimulation. In particular, rTMS evokes strong neural responses in the paraventricular nucleus of the thalamus (PVT) and in other regions involved in the regulation of circadian rhythms. The response in PVT is independent of the orientation of the stimulation probe relative to the head. Part of this response is likely because of direct activation, as repetitive magnetic stimulation also activates PVT neurons in brain slices.

  14. Brain circuits mediating baroreflex bradycardia inhibition in rats: an anatomical and functional link between the cuneiform nucleus and the periaqueductal grey

    PubMed Central

    Netzer, Florence; Bernard, Jean-François; Verberne, Anthony J M; Hamon, Michel; Camus, Françoise; Benoliel, Jean-Jacques; Sévoz-Couche, Caroline

    2011-01-01

    Abstract Defence responses triggered experimentally in rats by stimulation of the dorsomedial nucleus of the hypothalamus (DMH) and the dorsolateral periaqueductal grey matter (PAG) inhibit the cardiac baroreflex response (i.e. bradycardia). It has also been proposed that the midbrain cuneiform nucleus (CnF) is involved in active responses. Our aim was to identify the neurocircuitry involved in defence-induced baroreflex inhibition, with a particular focus on the link between DMH, CnF and dorsolateral PAG. Microinjection of the anterograde tracer Phaseolus vulgaris leucoaggutinin into the CnF revealed a dense projection to the dorsolateral PAG. Moreover, activation of neurons in the CnF induced increased expression of Fos protein in the dorsolateral PAG. Inhibition of neurons of the CnF or dorsolateral PAG prevented the inhibition of baroreflex bradycardia induced by DMH or CnF stimulation, respectively. These results provide a detailed description of the brain circuitry underlying acute baroreflex modulation by neurons of the DMH. Our data have shown for the first time that the CnF plays a key role in defence reaction-associated cardiovascular changes; its stimulation, from the DMH, activates the dorsolateral PAG, which, in turn, inhibits baroreflex bradycardia. PMID:21486808

  15. The effect of deep brain stimulation of the subthalamic nucleus on executive functions: impaired verbal fluency and intact updating, planning and conflict resolution in Parkinson's disease.

    PubMed

    Demeter, Gyula; Valálik, István; Pajkossy, Péter; Szőllősi, Ágnes; Lukács, Ágnes; Kemény, Ferenc; Racsmány, Mihály

    2017-04-24

    Although the improvement of motor symptoms in Parkinson's disease (PD) after deep brain stimulation (DBS) of the subthalamic nucleus (STN) is well documented, there are open questions regarding its impact on cognitive functions. The aim of this study was to assess the effect of bilateral DBS of the STN on executive functions in PD patients using a DBS wait-listed PD control group. Ten PD patients with DBS implantation (DBS group) and ten PD wait-listed patients (Clinical control group) participated in the study. Neuropsychological tasks were used to assess general mental ability and various executive functions. Each task was administered twice to each participant: before and after surgery (with the stimulators on) in the DBS group and with a matched delay between the two task administration points in the control group. There was no significant difference between the DBS and the control groups' performance in tasks measuring the updating of verbal, spatial or visual information (Digit span, Corsi and N-back tasks), planning and shifting (Trail Making B), and conflict resolution (Stroop task). However, the DBS group showed a significant decline on the semantic verbal fluency task after surgery compared to the control group, which is in line with findings of previous studies. Our results provide support for the relative cognitive safety of the STN DBS using a wait-listed PD control group. Differential effects of the STN DBS on frontostriatal networks are discussed. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Effects of morphine, physostigmine and raphe nuclei stimulation on 5-hydroxytryptamine release from the cerebral cortex of the cat.

    PubMed Central

    Aiello-Malmberg, P; Bartolini, A; Bartolini, R; Galli, A

    1979-01-01

    1. The release of 5-hydroxytryptamine (5-HT) from the cerebral cortex and caudate nucleus of brainstem-transected cats and from the cerebral cortex of rats anaesthetized with urethane was determined by radioenzymatic and biological assay. 2. The stimulation of nucleus linearis intermedius of raphe doubles the basal 5-HT release in the caudate nucleus and increases it 3 fold in the cerebral cortex. The effects of the electrical stimulation of the raphe are potentiated by chlorimipramine. 3. Brain 5-HT release is greatly increased by morphine hydrochloride (6 mg/kg i.v.) and by physostigmine (100 microgram/kg i.v.), but not by DL-DOPA (50 mg/kg i.v.). 4. It is suggested that the 5-HT releasing action of physostigmine can contribute to some of its pharmacological effects such as the analgesic effect so far attributed exclusively to its indirect cholinomimetic activity. 5. The 5-HT releasing action of physostigmine seems unrelated to its anticholinesterase activity. PMID:435680

  17. Cortical modulation of the nucleus of the optic tract in the rabbit.

    PubMed

    Pettorossi, V E; Troiani, D

    1983-09-01

    We analyzed in rabbits the relationships between the temporooccipital nystagmogenic cortex (NGC)--the region sited at the border between cortical areas 17, 21, and 22--and the nucleus of the optic tract (NOT). Two experimental approaches were used: (a) eye movement analysis before and after electrolytic lesion of the NOT region provided an indication of the importance of the NOT for the interaction between the ocular nystagmus elicited by natural optokinetic stimulation (OKN) and the nystagmus evoked by electrical stimulation of the nystagmogenic area; (b) NOT direction-selective and velocity-sensitive units were tested with single shock or repetitive electrical stimulation of the nystagmogenic region. Single-shock stimulation evoked single or multiple spikes in 50% of NOT units analyzed and repetitive stimuli induced prolonged facilitation and inhibitory rebounds in 70% of the units tested. Comparison of orthodromic activation latencies of the NOT cells (3.2 and 6.1 ms) after cortical stimulation and of antidromic activation latencies of cortical nystagmogenic units (2.6 ms) after NOT shocks, suggested monosynaptic as well as polysynaptic connections between the temporooccipital cortex and the NOT. The existence of such cortical-NOT linkage indicates that the NOT is intercalated between the cortex and the oculomotor centers and represents the most probable site of interaction of the cortical nystagmus pathway with the optokinetic reflex arc.

  18. Neurons of human nucleus accumbens.

    PubMed

    Sazdanović, Maja; Sazdanović, Predrag; Zivanović-Macuzić, Ivana; Jakovljević, Vladimir; Jeremić, Dejan; Peljto, Amir; Tosevski, Jovo

    2011-08-01

    Nucleus accumbens is a part of the ventral striatum also known as a drug active brain region, especially related with drug addiction. The aim of the study was to investigate the Golgi morphology of the nucleus accumbens neurons. The study was performed on the frontal and sagittal sections of 15 human brains by the Golgi Kopsch method. We classified neurons in the human nucleus accumbens according to their morphology and size into four types: type I--fusiform neurons; type II--fusiform neurons with lateral dendrite, arising from a part of the cell body; type III--pyramidal-like neuron; type IV--multipolar neuron. The medium spiny neurons, which are mostly noted regarding to the drug addictive conditions of the brain, correspond to the type IV--multipolar neurons. Two regions of human nucleus accumbens could be clearly recognized on Nissl and Golgi preparations each containing different predominant neuronal types. Central part of nucleus accumbens, core region, has a low density of impregnated neurons with predominant type III, pyramidal-like neurons, with spines on secondary branches and rare type IV, multipolar neurons. Contrary to the core, peripheral region, shell of nucleus, has a high density of impregnated neurons predominantly contained of type I and type IV--multipolar neurons, which all are rich in spines on secondary and tertiary dendritic branches. Our results indicate great morphological variability of human nucleus accumbens neurons. This requires further investigations and clarifying clinical significance of this important brain region.

  19. The Nucleus Introduced

    PubMed Central

    Pederson, Thoru

    2011-01-01

    Now is an opportune moment to address the confluence of cell biological form and function that is the nucleus. Its arrival is especially timely because the recognition that the nucleus is extremely dynamic has now been solidly established as a paradigm shift over the past two decades, and also because we now see on the horizon numerous ways in which organization itself, including gene location and possibly self-organizing bodies, underlies nuclear functions. PMID:20660024

  20. Adaptive deep brain stimulation in advanced Parkinson disease.

    PubMed

    Little, Simon; Pogosyan, Alex; Neal, Spencer; Zavala, Baltazar; Zrinzo, Ludvic; Hariz, Marwan; Foltynie, Thomas; Limousin, Patricia; Ashkan, Keyoumars; FitzGerald, James; Green, Alexander L; Aziz, Tipu Z; Brown, Peter

    2013-09-01

    Brain-computer interfaces (BCIs) could potentially be used to interact with pathological brain signals to intervene and ameliorate their effects in disease states. Here, we provide proof-of-principle of this approach by using a BCI to interpret pathological brain activity in patients with advanced Parkinson disease (PD) and to use this feedback to control when therapeutic deep brain stimulation (DBS) is delivered. Our goal was to demonstrate that by personalizing and optimizing stimulation in real time, we could improve on both the efficacy and efficiency of conventional continuous DBS. We tested BCI-controlled adaptive DBS (aDBS) of the subthalamic nucleus in 8 PD patients. Feedback was provided by processing of the local field potentials recorded directly from the stimulation electrodes. The results were compared to no stimulation, conventional continuous stimulation (cDBS), and random intermittent stimulation. Both unblinded and blinded clinical assessments of motor effect were performed using the Unified Parkinson's Disease Rating Scale. Motor scores improved by 66% (unblinded) and 50% (blinded) during aDBS, which were 29% (p = 0.03) and 27% (p = 0.005) better than cDBS, respectively. These improvements were achieved with a 56% reduction in stimulation time compared to cDBS, and a corresponding reduction in energy requirements (p < 0.001). aDBS was also more effective than no stimulation and random intermittent stimulation. BCI-controlled DBS is tractable and can be more efficient and efficacious than conventional continuous neuromodulation for PD. Copyright © 2013 American Neurological Association.

  1. Effect of repulsive and attractive three-body forces on nucleus-nucleus elastic scattering

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Furumoto, T.; Sakuragi, Y.; Yamamoto, Y.

    2009-10-15

    The effect of the three-body force (TBF) is studied in nucleus-nucleus elastic scattering on the basis of Brueckner theory for nucleon-nucleon (NN) effective interaction (complex G matrix) in the nuclear matter. A new G matrix called CEG07 proposed recently by the present authors includes the TBF effect and reproduces a realistic saturation curve in the nuclear matter, and it is shown to well reproduce proton-nucleus elastic scattering. The microscopic optical potential for the nucleus-nucleus system is obtained by folding the G matrix with nucleon density distributions in colliding nuclei. We first analyze in detail the {sup 16}O+{sup 16}O elastic scatteringmore » at E/A=70 MeV. The observed cross sections are nicely reproduced up to the most backward scattering angles only when the TBF effect is included. The use of the frozen-density approximation (FDA) is essentially important to properly estimate the effect of the TBF in nucleus-nucleus scattering. Other prescriptions for defining the local density have also been tested, but only the FDA prescription gives a proper description of the experimental cross sections as well as the effect of the TBF. The effects of the three-body attraction and the {omega}-rearrangement term are also analyzed. The CEG07 interaction is compared with CDM3Y6, which is a reliable and successful effective density-dependent NN interaction used in the double-folding model. The CEG07 G matrix is also tested in the elastic scattering of {sup 16}O by the {sup 12}C, {sup 28}Si, and {sup 40}Ca targets at E/A=93.9 MeV, and in the elastic scattering of {sup 12}C by the {sup 12}C target at E/A=135 MeV with great success. The decisive effect of the TBF is clearly seen also in those systems. Finally, we have tested CEG07a, CEG07b, and CEG07c for the {sup 16}O+{sup 16}O system at various energies.« less

  2. Remotely Programmed Deep Brain Stimulation of the Bilateral Subthalamic Nucleus for the Treatment of Primary Parkinson Disease: A Randomized Controlled Trial Investigating the Safety and Efficacy of a Novel Deep Brain Stimulation System.

    PubMed

    Li, Dianyou; Zhang, Chencheng; Gault, Judith; Wang, Wei; Liu, Jianmin; Shao, Ming; Zhao, Yanyan; Zeljic, Kristina; Gao, Guodong; Sun, Bomin

    2017-01-01

    Deep brain stimulation (DBS) is the most commonly performed surgery for the debilitating symptoms of Parkinson disease (PD). However, DBS systems remain largely unaffordable to patients in developing countries, warranting the development of a safe, economically viable, and functionally comparable alternative. To investigate the efficacy and safety of wirelessly programmed DBS of bilateral subthalamic nucleus (STN) in patients with primary PD. Sixty-four patients with primary PD were randomly divided into test and control groups (1:1), where DBS was initiated at either 1 month or 3 months, respectively, after surgery. Safety and efficacy of the treatment were compared between on- and off-medication states 3 months after surgery. Outcome measures included analysis of Unified Parkinson's Disease Rating Scale (UPDRS) scores, duration of "on" periods, and daily equivalent doses of levodopa. All patients were followed up both 6 and 12 months after surgery. Three months after surgery, significant decrease in the UPDRS motor scores were observed for the test group in the off-medication state (25.08 ± 1.00) versus the control group (4.20 ± 1.99). Bilateral wireless programming STN-DBS is safe and effective for patients with primary PD in whom medical management has failed to restore motor function. © 2017 S. Karger AG, Basel.

  3. The Nuclear Option: Evidence Implicating the Cell Nucleus in Mechanotransduction.

    PubMed

    Szczesny, Spencer E; Mauck, Robert L

    2017-02-01

    Biophysical stimuli presented to cells via microenvironmental properties (e.g., alignment and stiffness) or external forces have a significant impact on cell function and behavior. Recently, the cell nucleus has been identified as a mechanosensitive organelle that contributes to the perception and response to mechanical stimuli. However, the specific mechanotransduction mechanisms that mediate these effects have not been clearly established. Here, we offer a comprehensive review of the evidence supporting (and refuting) three hypothetical nuclear mechanotransduction mechanisms: physical reorganization of chromatin, signaling at the nuclear envelope, and altered cytoskeletal structure/tension due to nuclear remodeling. Our goal is to provide a reference detailing the progress that has been made and the areas that still require investigation regarding the role of nuclear mechanotransduction in cell biology. Additionally, we will briefly discuss the role that mathematical models of cell mechanics can play in testing these hypotheses and in elucidating how biophysical stimulation of the nucleus drives changes in cell behavior. While force-induced alterations in signaling pathways involving lamina-associated polypeptides (LAPs) (e.g., emerin and histone deacetylase 3 (HDAC3)) and transcription factors (TFs) located at the nuclear envelope currently appear to be the most clearly supported mechanism of nuclear mechanotransduction, additional work is required to examine this process in detail and to more fully test alternative mechanisms. The combination of sophisticated experimental techniques and advanced mathematical models is necessary to enhance our understanding of the role of the nucleus in the mechanotransduction processes driving numerous critical cell functions.

  4. The Nuclear Option: Evidence Implicating the Cell Nucleus in Mechanotransduction

    PubMed Central

    Szczesny, Spencer E.; Mauck, Robert L.

    2017-01-01

    Biophysical stimuli presented to cells via microenvironmental properties (e.g., alignment and stiffness) or external forces have a significant impact on cell function and behavior. Recently, the cell nucleus has been identified as a mechanosensitive organelle that contributes to the perception and response to mechanical stimuli. However, the specific mechanotransduction mechanisms that mediate these effects have not been clearly established. Here, we offer a comprehensive review of the evidence supporting (and refuting) three hypothetical nuclear mechanotransduction mechanisms: physical reorganization of chromatin, signaling at the nuclear envelope, and altered cytoskeletal structure/tension due to nuclear remodeling. Our goal is to provide a reference detailing the progress that has been made and the areas that still require investigation regarding the role of nuclear mechanotransduction in cell biology. Additionally, we will briefly discuss the role that mathematical models of cell mechanics can play in testing these hypotheses and in elucidating how biophysical stimulation of the nucleus drives changes in cell behavior. While force-induced alterations in signaling pathways involving lamina-associated polypeptides (LAPs) (e.g., emerin and histone deacetylase 3 (HDAC3)) and transcription factors (TFs) located at the nuclear envelope currently appear to be the most clearly supported mechanism of nuclear mechanotransduction, additional work is required to examine this process in detail and to more fully test alternative mechanisms. The combination of sophisticated experimental techniques and advanced mathematical models is necessary to enhance our understanding of the role of the nucleus in the mechanotransduction processes driving numerous critical cell functions. PMID:27918797

  5. Single nucleon emission in relativistic nucleus-nucleus reactions

    NASA Technical Reports Server (NTRS)

    Norbury, John W.; Townsend, Lawrence W.

    1992-01-01

    Significant discrepancies between theory and experiment have previously been noted for nucleon emission via electromagnetic processes in relativistic nucleus-nucleus collisions. The present work investigates the hypothesis that these discrepancies have arisen due to uncertainties about how to deduce the experimental electromagnetic cross section from the total measured cross section. An optical-model calculation of single neutron removal is added to electromagnetic cross sections and compared to the total experimental cross sections. Good agreement is found thereby resolving some of the earlier noted discrepancies. A detailed comparison to the recent work of Benesh, Cook, and Vary is made for both the impact parameter and the nuclear cross section. Good agreement is obtained giving an independent confirmation of the parameterized formulas developed by those authors.

  6. Deep brain stimulation reveals emotional impact processing in ventromedial prefrontal cortex.

    PubMed

    Gjedde, Albert; Geday, Jacob

    2009-12-07

    We tested the hypothesis that modulation of monoaminergic tone with deep-brain stimulation (DBS) of subthalamic nucleus would reveal a site of reactivity in the ventromedial prefrontal cortex that we previously identified by modulating serotonergic and noradrenergic mechanisms by blocking serotonin-noradrenaline reuptake sites. We tested the hypothesis in patients with Parkinson's disease in whom we had measured the changes of blood flow everywhere in the brain associated with the deep brain stimulation of the subthalamic nucleus. We determined the emotional reactivity of the patients as the average impact of emotive images rated by the patients off the DBS. We then searched for sites in the brain that had significant correlation of the changes of blood flow with the emotional impact rated by the patients. The results indicate a significant link between the emotional impact when patients are not stimulated and the change of blood flow associated with the DBS. In subjects with a low emotional impact, activity measured as blood flow rose when the electrode was turned on, while in subjects of high impact, the activity at this site in the ventromedial prefrontal cortex declined when the electrode was turned on. We conclude that changes of neurotransmission in the ventromedial prefrontal cortex had an effect on the tissue that depends on changes of monoamine concentration interacting with specific combinations of inhibitory and excitatory monoamine receptors.

  7. Chronic changes in pituitary adenylate cyclase-activating polypeptide and related receptors in response to repeated chemical dural stimulation in rats.

    PubMed

    Han, Xun; Ran, Ye; Su, Min; Liu, Yinglu; Tang, Wenjing; Dong, Zhao; Yu, Shengyuan

    2017-01-01

    Background Preclinical experimental studies revealed an acute alteration of pituitary adenylate cyclase-activating polypeptide in response to a single activation of the trigeminovascular system, which suggests a potential role of pituitary adenylate cyclase-activating polypeptide in the pathogenesis of migraine. However, changes in pituitary adenylate cyclase-activating polypeptide after repeated migraine-like attacks in chronic migraine are not clear. Therefore, the present study investigated chronic changes in pituitary adenylate cyclase-activating polypeptide and related receptors in response to repeated chemical dural stimulations in the rat. Methods A rat model of chronic migraine was established by repeated chemical dural stimulations using an inflammatory soup for a different numbers of days. The pituitary adenylate cyclase-activating polypeptide levels were quantified in plasma, the trigeminal ganglia, and the trigeminal nucleus caudalis using radioimmunoassay and Western blotting in trigeminal ganglia and trigeminal nucleus caudalis tissues. Western blot analysis and real-time polymerase chain reaction were used to measure the protein and mRNA expression of pituitary adenylate cyclase-activating polypeptide-related receptors (PAC1, VPAC1, and VPAC2) in the trigeminal ganglia and trigeminal nucleus caudalis to identify changes associated with repetitive applications of chemical dural stimulations. Results All rats exhibited significantly decreased periorbital nociceptive thresholds to repeated inflammatory soup stimulations. Radioimmunoassay and Western blot analysis demonstrated significantly decreased pituitary adenylate cyclase-activating polypeptide levels in plasma and trigeminal ganglia after repetitive chronic inflammatory soup stimulation. Protein and mRNA analyses of pituitary adenylate cyclase-activating polypeptide-related receptors demonstrated significantly increased PAC1 receptor protein and mRNA expression in the trigeminal ganglia, but not

  8. PRESYNAPTIC DOPAMINE MODULATION BY STIMULANT SELF ADMINISTRATION

    PubMed Central

    España, Rodrigo A.; Jones, Sara R.

    2013-01-01

    The mesolimbic dopamine system is an essential participant in the initiation and modulation of various forms of goal-directed behavior, including drug reinforcement and addiction processes. Dopamine neurotransmission is increased by acute administration of all drugs of abuse, including the stimulants cocaine and amphetamine. Chronic exposure to these drugs via voluntary self-administration provides a model of stimulant abuse that is useful in evaluating potential behavioral and neurochemical adaptations that occur during addiction. This review describes commonly used methodologies to measure dopamine and baseline parameters of presynaptic dopamine regulation, including exocytotic release and reuptake through the dopamine transporter in the nucleus accumbens core, as well as dramatic adaptations in dopamine neurotransmission and drug sensitivity that occur with acute non-contingent and chronic, contingent self-administration of cocaine and amphetamine. PMID:23277050

  9. Hadron-nucleus interactions at high energies

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chiu, C.B.; He, Z.; Tow, D.M.

    1982-06-01

    A simple space-time description of high-energy hadron-nucleus interactions is presented. The model is based on the DTU (dual topologial unitarization)-parton-model description of soft multiparticle production in hadron-hadron interactions. The essentially parameter-free model agrees well with the general features of high-energy data for hadron-nucleus interactions; in particular, this DTU-parton model has a natural explanation for an approximate nu-bar universality. The expansion to high-energy nucleus-nucleus interactions is presented. We also compare and contrast this model with several previously proposed models.

  10. Hadron-nucleus interactions at high energies

    NASA Astrophysics Data System (ADS)

    Chiu, Charles B.; He, Zuoxiu; Tow, Don M.

    1982-06-01

    A simple space-time description of high-energy hadron-nucleus interactions is presented. The model is based on the DTU (dual topological unitarization) -parton-model description of soft multiparticle production in hadron-hadron interactions. The essentially parameter-free model agrees well with the general features of high-energy data for hadron-nucleus interactions; in particular, this DTU-parton model has a natural explanation for an approximate ν¯ universality. The extension to high-energy nucleus-nucleus interactions is presented. We also compare and contrast this model with several previously proposed models.

  11. The pathways connecting the hippocampal formation, the thalamic reuniens nucleus and the thalamic reticular nucleus in the rat.

    PubMed

    Cavdar, Safiye; Onat, Filiz Y; Cakmak, Yusuf Ozgür; Yananli, Hasan R; Gülçebi, Medine; Aker, Rezzan

    2008-03-01

    Most dorsal thalamic nuclei send axons to specific areas of the neocortex and to specific sectors of the thalamic reticular nucleus; the neocortex then sends reciprocal connections back to the same thalamic nucleus, directly as well indirectly through a relay in the thalamic reticular nucleus. This can be regarded as a 'canonical' circuit of the sensory thalamus. For the pathways that link the thalamus and the hippocampal formation, only a few comparable connections have been described. The reuniens nucleus of the thalamus sends some of its major cortical efferents to the hippocampal formation. The present study shows that cells of the hippocampal formation as well as cells in the reuniens nucleus are retrogradely labelled following injections of horseradish peroxidase or fluoro-gold into the rostral part of the thalamic reticular nucleus in the rat. Within the hippocampal formation, labelled neurons were localized in the subiculum, predominantly on the ipsilateral side, with fewer neurons labelled contralaterally. Labelled neurons were seen in the hippocampal formation and nucleus reuniens only after injections made in the rostral thalamic reticular nucleus (1.6-1.8 mm caudal to bregma). In addition, the present study confirmed the presence of afferent connections to the rostral thalamic reticular nucleus from cortical (cingulate, orbital and infralimbic, retrosplenial and frontal), midline thalamic (paraventricular, anteromedial, centromedial and mediodorsal thalamic nuclei) and brainstem structures (substantia nigra pars reticularis, ventral tegmental area, periaqueductal grey, superior vestibular and pontine reticular nuclei). These results demonstrate a potential for the thalamo-hippocampal circuitry to influence the functional roles of the thalamic reticular nucleus, and show that thalamo-hippocampal connections resemble the circuitry that links the sensory thalamus and neocortex.

  12. The pathways connecting the hippocampal formation, the thalamic reuniens nucleus and the thalamic reticular nucleus in the rat

    PubMed Central

    Çavdar, Safiye; Onat, Filiz Y; Çakmak, Yusuf Özgür; Yananli, Hasan R; Gülçebi, Medine; Aker, Rezzan

    2008-01-01

    Most dorsal thalamic nuclei send axons to specific areas of the neocortex and to specific sectors of the thalamic reticular nucleus; the neocortex then sends reciprocal connections back to the same thalamic nucleus, directly as well indirectly through a relay in the thalamic reticular nucleus. This can be regarded as a ‘canonical’ circuit of the sensory thalamus. For the pathways that link the thalamus and the hippocampal formation, only a few comparable connections have been described. The reuniens nucleus of the thalamus sends some of its major cortical efferents to the hippocampal formation. The present study shows that cells of the hippocampal formation as well as cells in the reuniens nucleus are retrogradely labelled following injections of horseradish peroxidase or fluoro-gold into the rostral part of the thalamic reticular nucleus in the rat. Within the hippocampal formation, labelled neurons were localized in the subiculum, predominantly on the ipsilateral side, with fewer neurons labelled contralaterally. Labelled neurons were seen in the hippocampal formation and nucleus reuniens only after injections made in the rostral thalamic reticular nucleus (1.6–1.8 mm caudal to bregma). In addition, the present study confirmed the presence of afferent connections to the rostral thalamic reticular nucleus from cortical (cingulate, orbital and infralimbic, retrosplenial and frontal), midline thalamic (paraventricular, anteromedial, centromedial and mediodorsal thalamic nuclei) and brainstem structures (substantia nigra pars reticularis, ventral tegmental area, periaqueductal grey, superior vestibular and pontine reticular nuclei). These results demonstrate a potential for the thalamo-hippocampal circuitry to influence the functional roles of the thalamic reticular nucleus, and show that thalamo-hippocampal connections resemble the circuitry that links the sensory thalamus and neocortex. PMID:18221482

  13. CRTC2 activation in the suprachiasmatic nucleus, but not paraventricular nucleus, varies in a diurnal fashion and increases with nighttime light exposure.

    PubMed

    Highland, Julie A; Weiser, Michael J; Hinds, Laura R; Spencer, Robert L

    2014-10-01

    Entrainment of the intrinsic suprachiasmatic nucleus (SCN) molecular clock to the light-dark cycle depends on photic-driven intracellular signal transduction responses of SCN neurons that converge on cAMP response element-binding protein (CREB)-mediated regulation of gene transcription. Characterization of the CREB coactivator proteins CREB-regulated transcriptional coactivators (CRTCs) has revealed a greater degree of differential activity-dependent modulation of CREB transactivational function than previously appreciated. In confirmation of recent reports, we found an enrichment of crtc2 mRNA and prominent CRTC2 protein expression within the SCN of adult male rats. With use of a hypothalamic organotypic culture preparation for initial CRTC2-reactive antibody characterization, we found that CRTC2 immunoreactivity in hypothalamic neurons shifted from a predominantly cytoplasmic profile under basal culture conditions to a primarily nuclear localization (CRTC2 activation) 30 min after adenylate cyclase stimulation. In adult rat SCN, we found a diurnal variation in CRTC2 activation (peak at zeitgeber time of 4 h and trough at zeitgeber time of 16-20 h) but no variation in the total number of CRTC2-immunoreactive cells. There was no diurnal variation of CRTC2 activation in the hypothalamic paraventricular nucleus, another site of enriched CRTC2 expression. Exposure of rats to light (50 lux) for 30 min during the second half of their dark (nighttime) phase produced CRTC2 activation. We observed in the SCN a parallel change in the expression of a CREB-regulated gene (FOS). In contrast, nighttime light exposure had no effect on CRTC2 activation or FOS expression in the paraventricular nucleus, nor did it affect corticosterone hormone levels. These results suggest that CRTC2 participates in CREB-dependent photic entrainment of SCN function. Copyright © 2014 the American Physiological Society.

  14. Capsaicin-responsive corneal afferents do not contain TRPV1 at their central terminals in trigeminal nucleus caudalis in rats.

    PubMed

    Hegarty, Deborah M; Hermes, Sam M; Largent-Milnes, Tally M; Aicher, Sue A

    2014-11-01

    We examined the substrates for ocular nociception in adult male Sprague-Dawley rats. Capsaicin application to the ocular surface in awake rats evoked nocifensive responses and suppressed spontaneous grooming responses. Thus, peripheral capsaicin was able to activate the central pathways encoding ocular nociception. Our capsaicin stimulus evoked c-Fos expression in a select population of neurons within rostral trigeminal nucleus caudalis in anesthetized rats. These activated neurons also received direct contacts from corneal afferent fibers traced with cholera toxin B from the corneal surface. However, the central terminals of the corneal afferents that contacted capsaicin-activated trigeminal neurons did not contain TRPV1. To determine if TRPV1 expression had been altered by capsaicin stimulation, we examined TRPV1 content of corneal afferents in animals that did not receive capsaicin stimulation. These studies confirmed that while TRPV1 was present in 30% of CTb-labeled corneal afferent neurons within the trigeminal ganglion, TRPV1 was only detected in 2% of the central terminals of these corneal afferents within the trigeminal nucleus caudalis. Other TRP channels were also present in low proportions of central corneal afferent terminals in unstimulated animals (TRPM8, 2%; TRPA1, 10%). These findings indicate that a pathway from the cornea to rostral trigeminal nucleus caudalis is involved in corneal nociceptive transmission, but that central TRP channel expression is unrelated to the type of stimulus transduced by the peripheral nociceptive endings. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. A circuit for detection of interaural time differences in the nucleus laminaris of turtles.

    PubMed

    Willis, Katie L; Carr, Catherine E

    2017-11-15

    The physiological hearing range of turtles is approximately 50-1000 Hz, as determined by cochlear microphonics ( Wever and Vernon, 1956a). These low frequencies can constrain sound localization, particularly in red-eared slider turtles, which are freshwater turtles with small heads and isolated middle ears. To determine if these turtles were sensitive to interaural time differences (ITDs), we investigated the connections and physiology of their auditory brainstem nuclei. Tract tracing experiments showed that cranial nerve VIII bifurcated to terminate in the first-order nucleus magnocellularis (NM) and nucleus angularis (NA), and the NM projected bilaterally to the nucleus laminaris (NL). As the NL received inputs from each side, we developed an isolated head preparation to examine responses to binaural auditory stimulation. Magnocellularis and laminaris units responded to frequencies from 100 to 600 Hz, and phase-locked reliably to the auditory stimulus. Responses from the NL were binaural, and sensitive to ITD. Measures of characteristic delay revealed best ITDs around ±200 μs, and NL neurons typically had characteristic phases close to 0, consistent with binaural excitation. Thus, turtles encode ITDs within their physiological range, and their auditory brainstem nuclei have similar connections and cell types to other reptiles. © 2017. Published by The Company of Biologists Ltd.

  16. Pairing tone trains with vagus nerve stimulation induces temporal plasticity in auditory cortex.

    PubMed

    Shetake, Jai A; Engineer, Navzer D; Vrana, Will A; Wolf, Jordan T; Kilgard, Michael P

    2012-01-01

    The selectivity of neurons in sensory cortex can be modified by pairing neuromodulator release with sensory stimulation. Repeated pairing of electrical stimulation of the cholinergic nucleus basalis, for example, induces input specific plasticity in primary auditory cortex (A1). Pairing nucleus basalis stimulation (NBS) with a tone increases the number of A1 neurons that respond to the paired tone frequency. Pairing NBS with fast or slow tone trains can respectively increase or decrease the ability of A1 neurons to respond to rapidly presented tones. Pairing vagus nerve stimulation (VNS) with a single tone alters spectral tuning in the same way as NBS-tone pairing without the need for brain surgery. In this study, we tested whether pairing VNS with tone trains can change the temporal response properties of A1 neurons. In naïve rats, A1 neurons respond strongly to tones repeated at rates up to 10 pulses per second (pps). Repeatedly pairing VNS with 15 pps tone trains increased the temporal following capacity of A1 neurons and repeatedly pairing VNS with 5 pps tone trains decreased the temporal following capacity of A1 neurons. Pairing VNS with tone trains did not alter the frequency selectivity or tonotopic organization of auditory cortex neurons. Since VNS is well tolerated by patients, VNS-tone train pairing represents a viable method to direct temporal plasticity in a variety of human conditions associated with temporal processing deficits. Copyright © 2011 Elsevier Inc. All rights reserved.

  17. Serotonin projection patterns to the cochlear nucleus.

    PubMed

    Thompson, A M; Thompson, G C

    2001-07-13

    The cochlear nucleus is well known as an obligatory relay center for primary auditory nerve fibers. Perhaps not so well known is the neural input to the cochlear nucleus from cells containing serotonin that reside near the midline in the midbrain raphe region. Although the specific locations of the main, if not sole, sources of serotonin within the dorsal cochlear nucleus subdivision are known to be the dorsal and median raphe nuclei, sources of serotonin located within other cochlear nucleus subdivisions are not currently known. Anterograde tract tracing was used to label fibers originating from the dorsal and median raphe nuclei while fluorescence immunohistochemistry was used to simultaneously label specific serotonin fibers in cat. Biotinylated dextran amine was injected into the dorsal and median raphe nuclei and was visualized with Texas Red, while serotonin was visualized with fluorescein. Thus, double-labeled fibers were unequivocally identified as serotoninergic and originating from one of the labeled neurons within the dorsal and median raphe nuclei. Double-labeled fiber segments, typically of fine caliber with oval varicosities, were observed in many areas of the cochlear nucleus. They were found in the molecular layer of the dorsal cochlear nucleus, in the small cell cap region, and in the granule cell and external regions of the cochlear nuclei, bilaterally, of all cats. However, the density of these double-labeled fiber segments varied considerably depending upon the exact region in which they were found. Fiber segments were most dense in the dorsal cochlear nucleus (especially in the molecular layer) and the large spherical cell area of the anteroventral cochlear nucleus; they were moderately dense in the small cell cap region; and fiber segments were least dense in the octopus and multipolar cell regions of the posteroventral cochlear nucleus. Because of the presence of labeled fiber segments in subdivisions of the cochlear nucleus other than the

  18. Actomyosin contractility rotates the cell nucleus.

    PubMed

    Kumar, Abhishek; Maitra, Ananyo; Sumit, Madhuresh; Ramaswamy, Sriram; Shivashankar, G V

    2014-01-21

    The cell nucleus functions amidst active cytoskeletal filaments, but its response to their contractile stresses is largely unexplored. We study the dynamics of the nuclei of single fibroblasts, with cell migration suppressed by plating onto micro-fabricated patterns. We find the nucleus undergoes noisy but coherent rotational motion. We account for this observation through a hydrodynamic approach, treating the nucleus as a highly viscous inclusion residing in a less viscous fluid of orientable filaments endowed with active stresses. Lowering actin contractility selectively by introducing blebbistatin at low concentrations drastically reduced the speed and coherence of the angular motion of the nucleus. Time-lapse imaging of actin revealed a correlated hydrodynamic flow around the nucleus, with profile and magnitude consistent with the results of our theoretical approach. Coherent intracellular flows and consequent nuclear rotation thus appear to be an intrinsic property of cells.

  19. Results on ultra-relativistic nucleus-nucleus interactions from balloon-borne emulsion chambers

    NASA Technical Reports Server (NTRS)

    Burnett, T. H.; Dake, S.; Derrickson, J. H.; Fountain, W.; Meegan, C. A.; Takahashi, Y.; Watts, J. W.; Fuki, M.; Gregory, J. C.; Hayashi, T.

    1985-01-01

    The results of balloon-borne emulsion-chamber measurements on high-energy cosmic-ray nuclei (Burnett et al., 1983) are summarized in tables and graphs and briefly characterized. Special consideration is given to seven nucleus-nucleus interaction events at energy in excess of 1 TeV/A with multiplicity greater than 400, and to Fe interactions (53 with CHO, 10 with emulsion, and 14 with Pb) at 20-60 GeV/A.

  20. Microelectrode Recordings Validate the Clinical Visualization of Subthalamic-Nucleus Based on 7T Magnetic Resonance Imaging and Machine Learning for Deep Brain Stimulation Surgery.

    PubMed

    Shamir, Reuben R; Duchin, Yuval; Kim, Jinyoung; Patriat, Remi; Marmor, Odeya; Bergman, Hagai; Vitek, Jerrold L; Sapiro, Guillermo; Bick, Atira; Eliahou, Ruth; Eitan, Renana; Israel, Zvi; Harel, Noam

    2018-05-24

    Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is a proven and effective therapy for the management of the motor symptoms of Parkinson's disease (PD). While accurate positioning of the stimulating electrode is critical for success of this therapy, precise identification of the STN based on imaging can be challenging. We developed a method to accurately visualize the STN on a standard clinical magnetic resonance imaging (MRI). The method incorporates a database of 7-Tesla (T) MRIs of PD patients together with machine-learning methods (hereafter 7 T-ML). To validate the clinical application accuracy of the 7 T-ML method by comparing it with identification of the STN based on intraoperative microelectrode recordings. Sixteen PD patients who underwent microelectrode-recordings guided STN DBS were included in this study (30 implanted leads and electrode trajectories). The length of the STN along the electrode trajectory and the position of its contacts to dorsal, inside, or ventral to the STN were compared using microelectrode-recordings and the 7 T-ML method computed based on the patient's clinical 3T MRI. All 30 electrode trajectories that intersected the STN based on microelectrode-recordings, also intersected it when visualized with the 7 T-ML method. STN trajectory average length was 6.2 ± 0.7 mm based on microelectrode recordings and 5.8 ± 0.9 mm for the 7 T-ML method. We observed a 93% agreement regarding contact location between the microelectrode-recordings and the 7 T-ML method. The 7 T-ML method is highly consistent with microelectrode-recordings data. This method provides a reliable and accurate patient-specific prediction for targeting the STN.

  1. Neuropsychological and quality of life assessment in patients with Parkinson's disease submitted to bilateral deep brain stimulation in the subthalamic nucleus

    PubMed Central

    Heluani, Alessandra Shenandoa; Porto, Fábio Henrique de Gobbi; Listik, Sergio; de Campos, Alexandre Walter; Machado, Alexandre Aluizio Costa; Cukiert, Arthur; de Oliveira Jr, José Oswaldo

    2012-01-01

    Deep brain stimulation (DBS) has been widely used to control motor symptoms and improve quality of life in patients with Parkinsons disease (PD). Recently, DBS in the subthalamic nucleus (STN) has become the preferred target for patients with mixed motor symptoms. Despite resultant motor and quality of life improvements, the procedure has been associated with cognitive decline, mainly in language skills, and also with psychiatric symptoms. Objective To evaluate the influence of DBS in the STN on cognition, mood and quality of life. Methods We studied 20 patients with PD submitted to DBS in the STN from May 2008 to June 2012 with an extensive battery of cognitive tests including memory, language, praxis, executive functions and attention assessments; the Parkinson's Disease Quality of Life Questionnaire (PDQ-39); and the Hospital Anxiety and Depression Scale (HAD), were applied both before and after the surgery. Data was analyzed using SPSS version 17.0 and results compared using the paired Student's t test. Results A total of 20 patients with pre and post-operative assessments were included. A statistically significant improvement was found in total score and on subscales of mobility, activities of daily living and emotional well-being from the PDQ-39 (P=0.009, 0.025, 0.001 and 0.034, respectively). No significant difference was found on the cognitive battery or mood scale. Conclusion DBS in the SNT improved quality of life in PD with no negative impact on cognitive skills and mood. PMID:29213806

  2. Virtual photon polarization and dilepton anisotropy in relativistic nucleus-nucleus collisions

    NASA Astrophysics Data System (ADS)

    Speranza, Enrico; Jaiswal, Amaresh; Friman, Bengt

    2018-07-01

    The polarization of virtual photons produced in relativistic nucleus-nucleus collisions provides information on the conditions in the emitting medium. In a hydrodynamic framework, the resulting angular anisotropy of the dilepton final state depends on the flow as well as on the transverse momentum and invariant mass of the photon. We illustrate these effects in dilepton production from quark-antiquark annihilation in the QGP phase and π+π- annihilation in the hadronic phase for a static medium in global equilibrium and for a longitudinally expanding system.

  3. Kaon-nucleus scattering

    NASA Technical Reports Server (NTRS)

    Hong, Byungsik; Buck, Warren W.; Maung, Khin M.

    1989-01-01

    Two kinds of number density distributions of the nucleus, harmonic well and Woods-Saxon models, are used with the t-matrix that is taken from the scattering experiments to find a simple optical potential. The parameterized two body inputs, which are kaon-nucleon total cross sections, elastic slope parameters, and the ratio of the real to imaginary part of the forward elastic scattering amplitude, are shown. The eikonal approximation was chosen as the solution method to estimate the total and absorptive cross sections for the kaon-nucleus scattering.

  4. Neural hijacking: action of high-frequency electrical stimulation on cortical circuits.

    PubMed

    Cheney, P D; Griffin, D M; Van Acker, G M

    2013-10-01

    Electrical stimulation of the brain was one of the first experimental methods applied to understanding brain organization and function and it continues as a highly useful method both in research and clinical applications. Intracortical microstimulation (ICMS) involves applying electrical stimuli through a microelectrode suitable for recording the action potentials of single neurons. ICMS can be categorized into single-pulse stimulation; high-frequency, short-duration stimulation; and high-frequency, long-duration stimulation. For clinical and experimental reasons, considerable interest focuses on the mechanism of neural activation by electrical stimuli. In this article, we discuss recent results suggesting that action potentials evoked in cortical neurons by high-frequency electrical stimulation do not sum with the natural, behaviorally related background activity; rather, high-frequency stimulation eliminates and replaces natural activity. We refer to this as neural hijacking. We propose that a major component of the mechanism underlying neural hijacking is excitation of axons by ICMS and elimination of natural spikes by antidromic collision with stimulus-driven spikes evoked at high frequency. Evidence also supports neural hijacking as an important mechanism underlying the action of deep brain stimulation in the subthalamic nucleus and its therapeutic effect in treating Parkinson's disease.

  5. High frequency stimulation abolishes thalamic network oscillations: an electrophysiological and computational analysis

    NASA Astrophysics Data System (ADS)

    Lee, Kendall H.; Hitti, Frederick L.; Chang, Su-Youne; Lee, Dongchul C.; Roberts, David W.; McIntyre, Cameron C.; Leiter, James C.

    2011-08-01

    Deep brain stimulation (DBS) of the thalamus has been demonstrated to be effective for the treatment of epilepsy. To investigate the mechanism of action of thalamic DBS, we examined the effects of high frequency stimulation (HFS) on spindle oscillations in thalamic brain slices from ferrets. We recorded intracellular and extracellular electrophysiological activity in the nucleus reticularis thalami (nRt) and in thalamocortical relay (TC) neurons in the lateral geniculate nucleus, stimulated the slice using a concentric bipolar electrode, and recorded the level of glutamate within the slice. HFS (100 Hz) of TC neurons generated excitatory post-synaptic potentials, increased the number of action potentials in both TC and nRt neurons, reduced the input resistance, increased the extracellular glutamate concentration, and abolished spindle wave oscillations. HFS of the nRt also suppressed spindle oscillations. In both locations, HFS was associated with significant and persistent elevation in extracellular glutamate levels and suppressed spindle oscillations for many seconds after the cessation of stimulation. We simulated HFS within a computational model of the thalamic network, and HFS also disrupted spindle wave activity, but the suppression of spindle activity was short-lived. Simulated HFS disrupted spindle activity for prolonged periods of time only after glutamate release and glutamate-mediated activation of a hyperpolarization-activated current (Ih) was incorporated into the model. Our results suggest that the mechanism of action of thalamic DBS as used in epilepsy may involve the prolonged release of glutamate, which in turn modulates specific ion channels such as Ih, decreases neuronal input resistance, and abolishes thalamic network oscillatory activity.

  6. Actomyosin contractility rotates the cell nucleus

    PubMed Central

    Kumar, Abhishek; Maitra, Ananyo; Sumit, Madhuresh; Ramaswamy, Sriram; Shivashankar, G. V.

    2014-01-01

    The cell nucleus functions amidst active cytoskeletal filaments, but its response to their contractile stresses is largely unexplored. We study the dynamics of the nuclei of single fibroblasts, with cell migration suppressed by plating onto micro-fabricated patterns. We find the nucleus undergoes noisy but coherent rotational motion. We account for this observation through a hydrodynamic approach, treating the nucleus as a highly viscous inclusion residing in a less viscous fluid of orientable filaments endowed with active stresses. Lowering actin contractility selectively by introducing blebbistatin at low concentrations drastically reduced the speed and coherence of the angular motion of the nucleus. Time-lapse imaging of actin revealed a correlated hydrodynamic flow around the nucleus, with profile and magnitude consistent with the results of our theoretical approach. Coherent intracellular flows and consequent nuclear rotation thus appear to be an intrinsic property of cells. PMID:24445418

  7. Low P sub T hadron-nucleus interactions

    NASA Technical Reports Server (NTRS)

    Holynski, R.; Wozniak, K.

    1985-01-01

    The possibility of describing hadron-nucleus (hA) interactions is discussed in terms of a number of independent collisions of the projectile inside the target nucleus. This multiple rescattering may occur on a particle or quark parton level. To investigate the characteristics of hA interactions as a function of antineutrinos advantage is taken of the correlation between the average number antineutrinos of collisions of the projectile inside the nucleus and the number Ng of fast protons ejected from the struck nucleus. The relation antineutrinos vs Ng obtained in antineutrinos was used. For a given target nucleus this allows the selection of interactions occurring at different impact parameters.

  8. Optogenetic stimulation of adrenergic C1 neurons causes sleep state-dependent cardiorespiratory stimulation and arousal with sighs in rats.

    PubMed

    Burke, Peter G R; Abbott, Stephen B G; Coates, Melissa B; Viar, Kenneth E; Stornetta, Ruth L; Guyenet, Patrice G

    2014-12-01

    The rostral ventrolateral medulla (RVLM) contains central respiratory chemoreceptors (retrotrapezoid nucleus, RTN) and the sympathoexcitatory, hypoxia-responsive C1 neurons. Simultaneous optogenetic stimulation of these neurons produces vigorous cardiorespiratory stimulation, sighing, and arousal from non-REM sleep. To identify the effects that result from selectively stimulating C1 cells. A Cre-dependent vector expressing channelrhodopsin 2 (ChR2) fused with enhanced yellow fluorescent protein or mCherry was injected into the RVLM of tyrosine hydroxylase (TH)-Cre rats. The response of ChR2-transduced neurons to light was examined in anesthetized rats. ChR2-transduced C1 neurons were photoactivated in conscious rats while EEG, neck muscle EMG, blood pressure (BP), and breathing were recorded. Most ChR2-expressing neurons (95%) contained C1 neuron markers and innervated the spinal cord. RTN neurons were not transduced. While the rats were under anesthesia, the C1 cells were faithfully activated by each light pulse up to 40 Hz. During quiet resting and non-REM sleep, C1 cell stimulation (20 s, 2-20 Hz) increased BP and respiratory frequency and produced sighs and arousal from non-REM sleep. Arousal was frequency-dependent (85% probability at 20 Hz). Stimulation during REM sleep increased BP, but had no effect on EEG or breathing. C1 cell-mediated breathing stimulation was occluded by hypoxia (12% FIO2), but was unchanged by 6% FiCO2. C1 cell stimulation reproduces most effects of acute hypoxia, specifically cardiorespiratory stimulation, sighs, and arousal. C1 cell activation likely contributes to the sleep disruption and adverse autonomic consequences of sleep apnea. During hypoxia (awake) or REM sleep, C1 cell stimulation increases BP but no longer stimulates breathing.

  9. Deep brain stimulation improves orthostatic regulation of patients with Parkinson disease.

    PubMed

    Stemper, B; Beric, A; Welsch, G; Haendl, T; Sterio, D; Hilz, M J

    2006-11-28

    To evaluate whether subthalamic nucleus (STN) stimulation has an effect on the orthostatic regulation of patients with Parkinson disease (PD), we studied cardiovascular regulation during on and off phases of STN stimulation. We examined 14 patients with PD (mean age 58.1 +/- 5.8 years, 4 women, 10 men) with bilateral STN stimulators. Patients underwent 3 minutes of head-up tilt (HUT) testing during STN stimulation and after 90 minutes interruption of stimulation. We monitored arterial blood pressure (BP), RR intervals (RRI), respiration, and skin blood flow (SBF). Baroreflex sensitivity (BRS) was assessed as the square root of the ratio of low-frequency power of RRI to the low-frequency power of systolic BP for coherences above 0.5. During the on phase of the STN stimulation, HUT induced no BP decrease, a significant tachycardia, and a significant decrease of SBF. During the off phase of stimulation, HUT resulted in significant decreases in BPsys and RRI and only a slight SBF decrease. HUT induced no change of BRS during stimulation, but lowered BRS when the stimulator was off (p < 0.05). STN stimulation of patients with PD increases peripheral vasoconstriction and BRS and stabilizes BP, thereby improving postural hypotension in patients with PD. The results indicate that STN stimulation not only alleviates motor deficits but also influences autonomic regulation in patients with PD.

  10. Population calcium imaging of spontaneous respiratory and novel motor activity in the facial nucleus and ventral brainstem in newborn mice

    PubMed Central

    Persson, Karin; Rekling, Jens C

    2011-01-01

    Abstract The brainstem contains rhythm and pattern forming circuits, which drive cranial and spinal motor pools to produce respiratory and other motor patterns. Here we used calcium imaging combined with nerve recordings in newborn mice to reveal spontaneous population activity in the ventral brainstem and in the facial nucleus. In Fluo-8 AM loaded brainstem–spinal cord preparations, respiratory activity on cervical nerves was synchronized with calcium signals at the ventrolateral brainstem surface. Individual ventrolateral neurons at the level of the parafacial respiratory group showed perfect or partial synchrony with respiratory nerve bursts. In brainstem–spinal cord preparations, cut at the level of the mid-facial nucleus, calcium signals were recorded in the dorsal, lateral and medial facial subnuclei during respiratory activity. Strong activity initiated in the dorsal subnucleus, followed by activity in lateral and medial subnuclei. Whole-cell recordings from facial motoneurons showed weak respiratory drives, and electrical field potential recordings confirmed respiratory drive to particularly the dorsal and lateral subnuclei. Putative facial premotoneurons showed respiratory-related calcium signals, and were predominantly located dorsomedial to the facial nucleus. A novel motor activity on facial, cervical and thoracic nerves was synchronized with calcium signals at the ventromedial brainstem extending from the level of the facial nucleus to the medulla–spinal cord border. Cervical dorsal root stimulation induced similar ventromedial activity. The medial facial subnucleus showed calcium signals synchronized with this novel motor activity on cervical nerves, and cervical dorsal root stimulation induced similar medial facial subnucleus activity. In conclusion, the dorsal and lateral facial subnuclei are strongly respiratory-modulated, and the brainstem contains a novel pattern forming circuit that drives the medial facial subnucleus and cervical motor

  11. Radiant energy required for infrared neural stimulation

    DOE PAGES

    Tan, Xiaodong; Rajguru, Suhrud; Young, Hunter; ...

    2015-08-25

    Infrared neural stimulation (INS) has been proposed as an alternative method to electrical stimulation because of its spatial selective stimulation. Independent of the mechanism for INS, to translate the method into a device it is important to determine the energy for stimulation required at the target structure. Custom-designed, flat and angle polished fibers, were used to deliver the photons. By rotating the angle polished fibers, the orientation of the radiation beam in the cochlea could be changed. INS-evoked compound action potentials and single unit responses in the central nucleus of the inferior colliculus (ICC) were recorded. X-ray computed tomography wasmore » used to determine the orientation of the optical fiber. Maximum responses were observed when the radiation beam was directed towards the spiral ganglion neurons (SGNs), whereas little responses were seen when the beam was directed towards the basilar membrane. The radiant exposure required at the SGNs to evoke compound action potentials (CAPs) or ICC responses was on average 18.9 ± 12.2 or 10.3 ± 4.9 mJ/cm 2, respectively. For cochlear INS it has been debated whether the radiation directly stimulates the SGNs or evokes a photoacoustic effect. The results support the view that a direct interaction between neurons and radiation dominates the response to INS.« less

  12. Radiant energy required for infrared neural stimulation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tan, Xiaodong; Rajguru, Suhrud; Young, Hunter

    Infrared neural stimulation (INS) has been proposed as an alternative method to electrical stimulation because of its spatial selective stimulation. Independent of the mechanism for INS, to translate the method into a device it is important to determine the energy for stimulation required at the target structure. Custom-designed, flat and angle polished fibers, were used to deliver the photons. By rotating the angle polished fibers, the orientation of the radiation beam in the cochlea could be changed. INS-evoked compound action potentials and single unit responses in the central nucleus of the inferior colliculus (ICC) were recorded. X-ray computed tomography wasmore » used to determine the orientation of the optical fiber. Maximum responses were observed when the radiation beam was directed towards the spiral ganglion neurons (SGNs), whereas little responses were seen when the beam was directed towards the basilar membrane. The radiant exposure required at the SGNs to evoke compound action potentials (CAPs) or ICC responses was on average 18.9 ± 12.2 or 10.3 ± 4.9 mJ/cm 2, respectively. For cochlear INS it has been debated whether the radiation directly stimulates the SGNs or evokes a photoacoustic effect. The results support the view that a direct interaction between neurons and radiation dominates the response to INS.« less

  13. On the functional anatomy of the nucleus of the optic tract-dorsal terminal nucleus commissural connection in the opossum (Didelphis marsupialis aurita).

    PubMed

    Vargas, C D; Volchan, E; Hokoç, J N; Pereira, A; Bernardes, R F; Rocha-Miranda, C E

    1997-01-01

    Immunocytochemical methods revealed the presence of GABA in cell bodies and terminals in the nucleus of the optic tract-dorsal terminal nucleus, the medial terminal nucleus, the lateral terminal nucleus and the interstitial nucleus of the superior fasciculus of the opossum (Didelphis marsupialis aurita). Moreover, after unilateral injections of rhodamine beads in the nucleus of the optic tract-dorsal terminal nucleus complex and processing for GABA, double-labelled cells were detected in the ipsilateral complex, up to 400 microns from the injected site, but not in the opposite. Analysis of the distributions of GABAergic and retrogradely-labelled cells throughout the contralateral nucleus of the optic tract-dorsal terminal nucleus showed that the highest density of GABAergic and rhodamine-labelled cells overlapped at the middle third of the complex. Previous electrophysiological data obtained in the opossum had suggested the existence, under certain conditions, of an inhibitory action between the nucleus of the optic tract-dorsal terminal nucleus of one side over the other. The absence of GABAergic commissural neurons may imply that this inhibition is mediated by an excitatory commissural pathway that activates GABAergic interneurons.

  14. Multicontrast multiecho FLASH MRI for targeting the subthalamic nucleus.

    PubMed

    Xiao, Yiming; Beriault, Silvain; Pike, G Bruce; Collins, D Louis

    2012-06-01

    The subthalamic nucleus (STN) is one of the most common stimulation targets for treating Parkinson's disease using deep brain stimulation (DBS). This procedure requires precise placement of the stimulating electrode. Common practice of DBS implantation utilizes microelectrode recording to locate the sites with the correct electrical response after an initial location estimate based on a universal human brain atlas that is linearly scaled to the patient's anatomy as seen on the preoperative images. However, this often results in prolonged surgical time and possible surgical complications since the small-sized STN is difficult to visualize on conventional magnetic resonance (MR) images and its intersubject variability is not sufficiently considered in the atlas customization. This paper proposes a multicontrast, multiecho MR imaging (MRI) method that directly delineates the STN and other basal ganglia structures through five co-registered image contrasts (T1-weighted navigation image, R2 map, susceptibility-weighted imaging (phase, magnitude and fusion image)) obtained within a clinically acceptable time. The image protocol was optimized through both simulation and in vivo experiments to obtain the best image quality. Taking advantage of the multiple echoes and high readout bandwidths, no interimage registration is required since all images are produced in one acquisition, and image distortion and chemical shift are reduced. This MRI protocol is expected to mitigate some of the shortcomings of the state-of-the-art DBS implantation methods. Copyright © 2012 Elsevier Inc. All rights reserved.

  15. Effect of bilateral stimulation of the subthalamic nucleus on different speech subsystems in patients with Parkinson's disease.

    PubMed

    Pützer, Manfred; Barry, William J; Moringlane, Jean Richard

    2008-12-01

    The effect of deep brain stimulation on the two speech-production subsystems, articulation and phonation, of nine Parkinsonian patients is examined. Production parameters (stop closure voicing; stop closure, VOT, vowel) in fast syllable-repetitions were defined and measured and quantitative, objective metrics of vocal fold function were obtained during vowel production. Speech material was recorded for patients (with and without stimulation) and for a reference group of healthy control speakers. With stimulation, precision of the glottal and supraglottal articulation as well as the phonatory function is reduced for some individuals, whereas for other individuals an improvement is observed. Importantly, the improvement or deterioration is determined not only on the basis of the direction of parameter change but also on the individuals' position relative to the healthy control data. This study also notes differences within an individual in the effects of stimulation on the two speech subsystems. These findings qualify the value of global statements about the effect of neurostimulatory operations on Parkinsonian patients. They also underline the importance of careful consideration of individual differences in the effect of deep brain stimulation on different speech subsystems.

  16. Gallic acid inhibits the release of ADAMTS4 in nucleus pulposus cells by inhibiting p65 phosphorylation and acetylation of the NF-κB signaling pathway.

    PubMed

    Huang, Yao; Chen, Jian; Jiang, Tao; Zhou, Zheng; Lv, Bin; Yin, Guoyong; Fan, Jin

    2017-07-18

    This study investigated the inhibitory effect of gallic acid (GA) on the release of A Disintegrin and Metalloproteinase with Thrombospondin motifs 4 (ADAMTS4) through the regulation of the NF-κB signaling pathway, which is closely related to the matrix metalloproteinases in nucleus pulposus cells. Different concentrations of GA were added to TNF-α-induced human nucleus pulposus cells (hNPCs) and intervertebral disc degeneration rat model. ADAMTS-4 expression increased both in the TNF-α-induced nucleus pulposus cells and intervertebral disc degeneration rat model. By contrast, the release of ADAMTS-4 was reduced, and the TNF-α-induced apoptosis of nucleus pulposus cells was significantly inhibited after addition of GA at different concentrations. Further study found that the levels of phosphorylated p65 (p-p65) was increased and the classical NF-κB signal pathway was activated after the nucleus pulposus cells were stimulated by TNF-α. Meanwhile, GA suppressed the p65 phosphorylation and inceased p65 deacetylation levels. As a consequence, GA can decrease the expression of ADAMTS-4 in nucleus pulposus cells by regulating the phosphorylation and acetylation of p65 in NF-κB signaling pathways.

  17. High-Frequency Stimulation of the Subthalamic Nucleus Activates Motor Cortex Pyramidal Tract Neurons by a Process Involving Local Glutamate, GABA and Dopamine Receptors in Hemi-Parkinsonian Rats.

    PubMed

    Chuang, Chi-Fen; Wu, Chen-Wei; Weng, Ying; Hu, Pei-San; Yeh, Shin-Rung; Chang, Yen-Chung

    2018-04-30

    Deep brain stimulation (DBS) is widely used to treat advanced Parkinson’s disease (PD). Here, we investigated how DBS applied on the subthalamic nucleus (STN) influenced the neural activity in the motor cortex. Rats, which had the midbrain dopaminergic neurons partially depleted unilaterally, called the hemi-Parkinsonian rats, were used as a study model. c-Fos expression in the neurons was used as an indicator of neural activity. Application of high-frequency stimulation (HFS) upon the STN was used to mimic the DBS treatment. The motor cortices in the two hemispheres of hemi-Parkinsonian rats were found to contain unequal densities of c-Fos-positive (Fos+) cells, and STN-HFS rectified this bilateral imbalance. In addition, STN-HFS led to the intense c-Fos expression in a group of motor cortical neurons which exhibited biochemical and anatomical characteristics resembling those of the pyramidal tract (PT) neurons sending efferent projections to the STN. The number of PT neurons expressing high levels of c-Fos was significantly reduced by local application of the antagonists of non-N-methyl-D-aspartate (non-NMDA) glutamate receptors, gammaaminobutyric acid A (GABAA) receptors and dopamine receptors in the upper layers of the motor cortex. The results indicate that the coincident activations of synapses and dopamine receptors in the motor cortex during STN-HFS trigger the intense expression of c-Fos of the PT neurons. The implications of the results on the cellular mechanism underlying the therapeutic effects of STN-DBS on the movement disorders of PD are also discussed.

  18. Transverse limited phase space model with Glauber geometry for high-energy nucleus-nucleus collisions

    NASA Astrophysics Data System (ADS)

    Huang, Ding Wei; Yen, Edward

    1989-08-01

    We propose a detailed model, combining the concepts from a partition temperature model and wounded nucleon model, to describe high-energy nucleus-nucleus collisions. One partition temperature is associated with collisions at a fixed wounded nucleon number. The (pseudo-) rapidity distributions are calculated and compared with experimental data. Predictions at higher energy are also presented.

  19. Development-dependent behavioral change toward pups and synaptic transmission in the rhomboid nucleus of the bed nucleus of the stria terminalis.

    PubMed

    Amano, Taiju; Shindo, Sayaka; Yoshihara, Chihiro; Tsuneoka, Yousuke; Uki, Haruka; Minami, Masabumi; Kuroda, Kumi O

    2017-05-15

    Sexually naïve male C57BL/6 mice aggressively bite unfamiliar pups. This behavior, called infanticide, is considered an adaptive reproductive strategy of males of polygamous species. We recently found that the rhomboid nucleus of the bed nucleus of the stria terminalis (BSTrh) is activated during infanticide and that the bilateral excitotoxic lesions of BSTrh suppress infanticidal behavior. Here we show that 3-week-old male C57BL/6 mice rarely engaged in infanticide and instead, provided parental care toward unfamiliar pups, consistent with observations in rats and other rodent species. This inhibition of infanticide at the periweaning period is functional because the next litter will be born at approximately the time of weaning of the previous litter through maternal postpartum ovulation. However, the mechanism of this age-dependent behavioral change is unknown. Therefore, we performed whole-cell patch clamp recordings of BSTrh and compared evoked neurotransmission in response to the stimulation of the stria terminalis of adult and 3-week-old male mice. Although we were unable to detect a significant difference in the amplitudes of inhibitory neurotransmission, the amplitudes and the paired-pulse ratio of evoked excitatory postsynaptic currents differed between adult and 3-week-old mice. These data suggest that maturation of the synaptic terminal in BSTrh that occurred later than 3 weeks after birth may mediate by the adaptive change from parental to infanticidal behavior in male mice. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Sufficiency of Mesolimbic Dopamine Neuron Stimulation for the Progression to Addiction.

    PubMed

    Pascoli, Vincent; Terrier, Jean; Hiver, Agnès; Lüscher, Christian

    2015-12-02

    The factors causing the transition from recreational drug consumption to addiction remain largely unknown. It has not been tested whether dopamine (DA) is sufficient to trigger this process. Here we use optogenetic self-stimulation of DA neurons of the ventral tegmental area (VTA) to selectively mimic the defining commonality of addictive drugs. All mice readily acquired self-stimulation. After weeks of abstinence, cue-induced relapse was observed in parallel with a potentiation of excitatory afferents onto D1 receptor-expressing neurons of the nucleus accumbens (NAc). When the mice had to endure a mild electric foot shock to obtain a stimulation, some stopped while others persevered. The resistance to punishment was associated with enhanced neural activity in the orbitofrontal cortex (OFC) while chemogenetic inhibition of the OFC reduced compulsivity. Together, these results show that stimulating VTA DA neurons induces behavioral and cellular hallmarks of addiction, indicating sufficiency for the induction and progression of the disease. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Optimal control of directional deep brain stimulation in the parkinsonian neuronal network

    NASA Astrophysics Data System (ADS)

    Fan, Denggui; Wang, Zhihui; Wang, Qingyun

    2016-07-01

    The effect of conventional deep brain stimulation (DBS) on debilitating symptoms of Parkinson's disease can be limited because it can only yield the spherical field. And, some side effects are clearly induced with influencing their adjacent ganglia. Recent experimental evidence for patients with Parkinson's disease has shown that a novel DBS electrode with 32 independent stimulation source contacts can effectively optimize the clinical therapy by enlarging the therapeutic windows, when it is applied on the subthalamic nucleus (STN). This is due to the selective activation in clusters of various stimulation contacts which can be steered directionally and accurately on the targeted regions of interest. In addition, because of the serious damage to the neural tissues, the charge-unbalanced stimulation is not typically indicated and the real DBS utilizes charge-balanced bi-phasic (CBBP) pulses. Inspired by this, we computationally investigate the optimal control of directional CBBP-DBS from the proposed parkinsonian neuronal network of basal ganglia-thalamocortical circuit. By appropriately tuning stimulation for different neuronal populations, it can be found that directional steering CBBP-DBS paradigms are superior to the spherical case in improving parkinsonian dynamical properties including the synchronization of neuronal populations and the reliability of thalamus relaying the information from cortex, which is in a good agreement with the physiological experiments. Furthermore, it can be found that directional steering stimulations can increase the optimal stimulation intensity of desynchronization by more than 1 mA compared to the spherical case. This is consistent with the experimental result with showing that there exists at least one steering direction that can allow increasing the threshold of side effects by 1 mA. In addition, we also simulate the local field potential (LFP) and dominant frequency (DF) of the STN neuronal population induced by the activation

  2. Localization of beta and high-frequency oscillations within the subthalamic nucleus region.

    PubMed

    van Wijk, B C M; Pogosyan, A; Hariz, M I; Akram, H; Foltynie, T; Limousin, P; Horn, A; Ewert, S; Brown, P; Litvak, V

    2017-01-01

    Parkinsonian bradykinesia and rigidity are typically associated with excessive beta band oscillations in the subthalamic nucleus. Recently another spectral peak has been identified that might be implicated in the pathophysiology of the disease: high-frequency oscillations (HFO) within the 150-400 Hz range. Beta-HFO phase-amplitude coupling (PAC) has been found to correlate with severity of motor impairment. However, the neuronal origin of HFO and its usefulness as a potential target for deep brain stimulation remain to be established. For example, it is unclear whether HFO arise from the same neural populations as beta oscillations. We intraoperatively recorded local field potentials from the subthalamic nucleus while advancing DBS electrodes in 2 mm steps from 4 mm above the surgical target point until 2 mm below, resulting in 4 recording sites. Data from 26 nuclei from 14 patients were analysed. For each trajectory, we identified the recording site with the largest spectral peak in the beta range (13-30 Hz), and the largest peak in the HFO range separately. In addition, we identified the recording site with the largest beta-HFO PAC. Recording sites with largest beta power and largest HFO power coincided in 50% of cases. In the other 50%, HFO was more likely to be detected at a more superior recording site in the target area. PAC followed more closely the site with largest HFO (45%) than beta power (27%). HFO are likely to arise from spatially close, but slightly more superior neural populations than beta oscillations. Further work is necessary to determine whether the different activities can help fine-tune deep brain stimulation targeting.

  3. Comet encke: radar detection of nucleus.

    PubMed

    Kamoun, P G; Campbell, D B; Ostro, S J; Pettengill, G H; Shapiro, I I

    1982-04-16

    The nucleus of the periodic comet Encke was detected in November 1980 with the Arecibo Observatory's radar system (wavelength, 12.6 centimeters). The echoes in the one sense of circular polarization received imply a radar cross section of 1.1 +/- 0.7 square kilometers. The estimated bandwidth of these echoes combined with an estimate of the rotation vector of Encke yields a radius for the nucleus of l.5(+2.3)(-1.0) kilometers. The uncertainties given are dependent primarily on the range of models considered for the comet and for the manner in which its nucleus backscatters radio waves. Should this range prove inadequate, the true value of the radius of the nucleus might lie outside the limits given.

  4. Single-prolonged stress induces apoptosis in dorsal raphe nucleus in the rat model of posttraumatic stress disorder

    PubMed Central

    2012-01-01

    Introduction Post-traumatic stress disorder (PTSD) is an anxiety disorder that develops after exposure to a life-threatening traumatic experience. Meta-analyses of the brainstem showed that midsagittal area of the pons was significantly reduced in patients with PTSD, suggesting a potential apoptosis in dorsal raphe nucleus after single-prolonged stress (SPS). The aim of this study is to investigate whether SPS induces apoptosis in dorsal raphe nucleus in PTSD rats, which may be a possible mechanism of reduced volume of pons and density of gray matter. Methods In this study, rats were randomly divided into 1d, 7d and 14d groups after SPS along with the control group. The apoptosis rate was determined using annexin V-FITC/PI double-labeled flow cytometry (FCM). Levels of Cytochrome c (Cyt-C) was examined by Western blotting. Expression of Cyt-C on mitochondria in the dorsal raphe nucleus neuron was determined by enzymohistochemistry under transmission electron microscopy (TEM). The change of thiamine monophosphatase (TMP) levels was assessed by enzymohistochemistry under light microscope and TEM. Morphological changes of the ultrastructure of the dorsal raphe nucleus neuron were determined by TEM. Results Apoptotic morphological alterations were observed in dorsal raphe nucleus neuron for all SPS-stimulate groups of rats. The apoptosis rates were significantly increased in dorsal raphe nucleus neuron of SPS rats, along with increased release of cytochrome c from the mitochondria into the cytoplasm, increased expression of Cyt-C and TMP levels in the cytoplasm, which reached to the peak of increase 7 days of SPS. Conclusions The results indicate that SPS induced Cyt-C released from mitochondria into cytosol and apoptosis in dorsal raphe nucleus neuron of rats. Increased TMP in cytoplasm facilitated the clearance of apoptotic cells. We propose that this presents one of the mechanisms that lead to reduced volume of pons and gray matter associated with PTSD. PMID

  5. Nucleus accumbens deep-brain stimulation efficacy in ACTH-pretreated rats: alterations in mitochondrial function relate to antidepressant-like effects

    PubMed Central

    Kim, Y; McGee, S; Czeczor, J K; Walker, A J; Kale, R P; Kouzani, A Z; Walder, K; Berk, M; Tye, S J

    2016-01-01

    Mitochondrial dysfunction has a critical role in the pathophysiology of mood disorders and treatment response. To investigate this, we established an animal model exhibiting a state of antidepressant treatment resistance in male Wistar rats using 21 days of adrenocorticotropic hormone (ACTH) administration (100 μg per day). First, the effect of ACTH treatment on the efficacy of imipramine (10 mg kg−1) was investigated alongside its effect on the prefrontal cortex (PFC) mitochondrial function. Second, we examined the mood-regulatory actions of chronic (7 day) high-frequency nucleus accumbens (NAc) deep-brain stimulation (DBS; 130 Hz, 100 μA, 90 μS) and concomitant PFC mitochondrial function. Antidepressant-like responses were assessed in the open field test (OFT) and forced swim test (FST) for both conditions. ACTH pretreatment prevented imipramine-mediated improvement in mobility during the FST (P<0.05). NAc DBS effectively improved FST mobility in ACTH-treated animals (P<0.05). No improvement in mobility was observed for sham control animals (P>0.05). Analyses of PFC mitochondrial function revealed that ACTH-treated animals had decreased capacity for adenosine triphosphate production compared with controls. In contrast, ACTH animals following NAc DBS demonstrated greater mitochondrial function relative to controls. Interestingly, a proportion (30%) of the ACTH-treated animals exhibited heightened locomotor activity in the OFT and exaggerated escape behaviors during the FST, together with general hyperactivity in their home-cage settings. More importantly, the induction of this mania-like phenotype was accompanied by overcompensative increased mitochondrial respiration. Manifestation of a DBS-induced mania-like phenotype in imipramine-resistant animals highlights the potential use of this model in elucidating mechanisms of mood dysregulation. PMID:27327257

  6. Prolonged Stimulation of a Brainstem Raphe Region Attenuates Experimental Autoimmune Encephalomyelitis

    PubMed Central

    Madsen, Pernille M.; Sloley, Stephanie S.; Vitores, Alberto A.; Carballosa-Gautam, Melissa M.; Brambilla, Roberta; Hentall, Ian D.

    2017-01-01

    Multiple sclerosis (MS), a neuroinflammatory disease, has few treatment options, none entirely adequate. We studied whether prolonged electrical stimulation of a hindbrain region (the nucleus raphe magnus) can attenuate experimental autoimmune encephalomyelitis, a murine model of MS induced by MOG35-55 injection. Eight days after symptoms emerged, a wireless electrical stimulator with a connectorless protruding microelectrode was implanted cranially, and daily intermittent stimulation of awake, unrestrained mice began immediately. The thoracic spinal cord was analyzed for changes in histology (on day 29) and gene expression (on day 37), with a focus on myelination and cytokine production. Controls, with inactive implants, showed a phase of disease exacerbation on days 19–25 that stimulation for >16 days eliminated. Prolonged stimulation also reduced infiltrating immune cells and increased numbers of myelinated axons. It additionally lowered gene expression for some pro-inflammatory cytokines (interferon gamma and tumor necrosis factor) and for platelet-derived growth factor receptor alpha, a marker of oligodendrocyte precursors, while raising it for myelin basic protein. Restorative treatments for MS might profitably consider ways to stimulate the raphe magnus, directly or via its inputs, or to emulate its serotonergic and peptidergic output. PMID:28147248

  7. A search for ϕ meson nucleus bound state using antiproton annihilation on nucleus

    NASA Astrophysics Data System (ADS)

    Ohnishi, H.; Bühler, P.; Cargnelli, M.; Curceanu, C.; Guaraldo, C.; Hartmann, O.; Hicks, K.; Iwasaki, M.; Ishiwatari, T.; Kienle, P.; Marton, J.; Muto, R.; Naruki, M.; Niiyama, M.; Noumi, H.; Okada, S.; Vidal, A. Romero; Sakaguchi, A.; Sakuma, F.; Sawada, S.; Sirghi, D.; Sirghi, F.; Suzuki, K.; Tsukada, K.; Doce, O. Vazquez; Widmann, E.; Yokkaichi, S.; Zmeskal, J.

    2012-12-01

    The mass shift of the vector mesons in nuclei is known to be a powerful tool for investigating the mechanism of generating hadron mass from the QCD vacuum. The mechanism is known to be the spontaneous breaking of chiral symmetry. In 2007, KEK-PS E325 experiment reported about 3.4 % mass reduction of the ϕ meson in medium-heavy nuclei (Cu). This result is possibly one of the indications of the partial restoration of chiral symmetry in nuclei, however, unfortunately it is hard to make strong conclusions from the data. One of the ways to conclude the strength of the ϕ meson mass shift in nuclei will be by trying to produce only slowly moving ϕ mesons where the maximum nuclear matter effect can be probed. The observed mass reduction of the ϕ meson in the nucleus can be translated as the existence of an attractive force between ϕ meson and nucleus. Thus, one of the extreme conditions that can be achieved in the laboratory is indeed the formation of a ϕ-nucleus bound state, where the ϕ meson is "trapped" in the nucleus. The purpose of the experiment is to search for a ϕ-nucleus bound state and measure the binding energy of the system. We will demonstrate that a completely background-free missing-mass spectrum can be obtained efficiently by (bar{p}, φ) spectroscopy together with K + Λ tagging, using the primary reaction channel bar{p} p rightarrow φ φ. This paper gives an overview of the physics motivation and the detector concept, and explains the direction of the initial research and development effort.

  8. A search for ϕ meson nucleus bound state using antiproton annihilation on nucleus

    NASA Astrophysics Data System (ADS)

    Ohnishi, H.; Bühler, P.; Cargnelli, M.; Curceanu, C.; Guaraldo, C.; Hartmann, O.; Hicks, K.; Iwasaki, M.; Ishiwatari, T.; Kienle, P.; Marton, J.; Muto, R.; Naruki, M.; Niiyama, M.; Noumi, H.; Okada, S.; Vidal, A. Romero; Sakaguchi, A.; Sakuma, F.; Sawada, S.; Sirghi, D.; Sirghi, F.; Suzuki, K.; Tsukada, K.; Doce, O. Vazquez; Widmann, E.; Yokkaichi, S.; Zmeskal, J.

    The mass shift of the vector mesons in nuclei is known to be a powerful tool for investigating the mechanism of generating hadron mass from the QCD vacuum. The mechanism is known to be the spontaneous breaking of chiral symmetry. In 2007, KEK-PS E325 experiment reported about 3.4 % mass reduction of the ϕ meson in medium-heavy nuclei (Cu). This result is possibly one of the indications of the partial restoration of chiral symmetry in nuclei, however, unfortunately it is hard to make strong conclusions from the data. One of the ways to conclude the strength of the ϕ meson mass shift in nuclei will be by trying to produce only slowly moving ϕ mesons where the maximum nuclear matter effect can be probed. The observed mass reduction of the ϕ meson in the nucleus can be translated as the existence of an attractive force between ϕ meson and nucleus. Thus, one of the extreme conditions that can be achieved in the laboratory is indeed the formation of a ϕ-nucleus bound state, where the ϕ meson is "trapped" in the nucleus. The purpose of the experiment is to search for a ϕ-nucleus bound state and measure the binding energy of the system. We will demonstrate that a completely background-free missing-mass spectrum can be obtained efficiently by (bar{p}, φ) spectroscopy together with K + Λ tagging, using the primary reaction channel bar{p} p rightarrow φ φ. This paper gives an overview of the physics motivation and the detector concept, and explains the direction of the initial research and development effort.

  9. Distinct populations of neurons respond to emotional valence and arousal in the human subthalamic nucleus.

    PubMed

    Sieger, Tomáš; Serranová, Tereza; Růžička, Filip; Vostatek, Pavel; Wild, Jiří; Štastná, Daniela; Bonnet, Cecilia; Novák, Daniel; Růžička, Evžen; Urgošík, Dušan; Jech, Robert

    2015-03-10

    Both animal studies and studies using deep brain stimulation in humans have demonstrated the involvement of the subthalamic nucleus (STN) in motivational and emotional processes; however, participation of this nucleus in processing human emotion has not been investigated directly at the single-neuron level. We analyzed the relationship between the neuronal firing from intraoperative microrecordings from the STN during affective picture presentation in patients with Parkinson's disease (PD) and the affective ratings of emotional valence and arousal performed subsequently. We observed that 17% of neurons responded to emotional valence and arousal of visual stimuli according to individual ratings. The activity of some neurons was related to emotional valence, whereas different neurons responded to arousal. In addition, 14% of neurons responded to visual stimuli. Our results suggest the existence of neurons involved in processing or transmission of visual and emotional information in the human STN, and provide evidence of separate processing of the affective dimensions of valence and arousal at the level of single neurons as well.

  10. Auditory cortex stimulation to suppress tinnitus: mechanisms and strategies.

    PubMed

    Zhang, Jinsheng

    2013-01-01

    Brain stimulation is an important method used to modulate neural activity and suppress tinnitus. Several auditory and non-auditory brain regions have been targeted for stimulation. This paper reviews recent progress on auditory cortex (AC) stimulation to suppress tinnitus and its underlying neural mechanisms and stimulation strategies. At the same time, the author provides his opinions and hypotheses on both animal and human models. The author also proposes a medial geniculate body (MGB)-thalamic reticular nucleus (TRN)-Gating mechanism to reflect tinnitus-related neural information coming from upstream and downstream projection structures. The upstream structures include the lower auditory brainstem and midbrain structures. The downstream structures include the AC and certain limbic centers. Both upstream and downstream information is involved in a dynamic gating mechanism in the MGB together with the TRN. When abnormal gating occurs at the thalamic level, the spilled-out information interacts with the AC to generate tinnitus. The tinnitus signals at the MGB-TRN-Gating may be modulated by different forms of stimulations including brain stimulation. Each stimulation acts as a gain modulator to control the level of tinnitus signals at the MGB-TRN-Gate. This hypothesis may explain why different types of stimulation can induce tinnitus suppression. Depending on the tinnitus etiology, MGB-TRN-Gating may be different in levels and dynamics, which cause variability in tinnitus suppression induced by different gain controllers. This may explain why the induced suppression of tinnitus by one type of stimulation varies across individual patients. Copyright © 2012. Published by Elsevier B.V.

  11. Modern management of epilepsy: Vagus nerve stimulation.

    PubMed

    Ben-Menachem, E

    1996-12-01

    Vagus nerve stimulation (VNS) was first tried as a treatment for seizure patients in 1988. The idea to stimulate the vagus nerve and disrupt or prevent seizures was proposed by Jacob Zabarra. He observed a consistent finding among several animal studies which indicated that stimulation of the vagus nerve could alter the brain wave patterns of the animals under study. His hypothesis formed the basis for the development of the vagus nerve stimulator, an implantable device similar to a pacemaker, which is implanted in the left chest and attached to the left vagus nerve via a stimulating lead. Once implanted, the stimulator is programmed by a physician to deliver regular stimulation 24 hours a day regardless of seizure activity. Patients can also activate extra 'on-demand' stimulation with a handheld magnet. Clinical studies have demonstrated VNS therapy to be a safe and effective mode of treatment when added to the existing regimen of severe, refractory patients with epilepsy. Efficacy ranges from seizure free to no response with the majority of patients (> 50%) reporting at least a 50% improvement in number of seizures after 1.5 years of treatment. The side-effect profile is unique and mostly includes stimulation-related sensations in the neck and throat. The mechanism of action for VNS is not clearly understood although two theories have emerged. First, the direct connection theory hypothesizes that the anticonvulsant action of VNS is caused by a threshold raising effect of the connections to the nucleus of the solitary tract and on to other structures. The second is the concept that chronic stimulation of the vagus nerve increases the amount of inhibitory neurotransmitters and decreases the amount of excitatory neurotransmitters. Additional research into the optimal use of VNS is ongoing. Animal and clinical research have produced some interesting new data suggesting there are numerous ways to improve the clinical performance of vagus nerve stimulation as a

  12. Abnormal oxygen homeostasis in the nucleus tractus solitarii of the spontaneously hypertensive rat.

    PubMed

    Hosford, Patrick S; Millar, Julian; Ramage, Andrew G; Marina, Nephtali

    2017-04-01

    What is the central question of this study? Arterial hypertension is associated with impaired neurovascular coupling in the somatosensory cortex. Abnormalities in activity-dependent oxygen consumption in brainstem regions involved in the control of cardiovascular reflexes have not been explored previously. What is the main finding and its importance? Using fast-cyclic voltammetry, we found that changes in local tissue PO2 in the nucleus tractus solitarii induced by electrical stimulation of the vagus nerve are significantly impaired in spontaneously hypertensive rats. This is consistent with previous observations showing that brainstem hypoxia plays an important role in the pathogenesis of arterial hypertension. The effects of arterial hypertension on cerebral blood flow remain poorly understood. Haemodynamic responses within the somatosensory cortex have been shown to be impaired in the spontaneously hypertensive rat (SHR) model. However, it is unknown whether arterial hypertension affects oxygen homeostasis in vital brainstem areas that control cardiovascular reflexes. In this study, we assessed vagus nerve stimulation-induced changes in local tissue PO2 (PtO2) in the caudal nucleus tractus solitarii (cNTS) of SHRs and normotensive Wistar rats. Measurements of PtO2 were performed using a novel application of fast-cyclic voltammetry, which allows higher temporal resolution of O 2 changes than traditional optical fluorescence techniques. Electrical stimulation of the central cut end of the vagus nerve (ESVN) caused profound reductions in arterial blood pressure along with biphasic changes in PtO2 in the cNTS, characterized by a rapid decrease in PtO2 ('initial dip') followed by a post-stimulus overshoot above baseline. The initial dip was found to be significantly smaller in SHRs compared with normotensive Wistar rats even after ganglionic blockade. The post-ESVN overshoot was similar in both groups but was reduced in Wistar rats after ganglionic blockade. In

  13. Acoustic Overexposure Increases the Expression of VGLUT-2 Mediated Projections from the Lateral Vestibular Nucleus to the Dorsal Cochlear Nucleus

    PubMed Central

    Barker, Matthew; Solinski, Hans Jürgen; Hashimoto, Haruka; Tagoe, Thomas; Pilati, Nadia; Hamann, Martine

    2012-01-01

    The dorsal cochlear nucleus (DCN) is a first relay of the central auditory system as well as a site for integration of multimodal information. Vesicular glutamate transporters VGLUT-1 and VGLUT-2 selectively package glutamate into synaptic vesicles and are found to have different patterns of organization in the DCN. Whereas auditory nerve fibers predominantly co-label with VGLUT-1, somatosensory inputs predominantly co-label with VGLUT-2. Here, we used retrograde and anterograde transport of fluorescent conjugated dextran amine (DA) to demonstrate that the lateral vestibular nucleus (LVN) exhibits ipsilateral projections to both fusiform and deep layers of the rat DCN. Stimulating the LVN induced glutamatergic synaptic currents in fusiform cells and granule cell interneurones. We combined the dextran amine neuronal tracing method with immunohistochemistry and showed that labeled projections from the LVN are co-labeled with VGLUT-2 by contrast to VGLUT-1. Wistar rats were exposed to a loud single tone (15 kHz, 110 dB SPL) for 6 hours. Five days after acoustic overexposure, the level of expression of VGLUT-1 in the DCN was decreased whereas the level of expression of VGLUT-2 in the DCN was increased including terminals originating from the LVN. VGLUT-2 mediated projections from the LVN to the DCN are likely to play a role in the head position in response to sound. Amplification of VGLUT-2 expression after acoustic overexposure could be a compensatory mechanism from vestibular inputs in response to hearing loss and to a decrease of VGLUT-1 expression from auditory nerve fibers. PMID:22570693

  14. Motor cortex electrical stimulation augments sprouting of the corticospinal tract and promotes recovery of motor function

    PubMed Central

    Carmel, Jason B.; Martin, John H.

    2014-01-01

    The corticospinal system—with its direct spinal pathway, the corticospinal tract (CST) – is the primary system for controlling voluntary movement. Our approach to CST repair after injury in mature animals was informed by our finding that activity drives establishment of connections with spinal cord circuits during postnatal development. After incomplete injury in maturity, spared CST circuits sprout, and partially restore lost function. Our approach harnesses activity to augment this injury-dependent CST sprouting and to promote function. Lesion of the medullary pyramid unilaterally eliminates all CST axons from one hemisphere and allows examination of CST sprouting from the unaffected hemisphere. We discovered that 10 days of electrical stimulation of either the spared CST or motor cortex induces CST axon sprouting that partially reconstructs the lost CST. Stimulation also leads to sprouting of the cortical projection to the magnocellular red nucleus, where the rubrospinal tract originates. Coordinated outgrowth of the CST and cortical projections to the red nucleus could support partial re-establishment of motor systems connections to the denervated spinal motor circuits. Stimulation restores skilled motor function in our animal model. Lesioned animals have a persistent forelimb deficit contralateral to pyramidotomy in the horizontal ladder task. Rats that received motor cortex stimulation either after acute or chronic injury showed a significant functional improvement that brought error rate to pre-lesion control levels. Reversible inactivation of the stimulated motor cortex reinstated the impairment demonstrating the importance of the stimulated system to recovery. Motor cortex electrical stimulation is an effective approach to promote spouting of spared CST axons. By optimizing activity-dependent sprouting in animals, we could have an approach that can be translated to the human for evaluation with minimal delay. PMID:24994971

  15. Mesencephalic stimulation elicits inhibition of phrenic nerve activity in cat.

    PubMed Central

    Gallman, E A; Lawing, W L; Millhorn, D E

    1991-01-01

    1. Previous work from this laboratory has indicated that the mesencephalon is the anatomical substrate for a mechanism capable of inhibiting central respiratory drive in glomectomized cats for periods of up to 1 h or more following brief exposure to systemic hypoxia; phrenic nerve activity was used as an index of central respiratory drive. 2. The present study was undertaken to further localize the region responsible for the observed post-hypoxic inhibition of respiratory drive. We studied the phrenic nerve response to stimulations of the mesencephalon in anaesthetized, paralysed peripherally chemo-denervated cats with end-expired PCO2 and body temperature servo-controlled. 3. Stimulations of two types were employed. Electrical stimulation allowed rapid determination of sites from which phrenic inhibition could be elicited. Microinjections of excitatory amino acids were used subsequently in order to confine excitation to neuronal cell bodies and not axons of passage. 4. Stimulation of discrete regions of the ventromedial aspect of the mesencephalon in the vicinity of the red nucleus produced substantial inhibition of phrenic activity which lasted up to 45 min. Stimulation of other areas of the mesencephalon either produced no phrenic inhibition or resulted in a slight stimulation of phrenic activity. 5. The results are discussed in the context of the central respiratory response to hypoxia. PMID:1676420

  16. Kaon-nucleus scattering

    NASA Technical Reports Server (NTRS)

    Hong, Byungsik; Maung, Khin Maung; Wilson, John W.; Buck, Warren W.

    1989-01-01

    The derivations of the Lippmann-Schwinger equation and Watson multiple scattering are given. A simple optical potential is found to be the first term of that series. The number density distribution models of the nucleus, harmonic well, and Woods-Saxon are used without t-matrix taken from the scattering experiments. The parameterized two-body inputs, which are kaon-nucleon total cross sections, elastic slope parameters, and the ratio of the real to the imaginary part of the forward elastic scattering amplitude, are presented. The eikonal approximation was chosen as our solution method to estimate the total and absorptive cross sections for the kaon-nucleus scattering.

  17. Anatomic and physiological characteristics of the ferret lateral rectus muscle and abducens nucleus.

    PubMed

    Bishop, Keith N; McClung, J Ross; Goldberg, Stephen J; Shall, Mary S

    2007-11-01

    The ferret has become a popular model for physiological and neurodevelopmental research in the visual system. We believed it important, therefore, to study extraocular whole muscle as well as single motor unit physiology in the ferret. Using extracellular stimulation, 62 individual motor units in the ferret abducens nucleus were evaluated for their contractile characteristics. Of these motor units, 56 innervated the lateral rectus (LR) muscle alone, while 6 were split between the LR and retractor bulbi (RB) muscle slips. In addition to individual motor units, the whole LR muscle was evaluated for twitch, tetanic peak force, and fatigue. The abducens nucleus motor units showed a twitch contraction time of 15.4 ms, a mean twitch tension of 30.2 mg, and an average fusion frequency of 154 Hz. Single-unit fatigue index averaged 0.634. Whole muscle twitch contraction time was 16.7 ms with a mean twitch tension of 3.32 g. The average fatigue index of whole muscle was 0.408. The abducens nucleus was examined with horseradish peroxidase conjugated with the subunit B of cholera toxin histochemistry and found to contain an average of 183 motoneurons. Samples of LR were found to contain an average of 4,687 fibers, indicating an LR innervation ratio of 25.6:1. Compared with cat and squirrel monkeys, the ferret LR motor units contract more slowly yet more powerfully. The functional visual requirements of the ferret may explain these fundamental differences.

  18. Deep brain stimulation for the treatment of Alzheimer disease and dementias.

    PubMed

    Laxton, Adrian W; Lozano, Andres M

    2013-01-01

    To review the use of deep brain stimulation (DBS) for treatment of dementia. A PubMed literature search was conducted to identify all studies that have investigated the use of DBS for treatment of dementia. Three studies examined the use of DBS for dementia. One study involved fornix DBS for Alzheimer disease (AD), and two studies involved DBS of the nucleus basalis of Meynert, one to treat AD and one to treat Parkinson disease dementia. Evidence for the use of DBS to treat dementia is preliminary and limited. Fornix and nucleus basalis of Meynert DBS can influence activity in the pathologic neural circuits that underlie AD and Parkinson disease dementia. Further investigation into the potential clinical effects of DBS for dementia is warranted. Copyright © 2013 Elsevier Inc. All rights reserved.

  19. BDNF and AMPA receptors in the cNTS modulate the hyperglycemic reflex after local carotid body NaCN stimulation.

    PubMed

    Cuéllar, R; Montero, S; Luquín, S; García-Estrada, J; Melnikov, V; Virgen-Ortiz, A; Lemus, M; Pineda-Lemus, M; de Álvarez-Buylla, E

    2017-07-01

    The application of sodium cyanide (NaCN) to the carotid body receptors (CBR) (CBR stimulation) induces rapid blood hyperglycemia and an increase in brain glucose retention. The commissural nucleus tractus solitarius (cNTS) is an essential relay nucleus in this hyperglycemic reflex; it receives glutamatergic afferents (that also release brain derived neurotrophic factor, BDNF) from the nodose-petrosal ganglia that relays CBR information. Previous work showed that AMPA in NTS blocks hyperglycemia and brain glucose retention after CBR stimulation. In contrast, BDNF, which attenuates glutamatergic AMPA currents in NTS, enhances these glycemic responses. Here we investigated the combined effects of BDNF and AMPA (and their antagonists) in NTS on the glycemic responses to CBR stimulation. Microinjections of BDNF plus AMPA into the cNTS before CBR stimulation in anesthetized rats, induced blood hyperglycemia and an increase in brain arteriovenous (a-v) of blood glucose concentration difference, which we infer is due to increased brain glucose retention. By contrast, the microinjection of the TrkB antagonist K252a plus AMPA abolished the glycemic responses to CBR stimulation similar to what is observed after AMPA pretreatments. In BDNF plus AMPA microinjections preceding CBR stimulation, the number of c-fos immunoreactive cNTS neurons increased. In contrast, in the rats microinjected with K252a plus AMPA in NTS, before CBR stimulation, c-fos expression in cNTS decreased. The expression of AMPA receptors GluR2/3 did not change in any of the studied groups. These results indicate that BDNF in cNTS plays a key role in the modulation of the hyperglycemic reflex initiated by CBR stimulation. Copyright © 2017. Published by Elsevier B.V.

  20. Role of Reuniens Nucleus Projections to the Medial Prefrontal Cortex and to the Hippocampal Pyramidal CA1 Area in Associative Learning

    PubMed Central

    Eleore, Lyndell; López-Ramos, Juan Carlos; Guerra-Narbona, Rafael; Delgado-García, José M.

    2011-01-01

    We studied the interactions between short- and long-term plastic changes taking place during the acquisition of a classical eyeblink conditioning and following high-frequency stimulation (HFS) of the reuniens nucleus in behaving mice. Synaptic changes in strength were studied at the reuniens-medial prefrontal cortex (mPFC) and the reuniens-CA1 synapses. Input/output curves and a paired-pulse study enabled determining the functional capabilities of the two synapses and the optimal intensities to be applied at the reuniens nucleus during classical eyeblink conditioning and for HFS applied to the reuniens nucleus. Animals were conditioned using a trace paradigm, with a tone as conditioned stimulus (CS) and an electric shock to the trigeminal nerve as unconditioned stimulus (US). A single pulse was presented to the reuniens nucleus to evoke field EPSPs (fEPSPs) in mPFC and CA1 areas during the CS-US interval. No significant changes in synaptic strength were observed at the reuniens-mPFC and reuniens-CA1 synapses during the acquisition of eyelid conditioned responses (CRs). Two successive HFS sessions carried out during the first two conditioning days decreased the percentage of CRs, without evoking any long-term potentiation (LTP) at the recording sites. HFS of the reuniens nucleus also prevented the proper acquisition of an object discrimination task. A subsequent study revealed that HFS of the reuniens nucleus evoked a significant decrease of paired-pulse facilitation. In conclusion, reuniens nucleus projections to prefrontal and hippocampal circuits seem to participate in the acquisition of associative learning through a mechanism that does not required the development of LTP. PMID:21858159

  1. Processing of emotional information in the human subthalamic nucleus.

    PubMed

    Buot, Anne; Welter, Marie-Laure; Karachi, Carine; Pochon, Jean-Baptiste; Bardinet, Eric; Yelnik, Jérôme; Mallet, Luc

    2013-12-01

    The subthalamic nucleus (STN) is an efficient target for treating patients with Parkinson's disease as well as patients with obsessive-compulsive disorder (OCD) using high frequency stimulation (HFS). In both Parkinson's disease and OCD patients, STN-HFS can trigger abnormal behaviours, such as hypomania and impulsivity. To investigate if this structure processes emotional information, and whether it depends on motor demands, we recorded subthalamic local field potentials in 16 patients with Parkinson's disease using deep brain stimulation electrodes. Recordings were made with and without dopaminergic treatment while patients performed an emotional categorisation paradigm in which the response varied according to stimulus valence (pleasant, unpleasant and neutral) and to the instruction given (motor, non-motor and passive). Pleasant, unpleasant and neutral stimuli evoked an event related potential (ERP). Without dopamine medication, ERP amplitudes were significantly larger for unpleasant compared with neutral pictures, whatever the response triggered by the stimuli; and the magnitude of this effect was maximal in the ventral part of the STN. No significant difference in ERP amplitude was observed for pleasant pictures. With dopamine medication, ERP amplitudes were significantly increased for pleasant compared with neutral pictures whatever the response triggered by the stimuli, while ERP amplitudes to unpleasant pictures were not modified. These results demonstrate that the ventral part of the STN processes the emotional valence of stimuli independently of the motor context and that dopamine enhances processing of pleasant information. These findings confirm the specific involvement of the STN in emotional processes in human, which may underlie the behavioural changes observed in patients with deep brain stimulation.

  2. Differential inputs to striatal cholinergic and parvalbumin interneurons imply functional distinctions

    PubMed Central

    Klug, Jason R; Engelhardt, Max D; Cadman, Cara N; Li, Hao; Smith, Jared B; Ayala, Sarah; Williams, Elora W; Hoffman, Hilary

    2018-01-01

    Striatal cholinergic (ChAT) and parvalbumin (PV) interneurons exert powerful influences on striatal function in health and disease, yet little is known about the organization of their inputs. Here using rabies tracing, electrophysiology and genetic tools, we compare the whole-brain inputs to these two types of striatal interneurons and dissect their functional connectivity in mice. ChAT interneurons receive a substantial cortical input from associative regions of cortex, such as the orbitofrontal cortex. Amongst subcortical inputs, a previously unknown inhibitory thalamic reticular nucleus input to striatal PV interneurons is identified. Additionally, the external segment of the globus pallidus targets striatal ChAT interneurons, which is sufficient to inhibit tonic ChAT interneuron firing. Finally, we describe a novel excitatory pathway from the pedunculopontine nucleus that innervates ChAT interneurons. These results establish the brain-wide direct inputs of two major types of striatal interneurons and allude to distinct roles in regulating striatal activity and controlling behavior. PMID:29714166

  3. Electromagnetic processes in nucleus-nucleus collisions relating to space radiation research

    NASA Technical Reports Server (NTRS)

    Norbury, John W.

    1992-01-01

    Most of the papers within this report deal with electromagnetic processes in nucleus-nucleus collisions which are of concern in the space radiation program. In particular, the removal of one and two nucleons via both electromagnetic and strong interaction processes has been extensively investigated. The theory of relativistic Coulomb fission has also been developed. Several papers on quark models also appear. Finally, note that the theoretical methods developed in this work have been directly applied to the task of radiation protection of astronauts. This has been done by parameterizing the theoretical formalism in such a fashion that it can be used in cosmic ray transport codes.

  4. Deep brain stimulation during early adolescence prevents microglial alterations in a model of maternal immune activation.

    PubMed

    Hadar, Ravit; Dong, Le; Del-Valle-Anton, Lucia; Guneykaya, Dilansu; Voget, Mareike; Edemann-Callesen, Henriette; Schweibold, Regina; Djodari-Irani, Anais; Goetz, Thomas; Ewing, Samuel; Kettenmann, Helmut; Wolf, Susanne A; Winter, Christine

    2017-07-01

    In recent years schizophrenia has been recognized as a neurodevelopmental disorder likely involving a perinatal insult progressively affecting brain development. The poly I:C maternal immune activation (MIA) rodent model is considered as a neurodevelopmental model of schizophrenia. Using this model we and others demonstrated the association between neuroinflammation in the form of altered microglia and a schizophrenia-like endophenotype. Therapeutic intervention using the anti-inflammatory drug minocycline affected altered microglia activation and was successful in the adult offspring. However, less is known about the effect of preventive therapeutic strategies on microglia properties. Previously we found that deep brain stimulation of the medial prefrontal cortex applied pre-symptomatically to adolescence MIA rats prevented the manifestation of behavioral and structural deficits in adult rats. We here studied the effects of deep brain stimulation during adolescence on microglia properties in adulthood. We found that in the hippocampus and nucleus accumbens, but not in the medial prefrontal cortex, microglial density and soma size were increased in MIA rats. Pro-inflammatory cytokine mRNA was unchanged in all brain areas before and after implantation and stimulation. Stimulation of either the medial prefrontal cortex or the nucleus accumbens normalized microglia density and soma size in main projection areas including the hippocampus and in the area around the electrode implantation. We conclude that in parallel to an alleviation of the symptoms in the rat MIA model, deep brain stimulation has the potential to prevent the neuroinflammatory component in this disease. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Is {sup 276}U a doubly magic nucleus?

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liliani, N., E-mail: netta.liliani@gmail.com; Sulaksono, A.

    2016-04-19

    We investigate a possible new doubly magic heavy nucleus by using a relativistic mean-field (RMF) model with the addition of a cross interaction term of omega-rho mesons and an electromagnetic exchange term. We propose that {sup 276}U is a doubly magic nucleus. The evidence for {sup 276}U being a doubly magic nucleus is shown through the two-nucleon gaps, the single-particle energies, and the neutron skin thickness of the nucleus. We have also found that the prediction of {sup 276}U as a doubly magic nucleus by the RMF model is not affected by the inclusion of isoscalar-isovector and electromagnetic exchange couplings.

  6. [Abscess at the implant site following apical parodontitis. Hardware-related complications of deep brain stimulation].

    PubMed

    Sixel-Döring, F; Trenkwalder, C; Kappus, C; Hellwig, D

    2006-08-01

    Deep brain stimulation of the subthalamic nucleus is an important treatment option for advanced stages of idiopathic Parkinson's disease, leading to significant improvement of motor symptoms in suited patients. Hardware-related complications such as technical malfunction, skin erosion, and infections however cause patient discomfort and additional expense. The patient presented here suffered a putrid infection of the impulse generator site following only local dental treatment of apical parodontitis. Therefore, prophylactic systemic antibiotic treatment is recommended for patients with implanted deep brain stimulation devices in case of operations, dental procedures, or infectious disease.

  7. Treating post-traumatic tremor with deep brain stimulation: report of five cases.

    PubMed

    Issar, Neil M; Hedera, Peter; Phibbs, Fenna T; Konrad, Peter E; Neimat, Joseph S

    2013-12-01

    Post-traumatic tremor is one of the most common movement disorders resulting from severe head trauma. However, literature regarding successful deep brain stimulation (DBS) treatment is scarce, resulting in ambiguity regarding the optimal lead location. Most cases support the ventral intermediate nucleus, but there is evidence to defend DBS of the zona incerta, ventral oralis anterior/posterior, and/or a combination of these targets. We report five patients with disabling post-traumatic tremor treated with DBS of the ventral intermediate nucleus and of the globus pallidus internus. Patients were referred to the Vanderbilt Movement Disorders Division, and surgical intervention was determined by a DBS Multidisciplinary Committee. Standard DBS procedure was followed. Patients 1-4 sustained severe diffuse axonal injuries. Patients 1-3 underwent unilateral ventral intermediate nucleus DBS for contralateral tremor, while Patient 4 underwent bilateral ventral intermediate nucleus DBS. Patients 1-3 experienced good tremor reduction, while Patient 4 experienced moderate tremor reduction with some dystonic posturing of the hands. Patient 5 had dystonic posturing of the right upper extremity with tremor of the left upper extremity. He was treated with bilateral DBS of the globus pallidus internus and showed good tremor reduction at follow-up. Unilateral or bilateral DBS of the ventral intermediate nucleus and bilateral DBS of the globus pallidus internus may be effective and safe treatment modalities for intractable post-traumatic tremor. Further studies are needed to clarify the optimal target for surgical treatment of post-traumatic tremor. Published by Elsevier Ltd.

  8. Observation of direct hadronic pairs in nucleus-nucleus collisions in JACEE emulsion chambers

    NASA Technical Reports Server (NTRS)

    Burnett, T. H.; Dake, S.; Fuki, M.; Gregory, J. C.; Hayashi, T.; Hayashi, T.; Holynski, R.; Iwai, J.; Jones, W. V.; Jurak, A.

    1985-01-01

    In a number of high energy ( or = 1 TeV/amu) nucleus-nucleus collisions observed in Japanese-American Cooperative Emulsion Experiment (JACEE) emulsion chambers, nonrandom spatial association of produced charged particles, mostly hadronic pairs, are observed. Similar narrow pairs are observed in about 100 events at much low energy (20 to 60 GeV/amu). Analysis shows that 30 to 50% of Pair abundances are understood by the Hambury-Brown-Twiss effect, and the remainder seems to require other explanations.

  9. Serotonergic antidepressants decrease hedonic signals but leave learning signals in the nucleus accumbens unaffected.

    PubMed

    Graf, Heiko; Metzger, Coraline D; Walter, Martin; Abler, Birgit

    2016-01-06

    Investigating the effects of serotonergic antidepressants on neural correlates of visual erotic stimulation revealed decreased reactivity within the dopaminergic reward network along with decreased subjective sexual functioning compared with placebo. However, a global dampening of the reward system under serotonergic drugs is not intuitive considering clinical observations of their beneficial effects in the treatment of depression. Particularly, learning signals as coded in prediction error processing within the dopaminergic reward system can be assumed to be rather enhanced as antidepressant drugs have been demonstrated to facilitate the efficacy of psychotherapeutic interventions relying on learning processes. Within the same study sample, we now explored the effects of serotonergic and dopaminergic/noradrenergic antidepressants on prediction error signals compared with placebo by functional MRI. A total of 17 healthy male participants (mean age: 25.4 years) were investigated under the administration of paroxetine, bupropion and placebo for 7 days each within a randomized, double-blind, within-subject cross-over design. During functional MRI, we used an established monetary incentive task to explore neural prediction error signals within the bilateral nucleus accumbens as region of interest within the dopaminergic reward system. In contrast to diminished neural activations and subjective sexual functioning under the serotonergic agent paroxetine under visual erotic stimulation, we revealed unaffected or even enhanced neural prediction error processing within the nucleus accumbens under this antidepressant along with unaffected behavioural processing. Our study provides evidence that serotonergic antidepressants facilitate prediction error signalling and may support suggestions of beneficial effects of these agents on reinforced learning as an essential element in behavioural psychotherapy.

  10. INTRINSIC NEURONAL PLASTICITY IN THE JUXTACAPSULAR NUCLEUS OF THE BED NUCLEI OF THE STRIA TERMINALIS (jcBNST)

    PubMed Central

    Francesconi, Walter; Berton, Fulvia; Koob, George F.; Sanna, Pietro Paolo

    2010-01-01

    The juxtacapsular nucleus of the anterior division of the BNST (jcBNST) receives robust glutamatergic projections from the basolateral nucleus of the amygdala (BLA), the postpiriform transition area, and the insular cortex as well as dopamine (DA) inputs from the midbrain. In turn the jcBNST sends GABAergic projections to the medial division of the central nucleus of the amygdala (CEAm) as well as other brain regions. We recently described a form of long-term potentiation of the intrinsic excitability (LTP-IE) of neurons of the juxtacapsular nucleus of BNST (jcBNST) in response to high-frequency stimulation (HFS) of the stria terminalis that was impaired during protracted withdrawal from alcohol, cocaine, and heroin and in rats chronically treated with corticotropin releasing factor (CRF) intracerebroventricularly. Here we show that DAergic neurotransmission is required for the induction of LTP-IE of jcBNTS neurons through dopamine (DA) D1 receptors. Thus, activation of the central CRF stress system and altered DAergic neurotransmission during protracted withdrawal from alcohol and drugs of abuse may contribute to the disruption of LTP-IE in the jcBNST. Impairment of this form of intrinsic neuronal plasticity in the jcBNST could result in inadequate neuronal integration and reduced inhibition of the CEA, contributing to the negative affective state that characterizes protracted abstinence in post-dependent individuals. These results provide a novel neurobiological target for vulnerability to alcohol and drug dependence. PMID:19683025

  11. Subthalamic nucleus gamma activity increases not only during movement but also during movement inhibition

    PubMed Central

    Fischer, Petra; Pogosyan, Alek; Herz, Damian M; Cheeran, Binith; Green, Alexander L; Fitzgerald, James; Aziz, Tipu Z; Hyam, Jonathan; Little, Simon; Foltynie, Thomas; Limousin, Patricia; Zrinzo, Ludvic; Brown, Peter; Tan, Huiling

    2017-01-01

    Gamma activity in the subthalamic nucleus (STN) is widely viewed as a pro-kinetic rhythm. Here we test the hypothesis that rather than being specifically linked to movement execution, gamma activity reflects dynamic processing in this nucleus. We investigated the role of gamma during fast stopping and recorded scalp electroencephalogram and local field potentials from deep brain stimulation electrodes in 9 Parkinson’s disease patients. Patients interrupted finger tapping (paced by a metronome) in response to a stop-signal sound, which was timed such that successful stopping would occur only in ~50% of all trials. STN gamma (60–90 Hz) increased most strongly when the tap was successfully stopped, whereas phase-based connectivity between the contralateral STN and motor cortex decreased. Beta or theta power seemed less directly related to stopping. In summary, STN gamma activity may support flexible motor control as it did not only increase during movement execution but also during rapid action-stopping. DOI: http://dx.doi.org/10.7554/eLife.23947.001 PMID:28742498

  12. Analysis of relativistic nucleus-nucleus interactions in emulsion chambers

    NASA Technical Reports Server (NTRS)

    Mcguire, Stephen C.

    1987-01-01

    The development of a computer-assisted method is reported for the determination of the angular distribution data for secondary particles produced in relativistic nucleus-nucleus collisions in emulsions. The method is applied to emulsion detectors that were placed in a constant, uniform magnetic field and exposed to beams of 60 and 200 GeV/nucleon O-16 ions at the Super Proton Synchrotron (SPS) of the European Center for Nuclear Research (CERN). Linear regression analysis is used to determine the azimuthal and polar emission angles from measured track coordinate data. The software, written in BASIC, is designed to be machine independent, and adaptable to an automated system for acquiring the track coordinates. The fitting algorithm is deterministic, and takes into account the experimental uncertainty in the measured points. Further, a procedure for using the track data to estimate the linear momenta of the charged particles observed in the detectors is included.

  13. Microtubules move the nucleus to quiescence.

    PubMed

    Laporte, Damien; Sagot, Isabelle

    2014-01-01

    The nucleus is a cellular compartment that hosts several macro-molecular machines displaying a highly complex spatial organization. This tight architectural orchestration determines not only DNA replication and repair but also regulates gene expression. In budding yeast microtubules play a key role in structuring the nucleus since they condition the Rabl arrangement in G1 and chromosome partitioning during mitosis through their attachment to centromeres via the kinetochore proteins. Recently, we have shown that upon quiescence entry, intranuclear microtubules emanating from the spindle pole body elongate to form a highly stable bundle that spans the entire nucleus. Here, we examine some molecular mechanisms that may underlie the formation of this structure. As the intranuclear microtubule bundle causes a profound re-organization of the yeast nucleus and is required for cell survival during quiescence, we discuss the possibility that the assembly of such a structure participates in quiescence establishment.

  14. Stopping powers and cross sections due to two-photon processes in relativistic nucleus-nucleus collisions

    NASA Technical Reports Server (NTRS)

    Cheung, Wang K.; Norbury, John W.

    1994-01-01

    The effects of electromagnetic-production processes due to two-photon exchange in nucleus-nucleus collisions are discussed. Feynman diagrams for two-photon exchange are evaluated using quantum electrodynamics. The total cross section and stopping power for projectile and target nuclei of identical charge are found to be significant for heavy nuclei above a few GeV per nucleon-incident energy.

  15. Role of Arcuate Nucleus in the Regulation of Feeding Behavior in the Process of Altitude Acclimatization in Rats.

    PubMed

    Liu, Xiang-Wen; Yin, Jie; Ma, Qi-Sheng; Qi, Chu-Chu; Mu, Ji-Ying; Zhang, Lang; Gao, Li-Ping; Jing, Yu-Hong

    2017-09-01

    Liu, Xiang-Wen, Jie Yin, Qi-Sheng Ma, Chu-Chu Qi, Ji-Ying Mu, Lang Zhang, Li-Ping Gao, and Yu-Hong Jing. Role of arcuate nucleus in the regulation of feeding behavior in the process of altitude acclimatization in rats. High Alt Med Biol. 18:234-241, 2017.-Highly efficient energy utilization and metabolic homeostasis maintenance rely on neuromodulation. Altitude exposure is known to stimulate neuroendocrine systems to respond to acute hypoxia and adaptive acclimatization. However, limited data on how the adaptive regulation of the arcuate nucleus performs in the process of altitude acclimatization are available. In the present study, male Sprague Dawley rats were transported to Huashixia, Qinghai (with an altitude of 4400 m) from Xian (with an altitude of 300 m) by air; rats were consistently raised in Xian as control. Food uptake and body weight were measured consecutively after being subjected to high-altitude condition. Contents of plasma leptin and ghrelin were analyzed by the Enzyme Linked Immunosorbent Assay (ELISA) Kits. Brain coronal sections were obtained, and neuropeptide Y (NPY), proopiomelanocotin (POMC), and c-fos immunoreactivity in arcuate nucleus were observed. Arcuate nucleus was isolated from the hypothalamus, and the mRNA of NPY and POMC were measured by quantitative real-time polymerase chain reaction. Our results showed both food consumption and body weight decreased in the high plateau compared with rats raised in the low-altitude condition. Plasma leptin increased at the early stage, and ghrelin decreased at a later stage after reaching the high plateau. The peak of c-fos immunoreactivity in the arcuate nucleus was at day 3 after reaching the high plateau. The expression level of NPY increased, and POMC decreased in the arcuate nucleus at day 7 after reaching the high plateau compared with the plain control group. These results indicate that the arcuate nucleus of hypothalamus performs an important function in regulating feeding behavior

  16. Contralateral Effects and Binaural Interactions in Dorsal Cochlear Nucleus

    PubMed Central

    2005-01-01

    The dorsal cochlear nucleus (DCN) receives afferent input from the auditory nerve and is thus usually thought of as a monaural nucleus, but it also receives inputs from the contralateral cochlear nucleus as well as descending projections from binaural nuclei. Evidence suggests that some of these commissural and efferent projections are excitatory, whereas others are inhibitory. The goals of this study were to investigate the nature and effects of these inputs in the DCN by measuring DCN principal cell (type IV unit) responses to a variety of contralateral monaural and binaural stimuli. As expected, the results of contralateral stimulation demonstrate a mixture of excitatory and inhibitory influences, although inhibitory effects predominate. Most type IV units are weakly, if at all, inhibited by tones but are strongly inhibited by broadband noise (BBN). The inhibition evoked by BBN is also low threshold and short latency. This inhibition is abolished and excitation is revealed when strychnine, a glycine-receptor antagonist, is applied to the DCN; application of bicuculline, a GABAA-receptor antagonist, has similar effects but does not block the onset of inhibition. Manipulations of discrete fiber bundles suggest that the inhibitory, but not excitatory, inputs to DCN principal cells enter the DCN via its output pathway, and that the short latency inhibition is carried by commissural axons. Consistent with their respective monaural effects, responses to binaural tones as a function of interaural level difference are essentially the same as responses to ipsilateral tones, whereas binaural BBN responses decrease with increasing contralateral level. In comparison to monaural responses, binaural responses to virtual space stimuli show enhanced sensitivity to the elevation of a sound source in ipsilateral space but reduced sensitivity in contralateral space. These results show that the contralateral inputs to the DCN are functionally relevant in natural listening

  17. Formation, structure, and evolution of boiling nucleus and interfacial tension between bulk liquid phase and nucleus

    NASA Astrophysics Data System (ADS)

    Wang, Xiao-Dong; Peng, Xiao-Feng; Tian, Yong; Wang, Bu-Xuan

    2005-05-01

    In this paper, the concept of the molecular free path is introduced to derive a criterion distinguishing active molecules from inactive molecules in liquid phase. A concept of the critical aggregation concentration (CAC) of active molecules is proposed to describe the physical configuration before the formation of a nucleus during vapor-liquid phase transition. All active molecules exist as monomers when the concentration of active molecules is lower than CAC, while the active molecules will generate aggregation once the concentration of the active molecules reaches CAC. However, these aggregates with aggregation number, N, smaller than five can steadily exist in bulk phase. The other excess active molecules can only produce infinite aggregation and form a critical nucleus of vapor-liquid phase transition. Without any outer perturbation the state point of CAC corresponds to the critical superheated or supercooled state. Meanwhile, a model of two-region structure of a nucleus is proposed to describe nucleus evolution. The interfacial tension between bulk liquid phase and nucleus is dependent of the density gradient in the transition region and varies with the structure change of the transition region. With the interfacial tension calculated using this model, the predicted nucleation rate is very close to the experimental measurement. Furthermore, this model and associated analysis provides solid theoretical evidences to clarify the definition of nucleation rate and understand nucleation phenomenon with the insight into the physical nature.

  18. REM Sleep at its Core – Circuits, Neurotransmitters, and Pathophysiology

    PubMed Central

    Fraigne, Jimmy J.; Torontali, Zoltan A.; Snow, Matthew B.; Peever, John H.

    2015-01-01

    Rapid eye movement (REM) sleep is generated and maintained by the interaction of a variety of neurotransmitter systems in the brainstem, forebrain, and hypothalamus. Within these circuits lies a core region that is active during REM sleep, known as the subcoeruleus nucleus (SubC) or sublaterodorsal nucleus. It is hypothesized that glutamatergic SubC neurons regulate REM sleep and its defining features such as muscle paralysis and cortical activation. REM sleep paralysis is initiated when glutamatergic SubC cells activate neurons in the ventral medial medulla, which causes release of GABA and glycine onto skeletal motoneurons. REM sleep timing is controlled by activity of GABAergic neurons in the ventrolateral periaqueductal gray and dorsal paragigantocellular reticular nucleus as well as melanin-concentrating hormone neurons in the hypothalamus and cholinergic cells in the laterodorsal and pedunculo-pontine tegmentum in the brainstem. Determining how these circuits interact with the SubC is important because breakdown in their communication is hypothesized to underlie narcolepsy/cataplexy and REM sleep behavior disorder (RBD). This review synthesizes our current understanding of mechanisms generating healthy REM sleep and how dysfunction of these circuits contributes to common REM sleep disorders such as cataplexy/narcolepsy and RBD. PMID:26074874

  19. The mediodorsal thalamic nucleus and schizophrenia

    PubMed Central

    Alelú-Paz, Raúl; Giménez-Amaya, José Manuel

    2008-01-01

    The mediodorsal nucleus of the human thalamus is in a crucial position that allows it to establish connections with diverse cerebral structures, particularly the prefrontal cortex. The present review examines existing neurobiologic studies of the brains of people with and without schizophrenia that indicate a possible involvement of the mediodorsal nucleus in this psychiatric disorder. Studies at synaptic and cellular levels of the neurobiology of the mediodorsal nucleus, together with a better anatomic understanding of this diencephalic structure owing to neuroimaging studies, should help to establish a more deep and solid pathophysiologic model of schizophrenia. PMID:18982171

  20. Noise over-exposure alters long-term somatosensory-auditory processing in the dorsal cochlear nucleus – possible basis for tinnitus-related hyperactivity?

    PubMed Central

    Dehmel, Susanne; Pradhan, Shashwati; Koehler, Seth; Bledsoe, Sanford; Shore, Susan

    2012-01-01

    The dorsal cochlear nucleus (DCN) is the first neural site of bimodal auditory-somatosensory integration. Previous studies have shown that stimulation of somatosensory pathways results in immediate suppression or enhancement of subsequent acoustically-evoked discharges. In the unimpaired auditory system suppression predominates. However, damage to the auditory input pathway leads to enhancement of excitatory somatosensory inputs to the cochlear nucleus, changing their effects on DCN neurons (Zeng et al., 2009; Shore et al., 2008). Given the well described connection between the somatosensory system and tinnitus in patients we sought to determine if plastic changes in long lasting bimodal somatosensory-auditory processing accompany tinnitus. Here we demonstrate for the first time in vivo long-term effects of somatosensory inputs on acoustically-evoked discharges of DCN neurons in guinea pigs. The effects of trigeminal nucleus stimulation are compared between normal-hearing animals and animals overexposed with narrow band noise and behaviorally tested for tinnitus. The noise exposure resulted in a temporary threshold shift (TTS) in auditory brainstem responses but a persistent increase in spontaneous and sound-evoked DCN unit firing rates and increased steepness of rate-level functions (RLFs). Rate increases were especially prominent in buildup units. The long-term somatosensory enhancement of sound-evoked responses was strengthened while suppressive effects diminished in noise-exposed animals, especially those that developed tinnitus. Damage to the auditory nerve (ANF) is postulated to trigger compensatory long-term synaptic plasticity of somatosensory inputs that might be an important underlying mechanism for tinnitus generation. PMID:22302808

  1. The nucleus of the optic tract (NOT) and the dorsal terminal nucleus (DTN) of opossums (Didelphis marsupialis aurita).

    PubMed

    Vargas, C D; Volchan, E; Nasi, J P; Bernardes, R F; Rocha-Miranda, C E

    1996-01-01

    Wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP) was injected unilaterally into the pretectocollicular region of opossums (Didelphis marsupialis aurita), primarily to investigate the existence of a commissural subcortical pathway but also to reveal afferents and efferents of the nucleus of the optic tract (NOT) and dorsal terminal nucleus (DTN) in this species. Labelled cells and terminals were observed in the contralateral NOT-DTN. Furthermore, HRP was injected bilaterally in the region of the inferior olive (IO) to verify if the distribution of labelled cells in the NOT-DTN overlapped the region of commissural labelled cells. The two subpopulations of retrogradely labelled cells coincided, being distributed within the retinal terminal field attributed to the NOT-DTN, as revealed by contralateral eye injections of HRP. The commissural cells were located slightly more ventral than the olivary cells in the optic tract. The pretectocollicular WGA-HRP injections also labelled cells and terminals bilaterally in the lateral terminal nucleus (LTN), interstitial nucleus of the superior fasciculus, posterior fibers (INSFp), ventral lateral geniculate nucleus (vLGN), and superior colliculus (SC) and ipsilaterally in the medial terminal nucleus (MTN). In addition, further caudally, labelled cells and terminals were observed bilaterally in the nuclei prepositus hypoglossi (PH) and in the medial (MVN) and lateral (LVN) vestibular nuclei. Labelled terminals were found in the ipsilateral nucleus reticularis tegmenti pontis (NRTP) and in the IO with ipsilateral predominance. This study allowed an anatomical delimitation of the NOT-DTN in this opossum species, as defined by the olivary and commissural subpopulations, as well as a hodological evaluation of this region. The existence of some common anatomical aspects with other mammalian species is discussed.

  2. Effects of stimulation configurations on place pitch discrimination in cochlear implants.

    PubMed

    Kwon, Bomjun J; Perry, Trevor T; Olmstead, Vauna L

    2011-06-01

    The present study aimed to examine the effect of electrode configuration, specifically monopolar (MP) or bipolar (BP) stimulation, on place pitch discrimination in cochlear implants (CIs). Twelve subjects implanted with the Nucleus Freedom device were presented with various pairs of stimulation across the electrode array, with varying degrees of distance between stimulation sites, and asked to judge the higher of the two in pitch. Each pair was presented either in the same mode or in different modes of stimulation for the within-mode or across-mode condition, respectively, at least 20 times. The result of the within-mode condition revealed that subjects, on average, were able to discriminate pitches significantly better in MP than in BP, with the sensitivity index (d') for adjacent channels of 1.2 for MP and 0.8 for BP. The result of the across-mode condition revealed that while individual variability existed, there was a strong tendency for CI subjects to perceive a higher pitch in BP stimulation than in MP for a similar site of stimulation. In other words, an MP channel needed to be shifted in a basal direction by as much as two electrodes on average to elicit a pitch comparable to that of a BP channel. © 2011 Acoustical Society of America

  3. Deep brain stimulation mechanisms: beyond the concept of local functional inhibition.

    PubMed

    Deniau, Jean-Michel; Degos, Bertrand; Bosch, Clémentine; Maurice, Nicolas

    2010-10-01

    Deep brain electrical stimulation has become a recognized therapy in the treatment of a variety of motor disorders and has potentially promising applications in a wide range of neurological diseases including neuropsychiatry. Behavioural observation that electrical high-frequency stimulation of a given brain area induces an effect similar to a lesion suggested a mechanism of functional inhibition. In vitro and in vivo experiments as well as per operative recordings in patients have revealed a variety of effects involving local changes of neuronal excitability as well as widespread effects throughout the connected network resulting from activation of axons, including antidromic activation. Here we review current data regarding the local and network activity changes induced by high-frequency stimulation of the subthalamic nucleus and discuss this in the context of motor restoration in Parkinson's disease. Stressing the important functional consequences of axonal activation in deep brain stimulation mechanisms, we highlight the importance of developing anatomical knowledge concerning the fibre connections of the putative therapeutic targets. © 2010 The Authors. European Journal of Neuroscience © 2010 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.

  4. Azimuthal correlation and collective behavior in nucleus-nucleus collisions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mali, P.; Mukhopadhyay, A., E-mail: amitabha-62@rediffmail.com; Sarkar, S.

    2015-03-15

    Various flow effects of nuclear and hadronic origin are investigated in nucleus-nucleus collisions. Nuclear emulsion data collected from {sup 84}Kr + Ag/Br interaction at an incident energy of 1.52 GeV per nucleon and from {sup 28}Si + Ag/Br interaction at an incident energy of 14.5 GeV per nucleon are used in the investigation. The transverse momentum distribution and the flow angle analysis show that collective behavior, like a bounce-off effect of the projectile spectators and a sidesplash effect of the target spectators, are present in our event samples. From an azimuthal angle analysis of the data we also see amore » direct flow of the projectile fragments and of the produced charged particles. On the other hand, for both data samples the target fragments exhibit a reverse flow, while the projectile fragments exhibit an elliptic flow. Relevant flow parameters are measured.« less

  5. The angiotensin II-AT1 receptor stimulates reactive oxygen species within the cell nucleus

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pendergrass, Karl D.; Gwathmey, TanYa M.; Michalek, Ryan D.

    2009-06-26

    We and others have reported significant expression of the Ang II Type 1 receptor (AT1R) on renal nuclei; thus, the present study assessed the functional pathways and distribution of the intracellular AT1R on isolated nuclei. Ang II (1 nM) stimulated DCF fluorescence, an intranuclear indicator of reactive oxygen species (ROS), while the AT1R antagonist losartan or the NADPH oxidase (NOX) inhibitor DPI abolished the increase in ROS. Dual labeling of nuclei with antibodies against nucleoporin 62 (Nup62) and AT1R or the NADPH oxidase isoform NOX4 revealed complete overlap of the Nup62 and AT1R (99%) by flow cytometry, while NOX4 wasmore » present on 65% of nuclei. Treatment of nuclei with a PKC agonist increased ROS while the PKC inhibitor GF109203X or PI3 kinase inhibitor LY294002 abolished Ang II stimulation of ROS. We conclude that the Ang II-AT1R-PKC axis may directly influence nuclear function within the kidney through a redox sensitive pathway.« less

  6. Subthalamic stimulation modulates cortical motor network activity and synchronization in Parkinson’s disease

    PubMed Central

    Klotz, Rosa; Govindan, Rathinaswamy B.; Scholten, Marlieke; Naros, Georgios; Ramos-Murguialday, Ander; Bunjes, Friedemann; Meisner, Christoph; Plewnia, Christian; Krüger, Rejko

    2015-01-01

    Dynamic modulations of large-scale network activity and synchronization are inherent to a broad spectrum of cognitive processes and are disturbed in neuropsychiatric conditions including Parkinson’s disease. Here, we set out to address the motor network activity and synchronization in Parkinson’s disease and its modulation with subthalamic stimulation. To this end, 20 patients with idiopathic Parkinson’s disease with subthalamic nucleus stimulation were analysed on externally cued right hand finger movements with 1.5-s interstimulus interval. Simultaneous recordings were obtained from electromyography on antagonistic muscles (right flexor digitorum and extensor digitorum) together with 64-channel electroencephalography. Time-frequency event-related spectral perturbations were assessed to determine cortical and muscular activity. Next, cross-spectra in the time-frequency domain were analysed to explore the cortico-cortical synchronization. The time-frequency modulations enabled us to select a time-frequency range relevant for motor processing. On these time-frequency windows, we developed an extension of the phase synchronization index to quantify the global cortico-cortical synchronization and to obtain topographic differentiations of distinct electrode sites with respect to their contributions to the global phase synchronization index. The spectral measures were used to predict clinical and reaction time outcome using regression analysis. We found that movement-related desynchronization of cortical activity in the upper alpha and beta range was significantly facilitated with ‘stimulation on’ compared to ‘stimulation off’ on electrodes over the bilateral parietal, sensorimotor, premotor, supplementary-motor, and prefrontal areas, including the bilateral inferior prefrontal areas. These spectral modulations enabled us to predict both clinical and reaction time improvement from subthalamic stimulation. With ‘stimulation on’, interhemispheric cortico

  7. Fluctuation analysis of relativistic nucleus-nucleus collisions in emulsion chambers

    NASA Technical Reports Server (NTRS)

    Mcguire, Stephen C.

    1988-01-01

    An analytical technique was developed for identifying enhanced fluctuations in the angular distributions of secondary particles produced from relativistic nucleus-nucleus collisions. The method is applied under the assumption that the masses of the produced particles are small compared to their linear momenta. The importance of particles rests in the fact that enhanced fluctuations in the rapidity distributions is considered to be an experimental signal for the creation of the quark-gluon-plasma (QGP), a state of nuclear matter predicted from the quantum chromodynamics theory (QCD). In the approach, Monte Carlo simulations are employed that make use of a portable random member generator that allow the calculations to be performed on a desk-top computer. The method is illustrated with data taken from high altitude emulsion exposures and is immediately applicable to similar data from accelerator-based emulsion exposures.

  8. Modulation of Neurally Mediated Vasodepression and Bradycardia by Electroacupuncture through Opioids in Nucleus Tractus Solitarius.

    PubMed

    Tjen-A-Looi, Stephanie C; Fu, Liang-Wu; Guo, Zhi-Ling; Longhurst, John C

    2018-01-30

    Stimulation of vagal afferent endings with intravenous phenylbiguanide (PBG) causes both bradycardia and vasodepression, simulating neurally mediated syncope. Activation of µ-opioid receptors in the nucleus tractus solitarius (NTS) increases blood pressure. Electroacupuncture (EA) stimulation of somatosensory nerves underneath acupoints P5-6, ST36-37, LI6-7 or G37-39 selectively but differentially modulates sympathoexcitatory responses. We therefore hypothesized that EA-stimulation at P5-6 or ST36-37, but not LI6-7 or G37-39 acupoints, inhibits the bradycardia and vasodepression through a µ-opioid receptor mechanism in the NTS. We observed that stimulation at acupoints P5-6 and ST36-37 overlying the deep somatosensory nerves and LI6-7 and G37-39 overlying cutaneous nerves differentially evoked NTS neural activity in anesthetized and ventilated animals. Thirty-min of EA-stimulation at P5-6 or ST36-37 reduced the depressor and bradycardia responses to PBG while EA at LI6-7 or G37-39 did not. Congruent with the hemodynamic responses, EA at P5-6 and ST36-37, but not at LI6-7 and G37-39, reduced vagally evoked activity of cardiovascular NTS cells. Finally, opioid receptor blockade in the NTS with naloxone or a specific μ-receptor antagonist reversed P5-6 EA-inhibition of the depressor, bradycardia and vagally evoked NTS activity. These data suggest that point specific EA stimulation inhibits PBG-induced vasodepression and bradycardia responses through a μ-opioid mechanism in the NTS.

  9. Subthalamic nucleus activity optimizes maximal effort motor responses in Parkinson's disease.

    PubMed

    Anzak, Anam; Tan, Huiling; Pogosyan, Alek; Foltynie, Thomas; Limousin, Patricia; Zrinzo, Ludvic; Hariz, Marwan; Ashkan, Keyoumars; Bogdanovic, Marko; Green, Alexander L; Aziz, Tipu; Brown, Peter

    2012-09-01

    The neural substrates that enable individuals to achieve their fastest and strongest motor responses have long been enigmatic. Importantly, characterization of such activities may inform novel therapeutic strategies for patients with hypokinetic disorders, such as Parkinson's disease. Here, we ask whether the basal ganglia may play an important role, not only in the attainment of maximal motor responses under standard conditions but also in the setting of the performance enhancements known to be engendered by delivery of intense stimuli. To this end, we recorded local field potentials from deep brain stimulation electrodes implanted bilaterally in the subthalamic nuclei of 10 patients with Parkinson's disease, as they executed their fastest and strongest handgrips in response to a visual cue, which was accompanied by a brief 96-dB auditory tone on random trials. We identified a striking correlation between both theta/alpha (5-12 Hz) and high-gamma/high-frequency (55-375 Hz) subthalamic nucleus activity and force measures, which explained close to 70% of interindividual variance in maximal motor responses to the visual cue alone, when patients were ON their usual dopaminergic medication. Loud auditory stimuli were found to enhance reaction time and peak rate of development of force still further, independent of whether patients were ON or OFF l-DOPA, and were associated with increases in subthalamic nucleus power over a broad gamma range. However, the contribution of this broad gamma activity to the performance enhancements observed was only modest (≤13%). The results implicate frequency-specific subthalamic nucleus activities as substantial factors in optimizing an individual's peak motor responses at maximal effort of will, but much less so in the performance increments engendered by intense auditory stimuli.

  10. Bilateral adaptive deep brain stimulation is effective in Parkinson's disease.

    PubMed

    Little, Simon; Beudel, Martijn; Zrinzo, Ludvic; Foltynie, Thomas; Limousin, Patricia; Hariz, Marwan; Neal, Spencer; Cheeran, Binith; Cagnan, Hayriye; Gratwicke, James; Aziz, Tipu Z; Pogosyan, Alex; Brown, Peter

    2016-07-01

    Adaptive deep brain stimulation (aDBS) uses feedback from brain signals to guide stimulation. A recent acute trial of unilateral aDBS showed that aDBS can lead to substantial improvements in contralateral hemibody Unified Parkinson's Disease Rating Scale (UPDRS) motor scores and may be superior to conventional continuous DBS in Parkinson's disease (PD). We test whether potential benefits are retained with bilateral aDBS and in the face of concurrent medication. We applied bilateral aDBS in 4 patients with PD undergoing DBS of the subthalamic nucleus. aDBS was delivered bilaterally with independent triggering of stimulation according to the amplitude of β activity at the corresponding electrode. Mean stimulation voltage was 3.0±0.1 volts. Motor assessments consisted of double-blinded video-taped motor UPDRS scores that included both limb and axial features. UPDRS scores were 43% (p=0.04; Cohen's d=1.62) better with aDBS than without stimulation. Motor improvement with aDBS occurred despite an average time on stimulation (ToS) of only 45%. Levodopa was well tolerated during aDBS and led to further reductions in ToS. Bilateral aDBS can improve both axial and limb symptoms and can track the need for stimulation across drug states. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  11. Homologous upregulation of sst2 somatostatin receptor expression in the rat arcuate nucleus in vivo.

    PubMed

    Tannenbaum, G S; Turner, J; Guo, F; Videau, C; Epelbaum, J; Beaudet, A

    2001-07-01

    In vitro studies using various cell systems have provided conflicting results regarding homologous regulation of somatostatin (SRIH) receptors, and information on whether SRIH regulates the expression of its own receptors in vivo is lacking. In the present study we examined, by in situ hybridization, the effects of pretreatment with the sst2-preferring SRIH analog, octreotide, in vivo, on mRNA levels of two SRIH receptor subtypes, sst1 and sst2, in rat brain and pituitary. (125)I-[DTrp(8)]-SRIH binding was also measured in these regions. Three hours after the iv injection of 50 microg octreotide to conscious adult male rats, there was a 46% increase (p < 0.01) in the labeling density of sst2 mRNA-expressing cells in the hypothalamic arcuate nucleus compared to normal saline-pretreated controls, but not in any of the other brain regions examined. Computer-assisted image analysis revealed that 3 h exposure to octreotide significantly (p < 0.01) augmented both the number and labeling density of sst2 mRNA-expressing cells in the arcuate nucleus, compared to those in saline-treated controls. By contrast, within the anterior pituitary gland, in vivo exposure to octreotide did not affect the expression of sst2 mRNA. No changes in sst1 mRNA-expressing cells were observed after octreotide treatment in any of the regions measured, indicating that the observed effects were homologous, i.e. specific of the receptor subtype stimulated. Octreotide pretreatment was also without effect on the density of (125)I-[DTrp(8)]-SRIH binding in either the arcuate nucleus or pituitary. These results demonstrate, for the first time, that SRIH preexposure in vivo upregulates the expression of a subtype of its own receptors, sst2, within the central nervous system. They further suggest that pretreatment with SRIH in vivo does not cause sst2 receptor desensitization in arcuate nucleus and pituitary. Such homologous regulatory mechanisms may play an important role in the neuroendocrine control

  12. Possibility of synthesizing a doubly magic superheavy nucleus

    NASA Astrophysics Data System (ADS)

    Aritomo, Y.

    2007-02-01

    The possibility of synthesizing a doubly magic superheavy nucleus, 298114184, is investigated on the basis of fluctuation-dissipation dynamics. In order to synthesize this nucleus, we must generate more neutron-rich compound nuclei because of the neutron emissions from excited compound nuclei. The compound nucleus 304114 has two advantages to achieving a high survival probability. First, because of low neutron separation energy and rapid cooling, the shell correction energy recovers quickly. Secondly, owing to neutron emissions, the neutron number in the nucleus approaches that of the double closed shell and the nucleus attains a large fission barrier. Because of these two effects, the survival probability of 304114 does not decrease until the excitation energy E*=50 MeV. These properties lead to a rather high evaporation residue cross section.

  13. Reduced cortical innervation of the subthalamic nucleus in MPTP-treated parkinsonian monkeys

    PubMed Central

    Mathai, Abraham; Ma, Yuxian; Paré, Jean-Francois; Villalba, Rosa M.; Wichmann, Thomas

    2015-01-01

    The striatum and the subthalamic nucleus are the main entry points for cortical information to the basal ganglia. Parkinson’s disease affects not only the function, but also the morphological integrity of some of these inputs and their synaptic targets in the basal ganglia. Significant morphological changes in the cortico-striatal system have already been recognized in patients with Parkinson’s disease and in animal models of the disease. To find out whether the primate cortico-subthalamic system is also subject to functionally relevant morphological alterations in parkinsonism, we used a combination of light and electron microscopy anatomical approaches and in vivo electrophysiological methods in monkeys rendered parkinsonian following chronic exposure to low doses of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). At the light microscopic level, the density of vesicular glutamate transporter 1-positive (i.e. cortico-subthalamic) profiles in the dorsolateral part of the subthalamic nucleus (i.e. its sensorimotor territory) was 26.1% lower in MPTP-treated parkinsonian monkeys than in controls. These results were confirmed by electron microscopy studies showing that the number of vesicular glutamate transporter 1-positive terminals and of axon terminals forming asymmetric synapses in the dorsolateral subthalamic nucleus was reduced by 55.1% and 27.9%, respectively, compared with controls. These anatomical findings were in line with in vivo electrophysiology data showing a 60% reduction in the proportion of pallidal neurons that responded to electrical stimulation of the cortico-subthalamic system in parkinsonian monkeys. These findings provide strong evidence for a partial loss of the hyperdirect cortico-subthalamic projection in MPTP-treated parkinsonian monkeys. PMID:25681412

  14. Cell Biology of the Caenorhabditis elegans Nucleus

    PubMed Central

    Cohen-Fix, Orna; Askjaer, Peter

    2017-01-01

    Studies on the Caenorhabditis elegans nucleus have provided fascinating insight to the organization and activities of eukaryotic cells. Being the organelle that holds the genetic blueprint of the cell, the nucleus is critical for basically every aspect of cell biology. The stereotypical development of C. elegans from a one cell-stage embryo to a fertile hermaphrodite with 959 somatic nuclei has allowed the identification of mutants with specific alterations in gene expression programs, nuclear morphology, or nuclear positioning. Moreover, the early C. elegans embryo is an excellent model to dissect the mitotic processes of nuclear disassembly and reformation with high spatiotemporal resolution. We review here several features of the C. elegans nucleus, including its composition, structure, and dynamics. We also discuss the spatial organization of chromatin and regulation of gene expression and how this depends on tight control of nucleocytoplasmic transport. Finally, the extensive connections of the nucleus with the cytoskeleton and their implications during development are described. Most processes of the C. elegans nucleus are evolutionarily conserved, highlighting the relevance of this powerful and versatile model organism to human biology. PMID:28049702

  15. Deep brain stimulation for the treatment of uncommon tremor syndromes.

    PubMed

    Ramirez-Zamora, Adolfo; Okun, Michael S

    2016-08-01

    Deep brain stimulation (DBS) has become a standard therapy for the treatment of select cases of medication refractory essential tremor and Parkinson's disease however the effectiveness and long-term outcomes of DBS in other uncommon and complex tremor syndromes has not been well established. Traditionally, the ventralis intermedius nucleus (VIM) of the thalamus has been considered the main target for medically intractable tremors; however alternative brain regions and improvements in stereotactic techniques and hardware may soon change the horizon for treatment of complex tremors. In this article, we conducted a PubMed search using different combinations between the terms 'Uncommon tremors', 'Dystonic tremor', 'Holmes tremor' 'Midbrain tremor', 'Rubral tremor', 'Cerebellar tremor', 'outflow tremor', 'Multiple Sclerosis tremor', 'Post-traumatic tremor', 'Neuropathic tremor', and 'Deep Brain Stimulation/DBS'. Additionally, we examined and summarized the current state of evolving interventions for treatment of complex tremor syndromes. Expert commentary: Recently reported interventions for rare tremors include stimulation of the posterior subthalamic area, globus pallidus internus, ventralis oralis anterior/posterior thalamic subnuclei, and the use of dual lead stimulation in one or more of these targets. Treatment should be individualized and dictated by tremor phenomenology and associated clinical features.

  16. The temporal relationship between non-respiratory burst activity of expiratory laryngeal motoneurons and phrenic apnoea during stimulation of the superior laryngeal nerve in rat

    PubMed Central

    Sun, Qi-Jian; Bautista, Tara G; Berkowitz, Robert G; Zhao, Wen-Jing; Pilowsky, Paul M

    2011-01-01

    Abstract A striking effect of stimulating the superior laryngeal nerve (SLN) is its ability to inhibit central inspiratory activity (cause ‘phrenic apnoea’), but the mechanism underlying this inhibition remains unclear. Here we demonstrate, by stimulating the SLN at varying frequencies, that the evoked non-respiratory burst activity recorded from expiratory laryngeal motoneurons (ELMs) has an intimate temporal relationship with phrenic apnoea. During 1–5 Hz SLN stimulation, occasional absences of phrenic nerve discharge (PND) occurred such that every absent PND was preceded by an ELM burst activity. During 10–20 Hz SLN stimulation, more bursts were evoked together with more absent PNDs, leading eventually to phrenic apnoea. Interestingly, subsequent microinjections of isoguvacine (10 mm, 20–40 nl) into ipsilateral Bötzinger complex (BötC) and contralateral nucleus tractus solitarii (NTS) significantly attenuated the apnoeic response but not the ELM burst activity. Our results suggest a bifurcating projection from NTS to both the caudal nucleus ambiguus and BötC, which mediates the closely related ELM burst and apnoeic response, respectively. We believe that such an intimate timing between laryngeal behaviour and breathing is crucial for the effective elaboration of the different airway protective behaviours elicited following SLN stimulation, including the laryngeal adductor reflex, swallowing and cough. PMID:21320890

  17. Chloroplast-to-nucleus communication

    PubMed Central

    Chan, Kai Xun; Crisp, Peter Alexander; Estavillo, Gonzalo Martin

    2010-01-01

    In order for plant cells to function efficiently under different environmental conditions, chloroplastic processes have to be tightly regulated by the nucleus. It is widely believed that there is inter-organelle communication from the chloroplast to the nucleus, called retrograde signaling. Although some pathways of communication have been identified, the actual signals that move between the two cellular compartments are largely unknown. This review provides an overview of retrograde signaling including its importance to the cell, candidate signals, recent advances and current experimental systems. In addition, we highlight the potential of using drought stress as a model for studying retrograde signaling. PMID:21512326

  18. Distinct populations of neurons respond to emotional valence and arousal in the human subthalamic nucleus

    PubMed Central

    Sieger, Tomáš; Serranová, Tereza; Růžička, Filip; Vostatek, Pavel; Wild, Jiří; Šťastná, Daniela; Bonnet, Cecilia; Novák, Daniel; Růžička, Evžen; Urgošík, Dušan; Jech, Robert

    2015-01-01

    Both animal studies and studies using deep brain stimulation in humans have demonstrated the involvement of the subthalamic nucleus (STN) in motivational and emotional processes; however, participation of this nucleus in processing human emotion has not been investigated directly at the single-neuron level. We analyzed the relationship between the neuronal firing from intraoperative microrecordings from the STN during affective picture presentation in patients with Parkinson’s disease (PD) and the affective ratings of emotional valence and arousal performed subsequently. We observed that 17% of neurons responded to emotional valence and arousal of visual stimuli according to individual ratings. The activity of some neurons was related to emotional valence, whereas different neurons responded to arousal. In addition, 14% of neurons responded to visual stimuli. Our results suggest the existence of neurons involved in processing or transmission of visual and emotional information in the human STN, and provide evidence of separate processing of the affective dimensions of valence and arousal at the level of single neurons as well. PMID:25713375

  19. In mammalian muscle, SIRT3 is present in mitochondria and not in the nucleus; and SIRT3 is upregulated by chronic muscle contraction in an adenosine monophosphate-activated protein kinase-independent manner.

    PubMed

    Gurd, Brendon J; Holloway, Graham P; Yoshida, Yuko; Bonen, Arend

    2012-05-01

    In selected cell lines, it appears (a) that metabolic stressors induce the translocation of SIRT3 from the nucleus to mitochondria and (b) that SIRT3 may contribute to the regulation of mitochondrial biogenesis and/or fatty acid utilization. We have examined in mammalian muscle (1) the association between SIRT3 protein content and muscle oxidative capacity and mitochondrial fatty acid oxidation, (2) the subcellular location of SIRT3, (3) whether exercise induces the translocation of SIRT3 from the nucleus to the mitochondria, and (4) the response of SIRT3 protein to stressors known to induce mitochondrial biogenesis (chronic muscle stimulation and 5-aminoimidazole-4-carboxamide-1-β-d-ribofuranoside administration). SIRT3 protein displayed hierarchical expression based on oxidative potential of muscle tissues (heart > red > white). In contrast to studies in some cell lines, metabolic stress (exercise) did not induce the translocation of SIRT3 from the nucleus to mitochondria, as SIRT3 was only present in subsarcolemmal (SS) and intermyofibrillar (IMF) mitochondria, not in the nucleus. Chronic stimulation increased muscle mitochondrial content and SIRT3 protein in SS (+33%) and IMF (+27%) mitochondria (P < .05). In contrast, chronic 5-aminoimidazole-4-carboxamide-1-β-d-ribofuranoside administration, while inducing mitochondrial biogenesis, did not alter SS or IMF mitochondrial SIRT3 protein content. These studies have shown that, in muscle, SIRT3 (a) scales with muscle oxidative capacity and with enzymes regulating fatty acid oxidation, (b) in resting muscle is localized to SS and IMF mitochondria and not nuclei, (c) in contracting muscle is not acutely translocated to mitochondria, and (d) is upregulated with chronic stimulation in an adenosine monophosphate-activated protein kinase-independent manner. Copyright © 2012 Elsevier Inc. All rights reserved.

  20. Actomyosin Pulls to Advance the Nucleus in a Migrating Tissue Cell

    PubMed Central

    Wu, Jun; Kent, Ian A.; Shekhar, Nandini; Chancellor, T.J.; Mendonca, Agnes; Dickinson, Richard B.; Lele, Tanmay P.

    2014-01-01

    The cytoskeletal forces involved in translocating the nucleus in a migrating tissue cell remain unresolved. Previous studies have variously implicated actomyosin-generated pushing or pulling forces on the nucleus, as well as pulling by nucleus-bound microtubule motors. We found that the nucleus in an isolated migrating cell can move forward without any trailing-edge detachment. When a new lamellipodium was triggered with photoactivation of Rac1, the nucleus moved toward the new lamellipodium. This forward motion required both nuclear-cytoskeletal linkages and myosin activity. Apical or basal actomyosin bundles were found not to translate with the nucleus. Although microtubules dampen fluctuations in nuclear position, they are not required for forward translocation of the nucleus during cell migration. Trailing-edge detachment and pulling with a microneedle produced motion and deformation of the nucleus suggestive of a mechanical coupling between the nucleus and the trailing edge. Significantly, decoupling the nucleus from the cytoskeleton with KASH overexpression greatly decreased the frequency of trailing-edge detachment. Collectively, these results explain how the nucleus is moved in a crawling fibroblast and raise the possibility that forces could be transmitted from the front to the back of the cell through the nucleus. PMID:24411232