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1

Basal Ganglia Shape Abnormalities in the Unaffected Siblings of Schizophrenia Patients  

PubMed Central

Objective Abnormalities of basal ganglia structure in schizophrenia have been attributed to the effects of antipsychotic drugs. Our aim was to test the hypothesis that abnormalities of basal ganglia structure are intrinsic features of schizophrenia, by assessing basal ganglia volume and shape in the unaffected siblings of schizophrenia subjects. Method The study involved 25 pairs of schizophrenia subjects and their unaffected siblings and 40 pairs of healthy controls and their siblings. Large deformation, high-dimensional brain mapping was used to obtain surface representations of the caudate, putamen, and globus pallidus. Surfaces were derived from transformations of anatomical templates and shapes were analyzed using reduced-dimensional measures of surface variability (i.e. principal components and canonical analysis). Canonical functions were derived using schizophrenia and control groups, and were then used to compare shapes in the sibling groups. To visualize shape differences, maps of the estimated surface displacement between groups were created. Results In the caudate, putamen and globus pallidus, the degree of shape abnormality observed in the siblings of the schizophrenia subjects was intermediate between the schizophrenia subjects and the controls. In the schizophrenia subjects, significant correlations were observed between measures of caudate, putamen and globus pallidus structure and the selected measures of lifetime psychopathology. Conclusions Attenuated abnormalities of basal ganglia structure are present in the unaffected siblings of schizophrenia subjects. This finding implies that basal ganglia structural abnormalities observed in subjects with schizophrenia are at least in part an intrinsic feature of the illness. PMID:18295189

Mamah, Daniel; Harms, Michael P.; Wang, Lei; Barch, Deanna; Thompson, Paul; Kim, Jaeyun; Miller, Michael I.; Csernansky, John G.

2008-01-01

2

Basal Ganglia and Learning  

NSDL National Science Digital Library

The basal ganglia, a group of interconnected brain areas located deep in the cerebral cortex, have proved to be at work in learning, the formation of good and bad habits, and some psychiatric and addictive disorders.

2009-04-14

3

Distinct basal ganglia hyperechogenicity in idiopathic basal ganglia calcification.  

PubMed

We report a 67-year-old patient with idiopathic basal ganglia calcification (IBGC). He presented with progressive cognitive impairment, frontal lobe dysfunction, mild leg spasticity, and levodopa (L-dopa)-responsive parkinsonism. Transcranial sonography (TCS) revealed marked hyperechogenicity of the basal ganglia and periventricular spaces bilaterally. The detected signal alterations showed a fairly symmetric distribution and corresponded to the hyperintense calcifications depicted on the computer tomography brain scan. The combination of symmetric hyperechogenic areas adjacent to the lateral ventricles and of the basal ganglia may serve as an imaging marker characteristic of IBGC. Hyperechogenicity due to extended basal ganglia calcification as presented here is distinct from the pattern of hyperechogenicity caused by heavy metal accumulation, which is described to be less striking. In addition to atypical parkinsonian syndromes such as progressive supranuclear palsy and multiple system atrophy, IBGC is thus another differential diagnosis of parkinsonism with basal ganglia hyperechogenicity. PMID:20803519

Brüggemann, Norbert; Schneider, Susanne A; Sander, Thurid; Klein, Christine; Hagenah, Johann

2010-11-15

4

Basal ganglia echogenicity in tauopathies.  

PubMed

Accumulating data confirm the usefulness of transcranial sonography (TCS) in the diagnosis of Parkinson's disease. The relevance of basal ganglia abnormalities depicted by TCS in atypical parkinsonian syndromes still needs further assessment. In the present study, 20 patients with progressive supranuclear palsy (PSP) and 13 patients with corticobasal syndrome (CBS) were studied with the use of transcranial sonography. Echogenicity of the substantia nigra (SN) and lenticular nucleus (LN) were assessed. 0/20 patients with PSP and 8/12 (66.6 %) patients with CBS were characterized with SN hyperechogenicity. LN hyperechogenicity was observed in 9/20 patients diagnosed with PSP and 0/11 of CBS patients. The combination of SN isoechogenicity and LN hyperechogenicity reached 100 % sensitivity and positive predictive value for the diagnosis of PSP. The results of this study point out that CBS has to be taken into consideration when SN hyperechogenicity is depicted in a patient with parkinsonian syndrome. Normal echogenicity of the SN coexisting with LN hyperechogenicity practically excludes CBS. PMID:25204278

Sadowski, Krzysztof; Serafin-Król, Ma?gorzata; Szlachta, Karol; Friedman, Andrzej

2014-09-10

5

Bilateral basal ganglia calcifications visualised on CT scan.  

PubMed Central

Thirty-eight cases of basal ganglia calcification imaged on computed axial tomography were reviewed. Most cases were felt to represent senescent calcification. The possibility of a vascular aetiology in this group is discussed. A less common group of patients was identified with calcification secondary to abnormalities in calcium metabolism or radiation therapy. Three cases of basal ganglia calcifications were detected in juvenile epileptic patients receiving chronic anticonvulsants. These cases may be related to abnormalities in calcium metabolism and alkaline phosphatase activity. Clinical evidence of basal ganglia abnormality was generally absent demonstrating the preservation of neuronal pathways in most cases. PMID:7420090

Brannan, T S; Burger, A A; Chaudhary, M Y

1980-01-01

6

Basal Ganglia Shapes Predict Social, Communication, and Motor Dysfunctions in Boys with Autism Spectrum Disorder  

ERIC Educational Resources Information Center

Objective: Basal ganglia abnormalities have been suggested as contributing to motor, social, and communicative impairments in autism spectrum disorder (ASD). Volumetric analyses offer limited ability to detect localized differences in basal ganglia structure. Our objective was to investigate basal ganglia shape abnormalities and their association…

Qiu, Anqi; Adler, Marcy; Crocetti, Deana; Miller, Michael I.; Mostofsky, Stewart H.

2010-01-01

7

Basal ganglia lesions in children and adults.  

PubMed

The term "basal ganglia" refers to caudate and lentiform nuclei, the latter composed of putamen and globus pallidus, substantia nigra and subthalamic nuclei and these deep gray matter structures belong to the extrapyramidal system. Many diseases may present as basal ganglia abnormalities. Magnetic resonance imaging (MRI) and computed tomography (CT) - to a lesser degree - allow for detection of basal ganglia injury. In many cases, MRI alone does not usually allow to establish diagnosis but together with the knowledge of age and circumstances of onset and clinical course of the disease is a powerful tool of differential diagnosis. The lesions may be unilateral: in Rassmussen encephalitis, diabetes with hemichorea/hemiballism and infarction or - more frequently - bilateral in many pathologic conditions. Restricted diffusion is attributable to infarction, acute hypoxic-ischemic injury, hypoglycemia, Leigh disease, encephalitis and CJD. Contrast enhancement may be seen in cases of infarction and encephalitis. T1-hyperintensity of the lesions is uncommon and may be observed unilaterally in case of hemichorea/hemiballism and bilaterally in acute asphyxia in term newborns, in hypoglycemia, NF1, Fahr disease and manganese intoxication. Decreased signal intensity on GRE/T2*-weighted images and/or SWI indicating iron, calcium or hemosiderin depositions is observed in panthotenate kinase-associated neurodegeneration, Parkinson variant of multiple system atrophy, Fahr disease (and other calcifications) as well as with the advancing age. There are a few papers in the literature reviewing basal ganglia lesions. The authors present a more detailed review with rich iconography from the own archive. PMID:23313708

Bekiesinska-Figatowska, Monika; Mierzewska, Hanna; Jurkiewicz, El?bieta

2013-05-01

8

Basal Ganglia Volumes in Patients With Gilles de la Tourette Syndrome  

Microsoft Academic Search

Background: Despite strong circumstantial evidence that the pathophysiology of Gilles de la Tourette syndrome (TS) involves structural and functional disturbances of the basal ganglia, inconsistent findings from relatively small in vivo TS imaging studies have supported contradictory conclu- sions concerning the role of abnormal anatomical charac- teristics of the basal ganglia in the pathophysiology of TS. Methods: Basal ganglia volumes

Bradley S. Peterson; Prakash Thomas; Michael J. Kane; Lawrence Scahill; Heping Zhang; Richard Bronen; Robert A. King; James F. Leckman; Lawrence Staib

2003-01-01

9

The Basal Ganglia-Circa 1982  

NASA Technical Reports Server (NTRS)

Our review has shown that recent studies with the new anterograde and retrograde axon transport methods have confirmed and extended our knowledge of the projection of the basal ganglia and clarified their sites of origin. They have thrown new light on certain topographic connectional relationships and revealed several new reciprocal connections between constituent nuclei of the basal ganglia. Similarly, attention has been drawn to the fact that there have also been many new histochemical techniques introduced in recent years that are now providing regional biochemical overlays for connectional maps of the central nervous system, especially regions in, or interconnecting with, the basal ganglia. However, although these new morphological biochemical maps are very complex and technically highly advanced, our understanding of the function controlled by the basal ganglia still remains primitive. The reader who is interested in some new ideas of the functional aspects of the basal ganglia is directed to Nauta's proposed conceptual reorganization of the basal ganglia telencephalon and to Marsden's more clinically orientated appraisal of the unsolved mysteries of the basal ganglia participation in the control of movement.

Mehler, William R.

1981-01-01

10

Computer Modeling in Basal Ganglia Disorders  

Microsoft Academic Search

The last two decades have witnessed an increasing interest in the use of computational modeling and mathematical analysis\\u000a as tools to unravel the complex neural mechanisms and computational algorithms underlying the function of the basal ganglia\\u000a and related structures under normal and neurological conditions (1–3). Computational modeling of basal ganglia disorders has until recently been focused on Parkinson’s disease (PD),

José Luis Contreras-Vidal

11

THE BASAL GANGLIA: FOCUSED SELECTION AND INHIBITION OF COMPETING MOTOR PROGRAMS  

Microsoft Academic Search

The basal ganglia comprise several nuclei in the forebrain, diencephalon, and midbrain thought to play a significant role in the control of posture and movement. It is well recognized that people with degenerative diseases of the basal ganglia suffer from rigidly held abnormal body postures, slowing of movement, involuntary movements, or a combination of these abnormalities. However, it has not

JONATHAN W MINK

1996-01-01

12

Linear Branching Echogenicities in the Basal Ganglia and Thalami  

Microsoft Academic Search

Echogenic vasculature in the basal ganglia and thalami of neonatal brain have been associated with congeni- tal infections such as cytomegalovirus (CMV), rubella, and syphilis, trisomy 13 syndrome, Down syndrome, maternal drug use, neonatal asphyxia, nonimmune hydrops, and fetal alcohol syndrome. This abnormality is believed to result from necrotizing vasculitis with subsequent mineralization. In our study, we encountered 8 small

Han-Hsi Wang; Chih-Hao Chien; Min-Hou Liao; Yu-Nian Wu; Yu-Hsien Su

1998-01-01

13

Genetics Home Reference: Biotin-thiamine-responsive basal ganglia disease  

MedlinePLUS

... Recent literature OMIM Genetic disorder catalog Conditions > Biotin-thiamine-responsive basal ganglia disease On this page: Description ... Glossary definitions Reviewed January 2014 What is biotin-thiamine-responsive basal ganglia disease? Biotin-thiamine-responsive basal ...

14

Basal ganglia circuits changes in Parkinson’s disease patients  

PubMed Central

Functional changes in basal ganglia circuitry are responsible for the major clinical features of Parkinson’s disease (PD). Current models of basal ganglia circuitry can only partially explain the cardinal symptoms in PD. We used functional MRI to investigate the causal connectivity of basal ganglia networks from the substantia nigra pars compacta (SNc) in PD in the movement and resting state. In controls, SNc activity predicted increased activity in the supplementary motor area, the default mode network, and dorsolateral prefrontal cortex, but, in patients, activity predicted decreases in the same structures. The SNc had decreased connectivity with the striatum, globus pallidus, subthalamic nucleus, thalamus, supplementary motor area, dorsolateral prefrontal cortex, insula, default mode network, temporal lobe, cerebellum, and pons in patients compared to controls. Levodopa administration partially normalized the pattern of connectivity. Our findings show how the dopaminergic system exerts influences on widespread brain networks, including motor and cognitive networks. The pattern of basal ganglia network connectivity is abnormal in PD secondary to dopamine depletion, and is more deviant in more severe disease. Use of functional MRI with network analysis appears to be a useful method to demonstrate basal ganglia pathways in vivo in human subjects. PMID:22813979

Wu, Tao; Wang, Jue; Wang, Chaodong; Hallett, Mark; Zang, Yufeng; Wu, Xiaoli; Chan, Piu

2014-01-01

15

Extrastriatal Dopaminergic Circuits of the Basal Ganglia  

PubMed Central

The basal ganglia are comprised of the striatum, the external and internal segment of the globus pallidus (GPe and GPi, respectively), the subthalamic nucleus (STN), and the substantia nigra pars compacta and reticulata (SNc and SNr, respectively). Dopamine has long been identified as an important modulator of basal ganglia function in the striatum, and disturbances of striatal dopaminergic transmission have been implicated in diseases such as Parkinson's disease (PD), addiction and attention deficit hyperactivity disorder. However, recent evidence suggests that dopamine may also modulate basal ganglia function at sites outside of the striatum, and that changes in dopaminergic transmission at these sites may contribute to the symptoms of PD and other neuropsychiatric disorders. This review summarizes the current knowledge of the anatomy, functional effects and behavioral consequences of the dopaminergic innervation to the GPe, GPi, STN, and SNr. Further insights into the dopaminergic modulation of basal ganglia function at extrastriatal sites may provide us with opportunities to develop new and more specific strategies for treating disorders of basal ganglia dysfunction. PMID:21103009

Rommelfanger, Karen S.; Wichmann, Thomas

2010-01-01

16

Psychosis revealing familial idiopathic basal ganglia calcification.  

PubMed

We describe the case of a 39-year-old woman presenting with auditory hallucinations and delusions responsive to antipsychotic drugs. Computerized tomography scans revealed basal ganglia calcifications in the proband and in her two asymptomatic parents. Extensive etiological clinicobiological assessment allowed us to exclude known causes of brain calcifications and diagnose familial idiopathic basal ganglia calcification (IBGC). Neurological symptoms associated with psychiatric symptoms are common in IBGC. Nevertheless, purely psychiatric presentations, as demonstrated by the present case, are possible. However, a fortuitous association between asymptomatic IBGC and schizophrenia cannot be ruled out. Only brain imaging, followed by an extensive etiological assessment, allows for diagnosis of this rare disorder. PMID:23122487

Nicolas, Gaël; Guillin, Olivier; Borden, Alaina; Bioux, Sandrine; Lefaucheur, Romain; Hannequin, Didier

2013-01-01

17

The basal ganglia Ann M. Graybiel  

E-print Network

of the basal ganglia lead to devastating motor disorders, including Parkinson's disease and Huntington-brain stimulation procedures used to relieve Parkinson's disease. The subthalamic nucleus is a key structure controlling pallidal function, and is an increasingly favored site for deep-brain stimulation in the treatment

Graybiel, Ann M.

18

Functional anatomy of the basal ganglia. I. The cortico-basal ganglia-thalamo-cortical loop  

Microsoft Academic Search

This paper reviews some of the recent findings on different aspects of the anatomical organization of the basal ganglia. Attempts have been made to delineate the anatomical substrate of information processing along the cortico-basal ganglia-thalamo-cortical loop. Emphasis has been placed on data obtained with highly sensitive anterograde tract-tracing methods applied to the study of the main axis of the loop,

André Parent; Lili-Naz Hazrati

1995-01-01

19

368 Dispatch Basal ganglia: New therapeutic approaches to Parkinson's disease  

E-print Network

368 Dispatch Basal ganglia: New therapeutic approaches to Parkinson's disease Ann M. Graybiel As the search for molecular therapies for basal ganglia disorders, such as Parkinson's disease, accelerates, new-9822 The motor symptoms of basal ganglia disorders fall at two extremes. In Parkinson's disease and related

Graybiel, Ann M.

20

Oscillators and Oscillations in the Basal Ganglia.  

PubMed

What is the meaning of an action potential? There must be different answers for neurons that fire spontaneously, even in the absence of synaptic input, and those driven to fire from a resting membrane potential. In spontaneously firing neurons, the occurrence of the next action potential is guaranteed; only variations in its timing can carry the message. In the basal ganglia, the globus pallidus, the substantia nigra, and the subthalamic nucleus consist of neurons firing spontaneously. They each receive thousands of synaptic inputs, but these are not required to maintain their background firing. Instead, synaptic interactions among basal ganglia nuclei comprise a system of coupled oscillators that produces a complex resting pattern of activity. Normally, this pattern is highly irregular and uncorrelated, so that the firing of each cell is statistically independent of the others. This maximizes the potential information that may be transmitted by the basal ganglia to its target structures. In Parkinson's disease, the resting pattern of activity is dominated by a slow oscillation shared by nearly all of the neurons. Treatment with deep brain stimulation may gain its therapeutic value by disrupting this shared pathological oscillation, and restoring independent action by each neuron in the network. PMID:25449134

Wilson, Charles J

2014-12-01

21

The significance of the incidental finding of basal ganglia calcification on computed tomography.  

PubMed Central

Basal ganglia calcification was found as an incidental finding in 42 out of 7000 patients who underwent computed tomography. The calcification showed on plain skull radiography when the maximum density on computed tomography exceeded 100 Hounsfield units. The 26 patients with basal ganglia calcification detected on computed tomography who were available for follow-up, were investigated with matched controls. No clinical features of basal ganglia calcification were noted. Twenty-four patients had no significant metabolic abnormality and two patients had parathyroid disorder identified. PMID:7334414

Harrington, M G; Macpherson, P; McIntosh, W B; Allam, B F; Bone, I

1981-01-01

22

Basal ganglia and thalamic morphology in schizophrenia and bipolar disorder  

E-print Network

Basal ganglia and thalamic morphology in schizophrenia and bipolar disorder Fay Y. Womer a,n , Lei of the basal ganglia and thalamus in bipolar disorder (BP), schizophrenia-spectrum disorders (SCZ in neuroimaging studies. & 2014 Elsevier Ireland Ltd. All rights reserved. 1. Introduction Differentiating bipolar

23

A Search For Principles of Basal Ganglia Function  

E-print Network

million neurons in humans. Dierent modes of basal ganglia dysfunction lead to Parkinson's disease and Huntington's disease, which have debilitating motor and cognitive symptoms. However, despite intensive study basal ganglia function, with a focus on signal representation, computation, dynamics, and plasticity

Anderson, Charles H.

24

Interferon-? induces progressive nigrostriatal degeneration and basal ganglia calcification.  

PubMed

We found that CNS-directed expression of interferon-? (IFN-?) resulted in basal ganglia calcification, reminiscent of human idiopathic basal ganglia calcification (IBGC), and nigrostriatal degeneration. Our results indicate that IFN-? mediates age-progressive nigrostriatal degeneration in the absence of exogenous stressors. Further study of this model may provide insight into selective nigrostriatal degeneration in human IBGC and other Parkinson syndromes. PMID:21572432

Chakrabarty, Paramita; Ceballos-Diaz, Carolina; Lin, Wen-Lang; Beccard, Amanda; Jansen-West, Karen; McFarland, Nikolaus R; Janus, Christopher; Dickson, Dennis; Das, Pritam; Golde, Todd E

2011-06-01

25

Interferon-? induces progressive nigrostriatal degeneration and basal ganglia calcification  

PubMed Central

We report that CNS directed expression of Interferon (IFN) -? results in basal ganglia calcification, reminiscent of human idiopathic basal ganglia calcification (IBGC), and nigrostriatal degeneration. Our results show that IFN-? mediates age-progressive nigrostriatal degeneration in the absence of exogenous stressors. Further study of this model may provide unique insight into selective nigrostriatal degeneration in human IBGC and other Parkinson syndromes. PMID:21572432

Chakrabarty, Paramita; Ceballos-Diaz, Carolina; Lin, Wen-Lang; Beccard, Amanda; Jansen-West, Karen; McFarland, Nikolaus R; Janus, Christopher; Dickson, Dennis; Das, Pritam; Golde, Todd E

2013-01-01

26

Basal ganglia calcification and psychosis in Down's syndrome.  

PubMed Central

A case of basal ganglia calcification (diagnosed in vivo) and schizophreniform psychosis occurring in a young adult with Down's syndrome is reported. A stress-vulnerability model is suggested. Because of the relatively high prevalence of basal ganglia calcification to Down's syndrome, this population appears well suited for systematic study of the neuropsychiatric aspects associated with this neurological condition. Images Fig. 1 PMID:6231537

Thase, M. E.

1984-01-01

27

Calcification of the basal ganglia following carbon monoxide poisoning  

Microsoft Academic Search

Minor calcification of the basal ganglia was demonstrated by computed tomography in a woman, aged 66, who had survived carbon monoxide poisoning 48 years earlier. Extensive neuropathological investigations have demonstrated calcified lesions of the basal ganglia in a number of conditions, but their frequency and topographic distribution in vivo remain to be elucidated, by means of CT.

F. Illum

1980-01-01

28

Basal ganglia intensity indices and diffusion weighted imaging in manganese-exposed welders  

PubMed Central

Objectives Manganese exposure leads to diffuse cerebral metal deposition with the highest concentration in the globus pallidus associated with increased T1-weighted MRI signal. T1 signal intensity in extra-pallidal basal ganglia (caudate and putamen) has not been studied in occupationally exposed workers. Diffusion weighted imaging is a non-invasive measure of neuronal damage and may provide a quantification of neurotoxicity associated with welding and manganese exposure. This study investigated extra-pallidal T1 basal ganglia signal intensity as a marker of manganese exposure and basal ganglia diffusion weighted imaging abnormalities as a potential marker of neurotoxicity. Methods A 3T MR case:control imaging study was performed on 18 welders and 18 age- and gender-matched controls. Basal ganglia regions of interest were identified for each subject. T1-weighted intensity indices and apparent diffusion coefficients were generated for each region. Results All regional indices were higher in welders than controls (p?0.05). Combined basal ganglia (?=0.610), caudate (?=0.645), anterior (?=0.595) and posterior putamen (?=0.511) indices were more correlated with exposure than pallidal (?=0.484) index. Welder apparent diffusion coefficient values were lower than controls for globus pallidus (p=0.03) and anterior putamen (p=0.004). Conclusions Welders demonstrated elevated T1 indices throughout the basal ganglia. Combined basal ganglia, caudate and putamen indices were more correlated with exposure than pallidal index suggesting more inclusive basal ganglia sampling results in better exposure markers. Elevated indices were associated with diffusion weighted abnormalities in the pallidum and anterior putamen suggesting neurotoxicity in these regions. PMID:22447645

Criswell, Susan R; Perlmutter, Joel S; Huang, John L; Golchin, Nima; Flores, Hubert P; Hobson, Angela; Aschner, Michael; Erikson, Keith M; Checkoway, Harvey; Racette, Brad A

2013-01-01

29

Interactions between the Midbrain Superior Colliculus and the Basal Ganglia  

PubMed Central

An important component of the architecture of cortico-basal ganglia connections is the parallel, re-entrant looped projections that originate and return to specific regions of the cerebral cortex. However, such loops are unlikely to have been the first evolutionary example of a closed-loop architecture involving the basal ganglia. A phylogenetically older, series of subcortical loops can be shown to link the basal ganglia with many brainstem sensorimotor structures. While the characteristics of individual components of potential subcortical re-entrant loops have been documented, the full extent to which they represent functionally segregated parallel projecting channels remains to be determined. However, for one midbrain structure, the superior colliculus (SC), anatomical evidence for closed-loop connectivity with the basal ganglia is robust, and can serve as an example against which the loop hypothesis can be evaluated for other subcortical structures. Examination of ascending projections from the SC to the thalamus suggests there may be multiple functionally segregated systems. The SC also provides afferent signals to the other principal input nuclei of the basal ganglia, the dopaminergic neurones in substantia nigra and to the subthalamic nucleus. Recent electrophysiological investigations show that the afferent signals originating in the SC carry important information concerning the onset of biologically significant events to each of the basal ganglia input nuclei. Such signals are widely regarded as crucial for the proposed functions of selection and reinforcement learning with which the basal ganglia have so often been associated. PMID:20941324

Redgrave, Peter; Coizet, Veronique; Comoli, Eliane; McHaffie, John G.; Leriche, Mariana; Vautrelle, Nicolas; Hayes, Lauren M.; Overton, Paul

2010-01-01

30

Familial calcification of the basal ganglia with cerebrospinal fluid pleocytosis.  

PubMed Central

Two related infants with microcephaly, spastic quadriplegia, and profound retardation are reported. Both showed extensive bilateral symmetrical calcification of the basal ganglia with cerebrospinal fluid pleocytosis. Images PMID:3712392

Mehta, L; Trounce, J Q; Moore, J R; Young, I D

1986-01-01

31

Neural Representation of Time in Cortico-basal Ganglia Circuits  

E-print Network

Encoding time is universally required for learning and structuring motor and cognitive actions, but how the brain keeps track of time is still not understood. We searched for time representations in cortico-basal ganglia ...

Jin, Dezhe Z.

32

Short latency cerebellar modulation of the basal ganglia.  

PubMed

The graceful, purposeful motion of our body is an engineering feat that remains unparalleled in robotic devices using advanced artificial intelligence. Much of the information required for complex movements is generated by the cerebellum and the basal ganglia in conjunction with the cortex. Cerebellum and basal ganglia have been thought to communicate with each other only through slow, multi-synaptic cortical loops, begging the question as to how they coordinate their outputs in real time. We found that the cerebellum rapidly modulates the activity of the striatum via a disynaptic pathway in mice. Under physiological conditions, this short latency pathway was capable of facilitating optimal motor control by allowing the basal ganglia to incorporate time-sensitive cerebellar information and by guiding the sign of cortico-striatal plasticity. Conversely, under pathological condition, this pathway relayed aberrant cerebellar activity to the basal ganglia to cause dystonia. PMID:25402853

Chen, Christopher H; Fremont, Rachel; Arteaga-Bracho, Eduardo E; Khodakhah, Kamran

2014-12-01

33

Cognitive-motor interactions of the basal ganglia in development  

PubMed Central

Neural circuits linking activity in anatomically segregated populations of neurons in subcortical structures and the neocortex throughout the human brain regulate complex behaviors such as walking, talking, language comprehension, and other cognitive functions associated with frontal lobes. The basal ganglia, which regulate motor control, are also crucial elements in the circuits that confer human reasoning and adaptive function. The basal ganglia are key elements in the control of reward-based learning, sequencing, discrete elements that constitute a complete motor act, and cognitive function. Imaging studies of intact human subjects and electrophysiologic and tracer studies of the brains and behavior of other species confirm these findings. We know that the relation between the basal ganglia and the cerebral cortical region allows for connections organized into discrete circuits. Rather than serving as a means for widespread cortical areas to gain access to the motor system, these loops reciprocally interconnect a large and diverse set of cerebral cortical areas with the basal ganglia. Neuronal activity within the basal ganglia associated with motor areas of the cerebral cortex is highly correlated with parameters of movement. Neuronal activity within the basal ganglia and cerebellar loops associated with the prefrontal cortex is related to the aspects of cognitive function. Thus, individual loops appear to be involved in distinct behavioral functions. Damage to the basal ganglia of circuits with motor areas of the cortex leads to motor symptoms, whereas damage to the subcortical components of circuits with non-motor areas of the cortex causes higher-order deficits. In this report, we review some of the anatomic, physiologic, and behavioral findings that have contributed to a reappraisal of function concerning the basal ganglia and cerebellar loops with the cerebral cortex and apply it in clinical applications to attention deficit/hyperactivity disorder (ADHD) with biomechanics and a discussion of retention of primitive reflexes being highly associated with the condition. PMID:24592214

Leisman, Gerry; Braun-Benjamin, Orit; Melillo, Robert

2014-01-01

34

Update on models of basal ganglia function and dysfunction  

PubMed Central

Circuit models of basal ganglia function and dysfunction have undergone significant changes over time. The previous view that the basal ganglia are centers in which massive convergence of cortical information occurred has now been replaced by a view in which these structures process information in a highly specific manner, participating in anatomical and functional modules that also involve cortex and thalamus. In addition, much has been learned about the intrinsic connections of the basal ganglia. While the basal ganglia-thalamocortical circuitry was originally seen almost exclusively in its relationship to the control of movement, these structures are now viewed as essential for higher level behavioral control, for instance in the regulation of habit learning or action selection. Probably the greatest benefit of these models has been that they have motivated a wealth of studies of the pathophysiology of movement disorders of basal ganglia origin, such as Parkinson’s disease. Such studies, in turn, have helped to reshape the existing circuit models. In this paper we review these fascinating changes of our appreciation of the basal ganglia circuitry, and comment on the current state of our knowledge in this field. PMID:20082999

DeLong, Mahlon; Wichmann, Thomas

2014-01-01

35

BASAL GANGLIA PATHOLOGY IN SCHIZOPHRENIA: DOPAMINE CONNECTIONS and ANOMALIES  

PubMed Central

Schizophrenia is a severe mental illness that affects 1% of the world population. The disease usually manifests itself in early adulthood with hallucinations, delusions, cognitive and emotional disturbances and disorganized thought and behavior. Dopamine was the first neurotransmitter to be implicated in the disease, and though no longer the only suspect in schizophrenia pathophysiology, it obviously plays an important role. The basal ganglia are the site of most of the dopamine neurons in the brain and the target of antipsychotic drugs. In this review we will start with an overview of basal ganglia anatomy emphasizing dopamine circuitry. Then, we will review the major deficits in dopamine function in schizophrenia, emphasizing the role of excessive dopamine in the basal ganglia and the link to psychosis. PMID:20089137

Perez-Costas, Emma; Melendez-Ferro, Miguel; Roberts, Rosalinda C.

2010-01-01

36

Time representation in reinforcement learning models of the basal ganglia  

PubMed Central

Reinforcement learning (RL) models have been influential in understanding many aspects of basal ganglia function, from reward prediction to action selection. Time plays an important role in these models, but there is still no theoretical consensus about what kind of time representation is used by the basal ganglia. We review several theoretical accounts and their supporting evidence. We then discuss the relationship between RL models and the timing mechanisms that have been attributed to the basal ganglia. We hypothesize that a single computational system may underlie both RL and interval timing—the perception of duration in the range of seconds to hours. This hypothesis, which extends earlier models by incorporating a time-sensitive action selection mechanism, may have important implications for understanding disorders like Parkinson's disease in which both decision making and timing are impaired. PMID:24409138

Gershman, Samuel J.; Moustafa, Ahmed A.; Ludvig, Elliot A.

2014-01-01

37

Multidimensional Sequence Learning in Patients with Focal Basal Ganglia Lesions  

ERIC Educational Resources Information Center

Parkinson's patients have been found to be impaired in learning movement sequences. In the current study, patients with unilateral basal ganglia lesions due to stroke were tested on a serial reaction time task in which responses were based on the spatial location of each stimulus. The spatial locations either followed a fixed sequence or were…

Shin, J.C.; Aparicio, P.; Ivry, R.B.

2005-01-01

38

Basal ganglia and thalamic tumours: an imaging approximation  

Microsoft Academic Search

Introduction. Among brain tumours, those arising from the deep brain are rare. In many cases they are low-grade astrocytomas. But primitive neuroectodermal tumours, ganglion cell tumours, oligodendrogliomas, lymphomas, and germinal neoplasms can also grow up from the basal ganglia and thalamic region. In other occasions peripheral neoplasms developing in neighbouring structures like the cerebral lobes, the ventricular walls, choroidal plexus,

José M. García-Santos; Silvia Torres del Río; Ana Sánchez; Juan F. Martínez-Lage

2002-01-01

39

Mephedrone alters basal ganglia and limbic neurotensin systems.  

PubMed

Mephedrone (4-methylmethcathinone) is a synthetic cathinone designer drug that alters pre-synaptic dopamine (DA) activity like many psychostimulants. However, little is known about the post-synaptic dopaminergic impacts of mephedrone. The neuropeptide neurotensin (NT) provides inhibitory feedback for basal ganglia and limbic DA pathways, and post-synaptic D1 -like and D2 -like receptor activity affects NT tissue levels. This study evaluated how mephedrone alters basal ganglia and limbic system NT content and the role of NT receptor activation in drug consumption behavior. Four 25 mg/kg injections of mephedrone increased NT content in basal ganglia (striatum, substantia nigra and globus pallidus) and the limbic regions (nucleus accumbens core), while a lower dosage (5 mg/kg/injection) only increased striatal NT content. Mephedrone-induced increases in basal ganglia NT levels were mediated by D1 -like receptors in the striatum and the substantia nigra by both D1 -like and D2 -like receptors in the globus pallidus. Mephedrone increased substance P content, another neuropeptide, in the globus pallidus, but not in the dorsal striatum or substantia nigra. Finally, the NT receptor agonist PD149163 blocked mephedrone self-administration, suggesting reduced NT release, as indicated by increased tissue levels, likely contributing to patterns of mephedrone consumption. PMID:24678634

German, Christopher L; Hoonakker, Amanda H; Fleckenstein, Annette E; Hanson, Glen R

2014-08-01

40

Lesch–Nyhan disease and the basal ganglia  

Microsoft Academic Search

The purpose of this review is to summarize emerging evidence that the neurobehavioral features of Lesch–Nyhan disease (LND), a developmental disorder caused by congenital deficiency of the purine salvage enzyme hypoxanthine–guanine phosphoribosyltransferase (HPRT), may be attributable to dysfunction of the basal ganglia. Affected individuals have severe motor disability described by prominent extrapyramidal features that are characteristic of dysfunction of the

J. E Visser; P. R Bär; H. A Jinnah

2000-01-01

41

Basal ganglia morphology links the metabolic syndrome and depressive symptoms  

PubMed Central

The metabolic syndrome (MetS) is a clustering of cardiovascular and cerebrovascular risk factors that are often comorbid with depressive symptoms. Individual components of the MetS also covary with the morphology of basal ganglia regions that are altered by depression. However, it remains unknown whether the covariation between the MetS and depressive symptomatology can be accounted for in part by morphological changes in the basal ganglia. Accordingly, we tested the hypothesis that increased depressive symptoms among individuals with the MetS might be statistically mediated by reduced grey matter volume in basal ganglia regions. The presence of the MetS was determined in 147 middle-aged adults using the criteria of the National Cholesterol Education Program, Adult Treatment Panel III. Basal ganglia volumes were determined on an a priori basis by automated segmentation of high-resolution magnetic resonance images. Depressive symptoms were assessed using the Patient Health Questionnaire. Even after controlling for demographic and other confounding factors, having the MetS and meeting more MetS criteria covaried with reduced globus pallidus volume. Meeting more MetS criteria and reduced pallidal volume were also related to depressive symptoms. Moreover, the MetS-depression association was statistically mediated by pallidal volume. In summary, reduced globus pallidus volume is a neural correlate of the MetS that may partly account for its association with depressive symptoms. PMID:24096008

Onyewuenyi, Ikechukwu C.; Muldoon, Matthew F.; Christie, Israel C.; Erickson, Kirk I.; Gianaros, Peter J.

2014-01-01

42

The role of basal ganglia-forebrain circuitry in the vocal learning of songbirds  

E-print Network

The basal ganglia form the largest sub-cortical structure in the human brain and are implicated in numerous human diseases. In songbirds, as in mammals, basal ganglia-forebrain circuits are necessary for the learning and ...

Andalman, Aaron Samuel

2009-01-01

43

Functional Coupling Between Substantia Nigra and Basal Ganglia Homologues in Amphibians  

E-print Network

Functional Coupling Between Substantia Nigra and Basal Ganglia Homologues in Amphibians Kim L. Hoke the existence of a homologue of the mam- malian substantia nigra­basal ganglia circuit in the amphibian brain proposed that homologous basal ganglia circuits may exist in both amphibians and mammals (reviewed

Ryan, Michael J.

44

Basal ganglia function, stuttering, sequencing, and repair in adult songbirds.  

PubMed

A pallial-basal-ganglia-thalamic-pallial loop in songbirds is involved in vocal motor learning. Damage to its basal ganglia part, Area X, in adult zebra finches has been noted to have no strong effects on song and its function is unclear. Here we report that neurotoxic damage to adult Area X induced changes in singing tempo and global syllable sequencing in all animals, and considerably increased syllable repetition in birds whose song motifs ended with minor repetitions before lesioning. This stuttering-like behavior started at one month, and improved over six months. Unexpectedly, the lesioned region showed considerable recovery, including immigration of newly generated or repaired neurons that became active during singing. The timing of the recovery and stuttering suggest that immature recovering activity of the circuit might be associated with stuttering. These findings indicate that even after juvenile learning is complete, the adult striatum plays a role in higher level organization of learned vocalizations. PMID:25307086

Kubikova, Lubica; Bosikova, Eva; Cvikova, Martina; Lukacova, Kristina; Scharff, Constance; Jarvis, Erich D

2014-01-01

45

Cerebellar networks with the cerebral cortex and basal ganglia  

PubMed Central

The dominant view of cerebellar function has been that it is exclusively concerned with motor control and coordination. Recent results from neuroanatomical, behavioral and imaging studies have profoundly changed this view. Neuroanatomical studies using virus transneuronal tracers have demonstrated that the output from the cerebellum reaches vast areas of the neocortex, including regions of prefrontal and posterior parietal cortex. Furthermore, it has recently become clear that the cerebellum is reciprocally connected with the basal ganglia, indicating that the two subcortical structures are part of a densely interconnected network. Altogether, these results provide the neuroanatomical substrate for cerebellar involvement in non-motor functions mediated by the prefrontal and posterior parietal cortex, as well as in processes traditionally associated with the basal ganglia. PMID:23579055

Bostan, Andreea C.; Dum, Richard P.; Strick, Peter L.

2013-01-01

46

Morphological elucidation of basal ganglia circuits contributing reward prediction  

PubMed Central

Electrophysiological studies in monkeys have shown that dopaminergic neurons respond to the reward prediction error. In addition, striatal neurons alter their responsiveness to cortical or thalamic inputs in response to the dopamine signal, via the mechanism of dopamine-regulated synaptic plasticity. These findings have led to the hypothesis that the striatum exhibits synaptic plasticity under the influence of the reward prediction error and conduct reinforcement learning throughout the basal ganglia circuits. The reinforcement learning model is useful; however, the mechanism by which such a process emerges in the basal ganglia needs to be anatomically explained. The actor–critic model has been previously proposed and extended by the existence of role sharing within the striatum, focusing on the striosome/matrix compartments. However, this hypothesis has been difficult to confirm morphologically, partly because of the complex structure of the striosome/matrix compartments. Here, we review recent morphological studies that elucidate the input/output organization of the striatal compartments.

Fujiyama, Fumino; Takahashi, Susumu; Karube, Fuyuki

2015-01-01

47

Basal ganglia function, stuttering, sequencing, and repair in adult songbirds  

PubMed Central

A pallial-basal-ganglia-thalamic-pallial loop in songbirds is involved in vocal motor learning. Damage to its basal ganglia part, Area X, in adult zebra finches has been noted to have no strong effects on song and its function is unclear. Here we report that neurotoxic damage to adult Area X induced changes in singing tempo and global syllable sequencing in all animals, and considerably increased syllable repetition in birds whose song motifs ended with minor repetitions before lesioning. This stuttering-like behavior started at one month, and improved over six months. Unexpectedly, the lesioned region showed considerable recovery, including immigration of newly generated or repaired neurons that became active during singing. The timing of the recovery and stuttering suggest that immature recovering activity of the circuit might be associated with stuttering. These findings indicate that even after juvenile learning is complete, the adult striatum plays a role in higher level organization of learned vocalizations. PMID:25307086

Kubikova, Lubica; Bosikova, Eva; Cvikova, Martina; Lukacova, Kristina; Scharff, Constance; Jarvis, Erich D.

2014-01-01

48

A free-choice premium in the basal ganglia.  

PubMed

Apparently, the act of free choice confers value: when selecting between an item that you had previously chosen and an identical item that you had been forced to take, the former is often preferred. What could be the neural underpinnings of this free-choice bias in decision making? An elegant study recently published in Neuron suggests that enhanced reward learning in the basal ganglia may be the culprit. PMID:25282675

Niv, Yael; Langdon, Angela; Radulescu, Angela

2015-01-01

49

Asymptomatic moyamoya syndrome, atlantoaxial subluxation and basal ganglia calcification in a child with Down syndrome.  

PubMed

Down syndrome, the most common chromosomal abnormality, may be associated with various neurologic complications such as moyamoya syndrome, cervical spinal cord compression due to atlantoaxial subluxation, and basal ganglia damage, as well as epileptic seizures and stroke. Many cases of Down syndrome accompanied by isolated neurologic manifestations have been reported in children; however, Down syndrome with multiple neurologic conditions is rare. Here, we have reported a case of Down syndrome in a 10-year-old girl who presented with asymptomatic moyamoya syndrome, atlantoaxial subluxation with spinal cord compression, and basal ganglia calcification. To the best of our knowledge, this is the first report of Down syndrome, in a child, which was accompanied by these 3 neurologic complications simultaneously. As seen in this case, patients with Down syndrome may have neurologic conditions without any obvious neurologic symptoms; hence, patients with Down syndrome should be carefully examined for the presence of neurologic conditions. PMID:24416050

Lee, Kyung Yeon; Lee, Kun-Soo; Weon, Young Cheol

2013-12-01

50

Functional anatomy of the basal ganglia in X-linked recessive dystonia-parkinsonism.  

PubMed

Dystonia is a neurological syndrome characterized by sustained muscle contractions that produce repetitive twisting movements or abnormal postures. X-linked recessive dystonia parkinsonism (XDP; DYT3; Lubag) is an adult-onset disorder that manifests severe and progressive dystonia with a high frequency of generalization. In search for the anatomical basis for dystonia, we performed postmortem analyses of the functional anatomy of the basal ganglia based on the striatal compartments (ie, the striosomes and the matrix compartment) in XDP. Here, we provide anatomopathological evidence that, in the XDP neostriatum, the matrix compartment is relatively spared in a unique fashion, whereas the striosomes are severely depleted. We also document that there is a differential loss of striatal neuron subclasses in XDP. In view of the three-pathway basal ganglia model, we postulate that the disproportionate involvement of neostriatal compartments and their efferent projections may underlie the manifestation of dystonia in patients with XDP. This study is the first to our knowledge to show specific basal ganglia pathology that could explain the genesis of dystonia in human heredodegenerative movement disorders, suggesting that dystonia may result from an imbalance in the activity between the striosomal and matrix-based pathways. PMID:15912496

Goto, Satoshi; Lee, Lillian V; Munoz, Edwin L; Tooyama, Ikuo; Tamiya, Gen; Makino, Satoshi; Ando, Satoshi; Dantes, Marita B; Yamada, Kazumichi; Matsumoto, Sadayuki; Shimazu, Hideki; Kuratsu, Jun-ichi; Hirano, Asao; Kaji, Ryuji

2005-07-01

51

A selective role for right insula—basal ganglia circuits in appetitive stimulus processing  

PubMed Central

Hemispheric lateralization of hedonic evaluation (‘liking’) and incentive motivation (‘wanting’) in neural networks connecting the basal ganglia and insula (BG-I) in humans was examined. Participants with brain damage restricted to the BG-I of the right (n = 5) or left (n = 5) hemisphere, and 26 healthy participants matched on age, sex and intelligence quotient were tested on positively and negatively valenced pictures drawn from varied stimulus categories (Vijayaraghavan et al., 2008). Liking was assessed with explicit ratings of pleasantness using a nine-point Likert scale. Wanting was quantified as the amount of work (via repeated keypresses) that participants expended to increase (approach) or decrease (withdraw) viewing time. Right-lesion patients showed abnormally low viewing times and liking ratings for positive images. For a subset of positive images depicting sexual content, right-lesion patients exhibited active withdrawal, while the other two groups approached such stimuli. These results suggest that the right basal ganglia–insula complex plays a greater role than the left in supporting hedonic evaluation and motivational approach to positively valenced stimuli. The finding that active avoidance of stimuli that were not ‘liked’ was spared in both right- and left-sided lesion subjects suggests that unilateral damage to insula/basal ganglia circuits may not be sufficient to affect general incentive motivation independent of preference. PMID:22798397

Vijayaraghavan, Lavanya; Adolphs, Ralph; Kennedy, Daniel P.; Cassell, Martin; Tranel, Daniel; Paradiso, Sergio

2013-01-01

52

Bidirectional Control of Absence Seizures by the Basal Ganglia: A Computational Evidence  

PubMed Central

Absence epilepsy is believed to be associated with the abnormal interactions between the cerebral cortex and thalamus. Besides the direct coupling, anatomical evidence indicates that the cerebral cortex and thalamus also communicate indirectly through an important intermediate bridge–basal ganglia. It has been thus postulated that the basal ganglia might play key roles in the modulation of absence seizures, but the relevant biophysical mechanisms are still not completely established. Using a biophysically based model, we demonstrate here that the typical absence seizure activities can be controlled and modulated by the direct GABAergic projections from the substantia nigra pars reticulata (SNr) to either the thalamic reticular nucleus (TRN) or the specific relay nuclei (SRN) of thalamus, through different biophysical mechanisms. Under certain conditions, these two types of seizure control are observed to coexist in the same network. More importantly, due to the competition between the inhibitory SNr-TRN and SNr-SRN pathways, we find that both decreasing and increasing the activation of SNr neurons from the normal level may considerably suppress the generation of spike-and-slow wave discharges in the coexistence region. Overall, these results highlight the bidirectional functional roles of basal ganglia in controlling and modulating absence seizures, and might provide novel insights into the therapeutic treatments of this brain disorder. PMID:24626189

Wang, Tiebin; Jing, Wei; Xia, Yang; Xu, Peng; Luo, Cheng; Valdes-Sosa, Pedro A.; Yao, Dezhong

2014-01-01

53

Basal ganglia efferents to the brainstem centers controlling postural muscle tone and locomotion: a new concept for understanding motor disorders in basal ganglia dysfunction.  

PubMed

The present study is designed to elucidate how basal ganglia afferents from the substantia nigra pars reticulata (SNr) to the mesopontine tegmental area of the brainstem contribute to gait control and muscle-tone regulation. We used unanesthetized and acutely decerebrated cats (n=27) in which the striatum, thalamus and cerebral cortex were removed but the SNr was preserved. Repetitive stimulation (50 Hz, 10-60 microA, for 5-20 s) applied to a mesencephalic locomotor region (MLR), which corresponded to the cuneiform nucleus, and adjacent areas, evoked locomotor movements. On the other hand, stimulation of a muscle-tone inhibitory region in the pedunculopontine tegmental nucleus (PPN) suppressed postural muscle tone. An injection of either glutamatergic agonists (N-methyl-D-aspartic acid and kainic acid) or GABA antagonists (bicuculline and picrotoxin) into the MLR and PPN also induced locomotion and muscle-tone suppression, respectively. Repetitive electrical stimuli (50-100 Hz, 20-60 microA for 5-20 s) delivered to the SNr alone did not alter muscular activity. However stimulating the lateral part of the SNr attenuated and blocked PPN-induced muscle-tone suppression. Moreover, weaker stimulation of the medial part of the SNr reduced the number of step cycles and disturbed the rhythmic alternation of limb movements of MLR-induced locomotion. The onset of locomotion was delayed as the stimulus intensity was increased. At a higher strength SNr stimulation abolished the locomotion. An injection of bicuculline into either the PPN or the MLR diminished the SNr effects noted above. These results suggest that locomotion and postural muscle tone are subject to modulation by GABAergic nigrotegmental projections which have a partial functional topography: a lateral and medial SNr, for regulation of postural muscle tone and locomotion, respectively. We conclude that disorders of the basal ganglia may include dysfunction of the nigrotegmental (basal ganglia-brainstem) systems, which consequently leads to the production of abnormal muscle tone and gait disturbance. PMID:12763089

Takakusaki, K; Habaguchi, T; Ohtinata-Sugimoto, J; Saitoh, K; Sakamoto, T

2003-01-01

54

Familial idiopathic basal ganglia calcification (Fahr's disease) without neurological, cognitive and psychiatric symptoms is not linked to the IBGC1 locus on chromosome 14q  

Microsoft Academic Search

Idiopathic basal ganglia calcification (IBGC) is characterised by radiological, neurological, cognitive and psychiatric abnormalities. The associations between these abnormal phenotypes and abnormal genes remain unclear despite the recent mapping to chromosome 14q of a susceptibility locus for IBGC (IBGC1). We identified two siblings, from a large multigenerational pedigree, who had both been diagnosed with radiological IBGC, dementia, bipolar affective disorder

Henry Brodaty; Philip Mitchell; Georgina Luscombe; John B. J. Kwok; Renee F. Badenhop; Rod McKenzie; Peter R. Schofield

2002-01-01

55

http://www.tutis.ca/NeuroMD/index.htm 23 March 2013 Cerebellum and Basal Ganglia  

E-print Network

..................................................................................4 Basic Circuit........................................................................................................................4 Parallel and climbing fiber input has a very different effect on Purkinje cells...........................................................................................................................16 The circuit of the basal ganglia

Vilis, Tutis

56

Basal Ganglia MR Relaxometry in Obsessive-Compulsive Disorder: T2 Depends Upon Age of Symptom Onset  

Microsoft Academic Search

Dysfunction in circuits linking frontal cortex and basal ganglia (BG) is strongly implicated in obsessive-compulsive disorder\\u000a (OCD). On MRI studies, neuropsychiatric disorders with known BG pathology have abnormally short T2 relaxation values (a putative\\u000a biomarker of elevated iron) in this region. We asked if BG T2 values are abnormal in OCD. We measured volume and T2 and T1\\u000a relaxation rates

Stephen Correia; Emily Hubbard; Jason Hassenstab; Agustin Yip; Josef Vymazal; Vit Herynek; Jay Giedd; Dennis L. Murphy; Benjamin D. Greenberg

2010-01-01

57

Familial idiopathic basal ganglia calcification (Fahr`s disease).  

PubMed

Familial idiopathic basal ganglia calcification (Fahr`s disease) is a rare neurodegenerative disorder characterized by symmetrical and bilateral calcification of the basal ganglia. Calcifications may also occur in other brain regions such as dentate nucleus, thalamus, and cerebral cortex. Both familial and non-familial cases of Fahr`s disease have been reported, predominantly with autosomal-dominant fashion. The disease has a wide range of clinical presentations, predominantly with neuropsychiatric features and movement disorders. Psychiatric features reported in the literature include: cognitive impairment, depression, hallucinations, delusions, manic symptoms, anxiety, schizophrenia-like psychosis, and personality change. Other clinical features include: Parkinsonism, ataxia, headache, seizures, vertigo, stroke-like events, orthostatic hypotension, tremor, dysarthria, and paresis. Fahr`s disease should be considered in the differential diagnosis of psychiatric symptoms, particularly when associated with movement disorder. The disease should be differentiated from other conditions that can cause intracranial calcification. No specific treatment is currently available. Further research is needed to bridge the gap existing in our current knowledge of the prevalence, etiology, symptoms, and treatment of Fahr`s disease. PMID:24983277

Mufaddel, Amir A; Al-Hassani, Ghanem A

2014-07-01

58

Saccade learning with concurrent cortical and subcortical basal ganglia loops  

PubMed Central

The Basal Ganglia (BG) is a central structure involved in multiple cortical and subcortical loops. Some of these loops are believed to be responsible for saccade target selection. We study here how the very specific structural relationships of these saccadic loops can affect the ability of learning spatial and feature-based tasks. We propose a model of saccade generation with reinforcement learning capabilities based on our previous BG and superior colliculus models. It is structured around the interactions of two parallel cortico-basal loops and one tecto-basal loop. The two cortical loops separately deal with spatial and non-spatial information to select targets in a concurrent way. The subcortical loop is used to make the final target selection leading to the production of the saccade. These different loops may work in concert or disturb each other regarding reward maximization. Interactions between these loops and their learning capabilities are tested on different saccade tasks. The results show the ability of this model to correctly learn basic target selection based on different criteria (spatial or not). Moreover the model reproduces and explains training dependent express saccades toward targets based on a spatial criterion. Finally, the model predicts that in absence of prefrontal control, the spatial loop should dominate. PMID:24795615

N'Guyen, Steve; Thurat, Charles; Girard, Benoît

2014-01-01

59

Changing Views of Basal Ganglia Circuits and Circuit Disorders  

PubMed Central

The basal ganglia (BG) have long been considered to play an important role in the control of movement and the pathophysiology of movement disorders, such as Parkinson’s disease (PD). Studies over the past decades have considerably broadened this view, indicating that the BG participate in multiple, parallel, largely segregated, cortico-subcortical reentrant pathways involving motor, associative and limbic functions. Research has shown that dysfunction within individual circuits is associated not only with movement disorders, but also with neuropsychiatric disorders. Accordingly, a number of movement disorders and neuropsychiatric disorders such as obsessive compulsive disorder and Tourette’s syndrome are viewed as “circuit disorders.” We here discuss the changes in our current understanding of the anatomic and functional organization of BG circuits and related circuit disorders. PMID:20521487

DeLong, Mahlon; Wichmann, Thomas

2014-01-01

60

Basal ganglia output to the thalamus: still a paradox  

PubMed Central

The basal ganglia (BG) recipient thalamus controls motor output but it remains unclear how its activity is regulated. Several studies report that thalamic activation occurs via disinhibition during pauses in the firing of inhibitory pallidal inputs from the BG. Other studies indicate that thalamic spiking is triggered by pallidal inputs via post-inhibitory ‘rebound’ calcium spikes. Finally excitatory cortical inputs can drive thalamic activity, which becomes entrained, or time-locked, to pallidal spikes. We present a unifying framework where these seemingly distinct results arise from a continuum of thalamic firing ‘modes’ controlled by excitatory inputs. We provide a mechanistic explanation for paradoxical pallidothalamic coactivations observed during behavior and raise new questions of what information is integrated in the thalamus to control behavior. PMID:24188636

Farries, Michael A.; Fee, Michale S.

2013-01-01

61

What are the computations of the cerebellum, the basal ganglia and the cerebral cortex?  

Microsoft Academic Search

The classical notion that the cerebellum and the basal ganglia are dedicated to motor control is under dispute given increasing evidence of their involvement in non-motor functions. Is it then impossible to characterize the functions of the cerebellum, the basal ganglia and the cerebral cortex in a simplistic manner? This paper presents a novel view that their computational roles can

Kenji Doya

1999-01-01

62

Distinct Hippocampal and Basal Ganglia Contributions to Probabilistic Learning and Reversal  

ERIC Educational Resources Information Center

The hippocampus and the basal ganglia are thought to play fundamental and distinct roles in learning and memory, supporting two dissociable memory systems. Interestingly, however, the hippocampus and the basal ganglia have each, separately, been implicated as necessary for reversal learning--the ability to adaptively change a response when…

Shohamy, Daphna; Myers, Catherine E.; Hopkins, Ramona O.; Sage, Jake; Gluck, Mark A.

2009-01-01

63

Stepping out of the box: information processing in the neural networks of the basal ganglia  

Microsoft Academic Search

The Albin-DeLong ‘box and arrow’ model has long been the accepted standard model for the basal ganglia network. However, advances in physiological and anatomical research have enabled a more detailed neural network approach. Recent computational models hold that the basal ganglia use reinforcement signals and local competitive learning rules to reduce the dimensionality of sparse cortical information. These models predict

Izhar Bar-Gad; Hagai Bergman

2001-01-01

64

Information processing, dimensionality reduction and reinforcement learning in the basal ganglia  

Microsoft Academic Search

Modeling of the basal ganglia has played a major role in our understanding of this elusive group of nuclei. Models of the basal ganglia have undergone evolutionary and revolutionary changes over the last 20 years, as new research in the fields of anatomy, physiology and biochemistry of these nuclei has yielded new information. Early models dealt with a single pathway

Izhar Bar-Gad; Genela Morris; Hagai Bergman

2003-01-01

65

Regulation of parkinsonian motor behaviours by optogenetic control of basal ganglia circuitry  

Microsoft Academic Search

Neural circuits of the basal ganglia are critical for motor planning and action selection. Two parallel basal ganglia pathways have been described, and have been proposed to exert opposing influences on motor function. According to this classical model, activation of the `direct' pathway facilitates movement and activation of the `indirect' pathway inhibits movement. However, more recent anatomical and functional evidence

Alexxai V. Kravitz; Benjamin S. Freeze; Philip R. L. Parker; Kenneth Kay; Myo T. Thwin; Karl Deisseroth; Anatol C. Kreitzer

2010-01-01

66

Regulation of parkinsonian motor behaviours by optogenetic control of basal ganglia circuitry  

E-print Network

LETTERS Regulation of parkinsonian motor behaviours by optogenetic control of basal ganglia of basal ganglia circuitry in vivo, using optogenetic control11­14 of direct- and indirect-pathway medium motor deficits. To obtain selective optogenetic control of the direct and indirect pathways in vivo, we

Schnitzer, Mark

67

Actor critic models of the basal ganglia: new anatomical and computational perspectives  

Microsoft Academic Search

A large number of computational models of information processing in the basal ganglia have been developed in recent years. Prominent in these are actor- critic models of basal ganglia functioning, which build on the strong resemblance between dopamine neuron activity and the temporal difference prediction error signal in the critic, and between dopamine-dependent long-term synaptic plasticity in the striatum and

Daphna Joel; Yael Niv; Eytan Ruppin

68

Temporal dynamics of basal ganglia response and connectivity during verbal working memory  

Microsoft Academic Search

Research on the neural basis of working memory (WM) has generally focused on neocortical regions; comparatively little is known about the role of subcortical structures. There is growing evidence that the basal ganglia are involved in WM, but their contribution to different component processes of WM is poorly understood. We examined the temporal dynamics of basal ganglia response and connectivity

Catherine Chang; Sonia Crottaz-Herbette; Vinod Menonb

69

Basal Ganglia MR Relaxometry in Obsessive-Compulsive Disorder: T2 Depends Upon Age of Symptom Onset  

PubMed Central

Dysfunction in circuits linking frontal cortex and basal ganglia (BG) is strongly implicated in obsessive-compulsive disorder (OCD). On MRI studies, neuropsychiatric disorders with known BG pathology have abnormally short T2 relaxation values (a putative biomarker of elevated iron) in this region. We asked if BG T2 values are abnormal in OCD. We measured volume and T2 and T1 relaxation rates in BG of 32 adults with OCD and 33 matched controls. There were no group differences in volume or T1 values in caudate, putamen, or globus pallidus (GP). The OCD group had lower T2 values (suggesting higher iron content) in the right GP, with a trend in the same direction for the left GP. This effect was driven by patients whose OCD symptoms began from around adolescence to early adulthood. The results suggest a possible relationship between age of OCD onset and iron deposition in the basal ganglia. PMID:20503112

Hubbard, Emily; Hassenstab, Jason; Yip, Agustin; Vymazal, Josef; Herynek, Vit; Giedd, Jay; Murphy, Dennis L.; Greenberg, Benjamin D.

2010-01-01

70

Laterality, somatotopy and reproducibility of the basal ganglia and motor cortex during motor tasks.  

PubMed

We investigated the basal ganglia, motor cortex area 4, and supplementary motor area (SMA) using functional magnetic resonance imaging (fMRI) and five motor tasks: switching between finger and toe movements, writing, finger tapping, pronation/supination, and saccadic eye movements. We found reliable activation in the caudate nucleus and putamen in single subjects without the need for inter-subject averaging. Percent signal changes in basal ganglia were smaller by a factor of three than those in SMA or motor cortex (1% vs. 2.5-3%). There was a definite foot-dorsal, hand-ventral basal ganglia somatotopy, similar to prior data from primates. Saccadic eye movements activated the caudate nucleus significantly more than the other tasks did. Unilateral movements produced bilateral activation in the striatum even when motor cortex activation was unilateral. Surprisingly, bilateral performance of the tasks led, on average, to consistently smaller basal ganglia activation than did unilateral performance (P<0.001), suggesting less inhibition of contralateral movements during bilateral tasks. Moreover, there was a striking dominance pattern in basal ganglia motor activation: the left basal ganglia were more active than the right for right handers, regardless of the hand used. This lateralization appears much stronger than that previously reported for motor cortex. Comparisons of inter-subject and intra-subject reproducibility indicated a much larger variability in basal ganglia and SMA compared to motor cortex, in spite of similar percent signal changes in the latter two structures. PMID:11011024

Scholz, V H; Flaherty, A W; Kraft, E; Keltner, J R; Kwong, K K; Chen, Y I; Rosen, B R; Jenkins, B G

2000-10-01

71

A case of idiopathic basal ganglia calcification associated with membranoproliferative glomerulonephritis.  

PubMed

Idiopathic basal ganglia calcification (IBGC) is a syndrome in which bilateral cerebral calcification occurs despite the absence of abnormal calcium metabolism. A 17-year-old Japanese female was admitted for investigation of intermittent proteinuria from the age of 12 years. On admission, her blood pressure was 126/60 mmHg and her serum creatinine was 0.8 mg/dL. Although computed tomography revealed bilateral striopallidodentate calcinosis, her level of intelligence and neurological findings were normal, as were the results of endocrine tests including parathyroid hormone. Asymptomatic IBGC was diagnosed. Renal biopsy showed membranoproliferative glomerulonephritis. Peritoneal dialysis was started for end-stage renal failure when she was 24 years old. Pyramidal and extrapyramidal signs started to develop at the age of 27 years and progressed, resulting in death from aspiration pneumonia at the age of 32 years. Post-mortem revealed bilateral calcification of the basal ganglia, dentate nucleus, thalamus, and centrum semiovale. On light microscopy, there was circumferential calcification of the media and intima of affected vessels in the brain, including small arteries, small veins, and capillaries, and luminal narrowing was seen. On electron microscopy, layers of differing electron density were arranged in concentric laminae. This is the first report of IBGC with bilateral and symmetrical cerebral calcification accompanied by membranoproliferative glomerulonephritis resulting in end-stage renal failure. PMID:22001464

Tsuchiya, Yoshiki; Ubara, Yoshifumi; Anzai, Makoto; Hiramatsu, Rikako; Suwabe, Tatsuya; Hoshino, Junichi; Sumida, Keiichi; Hasegawa, Eiko; Yamanouchi, Masayuki; Hayami, Noriko; Marui, Yuji; Sawa, Naoki; Hara, Shigeko; Takaichi, Kenmei; Oohashi, Kenichi

2011-01-01

72

Genetic screening and functional characterization of PDGFRB mutations associated with basal ganglia calcification of unknown etiology.  

PubMed

Three causal genes for idiopathic basal ganglia calcification (IBGC) have been identified. Most recently, mutations in PDGFRB, encoding a member of the platelet-derived growth factor receptor family type ?, and PDGFB, encoding PDGF-B, the specific ligand of PDGFR?, were found implicating the PDGF-B/PDGFR? pathway in abnormal brain calcification. In this study, we aimed to identify and study mutations in PDGFRB and PDGFB in a series of 26 patients from the Mayo Clinic Florida Brain Bank with moderate to severe basal ganglia calcification (BCG) of unknown etiology. No mutations in PDGFB were found. However, we identified one mutation in PDGFRB, p.R695C located in the tyrosine kinase domain, in one BGC patient. We further studied the function of p.R695C mutant PDGFR? and two previously reported mutants, p.L658P and p.R987W PDGFR? in cell culture. We show that, in response to PDGF-BB stimulation, the p.L658P mutation completely suppresses PDGFR? autophosphorylation, whereas the p.R695C mutation results in partial loss of autophosphorylation. For the p.R987W mutation, our data suggest a different mechanism involving reduced protein levels. These genetic and functional studies provide the first insight into the pathogenic mechanisms associated with PDGFRB mutations and provide further support for a pathogenic role of PDGFRB mutations in BGC. PMID:24796542

Sanchez-Contreras, Monica; Baker, Matthew C; Finch, NiCole A; Nicholson, Alexandra; Wojtas, Aleksandra; Wszolek, Zbigniew K; Ross, Owen A; Dickson, Dennis W; Rademakers, Rosa

2014-08-01

73

Role of the basal ganglia in switching a planned response.  

PubMed

The ability to perform an appropriate response in the presence of competing alternatives is a critical facet of human behavioral control. This is especially important if a response is prepared for execution but then has to be changed suddenly. A popular hypothesis of basal ganglia (BG) function suggests that its direct and indirect pathways could provide a neural mechanism to rapidly switch from one planned response to an alternative. However, if one response is more dominant or 'automatic' than the other, the BG might have a different role depending on switch direction. We built upon the pro- and antisaccade tasks, two models of automatic and voluntary behavior, respectively, and investigated whether the BG are important for switching any planned response in general, or if they are more important for switching from a more automatic response to a response that is more difficult to perform. Subjects prepared either a pro- or antisaccade but then had to switch it unexpectedly on a subset of trials. The results revealed increased striatal activation for switching from a pro- to an antisaccade but this did not occur for switching from an anti- to a prosaccade. This activation pattern depended on the relative difficulty in switching, and it was distinct from frontal eye fields, an area shown to be more active for antisaccade trials than for prosaccade trials. This suggests that the BG are important for compensating for differences in response difficulty, facilitating the rapid switching of one response for another. PMID:19508693

Cameron, Ian G M; Coe, Brian C; Watanabe, Masayuki; Stroman, Patrick W; Munoz, Douglas P

2009-06-01

74

Origins of basal ganglia output signals in singing juvenile birds.  

PubMed

Across species, complex circuits inside the basal ganglia (BG) converge on pallidal output neurons that exhibit movement-locked firing patterns. Yet the origins of these firing patterns remain poorly understood. In songbirds during vocal babbling, BG output neurons homologous to those found in the primate internal pallidal segment are uniformly activated in the tens of milliseconds prior to syllable onsets. To test the origins of this remarkably homogenous BG output signal, we recorded from diverse upstream BG cell types during babbling. Prior to syllable onsets, at the same time that internal pallidal segment-like neurons were activated, putative medium spiny neurons, fast spiking and tonically active interneurons also exhibited transient rate increases. In contrast, pallidal neurons homologous to those found in primate external pallidal segment exhibited transient rate decreases. To test origins of these signals, we performed recordings following lesion of corticostriatal inputs from premotor nucleus HVC. HVC lesions largely abolished these syllable-locked signals. Altogether, these findings indicate a striking homogeneity of syllable timing signals in the songbird BG during babbling and are consistent with a role for the indirect and hyperdirect pathways in transforming cortical inputs into BG outputs during an exploratory behavior. PMID:25392171

Pidoux, Morgane; Bollu, Tejapratap; Riccelli, Tori; Goldberg, Jesse H

2015-02-01

75

Basal Ganglia Outputs Map Instantaneous Position Coordinates during Behavior.  

PubMed

The basal ganglia (BG) are implicated in many movement disorders, yet how they contribute to movement remains unclear. Using wireless in vivo recording, we measured BG output from the substantia nigra pars reticulata (SNr) in mice while monitoring their movements with video tracking. The firing rate of most nigral neurons reflected Cartesian coordinates (either x- or y-coordinates) of the animal's head position during movement. The firing rates of SNr neurons are either positively or negatively correlated with the coordinates. Using an egocentric reference frame, four types of neurons can be classified: each type increases firing during movement in a particular direction (left, right, up, down), and decreases firing during movement in the opposite direction. Given the high correlation between the firing rate and the x and y components of the position vector, the movement trajectory can be reconstructed from neural activity. Our results therefore demonstrate a quantitative and continuous relationship between BG output and behavior. Thus, a steady BG output signal from the SNr (i.e., constant firing rate) is associated with the lack of overt movement, when a stable posture is maintained by structures downstream of the BG. Any change in SNr firing rate is associated with a change in position (i.e., movement). We hypothesize that the SNr output quantitatively determines the direction, velocity, and amplitude of voluntary movements. By changing the reference signals to downstream position control systems, the BG can produce transitions in body configurations and initiate actions. PMID:25673860

Barter, Joseph W; Li, Suellen; Sukharnikova, Tatyana; Rossi, Mark A; Bartholomew, Ryan A; Yin, Henry H

2015-02-11

76

Task-rest modulation of basal ganglia connectivity in mild to moderate Parkinson's disease.  

PubMed

Parkinson's disease (PD) is associated with abnormal synchronization in basal ganglia-thalamo-cortical loops. We tested whether early PD patients without demonstrable cognitive impairment exhibit abnormal modulation of functional connectivity at rest, while engaged in a task, or both. PD and healthy controls underwent two functional MRI scans: a resting-state scan and a Stroop Match-to-Sample task scan. Rest-task modulation of basal ganglia (BG) connectivity was tested using seed-to-voxel connectivity analysis with task and rest time series as conditions. Despite substantial overlap of BG-cortical connectivity patterns in both groups, connectivity differences between groups had clinical and behavioral correlates. During rest, stronger putamen-medial parietal and pallidum-occipital connectivity in PD than controls was associated with worse task performance and more severe PD symptoms suggesting that abnormalities in resting-state connectivity denote neural network dedifferentiation. During the executive task, PD patients showed weaker BG-cortical connectivity than controls, i.e., between caudate-supramarginal gyrus and pallidum-inferior prefrontal regions, that was related to more severe PD symptoms and worse task performance. Yet, task processing also evoked stronger striatal-cortical connectivity, specifically between caudate-prefrontal, caudate-precuneus, and putamen-motor/premotor regions in PD relative to controls, which was related to less severe PD symptoms and better performance on the Stroop task. Thus, stronger task-evoked striatal connectivity in PD demonstrated compensatory neural network enhancement to meet task demands and improve performance levels. fMRI-based network analysis revealed that despite resting-state BG network compromise in PD, BG connectivity to prefrontal, premotor, and precuneus regions can be adequately invoked during executive control demands enabling near normal task performance. PMID:25280970

Müller-Oehring, Eva M; Sullivan, Edith V; Pfefferbaum, Adolf; Huang, Neng C; Poston, Kathleen L; Bronte-Stewart, Helen M; Schulte, Tilman

2014-10-01

77

The involvement of the primate frontal cortex-basal ganglia system in arbitrary visuomotor association learning  

E-print Network

It is the goal of this thesis to examine the frontal cortex-basal ganglia system during arbitrary visuomotor association learning, the forming of arbitrary links between visual stimuli and motor responses (e.g. red means ...

Machon, Michelle S

2009-01-01

78

A Case Report of Basal Ganglia Calcification - A Rare Finding of Hypoparathyroidism  

PubMed Central

Physiological intracranial calcification occurs in about 0.3-1.5% of cases. It is asymptomatic and detected incidentally by neuroimaging. Pathological basal ganglia calcification is due to various causes, such as: metabolic disorders, infectious and genetic diseases. Hypoparathyroidism and pseudohypoparathyroidism are the most common causes of pathological basal ganglia calcification. Besides tetany and seizures this condition is presented by parkinsonism and dementia. Such parkinsonism does not respond to drugs containing levodopa. Infections (toxoplasmosis, rubella, cytomegalovirus, cysticercosis, AIDS) give multiple and asymmetric intracranial calcification. Inherited and neurodegenerative diseases cause symmetrical, bilateral basal ganglia calcification which is not related to metabolic disorders. Since adequate treatment of hypoparathyroidism may lead to marked clinical improvement, serum concentration of calcium, phosphorus, and parathyroid hormone (PTH) is suggested to be determined in all individuals with calcification of the basal ganglia to rule out hypoparathyroidism. PMID:22224190

Basak, Ramen C.

2009-01-01

79

Cytokine Effects on the Basal Ganglia and Dopamine Function: the Subcortical Source of Inflammatory Malaise  

PubMed Central

Data suggest that cytokines released during the inflammatory response target subcortical structures including the basal ganglia as well as dopamine function to acutely induce behavioral changes that support fighting infection and wound healing. However, chronic inflammation and exposure to inflammatory cytokines appears to lead to persisting alterations in the basal ganglia and dopamine function reflected by anhedonia, fatigue, and psychomotor slowing. Moreover, reduced neural responses to hedonic reward, decreased dopamine metabolites in the cerebrospinal fluid and increased presynaptic dopamine uptake and decreased turnover have been described. This multiplicity of changes in the basal ganglia and dopamine function suggest fundamental effects of inflammatory cytokines on dopamine synthesis, packaging, release and/or reuptake, which may sabotage and circumvent the efficacy of current treatment approaches. Thus, examination of the mechanisms by which cytokines alter the basal ganglia and dopamine function will yield novel insights into the treatment of cytokine-induced behavioral changes and inflammatory malaise. PMID:23000204

Felger, Jennifer C.; Miller, Andrew H.

2012-01-01

80

A basal ganglia-forebrain circuit in the songbird biases motor output to avoid vocal errors  

E-print Network

In songbirds, as in mammals, basal ganglia-forebrain circuits are necessary for the learning and production of complex motor behaviors; however, the precise role of these circuits remains unknown. It has recently been shown ...

Andalman, Aaron S.

81

Modeling the role of the basal ganglia in motor control and motor programming  

E-print Network

The basal ganglia (BG) are a group of highly interconnected nuclei buried deep in the brain. They are involved in an important range of brain functions, including both lower-level movement control and higher-level cognitive ...

Mao, Zhi-Hong, 1972-

2005-01-01

82

The basal ganglia within a cognitive system in birds and mammals.  

PubMed

The primate basal ganglia are fundamental to Ackermann et al.'s proposal. However, primates and rodents are models for human cognitive functions involving basal ganglia circuits, and links between striatal function and vocal communication come from songbirds. We suggest that the proposal is better integrated in cognitive and/or motor theories on spoken language origins and with more analogous nonhuman animal models. PMID:25514958

Petkov, Christopher I; Jarvis, Erich D

2014-12-01

83

Basal ganglia volumetric studies in affective disorder: what did we learn in the last 15 years?  

Microsoft Academic Search

Summary.  Until today, morphometric neuroimaging studies on affective disorders concentrate on the limbic system, especially the hippocampus,\\u000a amygdala, and anterior cingulate. In most of the studies and reviews available today, the basal ganglia are of secondary interest.\\u000a It seems that the basal ganglia are interest of neurologist, whereas the limbic system is reserved for psychiatric neuroimaging\\u000a studies. We follow a different

R. M. Bonelli; H.-P. Kapfhammer; S. S. Pillay; D. A. Yurgelun-Todd

2006-01-01

84

Quantitation of the human basal ganglia with Positron Emission Tomography  

SciTech Connect

The accurate measurement of the concentration of a radioisotope in small structures with PET requires a correction for quantitation loss due to the partial volume effect and the effect of scattered radiation. To evaluate errors associated with measures in the human basal ganglia (BG) we have built a unilateral model of the BG that we have inserted in a 20 cm cylinder. The recovery coefficient (RC = measured activity/true activity) for our BG phantom has been measured on a CTI tomograph (model 931-08/12) with different background concentrations (contrast) and at different axial locations in the gantry. The BG was visualized on 4 or 5 slices depending on its position in the gantry and on the contrast used. The RC was 0.75 with no background (contrast equal to 1.0). Increasing the relative radioactivity concentration in the background increased the RC from 0.75 to 2.00 when the contrast was {minus}0.7 (BG < Background). The RC was also affected by the size and the shape of the region of interest (ROI) used (RC from 0.75 to 0.67 with ROI size from 0.12 to 1.41 cm{sup 2}). These results show that accurate RC correction depends not only on the volume of the structure but also on its contrast with its surroundings as well as on the selection of the ROI. They also demonstrate that the higher the contrast the more sensitive to axial positioning PET measurements in the BG are. These data provide us with some information about the variability of PET measurements in small structure like the BG and we have proposed some strategies to improve the reproducibility. 18 refs., 3 figs., 5 tabs.

Bendriem, B.; Dewey, S.L.; Schlyer, D.J.; Wolf, A.P.; Volkow, N.D.

1990-01-01

85

Localization and Function of GABA Transporters GAT-1 and GAT-3 in the Basal Ganglia  

PubMed Central

GABA transporter type 1 and 3 (GAT-1 and GAT-3, respectively) are the two main subtypes of GATs responsible for the regulation of extracellular GABA levels in the central nervous system. These transporters are widely expressed in neuronal (mainly GAT-1) and glial (mainly GAT-3) elements throughout the brain, but most data obtained so far relate to their role in the regulation of GABAA receptor-mediated postsynaptic tonic and phasic inhibition in the hippocampus, cerebral cortex and cerebellum. Taking into consideration the key role of GABAergic transmission within basal ganglia networks, and the importance for these systems to be properly balanced to mediate normal basal ganglia function, we analyzed in detail the localization and function of GAT-1 and GAT-3 in the globus pallidus of normal and Parkinsonian animals, in order to further understand the substrate and possible mechanisms by which GABA transporters may regulate basal ganglia outflow, and may become relevant targets for new therapeutic approaches for the treatment of basal ganglia-related disorders. In this review, we describe the general features of GATs in the basal ganglia, and give a detailed account of recent evidence that GAT-1 and GAT-3 regulation can have a major impact on the firing rate and pattern of basal ganglia neurons through pre- and post-synaptic GABAA- and GABAB-receptor-mediated effects. PMID:21847373

Jin, Xiao-Tao; Galvan, Adriana; Wichmann, Thomas; Smith, Yoland

2011-01-01

86

Automated segmentation of multifocal basal ganglia T2*-weighted MRI hypointensities  

PubMed Central

Multifocal basal ganglia T2*-weighted (T2*w) hypointensities, which are believed to arise mainly from vascular mineralization, were recently proposed as a novel MRI biomarker for small vessel disease and ageing. These T2*w hypointensities are typically segmented semi-automatically, which is time consuming, associated with a high intra-rater variability and low inter-rater agreement. To address these limitations, we developed a fully automated, unsupervised segmentation method for basal ganglia T2*w hypointensities. This method requires conventional, co-registered T2*w and T1-weighted (T1w) volumes, as well as region-of-interest (ROI) masks for the basal ganglia and adjacent internal capsule generated automatically from T1w MRI. The basal ganglia T2*w hypointensities were then segmented with thresholds derived with an adaptive outlier detection method from respective bivariate T2*w/T1w intensity distributions in each ROI. Artefacts were reduced by filtering connected components in the initial masks based on their standardised T2*w intensity variance. The segmentation method was validated using a custom-built phantom containing mineral deposit models, i.e. gel beads doped with 3 different contrast agents in 7 different concentrations, as well as with MRI data from 98 community-dwelling older subjects in their seventies with a wide range of basal ganglia T2*w hypointensities. The method produced basal ganglia T2*w hypointensity masks that were in substantial volumetric and spatial agreement with those generated by an experienced rater (Jaccard index = 0.62 ± 0.40). These promising results suggest that this method may have use in automatic segmentation of basal ganglia T2*w hypointensities in studies of small vessel disease and ageing. PMID:25451469

Glatz, Andreas; Bastin, Mark E.; Kiker, Alexander J.; Deary, Ian J.; Wardlaw, Joanna M.; Valdés Hernández, Maria C.

2015-01-01

87

Automated segmentation of multifocal basal ganglia T2*-weighted MRI hypointensities.  

PubMed

Multifocal basal ganglia T2*-weighted (T2*w) hypointensities, which are believed to arise mainly from vascular mineralization, were recently proposed as a novel MRI biomarker for small vessel disease and ageing. These T2*w hypointensities are typically segmented semi-automatically, which is time consuming, associated with a high intra-rater variability and low inter-rater agreement. To address these limitations, we developed a fully automated, unsupervised segmentation method for basal ganglia T2*w hypointensities. This method requires conventional, co-registered T2*w and T1-weighted (T1w) volumes, as well as region-of-interest (ROI) masks for the basal ganglia and adjacent internal capsule generated automatically from T1w MRI. The basal ganglia T2*w hypointensities were then segmented with thresholds derived with an adaptive outlier detection method from respective bivariate T2*w/T1w intensity distributions in each ROI. Artefacts were reduced by filtering connected components in the initial masks based on their standardised T2*w intensity variance. The segmentation method was validated using a custom-built phantom containing mineral deposit models, i.e. gel beads doped with 3 different contrast agents in 7 different concentrations, as well as with MRI data from 98 community-dwelling older subjects in their seventies with a wide range of basal ganglia T2*w hypointensities. The method produced basal ganglia T2*w hypointensity masks that were in substantial volumetric and spatial agreement with those generated by an experienced rater (Jaccard index=0.62±0.40). These promising results suggest that this method may have use in automatic segmentation of basal ganglia T2*w hypointensities in studies of small vessel disease and ageing. PMID:25451469

Glatz, Andreas; Bastin, Mark E; Kiker, Alexander J; Deary, Ian J; Wardlaw, Joanna M; Valdés Hernández, Maria C

2015-01-15

88

Exercise-induced changes in basal ganglia volume and cognition in older adults.  

PubMed

Physical activity has been demonstrated to diminish age-related brain volume shrinkage in several brain regions accompanied by a reduction of age-related decline in cognitive functions. Most studies investigated the impact of cardiovascular fitness or training. Other types of fitness or training are less well investigated. In addition, little is known about exercise effects on volume of the basal ganglia, which, however, are involved in motor activities and cognitive functioning. In the current study (1) we examined the relationships of individual cardiovascular and motor fitness levels with the volume of the basal ganglia (namely caudate, putamen, and globus pallidus) and selected cognitive functions (executive control, perceptual speed). (2) We investigated the effect of 12-month training interventions (cardiovascular and coordination training, control group stretching and relaxation) on the volume of the respective basal ganglia nuclei. Results revealed that motor fitness but not cardiovascular fitness was positively related with the volume of the putamen and the globus pallidus. Additionally, a moderating effect of the volume of the basal ganglia (as a whole, but also separately for putamen and globus pallidus) on the relationship between motor fitness and executive function was revealed. Coordination training increased caudate and globus pallidus volume. We provide evidence that coordinative exercise seems to be a favorable leisure activity for older adults that has the potential to improve volume of the basal ganglia. PMID:25255932

Niemann, C; Godde, B; Staudinger, U M; Voelcker-Rehage, C

2014-09-22

89

Oscillations in the basal ganglia under normal conditions and in movement disorders.  

PubMed

A substantial body of work within the last decade has demonstrated that there is a variety of oscillatory phenomena that occur in the basal ganglia and in associated regions of the thalamus and cortex. Most of the earlier studies focused on recordings in rodents and primates. More recently, significant advances have been made in this field of research through the analysis of basal ganglia field potentials recorded from implanted deep brain stimulation electrodes in the basal ganglia of human patients with Parkinson's disease and other disorders. It now appears that oscillatory activity may play a significant role in the pathogenesis of these diseases. The most significant finding is that in Parkinson's disease synchronized oscillatory activity in the 10- to 35-Hz band (often termed "beta-band") is prevalent in the basal ganglia-thalamocortical circuits, and that such activity can be reduced by dopaminergic treatments. The entrainment of large portions of these circuits may disrupt information processing in them and may lead to parkinsonian akinesia (and perhaps tremor). Although less firmly established than the role of oscillations in movement disorders, oscillatory activities at higher frequencies may also be a component of normal basal ganglia physiology. PMID:16830313

Gatev, Plamen; Darbin, Olivier; Wichmann, Thomas

2006-10-01

90

Do Basal Ganglia Amplify Willed Action by Stochastic Resonance? A Model  

PubMed Central

Basal ganglia are usually attributed a role in facilitating willed action, which is found to be impaired in Parkinson's disease, a pathology of basal ganglia. We hypothesize that basal ganglia possess the machinery to amplify will signals, presumably weak, by stochastic resonance. Recently we proposed a computational model of Parkinsonian reaching, in which the contributions from basal ganglia aid the motor cortex in learning to reach. The model was cast in reinforcement learning framework. We now show that the above basal ganglia computational model has all the ingredients of stochastic resonance process. In the proposed computational model, we consider the problem of moving an arm from a rest position to a target position: the two positions correspond to two extrema of the value function. A single kick (a half-wave of sinusoid, of sufficiently low amplitude) given to the system in resting position, succeeds in taking the system to the target position, with high probability, only at a critical noise level. But for suboptimal noise levels, the model arm's movements resemble Parkinsonian movement symptoms like akinetic rigidity (low noise) and dyskinesias (high noise). PMID:24302984

Chakravarthy, V. Srinivasa

2013-01-01

91

A review of pathologies associated with high T1W signal intensity in the basal ganglia on Magnetic Resonance Imaging  

PubMed Central

Summary With several functions and a fundamental influence over cognition and motor functions, the basal ganglia are the cohesive centre of the brain. There are several conditions which affect the basal ganglia and these have various clinical and radiological manifestations. Nevertheless, on magnetic resonance imaging there is a limited differential diagnosis for those conditions presenting with T1 weighted spin echo hyperintensity within the central nervous system in general and the basal ganglia in particular. The aim of our review is to explore some of these basal ganglia pathologies and provide image illustrations. PMID:24900164

Zaitout, Zahia; Romanowski, Charles; Karunasaagarar, Kavitasagary; Connolly, Daniel; Batty, Ruth

2014-01-01

92

Goal-directed and habitual control in the basal ganglia: implications for Parkinson’s disease  

PubMed Central

Progressive loss of the ascending dopaminergic projection in the basal ganglia is a fundamental pathological feature of Parkinson’s disease. Studies in animals and humans have identified spatially segregated functional territories in the basal ganglia for the control of goal-directed and habitual actions. In patients with Parkinson’s disease the loss of dopamine is predominantly in the posterior putamen, a region of the basal ganglia associated with the control of habitual behaviour. These patients may therefore be forced into a progressive reliance on the goal-directed mode of action control that is mediated by comparatively preserved processing in the rostromedial striatum. Thus, many of their behavioural difficulties may reflect a loss of normal automatic control owing to distorting output signals from habitual control circuits, which impede the expression of goal-directed action. PMID:20944662

Redgrave, Peter; Rodriguez, Manuel; Smith, Yoland; Rodriguez-Oroz, Maria C.; Lehericy, Stephane; Bergman, Hagai; Agid, Yves; DeLong, Mahlon R.; Obeso, Jose A.

2011-01-01

93

Hypofractionated Stereotactic Radiosurgery in a Large Bilateral Thalamic and Basal Ganglia Arteriovenous Malformation  

PubMed Central

Purpose. Arteriovenous malformations (AVMs) in the basal ganglia and thalamus have a more aggressive natural history with a higher morbidity and mortality than AVMs in other locations. Optimal treatment—complete obliteration without new neurological deficits—is often challenging. We present a patient with a large bilateral basal ganglia and thalamic AVM successfully treated with hypofractionated stereotactic radiosurgery (HFSRS) with intensity modulated radiotherapy (IMRT). Methods. The patient was treated with hypofractionated stereotactic radiosurgery to 30?Gy at margin in 5 fractions of 9 static fields with a minimultileaf collimator and intensity modulated radiotherapy. Results. At 10 months following treatment, digital subtraction angiography showed complete obliteration of the AVM. Conclusions. Large bilateral thalamic and basal ganglia AVMs can be successfully treated with complete obliteration by HFSRS with IMRT with relatively limited toxicity. Appropriate caution is recommended. PMID:24307961

Nanda, Ashish; Litofsky, N. Scott

2013-01-01

94

Dopamine transporter SPECT/CT and perfusion brain SPECT imaging in idiopathic basal ganglia calcinosis.  

PubMed

A case of idiopathic basal ganglia calcification in a 56-year-old woman with parkinsonism and cognitive impairment is described. The nigrostriatal dopaminergic pathway and regional cerebral blood flow were evaluated using dopamine transporter (DAT) brain single photon emission tomography combined with a low-dose x-ray computerized tomography transmission (hybrid SPECT/CT) and Tc-99m HMPAO brain perfusion SPECT study, respectively. DAT SPECT/CT imaging revealed a reduction in DAT binding in both striatum regions coinciding with bilateral calcifications in the basal ganglia. Brain perfusion scan showed hypoperfusion in basal ganglia regions, posterior parietal cortex bilaterally, left frontopolar and dorsolateral prefrontal cortex, and left temporal lobe. These findings correlated well with the clinical condition of the patient. Mineralization may play a critical role in the pathogenesis of neuronal degeneration. Cortical perfusion changes in patients may better explain the patient's altered cognitive and motor functions. PMID:19542944

Paschali, Anna; Lakiotis, Velissarios; Messinis, Lambros; Markaki, Elli; Constantoyannis, Constantine; Ellul, John; Vassilakos, Pavlos

2009-07-01

95

[A pathomechanism for the genesis of dystonia: striatal compartments and hypothesized model of basal ganglia circuits].  

PubMed

X-linked recessive dystonia-parkinsonism (XDP; DYT3; Lubag) is an adult-onset disorder that manifests severe and progressive dystonia with a high frequency of generalization. In search for the anatomical basis for dystonia, we performed postmortem analyses of the functional anatomy of the basal ganglia based on the striatal compartments (i.e., the striosomes and matrix compartment) in XDP. Our study showed that in the XDP neostriatum, the matrix compartment is relatively spared in a mosaic pattern, whereas the striosomes are severely depleted. In view of the three-pathway basal ganglia model, we postulate that the disproportionate involvement of neostriatal compartments and their efferent projections may underlie the manifestation of dystonia in patients with XDP. This study is the first to show specific basal ganglia pathology that could explain the genesis of dystonia in human heredodegenerative movement disorders, suggesting that dystonia may result from an imbalance in the activity between the striosomal and matrix pathways. PMID:17432234

Goto, Satoshi

2006-11-01

96

Phenotypic spectrum of probable and genetically-confirmed idiopathic basal ganglia calcification.  

PubMed

Idiopathic basal ganglia calcification is characterized by mineral deposits in the brain, an autosomal dominant pattern of inheritance in most cases and genetic heterogeneity. The first causal genes, SLC20A2 and PDGFRB, have recently been reported. Diagnosing idiopathic basal ganglia calcification necessitates the exclusion of other causes, including calcification related to normal ageing, for which no normative data exist. Our objectives were to diagnose accurately and then describe the clinical and radiological characteristics of idiopathic basal ganglia calcification. First, calcifications were evaluated using a visual rating scale on the computerized tomography scans of 600 consecutively hospitalized unselected controls. We determined an age-specific threshold in these control computerized tomography scans as the value of the 99th percentile of the total calcification score within three age categories: <40, 40-60, and >60 years. To study the phenotype of the disease, patients with basal ganglia calcification were recruited from several medical centres. Calcifications that rated below the age-specific threshold using the same scale were excluded, as were patients with differential diagnoses of idiopathic basal ganglia calcification, after an extensive aetiological assessment. Sanger sequencing of SLC20A2 and PDGFRB was performed. In total, 72 patients were diagnosed with idiopathic basal ganglia calcification, 25 of whom bore a mutation in either SLC20A2 (two families, four sporadic cases) or PDGFRB (one family, two sporadic cases). Five mutations were novel. Seventy-one per cent of the patients with idiopathic basal ganglia calcification were symptomatic (mean age of clinical onset: 39 ± 20 years; mean age at last evaluation: 55 ± 19 years). Among them, the most frequent signs were: cognitive impairment (58.8%), psychiatric symptoms (56.9%) and movement disorders (54.9%). Few clinical differences appeared between SLC20A2 and PDGFRB mutation carriers. Radiological analysis revealed that the total calcification scores correlated positively with age in controls and patients, but increased more rapidly with age in patients. The expected total calcification score was greater in SLC20A2 than PDGFRB mutation carriers, beyond the effect of the age alone. No patient with a PDGFRB mutation exhibited a cortical or a vermis calcification. The total calcification score was more severe in symptomatic versus asymptomatic individuals. We provide the first phenotypical description of a case series of patients with idiopathic basal ganglia calcification since the identification of the first causative genes. Clinical and radiological diversity is confirmed, whatever the genetic status. Quantification of calcification is correlated with the symptomatic status, but the location and the severity of the calcifications don't reflect the whole clinical diversity. Other biomarkers may be helpful in better predicting clinical expression. PMID:24065723

Nicolas, Gaël; Pottier, Cyril; Charbonnier, Camille; Guyant-Maréchal, Lucie; Le Ber, Isabelle; Pariente, Jérémie; Labauge, Pierre; Ayrignac, Xavier; Defebvre, Luc; Maltête, David; Martinaud, Olivier; Lefaucheur, Romain; Guillin, Olivier; Wallon, David; Chaumette, Boris; Rondepierre, Philippe; Derache, Nathalie; Fromager, Guillaume; Schaeffer, Stéphane; Krystkowiak, Pierre; Verny, Christophe; Jurici, Snejana; Sauvée, Mathilde; Vérin, Marc; Lebouvier, Thibaud; Rouaud, Olivier; Thauvin-Robinet, Christel; Rousseau, Stéphane; Rovelet-Lecrux, Anne; Frebourg, Thierry; Campion, Dominique; Hannequin, Didier

2013-11-01

97

[Prevalence and clinical significance of computerized tomography verified idiopathic calcinosis of the basal ganglia].  

PubMed

With increasing CT examinations of the cerebrum, the discovery of basal ganglia calcification becomes more frequent. In order to correlate these calcifications to the symptoms believed to be accompanied with Fahr's disease 2318 cranial CT scans were examined. There was an overall incidence of basal ganglia calcification of 12.5%. The most frequent location was the globus pallidus (96.4%). In the examined population there was no correlation found between the calcifications and symptoms having been described with striopallidentate calcifications. PMID:11253108

Gomille, T; Meyer, R A; Falkai, P; Gaebel, W; Königshausen, T; Christ, F

2001-02-01

98

Conditional Routing of Information to the Cortex: A Model of the Basal Ganglia's Role in Cognitive Coordination  

ERIC Educational Resources Information Center

The basal ganglia play a central role in cognition and are involved in such general functions as action selection and reinforcement learning. Here, we present a model exploring the hypothesis that the basal ganglia implement a conditional information-routing system. The system directs the transmission of cortical signals between pairs of regions…

Stocco, Andrea; Lebiere, Christian; Anderson, John R.

2010-01-01

99

The sensory guidance of movement: a comparison of the cerebellum and basal ganglia  

Microsoft Academic Search

We used positron emission tomography (PET) to compare the contribution of the cerebellum and basal ganglia to the sensory guidance of movement. In one condition the subjects used a computer mouse to draw a series of lines on a computer screen (DRAW). In the second condition the same lines were presented to the subjects, and they had to track the

J. Jueptner; M. Jueptner; I. H. Jenkins; D. J. Brooks; R. S. J. Frackowiak; R. E. Passingham

1996-01-01

100

Basal ganglia network by constrained spherical deconvolution: A possible cortico-pallidal pathway?  

PubMed

In the recent past, basal ganglia circuitry was simplified as represented by the direct and indirect pathways and by hyperdirect pathways. Based on data from animal studies, we hypothesized a fourth pathway, the cortico-pallidal, pathway, that complements the hyperdirect pathway to the subthalamus. Ten normal brains were analyzed by using the high angular resolution diffusion imaging-constrained spherical deconvolution (CSD)-based technique. The study was performed with a 3T magnetic resonance imaging (MRI) scanner (Achieva, Philips Healthcare, Best, Netherlands); by using a 32-channel SENSE head coil. We showed that CSD is a powerful technique that allows a fine evaluation of both the long and small tracts between cortex and basal ganglia, including direct, indirect, and hyperdirect pathways. In addition, a pathway directly connecting the cortex to the globus pallidus was seen. Our results confirm that the CSD tractography is a valuable technique allowing a reliable reconstruction of small- and long-fiber pathways in brain regions with multiple fiber orientations, such as basal ganglia. This could open a future scenario in which CSD could be used to focally target with deep brain stimulation (DBS) the small bundles within the basal ganglia loops. © 2014 International Parkinson and Movement Disorder Society. PMID:25156805

Milardi, Demetrio; Gaeta, Michele; Marino, Silvia; Arrigo, Alessandro; Vaccarino, Gianluigi; Mormina, Enricomaria; Rizzo, Giuseppina; Milazzo, Carmelo; Finocchio, Giovanni; Baglieri, Annalisa; Anastasi, Giuseppe; Quartarone, Angelo

2014-08-22

101

The Role of the Basal Ganglia in Implicit Contextual Learning: A Study of Parkinson's Disease  

ERIC Educational Resources Information Center

Implicit contextual learning refers to the ability to memorize contextual information from our environment. This contextual information can then be used to guide our attention to a specific location. Although the medial temporal lobe is important for this type of learning, the basal ganglia might also be involved considering its role in many…

van Asselen, Marieke; Almeida, Ines; Andre, Rui; Januario, Cristina; Goncalves, Antonio Freire; Castelo-Branco, Miguel

2009-01-01

102

The corticostriatal projection: from synaptic plasticity to dysfunctions of the basal ganglia  

Microsoft Academic Search

Corticostriatal transmission has an important function in the regulation of the neuronal activity of the basal ganglia. The firing activity of corticostriatal neurones excites striatal cells via the release of glutamate. Presynaptic receptors that are located on corticostriatal terminals and that regulate the release of glutamate in the striatum have been postulated for dopamine and glutamate. Activation of these receptors

Paolo Calabresi; Antonio Pisani; Nicola B. Mercuri; Giorgio Bernardi

1996-01-01

103

The clinical significance of bilateral basal ganglia calcification presenting with mania and delusions.  

PubMed

The authors present the case of a 37-year-old man who developed a psychotic manic episode and was found to have bilateral basal ganglia calcification (BGC). The authors present this case report along with a discussion of the literature on the neuropsychiatry of BGC. PMID:23487196

Johnson, Justin M; Legesse, Benalfew; Camprodon, Joan A; Murray, Evan; Price, Bruce H

2013-01-01

104

Differential contributions of basal ganglia and thalamus to song initiation, tempo, and structure.  

PubMed

Basal ganglia-thalamocortical circuits are multistage loops critical to motor behavior, but the contributions of individual components to overall circuit function remain unclear. We addressed these issues in a songbird basal ganglia-thalamocortical circuit (the anterior forebrain pathway, AFP) specialized for singing and critical for vocal plasticity. The major known afferent to the AFP is the premotor cortical nucleus, HVC. Surprisingly, previous studies found that lesions of HVC alter song but do not eliminate the ability of the AFP to drive song production. We therefore used this AFP-driven song to investigate the role of basal ganglia and thalamus in vocal structure, tempo, and initiation. We found that lesions of the striatopallidal component (Area X) slowed song and simplified its acoustic structure. Elimination of the thalamic component (DLM) further simplified the acoustic structure of song and regularized its rhythm but also dramatically reduced song production. The acoustic structure changes imply that sequential stages of the AFP each add complexity to song, but the effects of DLM lesions on song initiation suggest that thalamus is a locus of additional inputs important to initiation. Together, our results highlight the cumulative contribution of stages of a basal ganglia-thalamocortical circuit to motor output along with distinct involvement of thalamus in song initiation or "gating." PMID:24174647

Chen, J R; Stepanek, L; Doupe, A J

2014-01-01

105

Dissociation between medial temporal lobe and basal ganglia memory systems in schizophrenia  

E-print Network

-equivalent dose of antipsychotics. In conclusion, this is the first study to show that patients with schizophrenia. High-dose first generation antipsychotics may disrupt BG-dependent learning by blocking dopaminergic; Learning; Memory; Antipsychotics; Parkinsonism; Medial temporal lobe; Basal ganglia; Acquired equivalence 1

Gluck, Mark

106

Visuo-Motor and Cognitive Procedural Learning in Children with Basal Ganglia Pathology  

ERIC Educational Resources Information Center

We investigated procedural learning in 18 children with basal ganglia (BG) lesions or dysfunctions of various aetiologies, using a visuo-motor learning test, the Serial Reaction Time (SRT) task, and a cognitive learning test, the Probabilistic Classification Learning (PCL) task. We compared patients with early (less than 1 year old, n=9), later…

Mayor-Dubois, C.; Maeder, P.; Zesiger, P.; Roulet-Perez, E.

2010-01-01

107

Alterations in neuronal activity in basal ganglia-thalamocortical circuits in the parkinsonian state  

PubMed Central

In patients with Parkinson’s disease and in animal models of this disorder, neurons in the basal ganglia and related regions in thalamus and cortex show changes that can be recorded by using electrophysiologic single-cell recording techniques, including altered firing rates and patterns, pathologic oscillatory activity and increased inter-neuronal synchronization. In addition, changes in synaptic potentials or in the joint spiking activities of populations of neurons can be monitored as alterations in local field potentials (LFPs), electroencephalograms (EEGs) or electrocorticograms (ECoGs). Most of the mentioned electrophysiologic changes are probably related to the degeneration of diencephalic dopaminergic neurons, leading to dopamine loss in the striatum and other basal ganglia nuclei, although degeneration of non-dopaminergic cell groups may also have a role. The altered electrical activity of the basal ganglia and associated nuclei may contribute to some of the motor signs of the disease. We here review the current knowledge of the electrophysiologic changes at the single cell level, the level of local populations of neural elements, and the level of the entire basal ganglia-thalamocortical network in parkinsonism, and discuss the possible use of this information to optimize treatment approaches to Parkinson’s disease, such as deep brain stimulation (DBS) therapy.

Galvan, Adriana; Devergnas, Annaelle; Wichmann, Thomas

2015-01-01

108

The inhibitory microcircuit of the substantia nigra provides feedback gain control of the basal ganglia output  

PubMed Central

Dysfunction of the basal ganglia produces severe deficits in the timing, initiation, and vigor of movement. These diverse impairments suggest a control system gone awry. In engineered systems, feedback is critical for control. By contrast, models of the basal ganglia highlight feedforward circuitry and ignore intrinsic feedback circuits. In this study, we show that feedback via axon collaterals of substantia nigra projection neurons control the gain of the basal ganglia output. Through a combination of physiology, optogenetics, anatomy, and circuit mapping, we elaborate a general circuit mechanism for gain control in a microcircuit lacking interneurons. Our data suggest that diverse tonic firing rates, weak unitary connections and a spatially diffuse collateral circuit with distinct topography and kinetics from feedforward input is sufficient to implement divisive feedback inhibition. The importance of feedback for engineered systems implies that the intranigral microcircuit, despite its absence from canonical models, could be essential to basal ganglia function. DOI: http://dx.doi.org/10.7554/eLife.02397.001 PMID:24849626

Brown, Jennifer; Pan, Wei-Xing; Dudman, Joshua Tate

2014-01-01

109

Providing Explicit Information Disrupts Implicit Motor Learning after Basal Ganglia Stroke  

ERIC Educational Resources Information Center

Despite their purported neuroanatomic and functional isolation, empirical evidence suggests that sometimes conscious explicit processes can influence implicit motor skill learning. Our goal was to determine if the provision of explicit information affected implicit motor-sequence learning after damage to the basal ganglia. Individuals with stroke…

Boyd, Lara A.; Winstein, Carolee J.

2004-01-01

110

Basal ganglia and supplementary motor area subtend duration perception: an fMRI study  

Microsoft Academic Search

Brain imaging studies on duration perception usually report the activation of a network that includes the frontal and mesiofrontal cortex (supplementary motor area, SMA), parietal cortex, and subcortical areas (basal ganglia, thalamus, and cerebellum). To address the question of the specific involvement of these structures in temporal processing, we contrasted two visual discrimination tasks in which the relevant stimulus dimension

A. M. Ferrandez; L. Hugueville; S. Lehericy; J. B. Poline; C. Marsault; V. Pouthasa

2003-01-01

111

Effects of Focal Basal Ganglia Lesions on Timing and Force Control  

ERIC Educational Resources Information Center

Studies of basal ganglia dysfunction in humans have generally involved patients with degenerative disorders, notably Parkinson's disease. In many instances, the performance of these patients is compared to that of patients with focal lesions of other brain structures such as the cerebellum. In the present report, we studied the performance of…

Aparicio, P.; Diedrichsen, J.; Ivry, R.B.

2005-01-01

112

Differential contributions of basal ganglia and thalamus to song initiation, tempo, and structure  

PubMed Central

Basal ganglia-thalamocortical circuits are multistage loops critical to motor behavior, but the contributions of individual components to overall circuit function remain unclear. We addressed these issues in a songbird basal ganglia-thalamocortical circuit (the anterior forebrain pathway, AFP) specialized for singing and critical for vocal plasticity. The major known afferent to the AFP is the premotor cortical nucleus, HVC. Surprisingly, previous studies found that lesions of HVC alter song but do not eliminate the ability of the AFP to drive song production. We therefore used this AFP-driven song to investigate the role of basal ganglia and thalamus in vocal structure, tempo, and initiation. We found that lesions of the striatopallidal component (Area X) slowed song and simplified its acoustic structure. Elimination of the thalamic component (DLM) further simplified the acoustic structure of song and regularized its rhythm but also dramatically reduced song production. The acoustic structure changes imply that sequential stages of the AFP each add complexity to song, but the effects of DLM lesions on song initiation suggest that thalamus is a locus of additional inputs important to initiation. Together, our results highlight the cumulative contribution of stages of a basal ganglia-thalamocortical circuit to motor output along with distinct involvement of thalamus in song initiation or “gating.” PMID:24174647

Chen, J. R.; Doupe, A. J.

2013-01-01

113

How may the basal ganglia contribute to auditory categorization and speech perception?  

PubMed Central

Listeners must accomplish two complementary perceptual feats in extracting a message from speech. They must discriminate linguistically-relevant acoustic variability and generalize across irrelevant variability. Said another way, they must categorize speech. Since the mapping of acoustic variability is language-specific, these categories must be learned from experience. Thus, understanding how, in general, the auditory system acquires and represents categories can inform us about the toolbox of mechanisms available to speech perception. This perspective invites consideration of findings from cognitive neuroscience literatures outside of the speech domain as a means of constraining models of speech perception. Although neurobiological models of speech perception have mainly focused on cerebral cortex, research outside the speech domain is consistent with the possibility of significant subcortical contributions in category learning. Here, we review the functional role of one such structure, the basal ganglia. We examine research from animal electrophysiology, human neuroimaging, and behavior to consider characteristics of basal ganglia processing that may be advantageous for speech category learning. We also present emerging evidence for a direct role for basal ganglia in learning auditory categories in a complex, naturalistic task intended to model the incidental manner in which speech categories are acquired. To conclude, we highlight new research questions that arise in incorporating the broader neuroscience research literature in modeling speech perception, and suggest how understanding contributions of the basal ganglia can inform attempts to optimize training protocols for learning non-native speech categories in adulthood. PMID:25136291

Lim, Sung-Joo; Fiez, Julie A.; Holt, Lori L.

2014-01-01

114

Subclinical Visuospatial Impairment in Parkinson’s Disease: The Role of Basal Ganglia and Limbic System  

PubMed Central

Background: Visual perception deficits are a recurrent manifestation in Parkinson’s disease (PD). Recently, structural abnormalities of fronto-parietal areas and subcortical regions, implicated in visual stimuli analysis, have been observed in PD patients with cognitive decline and visual hallucinations. The aim of the present study was to investigate the salient aspects of visual perception in cognitively unimpaired PD patients. Methods: Eleven right-handed non-demented right-sided onset PD patients without visuospatial impairment or hallucinations and 11 healthy controls were studied with functional magnetic resonance imaging while performing a specific visuoperceptual/visuospatial paradigm that allowed to highlight the specific process underlying visuospatial judgment. Results: Significant changes in both cortical areas and subcortical regions involved in visual stimuli processing were observed. In particular, PD patients showed a reduced activation for the right insula, left putamen, bilateral caudate, and right hippocampus, as well as an over-activation of the right dorso-lateral prefrontal and of the posterior parietal cortices, particularly in the right hemisphere. Conclusions: We found that both loss of efficiency and compensatory mechanisms occur in PD patients, providing further insight into the pathophysiological role of the functional alterations of basal ganglia and limbic structures in the impairment of visuoperceptual and visuospatial functions observed in PD. PMID:25157239

Caproni, Stefano; Muti, Marco; Di Renzo, Antonio; Principi, Massimo; Caputo, Nevia; Calabresi, Paolo; Tambasco, Nicola

2014-01-01

115

Mineral composition of and the relationships between them of human basal ganglia in very old age.  

PubMed

Trace elements and the relationships among them were investigated by direct chemical analysis in three basal ganglia regions in very old age individuals and age- and gender-related differences were assessed. After ordinary dissections at Nara Medical University were finished, the caudate nucleus, putamen, and globus pallidus belonging to the basal ganglia were removed from the identical cerebra of the subjects who consisted of 22 men and 23 women, ranging in age from 70 to 101 years (average age?=?83.3?±?7.5 years). After incineration with nitric acid and perchloric acid, the element contents were determined by inductively coupled plasma-atomic emission spectrometry. It was found that the Ca, P, and Mg contents increased significantly in the putamen with aging and the Mg content increased significantly in the globus pallidus with aging, but no elements increased significantly in the caudate nucleus with aging. Regarding the relationships among elements in the basal ganglia, extremely significant direct correlations were found among the Ca, P, and Mg contents in the putamen. These results suggested that slight calcification occurred in the putamen in very old age. With regard to seven elements of Ca, P, S, Mg, Zn, Fe, and Na, it was examined whether there were significant correlations among the caudate nucleus, putamen, and globus pallidus. It was found that there were extremely significant direct correlations among all of the three basal ganglia in the P content. Likewise, with regard to the Fe content, there were extremely or very significant direct correlations among all of the three basal ganglia. Regarding the gender difference in elements, it was found that the Ca content of the caudate nucleus was significantly higher in women than in men. PMID:23111949

Tohno, Yoshiyuki; Tohno, Setsuko; Azuma, Cho; Minami, Takeshi; Ke, Lining; Ongkana, Nutcharin; Sinthubua, Apichat; Mahakkanukrauh, Pasuk

2013-01-01

116

Decreased basal ganglia activation in subjects with chronic fatigue syndrome: association with symptoms of fatigue.  

PubMed

Reduced basal ganglia function has been associated with fatigue in neurologic disorders, as well as in patients exposed to chronic immune stimulation. Patients with chronic fatigue syndrome (CFS) have been shown to exhibit symptoms suggestive of decreased basal ganglia function including psychomotor slowing, which in turn was correlated with fatigue. In addition, CFS patients have been found to exhibit increased markers of immune activation. In order to directly test the hypothesis of decreased basal ganglia function in CFS, we used functional magnetic resonance imaging to examine neural activation in the basal ganglia to a reward-processing (monetary gambling) task in a community sample of 59 male and female subjects, including 18 patients diagnosed with CFS according to 1994 CDC criteria and 41 non-fatigued healthy controls. For each subject, the average effect of winning vs. losing during the gambling task in regions of interest (ROI) corresponding to the caudate nucleus, putamen, and globus pallidus was extracted for group comparisons and correlational analyses. Compared to non-fatigued controls, patients with CFS exhibited significantly decreased activation in the right caudate (p?=?0.01) and right globus pallidus (p?=?0.02). Decreased activation in the right globus pallidus was significantly correlated with increased mental fatigue (r2?=?0.49, p?=?0.001), general fatigue (r2?=?0.34, p?=?0.01) and reduced activity (r2?=?0.29, p?=?0.02) as measured by the Multidimensional Fatigue Inventory. No such relationships were found in control subjects. These data suggest that symptoms of fatigue in CFS subjects were associated with reduced responsivity of the basal ganglia, possibly involving the disruption of projections from the globus pallidus to thalamic and cortical networks. PMID:24858857

Miller, Andrew H; Jones, James F; Drake, Daniel F; Tian, Hao; Unger, Elizabeth R; Pagnoni, Giuseppe

2014-01-01

117

Decreased Basal Ganglia Activation in Subjects with Chronic Fatigue Syndrome: Association with Symptoms of Fatigue  

PubMed Central

Reduced basal ganglia function has been associated with fatigue in neurologic disorders, as well as in patients exposed to chronic immune stimulation. Patients with chronic fatigue syndrome (CFS) have been shown to exhibit symptoms suggestive of decreased basal ganglia function including psychomotor slowing, which in turn was correlated with fatigue. In addition, CFS patients have been found to exhibit increased markers of immune activation. In order to directly test the hypothesis of decreased basal ganglia function in CFS, we used functional magnetic resonance imaging to examine neural activation in the basal ganglia to a reward-processing (monetary gambling) task in a community sample of 59 male and female subjects, including 18 patients diagnosed with CFS according to 1994 CDC criteria and 41 non-fatigued healthy controls. For each subject, the average effect of winning vs. losing during the gambling task in regions of interest (ROI) corresponding to the caudate nucleus, putamen, and globus pallidus was extracted for group comparisons and correlational analyses. Compared to non-fatigued controls, patients with CFS exhibited significantly decreased activation in the right caudate (p?=?0.01) and right globus pallidus (p?=?0.02). Decreased activation in the right globus pallidus was significantly correlated with increased mental fatigue (r2?=?0.49, p?=?0.001), general fatigue (r2?=?0.34, p?=?0.01) and reduced activity (r2?=?0.29, p?=?0.02) as measured by the Multidimensional Fatigue Inventory. No such relationships were found in control subjects. These data suggest that symptoms of fatigue in CFS subjects were associated with reduced responsivity of the basal ganglia, possibly involving the disruption of projections from the globus pallidus to thalamic and cortical networks. PMID:24858857

Miller, Andrew H.; Jones, James F.; Drake, Daniel F.; Tian, Hao; Unger, Elizabeth R.; Pagnoni, Giuseppe

2014-01-01

118

Extrapyramidal symptoms and advanced calcification of the basal ganglia in a patient with autosomal dominant hypocalcemia.  

PubMed

Most cases of hypoparathyroidism with decreased parathyroid hormone (PTH) secretion, excluding secondary hypoparathyroidism, are considered to be idiopathic. We herein report a relatively rare case of hypoparathyroidism with extrapyramidal symptoms, including brachybasia and a frozen gait, caused by advanced basal ganglia calcification in a 64-year-old man with hypoparathyroidism. A DNA (deoxyribonucleic acid) analysis of blood samples obtained from the patient and his eldest daughter revealed autosomal dominant hypocalcemia (ADH) with mutations in the calcium-sensing receptor (CaSR) gene. In cases of chronic hypoparathyroidism, calcification of the basal ganglia is observed if the patient is not treated for a long period. However, extrapyramidal symptoms as a complication of hypoparathyroidism are relatively rare. PMID:24042516

Kurozumi, Akira; Okada, Yosuke; Arao, Tadashi; Endou, Itsuro; Matsumoto, Toshio; Tanaka, Yoshiya

2013-01-01

119

Balanced activity in basal ganglia projection pathways is critical for contraversive movements  

PubMed Central

The basal ganglia, and the striatum in particular, have been implicated in the generation of contraversive movements. The striatum projects to downstream basal ganglia nuclei through two main circuits, originating in striatonigral and striatopallidal neurons, and different models postulate that the two pathways can work in opposition or synergistically. Here we show striatonigral and striatopallidal neurons are concurrently active during spontaneous contraversive movements. Furthermore, we show that unilateral optogenetic inhibition of either or both projection pathways disrupts contraversive movements. Consistently, simultaneous activation of both neuron types produces contraversive movements. Still, we also show that imbalanced activity between the pathways can result in opposing movements being driven by each projection pathway. These data show that balanced activity in both striatal projection pathways is critical for the generation of contraversive movements and highlights that imbalanced activity between the two projection pathways can result in opposing motor output. PMID:25002180

Tecuapetla, Fatuel; Matias, Sara; Dugue, Guillaume P.; Mainen, Zachary F.; Costa, Rui M.

2014-01-01

120

Evidence for a causal inverse model in an avian cortico-basal ganglia circuit  

PubMed Central

Learning by imitation is fundamental to both communication and social behavior and requires the conversion of complex, nonlinear sensory codes for perception into similarly complex motor codes for generating action. To understand the neural substrates underlying this conversion, we study sensorimotor transformations in songbird cortical output neurons of a basal-ganglia pathway involved in song learning. Despite the complexity of sensory and motor codes, we find a simple, temporally specific, causal correspondence between them. Sensory neural responses to song playback mirror motor-related activity recorded during singing, with a temporal offset of roughly 40 ms, in agreement with short feedback loop delays estimated using electrical and auditory stimulation. Such matching of mirroring offsets and loop delays is consistent with a recent Hebbian theory of motor learning and suggests that cortico-basal ganglia pathways could support motor control via causal inverse models that can invert the rich correspondence between motor exploration and sensory feedback. PMID:24711417

Giret, Nicolas; Kornfeld, Joergen; Ganguli, Surya; Hahnloser, Richard H. R.

2014-01-01

121

Crossed cerebellar and uncrossed basal ganglia and thalamic diaschisis in Alzheimer's disease  

SciTech Connect

We detected crossed cerebellar as well as uncrossed basal ganglia and thalamic diaschisis in Alzheimer's disease by positron emission tomography (PET) using /sup 18/F-fluorodeoxyglucose. We studied a series of 26 consecutive, clinically diagnosed Alzheimer cases, including 6 proven by later autopsy, and compared them with 9 age-matched controls. We calculated asymmetry indices (AIs) of cerebral metabolic rate for matched left-right regions of interest (ROIs) and determined the extent of diaschisis by correlative analyses. For the Alzheimer group, we found cerebellar AIs correlated negatively, and thalamic AIs positively, with those of the cerebral hemisphere and frontal, temporal, parietal, and angular cortices, while basal ganglia AIs correlated positively with frontal cortical AIs. The only significant correlation of AIs for normal subjects was between the thalamus and cerebral hemisphere. These data indicate that PET is a sensitive technique for detecting diaschisis.

Akiyama, H.; Harrop, R.; McGeer, P.L.; Peppard, R.; McGeer, E.G.

1989-04-01

122

Does it talk the talk? On the role of basal ganglia in emotive speech processing.  

PubMed

Ackermann et al.'s phylogenetic account of speech argues that the basal ganglia imbue speech with emotive content. However, a body of work on auditory/emotive processing is inconsistent with attributing this function exclusively to these structures. The account further overlooks the possibility that the emotion-integration function may be at least in part mediated by the cortico-ponto-cerebellar system. PMID:25514946

Hasson, Uri; Llano, Daniel A; Miceli, Gabriele; Dick, Anthony Steven

2014-12-01

123

Case Study: Acute Basal Ganglia Enlargement and Obsessive-Compulsive Symptoms in an Adolescent Boy  

Microsoft Academic Search

Pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAs) may arise when antibodies directed against invading bacteria cross-react with basal ganglia structures, resulting in exacerbations of obsessive-compulsive disorder (OCD) or tic disorders. This is a report of severe worsening of obsessive-compulsive symptoms In an adolescent boy following infection with group A ?-hemolytic streptococci for whom serial magnetic resonance imaging scans

JAY N. GIEDD; JUDITH L. RAPOPORT; HENRIETTA L. LEONARD; DANIEL RICHTER; SUSAN E. SWEDO

1996-01-01

124

A role of the basal ganglia and midbrain nuclei for initiation of motor sequences  

Microsoft Academic Search

The mesial premotor cortex is crucial for planning sequential procedures and movement initiation. With event-related (ER) functional magnetic resonance imaging (fMRI) it has been possible to separate mesial premotor activation before, during, and after self-initiated movements and, thereby, to distinguish advance planning from execution. The mesial premotor cortex is part of distributed cortico-basal ganglia-thalamo-cortical networks but, to date, the subcortical

H. Boecker; J. Jankowski; P. Ditter; L. Scheef

2008-01-01

125

Hypomyelination with atrophy of the basal ganglia and cerebellum: further delineation of the phenotype and genotype-phenotype correlation.  

PubMed

Hypomyelination with atrophy of the basal ganglia and cerebellum is a rare leukoencephalopathy that was identified using magnetic resonance imaging in 2002. In 2013, whole exome sequencing of 11 patients with the disease revealed that they all had the same de novo mutation in TUBB4A, which encodes tubulin ?-4A. We investigated the mutation spectrum in a cohort of 42 patients and the relationship between genotype and phenotype. Patients were selected on the basis of clinical and magnetic resonance imaging abnormalities that are indicative of hypomyelination with atrophy of the basal ganglia and cerebellum. Genetic testing and a clinical inventory were performed, and sequential magnetic resonance images were evaluated using a standard protocol. The heterozygous TUBB4A mutation observed in the first 11 patients was the most common (25 patients). Additionally, 13 other heterozygous mutations were identified, located in different structural domains of tubulin ?-4A. We confirmed that the mutations were de novo in all but three patients. In two of these three cases we lacked parental DNA and in one the mutation was also found in the mother, most likely due to mosaicism. Patients showed a phenotypic continuum ranging from neonatal to childhood disease onset, normal to delayed early development and slow to more rapid neurological deterioration. Neurological symptomatology consisted of extrapyramidal movement abnormalities, spasticity, ataxia, cognitive deficit and sometimes epilepsy. Three patients died and the oldest living patient was 29 years of age. The patients' magnetic resonance images showed an absent or disappearing putamen, variable cerebellar atrophy and highly variable cerebral atrophy. Apart from hypomyelination, myelin loss was evident in several cases. Three severely affected patients had similar, somewhat atypical magnetic resonance image abnormalities. The study results were strongly suggestive of a genotype-phenotype correlation. The 25 patients with the common c.745G>A mutation generally had a less rapidly progressive disease course than the 17 cases with other TUBB4A mutations. Overall, this work demonstrates that the distinctive magnetic resonance imaging pattern for hypomyelination with atrophy of the basal ganglia and cerebellum defines a homogeneous clinical phenotype of variable severity. Patients almost invariably have prominent extrapyramidal movement abnormalities, which are rarely seen in patients with hypomyelination of different origin. A dominant TUBB4A mutation is also associated with dystonia type 4, in which magnetic resonance images of the brain seem normal. It is highly likely that there is a disease continuum associated with TUBB4A mutations, of which hypomyelination with atrophy of the basal ganglia and cerebellum and dystonia type 4 are the extremes. This would indicate that extrapyramidal movement abnormalities constitute the core feature of the disease spectrum related to dominant TUBB4A mutations and that all other features are variable. PMID:24785942

Hamilton, Eline M; Polder, Emiel; Vanderver, Adeline; Naidu, Sakkubai; Schiffmann, Raphael; Fisher, Kate; Raguž, Ana Boban; Blumkin, Luba; van Berkel, Carola G M; Waisfisz, Quinten; Simons, Cas; Taft, Ryan J; Abbink, Truus E M; Wolf, Nicole I; van der Knaap, Marjo S

2014-07-01

126

Interruption of a basal ganglia-forebrain circuit prevents plasticity of learned vocalizations  

NASA Astrophysics Data System (ADS)

Birdsong, like speech, is a learned vocal behaviour that relies greatly on hearing; in both songbirds and humans the removal of auditory feedback by deafening leads to a gradual deterioration of adult vocal production. Here we investigate the neural mechanisms that contribute to the processing of auditory feedback during the maintenance of song in adult zebra finches. We show that the deleterious effects on song production that normally follow deafening can be prevented by a second insult to the nervous system-the lesion of a basal ganglia-forebrain circuit. The results suggest that the removal of auditory feedback leads to the generation of an instructive signal that actively drives non-adaptive changes in song; they also suggest that this instructive signal is generated within (or conveyed through) the basal ganglia-forebrain pathway. Our findings provide evidence that cortical-basal ganglia circuits may participate in the evaluation of sensory feedback during calibration of motor performance, and demonstrate that damage to such circuits can have little effect on previously learned behaviour while conspicuously disrupting the capacity to adaptively modify that behaviour.

Brainard, Michael S.; Doupe, Allison J.

2000-04-01

127

Brain tissue properties differentiate between motor and limbic basal ganglia circuits  

PubMed Central

Despite advances in understanding basic organizational principles of the human basal ganglia, accurate in vivo assessment of their anatomical properties is essential to improve early diagnosis in disorders with corticosubcortical pathology and optimize target planning in deep brain stimulation. Main goal of this study was the detailed topological characterization of limbic, associative, and motor subdivisions of the subthalamic nucleus (STN) in relation to corresponding corticosubcortical circuits. To this aim, we used magnetic resonance imaging and investigated independently anatomical connectivity via white matter tracts next to brain tissue properties. On the basis of probabilistic diffusion tractography we identified STN subregions with predominantly motor, associative, and limbic connectivity. We then computed for each of the nonoverlapping STN subregions the covariance between local brain tissue properties and the rest of the brain using high-resolution maps of magnetization transfer (MT) saturation and longitudinal (R1) and transverse relaxation rate (R2*). The demonstrated spatial distribution pattern of covariance between brain tissue properties linked to myelin (R1 and MT) and iron (R2*) content clearly segregates between motor and limbic basal ganglia circuits. We interpret the demonstrated covariance pattern as evidence for shared tissue properties within a functional circuit, which is closely linked to its function. Our findings open new possibilities for investigation of changes in the established covariance pattern aiming at accurate diagnosis of basal ganglia disorders and prediction of treatment outcome. PMID:24777915

Accolla, Ettore A; Dukart, Juergen; Helms, Gunther; Weiskopf, Nikolaus; Kherif, Ferath; Lutti, Antoine; Chowdhury, Rumana; Hetzer, Stefan; Haynes, John-Dylan; Kühn, Andrea A; Draganski, Bogdan

2014-01-01

128

Brain tissue properties differentiate between motor and limbic basal ganglia circuits.  

PubMed

Despite advances in understanding basic organizational principles of the human basal ganglia, accurate in vivo assessment of their anatomical properties is essential to improve early diagnosis in disorders with corticosubcortical pathology and optimize target planning in deep brain stimulation. Main goal of this study was the detailed topological characterization of limbic, associative, and motor subdivisions of the subthalamic nucleus (STN) in relation to corresponding corticosubcortical circuits. To this aim, we used magnetic resonance imaging and investigated independently anatomical connectivity via white matter tracts next to brain tissue properties. On the basis of probabilistic diffusion tractography we identified STN subregions with predominantly motor, associative, and limbic connectivity. We then computed for each of the nonoverlapping STN subregions the covariance between local brain tissue properties and the rest of the brain using high-resolution maps of magnetization transfer (MT) saturation and longitudinal (R1) and transverse relaxation rate (R2*). The demonstrated spatial distribution pattern of covariance between brain tissue properties linked to myelin (R1 and MT) and iron (R2*) content clearly segregates between motor and limbic basal ganglia circuits. We interpret the demonstrated covariance pattern as evidence for shared tissue properties within a functional circuit, which is closely linked to its function. Our findings open new possibilities for investigation of changes in the established covariance pattern aiming at accurate diagnosis of basal ganglia disorders and prediction of treatment outcome. PMID:24777915

Accolla, Ettore A; Dukart, Juergen; Helms, Gunther; Weiskopf, Nikolaus; Kherif, Ferath; Lutti, Antoine; Chowdhury, Rumana; Hetzer, Stefan; Haynes, John-Dylan; Kühn, Andrea A; Draganski, Bogdan

2014-10-01

129

Independent circuits in the basal ganglia for the evaluation and selection of actions.  

PubMed

The basal ganglia are critical for selecting actions and evaluating their outcome. Although the circuitry for selection is well understood, how these nuclei evaluate the outcome of actions is unknown. Here, we show in lamprey that a separate evaluation circuit, which regulates the habenula-projecting globus pallidus (GPh) neurons, exists within the basal ganglia. The GPh neurons are glutamatergic and can drive the activity of the lateral habenula, which, in turn, provides an indirect inhibitory influence on midbrain dopamine neurons. We show that GPh neurons receive inhibitory input from the striosomal compartment of the striatum. The striosomal input can reduce the excitatory drive to the lateral habenula and, consequently, decrease the inhibition onto the dopaminergic system. Dopaminergic neurons, in turn, provide feedback that inhibits the GPh. In addition, GPh neurons receive direct projections from the pallium (cortex in mammals), which can increase the GPh activity to drive the lateral habenula to increase the inhibition of the neuromodulatory systems. This circuitry, thus, differs markedly from the "direct" and "indirect" pathways that regulate the pallidal (e.g., globus pallidus) output nuclei involved in the control of motion. Our results show that a distinct reward-evaluation circuit exists within the basal ganglia, in parallel to the direct and indirect pathways, which select actions. Our results suggest that these circuits are part of the fundamental blueprint that all vertebrates use to select actions and evaluate their outcome. PMID:24003130

Stephenson-Jones, Marcus; Kardamakis, Andreas A; Robertson, Brita; Grillner, Sten

2013-09-17

130

The role of the basal ganglia in learning and memory: Insight from Parkinson's disease  

PubMed Central

It has long been known that memory is not a single process. Rather, there are different kinds of memory that are supported by distinct neural systems. This idea stemmed from early findings of dissociable patterns of memory impairments in patients with selective damage to different brain regions. These studies highlighted the role of the basal ganglia in non-declarative memory, such as procedural or habit learning, contrasting it with the known role of the medial temporal lobes in declarative memory. In recent years, major advances across multiple areas of neuroscience have revealed an important role for the basal ganglia in motivation and decision making. These findings have led to new discoveries about the role of the basal ganglia in learning and highlighted the essential role of dopamine in specific forms of learning. Here we review these recent advances with an emphasis on novel discoveries from studies of learning in patients with Parkinson's disease. We discuss how these findings promote the development of current theories away from accounts that emphasize the verbalizability of the contents of memory and towards a focus on the specific computations carried out by distinct brain regions. Finally, we discuss new challenges that arise in the face of accumulating evidence for dynamic and interconnected memory systems that jointly contribute to learning. PMID:21945835

2013-01-01

131

The pallial basal ganglia pathway modulates the behaviorally driven gene expression of the motor pathway  

PubMed Central

The discrete neural network for songbird vocal communication provides an effective system to study neural mechanisms of learned motor behaviors in vertebrates. This system consists of two pathways – a vocal motor pathway used to produce learned vocalizations and a vocal pallial basal ganglia loop used to learn and modify the vocalizations. However, it is not clear how the loop exerts control over the motor pathway. To study the mechanism, we used expression of the neural activity-induced gene ZENK (or egr-1), which shows singing-regulated expression in a social context-dependent manner: high levels in both pathways when singing undirected and low levels in the lateral part of the loop and in the robust nucleus of the arcopallium (RA) of the motor pathway when singing directed to another animal. Here, we show that there are two parallel interactive parts within the pallial basal ganglia loop, lateral and medial, which modulate singing-driven ZENK expression of the motor pathway nuclei RA and HVC, respectively. Within the loop, the striatal and pallial nuclei appear to have opposing roles; the striatal vocal nucleus lateral AreaX is required for high ZENK expression in its downstream nuclei, particularly during undirected singing, while the pallial vocal lateral magnocellular nucleus of the anterior nidopallium is required for lower expression, particularly during directed singing. These results suggest a dynamic molecular interaction between the basal ganglia pathway and the motor pathway during production of a learned motor behavior. PMID:17419760

Kubikova, Lubica; Turner, Elena A.; Jarvis, Erich D.

2008-01-01

132

Independent circuits in the basal ganglia for the evaluation and selection of actions  

PubMed Central

The basal ganglia are critical for selecting actions and evaluating their outcome. Although the circuitry for selection is well understood, how these nuclei evaluate the outcome of actions is unknown. Here, we show in lamprey that a separate evaluation circuit, which regulates the habenula-projecting globus pallidus (GPh) neurons, exists within the basal ganglia. The GPh neurons are glutamatergic and can drive the activity of the lateral habenula, which, in turn, provides an indirect inhibitory influence on midbrain dopamine neurons. We show that GPh neurons receive inhibitory input from the striosomal compartment of the striatum. The striosomal input can reduce the excitatory drive to the lateral habenula and, consequently, decrease the inhibition onto the dopaminergic system. Dopaminergic neurons, in turn, provide feedback that inhibits the GPh. In addition, GPh neurons receive direct projections from the pallium (cortex in mammals), which can increase the GPh activity to drive the lateral habenula to increase the inhibition of the neuromodulatory systems. This circuitry, thus, differs markedly from the “direct” and “indirect” pathways that regulate the pallidal (e.g., globus pallidus) output nuclei involved in the control of motion. Our results show that a distinct reward–evaluation circuit exists within the basal ganglia, in parallel to the direct and indirect pathways, which select actions. Our results suggest that these circuits are part of the fundamental blueprint that all vertebrates use to select actions and evaluate their outcome. PMID:24003130

Stephenson-Jones, Marcus; Kardamakis, Andreas A.; Robertson, Brita; Grillner, Sten

2013-01-01

133

Using point process models to determine the impact of visual cues on basal ganglia activity and behavior of Parkinson's patients  

E-print Network

Deep brain stimulation is an effective therapy for Parkinson's disease (PD) that has enabled microelectrode recordings from single-unit cells in the sub-thalamic nucleus (STN) of the basal ganglia. This rare data is important ...

Brown, Emery N.

134

Connections of the basal ganglia with the limbic system: implications for neuromodulation therapies of anxiety and affective disorders  

Microsoft Academic Search

The basal ganglia are best known for their role in motor planning and execution. However, it is currently widely accepted\\u000a that they are also involved in cognitive and emotional behaviors. Parts of the basal ganglia play a key role in reward and\\u000a reinforcement, addictive behaviors and habit formation. Pathophysiological processes underlying psychiatric disorders such\\u000a as depression, obsessive compulsive disorder and

P. Stathis; I. G. Panourias; M. S. Themistocleous; Damianos E. Sakas

135

Why we can talk, debate, and change our minds: Neural circuits, basal ganglia operations, and transcriptional factors.  

PubMed

Ackermann et al. disregard attested knowledge concerning aphasia, Parkinson disease, cortical-to-striatal circuits, basal ganglia, laryngeal phonation, and other matters. Their dual-pathway model cannot account for "what is special about the human brain." Their human cortical-to-laryngeal neural circuit does not exist. Basal ganglia operations, enhanced by mutations on FOXP2, confer human motor-control, linguistic, and cognitive capabilities. PMID:25514951

Lieberman, Philip

2014-12-01

136

Computational modeling of stuttering caused by impairments in a basal ganglia thalamo-cortical circuit involved in syllable selection and initiation  

PubMed Central

A typical white-matter integrity and elevated dopamine levels have been reported for individuals who stutter. We investigated how such abnormalities may lead to speech dysfluencies due to their effects on a syllable-sequencing circuit that consists of basal ganglia (BG), thalamus, and left ventral premotor cortex (vPMC). “Neurally impaired” versions of the neurocomputational speech production model GODIVA were utilized to test two hypotheses: (1) that white-matter abnormalities disturb the circuit via corticostriatal projections carrying copies of executed motor commands, and (2) that dopaminergic abnormalities disturb the circuit via the striatum. Simulation results support both hypotheses: in both scenarios, the neural abnormalities delay readout of the next syllable’s motor program, leading to dysfluency. The results also account for brain imaging findings during dysfluent speech. It is concluded that each of the two abnormality types can cause stuttering moments, probably by affecting the same BG-thalamus-vPMC circuit. PMID:23872286

Civier, Oren; Bullock, Daniel; Max, Ludo; Guenther, Frank H.

2013-01-01

137

The basal ganglia in perceptual timing: Timing performance in Multiple System Atrophy and Huntington's disease?  

PubMed Central

The timing of perceptual events depends on an anatomically and functionally connected network comprising basal ganglia, cerebellum, pre-frontal cortex and supplementary motor area. Recent studies demonstrate the cerebellum to be involved in absolute, duration-based timing, but not in relative timing based on a regular beat. Conversely, functional involvement of the striatum is observed in relative timing, but its role in absolute timing is unclear. This work tests the specific role of the basal ganglia in the perceptual timing of auditory events. It aims to distinguish the hypothesised unified model of time perception (Teki, Grube, & Griffiths, 2012), in which the striatum is a mandatory component for all timing tasks, from a modular system in which they subserve relative timing, with absolute timing processed by the cerebellum. Test groups comprised individuals with Multiple System Atrophy, a disorder in which similar pathology can produce clinical deficits associated with dysfunction of the cerebellum (MSA-C, n=8) or striatum (MSA-P, n=10), and early symptomatic Huntington's disease (HD, n=14). Individuals with chronic autoimmune peripheral neuropathy (n=11) acted as controls. Six adaptive tasks were carried out to assess perceptual thresholds for absolute timing through duration discrimination for sub- and supra-second time intervals, and relative timing through the detection of beat-based regularity and irregularity, detection of a delay within an isochronous sequence, and the discrimination of sequences with metrical structure. All three patient groups exhibited impairments in performance in comparison with the control group for all tasks, and severity of impairment was significantly correlated with disease progression. No differences were demonstrated between MSA-C and MSA-P, and the most severe impairments were observed in those with HD. The data support an obligatory role for the basal ganglia in all tested timing tasks, both absolute and relative, as predicted by the unified model. The results are not compatible with models of a brain timing network based upon independent modules. PMID:24135486

Cope, Thomas E.; Grube, Manon; Singh, Baldev; Burn, David J.; Griffiths, Timothy D.

2014-01-01

138

Association between a novel mutation in SLC20A2 and familial idiopathic basal ganglia calcification.  

PubMed

Familial idiopathic basal ganglia calcification (FIBGC) is a rare, autosomal dominant disorder involving bilateral calcification of the basal ganglia. To identify gene mutations related to a Chinese FIBGC lineage, we evaluated available individuals in the family using CT scans. DNA was extracted from the peripheral blood of available family members, and both exonic and flanking intronic sequences of the SLC20A2 gene were amplified by PCR and then sequenced. Non-denaturing polyacrylamide gel electrophoresis (PAGE) was used to confirm the presence of mutations. Allele imbalances of the SLC20A2 gene or relative quantity of SLC20A2 transcripts were evaluated using qRT-PCR. A novel heterozygous single base-pair deletion (c.510delA) within the SLC20A2 gene was identified. This deletion mutation was found to co-segregate with basal ganglia calcification in all of the affected family members but was not detected in unaffected individuals or in 167 unrelated Han Chinese controls. The mutation will cause a frameshift, producing a truncated SLC20A2 protein with a premature termination codon, most likely leading to the complete loss of function of the SLC20A2 protein. This mutation may also lead to a reduction in SLC20A2 mRNA expression by approximately 30% in cells from affected individuals. In conclusion, we identified a novel mutation in SLC20A2 that is linked to FIBGC. In addition to the loss of function at the protein level, decreasing the expression of SLC20A2 mRNA may be another mechanism that can regulate SLC20A2 function in IBGC individuals. We propose that the regional expression pattern of SLC20A1 and SLC20A2 might explain the unique calcification pattern observed in FIBGC patients. PMID:23437308

Zhang, Yang; Guo, Xianan; Wu, Anhua

2013-01-01

139

Rhythmic cortical neurons increase their oscillations and sculpt basal ganglia signaling during motor learning.  

PubMed

The function and modulation of neural circuits underlying motor skill may involve rhythmic oscillations (Feller, 1999; Marder and Goaillard, 2006; Churchland et al., 2012). In the proposed pattern generator for birdsong, the cortical nucleus HVC, the frequency and power of oscillatory bursting during singing increases with development (Crandall et al., 2007; Day et al., 2009). We examined the maturation of cellular activity patterns that underlie these changes. Single unit ensemble recording combined with antidromic identification (Day et al., 2011) was used to study network development in anesthetized zebra finches. Autocovariance quantified oscillations within single units. A subset of neurons oscillated in the theta/alpha/mu/beta range (8-20 Hz), with greater power in adults compared to juveniles. Across the network, the normalized oscillatory power in the 8-20 Hz range was greater in adults than juveniles. In addition, the correlated activity between rhythmic neuron pairs increased with development. We next examined the functional impact of the oscillators on the output neurons of HVC. We found that the firing of oscillatory neurons negatively correlated with the activity of cortico-basal ganglia neurons (HVC(X)s), which project to Area X (the song basal ganglia). If groups of oscillators work together to tonically inhibit and precisely control the spike timing of adult HVC(X)s with coordinated release from inhibition, then the activity of HVC(X)s in juveniles should be decreased relative to adults due to uncorrelated, tonic inhibition. Consistent with this hypothesis, HVC(X)s had lower activity in juveniles. These data reveal network changes that shape cortical-to-basal ganglia signaling during motor learning. PMID:23776169

Day, Nancy F; Nick, Teresa A

2013-10-01

140

Dopaminergic Mechanisms of Reduced Basal Ganglia Responses to Hedonic Reward During Interferon Alfa Administration  

PubMed Central

Context Inflammatory cytokines or cytokine inducers can alter basal ganglia activity, including reducing responsiveness to rewarding stimuli that may be mediated by cytokine effects on dopamine function. Objectives To determine whether long-term administration of the inflammatory cytokine interferon alfa reduces the basal ganglia response to reward and whether such changes are associated with decreased presynaptic striatal dopamine function and altered behavior. Design Cross-sectional and longitudinal studies. Setting Outpatient research unit and neuroimaging facilities at Emory University, Atlanta, Georgia. Patients Medically stable adults with chronic hepatitis C virus (HCV) infection eligible for interferon alfa treatment. Main Outcome Measures Neural activity in the ventral striatum during a hedonic reward task as measured by functional magnetic resonance imaging, uptake and turnover of radiolabeled fluorodopa F 18 (18F-dopa) in caudate and putamen using positron emission tomography, and interferon alfa–induced depression, anhedonia, fatigue, and neurotoxicity. Results Patients with HCV receiving interferon alfa for 4 to 6 weeks (n=14) exhibited significantly reduced bilateral activation of the ventral striatum in the win vs lose condition of a gambling task compared with patients with HCV awaiting interferon alfa treatment (n=14). Reduced activation of the ventral striatum was, in turn, significantly correlated with anhedonia, depression, and fatigue. In a separate longitudinal study, patients with HCV treated with interferon alfa for 4 to 6 weeks (n=12) exhibited significantly increased 18F-dopa uptake and decreased 18F-dopa turnover in caudate and putamen and in the same ventral striatal regions identified in the functional magnetic resonance imaging study. Baseline and percentage change in 18F-dopa uptake and turnover were correlated with behavioral alterations, including depression, fatigue, and neurotoxicity, during interferon alfa administration. Conclusions These data replicate and extend findings that inflammatory stimuli, including inflammatory cytokines, such as interferon alfa, alter basal ganglia activity and behavior in association with significant changes in presynaptic striatal dopamine function consistent with decreased dopamine synthesis or release. PMID:23026954

Capuron, Lucile; Pagnoni, Giuseppe; Drake, Daniel F.; Woolwine, Bobbi J.; Spivey, James R.; Crowe, Ronald J.; Votaw, John R.; Goodman, Mark M.; Miller, Andrew H.

2013-01-01

141

Association between a Novel Mutation in SLC20A2 and Familial Idiopathic Basal Ganglia Calcification  

PubMed Central

Familial idiopathic basal ganglia calcification (FIBGC) is a rare, autosomal dominant disorder involving bilateral calcification of the basal ganglia. To identify gene mutations related to a Chinese FIBGC lineage, we evaluated available individuals in the family using CT scans. DNA was extracted from the peripheral blood of available family members, and both exonic and flanking intronic sequences of the SLC20A2 gene were amplified by PCR and then sequenced. Non-denaturing polyacrylamide gel electrophoresis (PAGE) was used to confirm the presence of mutations. Allele imbalances of the SLC20A2 gene or relative quantity of SLC20A2 transcripts were evaluated using qRT-PCR. A novel heterozygous single base-pair deletion (c.510delA) within the SLC20A2 gene was identified. This deletion mutation was found to co-segregate with basal ganglia calcification in all of the affected family members but was not detected in unaffected individuals or in 167 unrelated Han Chinese controls. The mutation will cause a frameshift, producing a truncated SLC20A2 protein with a premature termination codon, most likely leading to the complete loss of function of the SLC20A2 protein. This mutation may also lead to a reduction in SLC20A2 mRNA expression by approximately 30% in cells from affected individuals. In conclusion, we identified a novel mutation in SLC20A2 that is linked to FIBGC. In addition to the loss of function at the protein level, decreasing the expression of SLC20A2 mRNA may be another mechanism that can regulate SLC20A2 function in IBGC individuals. We propose that the regional expression pattern of SLC20A1 and SLC20A2 might explain the unique calcification pattern observed in FIBGC patients. PMID:23437308

Zhang, Yang; Guo, Xianan; Wu, Anhua

2013-01-01

142

Mutations in SLC20A2 link familial idiopathic basal ganglia calcification with phosphate homeostasis.  

PubMed

Familial idiopathic basal ganglia calcification (IBGC) is a genetic condition with a wide spectrum of neuropsychiatric symptoms, including parkinsonism and dementia. Here, we identified mutations in SLC20A2, encoding the type III sodium-dependent phosphate transporter 2 (PiT2), in IBGC-affected families of varied ancestry, and we observed significantly impaired phosphate transport activity for all assayed PiT2 mutants in Xenopus laevis oocytes. Our results implicate altered phosphate homeostasis in the etiology of IBGC. PMID:22327515

Wang, Cheng; Li, Yulei; Shi, Lei; Ren, Jie; Patti, Monica; Wang, Tao; de Oliveira, João R M; Sobrido, María-Jesús; Quintáns, Beatriz; Baquero, Miguel; Cui, Xiaoniu; Zhang, Xiang-Yang; Wang, Lianqing; Xu, Haibo; Wang, Junhan; Yao, Jing; Dai, Xiaohua; Liu, Juan; Zhang, Lu; Ma, Hongying; Gao, Yong; Ma, Xixiang; Feng, Shenglei; Liu, Mugen; Wang, Qing K; Forster, Ian C; Zhang, Xue; Liu, Jing-Yu

2012-03-01

143

Functional correlates of exaggerated oscillatory activity in basal ganglia output in hemiparkinsonian rats.  

PubMed

Exaggerated beta range (13-30Hz) synchronized activity is observed in the basal ganglia of Parkinson's disease (PD) patients during implantation of deep brain stimulation electrodes and is thought to contribute to the motor symptoms of this disorder. To explore the translational potential of similar activity observed in a rat model of PD, local field potentials (LFPs) and spiking activity in basal ganglia output were characterized in rats with unilateral dopamine cell lesion during a range of behaviors. A circular treadmill was used to assess activity during walking; hemiparkinsonian rats could maintain a steady gait when oriented ipsiversive to the lesioned hemisphere, but were less effective at walking when oriented contraversive to lesion. Dramatic increases in substantia nigra pars reticulata (SNpr) LFP oscillatory activity and spike-LFP synchronization were observed within the beta/low gamma range (12-40Hz) in the lesioned hemisphere, relative to the non-lesioned hemisphere, with the dominant frequency of spike-LFP entrainment and LFP power varying with behavioral state. At 3weeks postlesion, the mean dominant entrainment frequency during ipsiversive treadmill walking and grooming was 34Hz. Other behaviors were associated with lower mean entrainment frequencies: 27-28Hz during alert non-walking and REM, 17Hz during rest and 21Hz during urethane anesthesia with sensory stimulation. SNpr spike-LFP entrainment frequency was stable during individual treadmill walking epochs, but increased gradually over weeks postlesion. In contrast, SNpr LFP power in the 25-40Hz range was greatest at the initiation of each walking epoch, and decreased during walking to stabilize by 6min at 49% of initial values. Power was further modulated in conjunction with the 1.5s stepping rhythm. Administration of l-dopa improved contraversive treadmill walking in correlation with a reduction in SNpr 25-40Hz LFP power and spike synchronization in the dopamine cell lesioned hemisphere. These effects were reversed by the serotonergic 1A agonist, 8-OH-DPAT. While the prominent spike-LFP phase locking observed during ongoing motor activity in the hemiparkinsonian rats occurs at frequencies intriguingly higher than in PD patients, the synchronized activity in the SNpr of this animal model has much in common with oscillatory activity recorded from the basal ganglia of the PD patients. Results support the potential of this model for providing insight into relationships between synchronization of basal ganglia output induced by loss of dopamine and motor symptoms in PD. PMID:25084518

Brazhnik, Elena; Novikov, Nikolay; McCoy, Alex J; Cruz, Ana V; Walters, Judith R

2014-11-01

144

What basal ganglia changes underlie the parkinsonian state? The significance of neuronal oscillatory activity  

PubMed Central

One well accepted functional feature of the parkinsonian state is the recording of enhanced beta oscillatory activity in the basal ganglia. This has been demonstrated in patients with Parkinson's disease (PD) and in animal models such as the rat with 6-hydroxydopamine (6-OHDA)-induced lesion and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated monkeys, all of which are associated with severe striatal dopamine depletion. Neuronal hyper-synchronization in the beta (or any other) band is not present despite the presence of bradykinetic features in the rat and monkey models, suggesting that increased beta band power may arise when nigro-striatal lesion is advanced and that it is not an essential feature of the early parkinsonian state. Similar observations and conclusions have been previously made for increased neuronal firing rate in the subthalamic and globus pallidus pars interna nuclei. Accordingly, it is suggested that early parkinsonism may be associated with dynamic changes in basal ganglia output activity leading to reduced movement facilitation that may be an earlier feature of the parkinsonian state. PMID:23727447

Quiroga-Varela, A.; Walters, J.R.; Brazhnik, E.; Marin, C.; Obeso, J.A.

2014-01-01

145

Mutations in SLC20A2 are a major cause of familial idiopathic basal ganglia calcification.  

PubMed

Familial idiopathic basal ganglia calcification (IBGC) or Fahr's disease is a rare neurodegenerative disorder characterized by calcium deposits in the basal ganglia and other brain regions, which is associated with neuropsychiatric and motor symptoms. Familial IBGC is genetically heterogeneous and typically transmitted in an autosomal dominant fashion. We performed a mutational analysis of SLC20A2, the first gene found to cause IBGC, to assess its genetic contribution to familial IBGC. We recruited 218 subjects from 29 IBGC-affected families of varied ancestry and collected medical history, neurological exam, and head CT scans to characterize each patient's disease status. We screened our patient cohort for mutations in SLC20A2. Twelve novel (nonsense, deletions, missense, and splice site) potentially pathogenic variants, one synonymous variant, and one previously reported mutation were identified in 13 families. Variants predicted to be deleterious cosegregated with disease in five families. Three families showed nonsegregation with clinical disease of such variants, but retrospective review of clinical and neuroimaging data strongly suggested previous misclassification. Overall, mutations in SLC20A2 account for as many as 41% of our familial IBGC cases. Our screen in a large series expands the catalog of SLC20A2 mutations identified to date and demonstrates that mutations in SLC20A2 are a major cause of familial IBGC. Non-perfect segregation patterns of predicted deleterious variants highlight the challenges of phenotypic assessment in this condition with highly variable clinical presentation. PMID:23334463

Hsu, Sandy Chan; Sears, Renee L; Lemos, Roberta R; Quintáns, Beatriz; Huang, Alden; Spiteri, Elizabeth; Nevarez, Lisette; Mamah, Catherine; Zatz, Mayana; Pierce, Kerrie D; Fullerton, Janice M; Adair, John C; Berner, Jon E; Bower, Matthew; Brodaty, Henry; Carmona, Olga; Dobrici?, Valerija; Fogel, Brent L; García-Estevez, Daniel; Goldman, Jill; Goudreau, John L; Hopfer, Suellen; Jankovi?, Milena; Jaumà, Serge; Jen, Joanna C; Kirdlarp, Suppachok; Klepper, Joerg; Kosti?, Vladimir; Lang, Anthony E; Linglart, Agnès; Maisenbacher, Melissa K; Manyam, Bala V; Mazzoni, Pietro; Miedzybrodzka, Zofia; Mitarnun, Witoon; Mitchell, Philip B; Mueller, Jennifer; Novakovi?, Ivana; Paucar, Martin; Paulson, Henry; Simpson, Sheila A; Svenningsson, Per; Tuite, Paul; Vitek, Jerrold; Wetchaphanphesat, Suppachok; Williams, Charles; Yang, Michele; Schofield, Peter R; de Oliveira, João R M; Sobrido, María-Jesús; Geschwind, Daniel H; Coppola, Giovanni

2013-02-01

146

The role of the basal ganglia and cerebellum in language processing  

PubMed Central

The roles of the cerebellum and basal ganglia have typically been confined in the literature to motor planning and control. However, mounting evidence suggests that these structures are involved in more cognitive domains such as language processing. In the current study, we looked at effective connectivity (the influence that one brain region has on another) of the cerebellum and basal ganglia with regions thought to be involved in phonological processing, i.e. left inferior frontal gyrus and left lateral temporal cortex. We analyzed functional magnetic resonance imaging data (fMRI) obtained during a rhyming judgment task in adults using dynamic causal modeling (DCM). The results showed that the cerebellum has reciprocal connections with both left inferior frontal gyrus and left lateral temporal cortex, whereas the putamen has unidirectional connections into these two brain regions. Furthermore, the connections between cerebellum and these phonological processing areas were stronger than the connections between putamen and these areas. This pattern of results suggests that the putamen and cerebellum may have distinct roles in language processing. Based on research in the motor planning and control literature, we argue that the putamen engages in cortical initiation while the cerebellum amplifies and refines this signal to facilitate correct decision making. PMID:17189619

Booth, James R.; Wood, Lydia; Lu, Dong; Houk, James C.; Bitan, Tali

2007-01-01

147

Neurotensin receptor binding levels in basal ganglia are not altered in Huntington's chorea or schizophrenia  

SciTech Connect

Autoradiographic techniques were used to examine the distribution and levels of neurotensin receptor binding sites in the basal ganglia and related regions of the human brain. Monoiodo ({sup 125}I-Tyr3)neurotensin was used as a ligand. High amounts of neurotensin receptor binding sites were found in the substantia nigra pars compacta. Lower but significant quantities of neurotensin receptor binding sites characterized the caudate, putamen, and nucleus accumbens, while very low quantities were seen in both medial and lateral segments of the globus pallidus. In Huntington's chorea, the levels of neurotensin receptor binding sites were found to be comparable to those of control cases. Only slight but not statistically significant decreases in amounts of receptor binding sites were detected in the dorsal part of the head and in the body of caudate nucleus. No alterations in the levels of neurotensin receptor binding sites were observed in the substantia nigra pars compacta and reticulata. These results suggest that a large proportion of neurotensin receptor binding sites in the basal ganglia are located on intrinsic neurons and on extrinsic afferent fibers that do not degenerate in Huntington's disease.

Palacios, J.M.; Chinaglia, G.; Rigo, M.; Ulrich, J.; Probst, A. (Sandoz Pharma Ltd., Basel (Switzerland))

1991-02-01

148

DARPP-32 to quantify intracerebral hemorrhage-induced neuronal death in basal ganglia.  

PubMed

Quantification of acute brain injury in basal ganglia is essential for mechanistic and therapeutic studies in experimental intracerebral hemorrhage (ICH). Using conventional counting of degenerating cells based on morphological or immunohistochemical criteria, it is hard to define the boundary of the whole lesion area. Dopamine- and cAMP-regulated phosphoprotein, Mr 32 kDa (DARPP-32) is a cytosolic protein highly enriched in medium-sized spiny neurons of the striatum. We developed new methods for quantifying lesion area by detecting the difference of the DARPP-32 negative area and the hematoma clot, and by measuring DARPP-32 protein level for semi-qualification in rat model of ICH. We found that DARPP-32 negative area around hematoma was present at day-1, peaked at day-3, and decreased at day-14 after ICH, a time course paralleled by DARPP-32 Western blots. The DARPP-32 negative area matched well with the necrotic area determined using propidium iodide. Treatment with an iron chelator, deferoxamine, attenuated the ICH-induced reduction in DARPP-32 protein levels. These results suggest that DARPP-32 is a simple and quantifiable indicator of ICH-induced neuronal death in basal ganglia. PMID:23543809

Jin, Hang; Xi, Guohua; Keep, Richard F; Wu, Jiang; Hua, Ya

2013-02-01

149

Basal Ganglia Neuronal Activity during Scanning Eye Movements in Parkinson’s Disease  

PubMed Central

The oculomotor role of the basal ganglia has been supported by extensive evidence, although their role in scanning eye movements is poorly understood. Nineteen Parkinso?s disease patients, which underwent implantation of deep brain stimulation electrodes, were investigated with simultaneous intraoperative microelectrode recordings and single channel electrooculography in a scanning eye movement task by viewing a series of colored pictures selected from the International Affective Picture System. Four patients additionally underwent a visually guided saccade task. Microelectrode recordings were analyzed selectively from the subthalamic nucleus, substantia nigra pars reticulata and from the globus pallidus by the WaveClus program which allowed for detection and sorting of individual neurons. The relationship between neuronal firing rate and eye movements was studied by crosscorrelation analysis. Out of 183 neurons that were detected, 130 were found in the subthalamic nucleus, 30 in the substantia nigra and 23 in the globus pallidus. Twenty percent of the neurons in each of these structures showed eye movement-related activity. Neurons related to scanning eye movements were mostly unrelated to the visually guided saccades. We conclude that a relatively large number of basal ganglia neurons are involved in eye motion control. Surprisingly, neurons related to scanning eye movements differed from neurons activated during saccades suggesting functional specialization and segregation of both systems for eye movement control. PMID:24223158

Sieger, Tomáš; Bonnet, Cecilia; Serranová, Tereza; Wild, Ji?í; Novák, Daniel; R?ži?ka, Filip; Urgošík, Dušan; R?ži?ka, Evžen; Gaymard, Bertrand; Jech, Robert

2013-01-01

150

Mutations in SLC20A2 are a major cause of familial idiopathic basal ganglia calcification  

PubMed Central

Familial idiopathic basal ganglia calcification (IBGC) or Fahr’s disease is a rare neurodegenerative disorder characterized by calcium deposits in the basal ganglia and other brain regions, which is associated with neuropsychiatric and motor symptoms. Familial IBGC is genetically heterogeneous and typically transmitted in an autosomal dominant fashion. We performed a mutational analysis of SLC20A2, the first gene found to cause IBGC, to assess its genetic contribution to familial IBGC. We recruited 218 subjects from 29 IBGC-affected families of varied ancestry and collected medical history, neurological exam, and head CT scans to characterize each patient’s disease status. We screened our patient cohort for mutations in SLC20A2. Twelve novel (nonsense, deletions, missense, and splice site) potentially pathogenic variants, one synonymous variant, and one previously reported mutation were identified in 13 families. Variants predicted to be deleterious cosegregated with disease in five families. Three families showed nonsegregation with clinical disease of such variants, but retrospective review of clinical and neuroimaging data strongly suggested previous misclassification. Overall, mutations in SLC20A2 account for as many as 41 % of our familial IBGC cases. Our screen in a large series expands the catalog of SLC20A2 mutations identified to date and demonstrates that mutations in SLC20A2 are a major cause of familial IBGC. Non-perfect segregation patterns of predicted deleterious variants highlight the challenges of phenotypic assessment in this condition with highly variable clinical presentation. PMID:23334463

Hsu, Sandy Chan; Sears, Renee L.; Lemos, Roberta R.; Quintáns, Beatriz; Huang, Alden; Spiteri, Elizabeth; Nevarez, Lisette; Mamah, Catherine; Zatz, Mayana; Pierce, Kerrie D.; Fullerton, Janice M.; Adair, John C.; Berner, Jon E.; Bower, Matthew; Brodaty, Henry; Carmona, Olga; Dobrici?, Valerija; Fogel, Brent L.; García-Estevez, Daniel; Goldman, Jill; Goudreau, John L.; Hopfer, Suellen; Jankovi?, Milena; Jaumà, Serge; Jen, Joanna C.; Kirdlarp, Suppachok; Klepper, Joerg; Kosti?, Vladimir; Lang, Anthony E.; Linglart, Agnès; Maisenbacher, Melissa K.; Manyam, Bala V.; Mazzoni, Pietro; Miedzybrodzka, Zofia; Mitarnun, Witoon; Mitchell, Philip B.; Mueller, Jennifer; Novakovi?, Ivana; Paucar, Martin; Paulson, Henry; Simpson, Sheila A.; Svenningsson, Per; Tuite, Paul; Vitek, Jerrold; Wetchaphanphesat, Suppachok; Williams, Charles; Yang, Michele; Schofield, Peter R.; de Oliveira, João R. M.; Sobrido, María-Jesús

2014-01-01

151

Basal ganglia hyperintensity on T1-weighted imaging of a patient with central nervous system metastasis producing carcinoembryonic antigens.  

PubMed

We herein report unusual basal ganglia hyperintense lesions on noncontrast T1-weighted magnetic resonance imaging in a patient with central nervous system metastasis from lung adenocarcinoma that was treated with gefitinib. T2*-weighted magnetic resonance imaging showed no hypointense lesions, thereby excluding the possibility of calcification or haemorrhage. A stereotactic brain biopsy of the left basal ganglia lesions revealed atypical cells, some of which formed a glandular lumen with a micropapillary pattern. These cells were immunopositive for markers of lung adenocarcinoma, thereby confirming the diagnosis of metastasis. We speculate that proteins, including carcinoembryonic antigens from the adenocarcinoma cells in the basal ganglia, may have contributed to the hyperintensity observed on noncontrast T1-weighted magnetic resonance imaging. PMID:23370750

Fujita, Koji; Sakai, Waka; Harada, Masafumi; Sakaki, Mika; Mure, Hideo; Nagahiro, Shinji; Izumi, Yuishin; Kaji, Ryuji

2013-01-01

152

Analysis of candidate genes at the IBGC1 locus associated with idiopathic basal ganglia calcification ("Fahr's disease").  

PubMed

Basal ganglia calcification (striatopallidodentate calcifications) can be caused by several systemic and neurological disorders. Familial Idiopathic Basal Ganglia Calcification (IBGC, "Fahr's disease"), is characterized by basal ganglia and extrabasal ganglia calcifications, parkinsonism and neuropsychiatric symptoms. Because of an increased use of neuroimaging procedures, calcifications of the basal ganglia are visualized more often and precociously. In 1999, a major American family with IBGC was linked to a locus on chromosome 14q (IBGC1). Another small kindred, from Spain, has also been reported as possibly linked to this locus. Here we report the main findings of the first 30 candidate genes sequenced at the IBGC1 locus during the process of searching for a mutation responsible for familial IBGC. During the sequencing process, we identified a heterozygous nonsynonymous single nucleotide polymorphism (exon 20 of the MGEA6/c-TAGE gene) shared by the affected and not present in the controls. This SNP was randomly screened in the general population (348 chromosomes) in a minor allele frequency to 0.0058 (two heterozygous among 174 subjects). Another variation in this gene, in the exon 9, was found in the Spanish family. However, this variation was extremely common in the general population. Functional and population studies are necessary to fully access the implications of the MGEA6 gene in familial IBGC, and a complete sequencing of the IBGC1 locus will be necessary to define a gene responsible for familial IBGC. PMID:17917073

Oliveira, J R M; Sobrido, M J; Spiteri, E; Hopfer, S; Meroni, G; Petek, E; Baquero, M; Geschwind, D H

2007-01-01

153

Using a hybrid neuron in physiologically inspired models of the basal ganglia  

PubMed Central

Our current understanding of the basal ganglia (BG) has facilitated the creation of computational models that have contributed novel theories, explored new functional anatomy and demonstrated results complementing physiological experiments. However, the utility of these models extends beyond these applications. Particularly in neuromorphic engineering, where the basal ganglia's role in computation is important for applications such as power efficient autonomous agents and model-based control strategies. The neurons used in existing computational models of the BG, however, are not amenable for many low-power hardware implementations. Motivated by a need for more hardware accessible networks, we replicate four published models of the BG, spanning single neuron and small networks, replacing the more computationally expensive neuron models with an Izhikevich hybrid neuron. This begins with a network modeling action-selection, where the basal activity levels and the ability to appropriately select the most salient input is reproduced. A Parkinson's disease model is then explored under normal conditions, Parkinsonian conditions and during subthalamic nucleus deep brain stimulation (DBS). The resulting network is capable of replicating the loss of thalamic relay capabilities in the Parkinsonian state and its return under DBS. This is also demonstrated using a network capable of action-selection. Finally, a study of correlation transfer under different patterns of Parkinsonian activity is presented. These networks successfully captured the significant results of the originals studies. This not only creates a foundation for neuromorphic hardware implementations but may also support the development of large-scale biophysical models. The former potentially providing a way of improving the efficacy of DBS and the latter allowing for the efficient simulation of larger more comprehensive networks. PMID:23847524

Thibeault, Corey M.; Srinivasa, Narayan

2013-01-01

154

Pure hemidystonia with basal ganglion abnormalities on positron emission tomography  

SciTech Connect

We present a patient with hemidystonia and an abnormality of the contralateral basal ganglion seen only with positron emission tomography. A 50-year-old sinistral man suffered minor trauma to the right side of his head and neck. Within 20 minutes he developed paroxysmal intermittent dystonic posturing of his right face, forearm, hand, and foot, with weaker contractions of the left foot, lasting several seconds and recurring every few minutes. Neurological findings between spells were normal. The following were also normal: electrolyte, calcium, magnesium, and arterial blood gas levels, and findings of drug screen, cerebrospinal fluid examination, electroencephalography with nasopharyngeal leads, computed tomographic scanning (initially and four weeks later), and cerebral angiography. Positron emission tomographic scanning revealed abnormalities in the left basal ganglion region, including decreased oxygen metabolism, decreased oxygen extraction, increased blood volume, and increased blood flow.

Perlmutter, J.S.; Raichle, M.E.

1984-03-01

155

Past, Present, and Future of the Pathophysiological Model of the Basal Ganglia  

PubMed Central

The current model of basal ganglia (BG) was introduced two decades ago and has settled most of our current understanding of BG function and dysfunction. Extensive research efforts have been carried out in recent years leading to further refinement and understanding of the normal and diseased BG. Several questions, however, are yet to be resolved. This short review provides a synopsis of the evolution of thought regarding the pathophysiological model of the BG and summarizes the main recent findings and additions to this field of research. We have also tried to identify major challenges that need to be addressed and resolved in the near future. Detailed accounts and state-of-the-art developments concerning research on the BG are provided in the articles that make up this Special Issue. PMID:21808607

Obeso, José A.; Lanciego, José L.

2011-01-01

156

Different susceptibility of medial temporal lobe and basal ganglia atrophy rates to vascular risk factors  

PubMed Central

Atrophy of medial temporal lobe (MTL) and basal ganglia (BG) are characteristic of various neurodegenerative diseases in older people. In search of potentially modifiable factors that lead to atrophy in these structures, we studied the association of vascular risk factors to atrophy of MTL and BG in 368 non-demented men and women [b. 1907–1935] who participated in the Age, Gene/Environment, Susceptibility - Reykjavik Study. A fully automated segmentation pipeline estimated volumes of MTL and BG from whole brain MRI performed at baseline and 2.4 years later. Linear regression models showed higher systolic and diastolic blood pressures and the presence of Apo E ?4 were independently associated with increased atrophy of MTL but no association of vascular risk factors with atrophy of BG. The different susceptibility of MTL and BG atrophy to the presence of vascular risk factors suggests the relatively preserved perfusion of BG when vascular risk factors are present. PMID:23992618

de Jong, Laura W.; Forsberg, Lars E.; Vidal, Jean-Sébastien; Sigurdsson, Sigurdur; Zijdenbos, Alex P.; Garcia, Melissa; Eiriksdottir, Gudny; Gudnason, Vilmundur; van Buchem, Mark A.; Launer, Lenore J.

2013-01-01

157

The highs and lows of beta activity in cortico-basal ganglia loops  

PubMed Central

Oscillatory activity in the beta (13–30 Hz) frequency band is widespread in cortico-basal ganglia circuits, and becomes prominent in Parkinson's disease (PD). Here we develop the hypothesis that the degree of synchronization in this frequency band is a critical factor in gating computation across a population of neurons, with increases in beta band synchrony entailing a loss of information-coding space and hence computational capacity. Task and context drive this dynamic gating, so that for each state there will be an optimal level of network synchrony, and levels lower or higher than this will impair behavioural performance. Thus, both the pathological exaggeration of synchrony, as observed in PD, and the ability of interventions like deep brain stimulation (DBS) to excessively suppress synchrony can potentially lead to impairments in behavioural performance. Indeed, under physiological conditions, the manipulation of computational capacity by beta activity may itself present a mechanism of action selection and maintenance. PMID:24890470

Brittain, John-Stuart; Sharott, Andrew; Brown, Peter

2014-01-01

158

The basal ganglia is necessary for learning spectral, but not temporal features of birdsong  

PubMed Central

Executing a motor skill requires the brain to control which muscles to activate at what times. How these aspects of control - motor implementation and timing - are acquired, and whether the learning processes underlying them differ, is not well understood. To address this we used a reinforcement learning paradigm to independently manipulate both spectral and temporal features of birdsong, a complex learned motor sequence, while recording and perturbing activity in underlying circuits. Our results uncovered a striking dissociation in how neural circuits underlie learning in the two domains. The basal ganglia was required for modifying spectral, but not temporal structure. This functional dissociation extended to the descending motor pathway, where recordings from a premotor cortex analogue nucleus reflected changes to temporal, but not spectral structure. Our results reveal a strategy in which the nervous system employs different and largely independent circuits to learn distinct aspects of a motor skill. PMID:24075977

Ali, Farhan; Fantana, Antoniu L.; Burak, Yoram; Ölveczky, Bence P.

2013-01-01

159

Metabolic activity of the basal ganglia in parkinsonian syndromes in human and non-human primates: A cytochrome oxidase histochemistry study  

Microsoft Academic Search

In order to examine the consequences of nigrostriatal denervation on metabolic and functional activity of the basal ganglia, we analysed the distribution of cytochrome oxidase, a metabolic marker for neuronal functional activity, throughout the different basal ganglia structures in parkinsonian syndromes. The study was performed using enzyme histochemistry and densitometric measurements in patients with Parkinson's disease and in monkeys rendered

M. Vila; R. Levy; M.-T. Herrero; B. Faucheux; J. A. Obeso; Y. Agid; E. C. Hirsch

1996-01-01

160

Modeling the Contributions of Basal Ganglia and Hippocampus to Spatial Navigation Using Reinforcement Learning  

PubMed Central

A computational neural model that describes the competing roles of Basal Ganglia and Hippocampus in spatial navigation is presented. Model performance is evaluated on a simulated Morris water maze explored by a model rat. Cue-based and place-based navigational strategies, thought to be subserved by the Basal ganglia and Hippocampus respectively, are described. In cue-based navigation, the model rat learns to directly head towards a visible target, while in place-based navigation the target position is represented in terms of spatial context provided by an array of poles placed around the pool. Learning is formulated within the framework of Reinforcement Learning, with the nigrostriatal dopamine signal playing the role of Temporal Difference Error. Navigation inherently involves two apparently contradictory movements: goal oriented movements vs. random, wandering movements. The model hypothesizes that while the goal-directedness is determined by the gradient in Value function, randomness is driven by the complex activity of the SubThalamic Nucleus (STN)-Globus Pallidus externa (GPe) system. Each navigational system is associated with a Critic, prescribing actions that maximize value gradients for the corresponding system. In the integrated system, that incorporates both cue-based and place-based forms of navigation, navigation at a given position is determined by the system whose value function is greater at that position. The proposed model describes the experimental results of [1], a lesion-study that investigates the competition between cue-based and place-based navigational systems. The present study also examines impaired navigational performance under Parkinsonian-like conditions. The integrated navigational system, operated under dopamine-deficient conditions, exhibits increased escape latency as was observed in experimental literature describing MPTP model rats navigating a water maze. PMID:23110073

Sukumar, Deepika; Rengaswamy, Maithreye; Chakravarthy, V. Srinivasa

2012-01-01

161

SLC20A2 and THAP1 deletion in familial basal ganglia calcification with dystonia.  

PubMed

Idiopathic basal ganglia calcification (IBGC) is characterized by bilateral calcification of the basal ganglia associated with a spectrum of neuropsychiatric and motor syndromes. In this study, we set out to determine the frequency of the recently identified IBGC gene SLC20A2 in 27 IBGC cases from the Mayo Clinic Florida Brain Bank using both Sanger sequencing and TaqMan copy number analysis to cover the complete spectrum of possible mutations. We identified SLC20A2 pathogenic mutations in two of the 27 cases of IBGC (7 %). Sequencing analysis identified a p.S113* nonsense mutation in SLC20A2 in one case. TaqMan copy number analysis of SLC20A2 further revealed a genomic deletion in a second case, which was part of a large previously reported Canadian IBGC family with dystonia. Subsequent whole-genome sequencing in this family revealed a 563,256-bp genomic deletion with precise breakpoints on chromosome 8 affecting multiple genes including SLC20A2 and the known dystonia-related gene THAP1. The deletion co-segregated with disease in all family members. The deletion of THAP1 in addition to SLC20A2 in the Canadian IBGC family may contribute to the severe and early onset dystonia in this family. The identification of an SLC20A2 genomic deletion in a familial form of IBGC demonstrates that reduced SLC20A2 in the absence of mutant protein is sufficient to cause neurodegeneration and that previously reported SLC20A2 mutation frequencies may be underestimated. PMID:24135862

Baker, Matt; Strongosky, Audrey J; Sanchez-Contreras, Monica Y; Yang, Shan; Ferguson, Will; Calne, Donald B; Calne, Susan; Stoessl, A Jon; Allanson, Judith E; Broderick, Daniel F; Hutton, Michael L; Dickson, Dennis W; Ross, Owen A; Wszolek, Zbigniew K; Rademakers, Rosa

2014-03-01

162

Efferent connections of the "olfactostriatum": a specialized vomeronasal structure within the basal ganglia of snakes.  

PubMed

The olfactostriatum is a portion of the basal ganglia of snakes that receives substantial vomeronasal afferents through projections from the nucleus sphericus. In a preceding article, the olfactostriatum of garter snakes (Thamnophis sirtalis) was characterized on the basis of chemoarchitecture (distribution of serotonin, neuropeptide Y and tyrosine hydroxylase) and pattern of afferent connections [Martinez-Marcos, A., Ubeda-Banon, I., Lanuza, E., Halpern, M., 2005. Chemoarchitecture and afferent connections of the "olfactostriatum": a specialized vomeronasal structure within the basal ganglia of snakes. J. Chem. Neuroanat. 29, 49-69]. In the present study, its efferent connections have been investigated. The olfactostriatum projects to the main and accessory olfactory bulbs, lateral cortex, septal complex, ventral pallidum, external, ventral anterior and dorsolateral amygdalae, bed nucleus of the stria terminalis, preoptic area, lateral posterior hypothalamic nucleus, ventral tegmental area, substantia nigra and raphe nuclei. Tracer injections in the nucleus accumbens proper, a structure closely associated with the olfactostriatum, result in a similar pattern of efferent connections with the exception of those reaching the main and accessory olfactory bulbs, lateral cortex, external, ventral anterior and dorsolateral amygdalae and bed nucleus of the stria terminalis. These data, therefore, help to characterize the olfactostriatum, an apparently specialized area of the nucleus accumbens. Double labeling experiments after tracer injections in the nucleus sphericus and the lateral posterior hypothalamic nucleus demonstrate a pathway between these two structures through the olfactostriatum. Injections in the olfactostriatum and in the medial amygdala show parallel projections to the lateral posterior hypothalamic nucleus. Since this hypothalamic nucleus has been previously described as projecting to the hypoglossal nucleus, both, the medial amygdala and the olfactostriatum may mediate vomeronasal influence on tongue-flick behavior. PMID:15820623

Martinez-Marcos, Alino; Ubeda-Bañon, Isabel; Lanuza, Enrique; Halpern, Mimi

2005-05-01

163

Mechanism of parkinsonian neuronal oscillations in the primate basal ganglia: some considerations based on our recent work  

PubMed Central

Accumulating evidence suggests that abnormal neuronal oscillations in the basal ganglia (BG) contribute to the manifestation of parkinsonian symptoms. In this article, we would like to summarize our recent work on the mechanism underlying abnormal oscillations in the parkinsonian state and discuss its significance in pathophysiology of Parkinson’s disease. We recorded neuronal activity in the BG of parkinsonian monkeys treated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine. Systemic administration of L-DOPA alleviated parkinsonian motor signs and decreased abnormal neuronal oscillations (8–15 Hz) in the internal (GPi) and external (GPe) segments of the globus pallidus and the subthalamic nucleus (STN). Inactivation of the STN by muscimol (GABAA receptor agonist) injection also ameliorated parkinsonian signs and suppressed GPi oscillations. The blockade of glutamatergic inputs to the STN by local microinjection of a mixture of 3-(2-carboxypiperazin-4-yl)-propyl-1-phosphonic acid (glutamatergic NMDA receptor antagonist) and 1,2,3,4-tetrahydro-6-nitro-2,3-dioxo-benzo[f]quinoxaline-7-sulfonamide (glutamatergic AMPA/kainate receptor antagonist) suppressed neuronal oscillations in the STN. STN oscillations were also attenuated by the blockade of GABAergic neurotransmission from the GPe to the STN by muscimol inactivation of the GPe. These results suggest that cortical glutamatergic inputs to the STN and reciprocal GPe-STN interconnections are both important for the generation and amplification of the oscillatory activity of GPe and STN neurons in the parkinsonian state. The oscillatory activity in the STN is subsequently transmitted to the GPi and may contribute to manifestation of parkinsonian symptoms. PMID:24904309

Nambu, Atsushi; Tachibana, Yoshihisa

2014-01-01

164

Basal Ganglia Structures Differentially Contribute to Verbal Fluency: Evidence from Human Immunodeficiency Virus (HIV)-Infected Adults  

ERIC Educational Resources Information Center

Background: The basal ganglia (BG) are involved in executive language functions (i.e., verbal fluency) through their connections with cortical structures. The caudate and putamen receive separate inputs from prefrontal and premotor cortices, and may differentially contribute to verbal fluency performance. We examined BG integrity in relation to…

Thames, April D.; Foley, Jessica M.; Wright, Matthew J.; Panos, Stella E.; Ettenhofer, Mark; Ramezani, Amir; Streiff, Vanessa; El-Saden, Suzie; Goodwin, Scott; Bookheimer, Susan Y.; Hinkin, Charles H.

2012-01-01

165

Basal Ganglia, Dopamine and Temporal Processing: Performance on Three Timing Tasks on and off Medication in Parkinson's Disease  

ERIC Educational Resources Information Center

A pervasive hypothesis in the timing literature is that temporal processing in the milliseconds and seconds range engages the basal ganglia and is modulated by dopamine. This hypothesis was investigated by testing 12 patients with Parkinson's disease (PD), both "on" and "off" dopaminergic medication, and 20 healthy controls on three timing tasks.…

Jones, Catherine R. G.; Malone, Tim J. L.; Dirnberger, Georg; Edwards, Mark; Jahanshahi, Marjan

2008-01-01

166

The Role of Inhibition in Generating and Controlling Parkinson’s Disease Oscillations in the Basal Ganglia  

PubMed Central

Movement disorders in Parkinson’s disease (PD) are commonly associated with slow oscillations and increased synchrony of neuronal activity in the basal ganglia. The neural mechanisms underlying this dynamic network dysfunction, however, are only poorly understood. Here, we show that the strength of inhibitory inputs from striatum to globus pallidus external (GPe) is a key parameter controlling oscillations in the basal ganglia. Specifically, the increase in striatal activity observed in PD is sufficient to unleash the oscillations in the basal ganglia. This finding allows us to propose a unified explanation for different phenomena: absence of oscillation in the healthy state of the basal ganglia, oscillations in dopamine-depleted state and quenching of oscillations under deep-brain-stimulation (DBS). These novel insights help us to better understand and optimize the function of DBS protocols. Furthermore, studying the model behavior under transient increase of activity of the striatal neurons projecting to the indirect pathway, we are able to account for both motor impairment in PD patients and for reduced response inhibition in DBS implanted patients. PMID:22028684

Kumar, Arvind; Cardanobile, Stefano; Rotter, Stefan; Aertsen, Ad

2011-01-01

167

Indirect basal ganglia pathway mediation of repetitive behavior: attenuation by adenosine receptor agonists.  

PubMed

Repetitive behaviors are diagnostic for autism and common in related neurodevelopmental disorders. Despite their clinical importance, underlying mechanisms associated with the expression of these behaviors remain poorly understood. Our lab has previously shown that the rates of spontaneous stereotypy in deer mice (Peromyscus maniculatus) were negatively correlated with enkephalin content, a marker of striatopallidal but not striatonigral neurons. To investigate further the role of the indirect basal ganglia pathway, we examined neuronal activation of the subthalamic nucleus (STN) using cytochrome oxidase (CO) histochemistry in high- and low-stereotypy mice. CO activity in STN was significantly lower in high-stereotypy mice and negatively correlated with the frequency of stereotypy. In addition, exposure to environmental enrichment, which attenuated stereotypy, normalized the activity of STN. Co-administration of the adenosine A(2A) receptor agonist CGS21680 and the A(1) receptor agonist CPA attenuated stereotypy dose-dependently. The significant reduction associated with the lowest dose of the drug combination tested was due to its effects on mice with lower baseline levels of stereotypy. Higher doses of the drug combination were required to show robust behavioral effects, and presumably requisite activation of the indirect pathway, in high-stereotypy mice. These findings support that decreased indirect pathway activity is linked to the expression of high levels of stereotypy in deer mice and that striatal A(1) and A(2A) receptors may provide promising therapeutic targets for the treatment of repetitive behaviors in neurodevelopmental disorders. PMID:20178817

Tanimura, Yoko; Vaziri, Sasha; Lewis, Mark H

2010-06-26

168

Disconnection of a basal ganglia circuit in juvenile songbirds attenuates the spectral differentiation of song syllables.  

PubMed

Similar to language acquisition by human infants, juvenile male zebra finches (Taeniopygia guttata) imitate an adult (tutor) song by transitioning from repetitive production of one or two undifferentiated protosyllables to the sequential production of a larger and spectrally heterogeneous set of syllables. The primary motor region that controls learned song is driven by a confluence of input from two premotor pathways: a posterior pathway that encodes the adult song syllables and an anterior pathway that includes a basal ganglia (BG)-thalamo-cortical circuit. Similar to mammalian motor-learning systems, the songbird BG circuit is thought to be necessary for shaping juvenile vocal behaviour (undifferentiated protosyllables) toward specific targets (the tutor's song syllables). Here, we tested the hypothesis that anterior pathway activity contributes to the process of protosyllable differentiation. Bilateral ablation of lateral magnocellular nucleus of the anterior nidopallium (LMAN) was used to disconnect BG circuitry at ages before protosyllable production and differentiation. Comparison to surgical controls revealed that protosyllables fail to differentiate in birds that received juvenile LMAN ablation--the adult songs of birds with >80% bilateral LMAN ablation consisted of only one or two syllables produced with the repetitive form and spectral structure that characterizes undifferentiated protosyllables in normal juveniles. Our findings support a role for BG circuitry in shaping juvenile vocal behaviour toward the acoustic structure of the tutor song and suggest that posterior pathway function remains in an immature "default" state when developmental interaction with the anterior pathway is reduced or eliminated. PMID:24218118

Elliott, Kevin C; Wu, Wei; Bertram, Richard; Johnson, Frank

2014-06-01

169

Prediction of immediate and future rewards differentially recruits cortico-basal ganglia loops.  

PubMed

Evaluation of both immediate and future outcomes of one's actions is a critical requirement for intelligent behavior. Using functional magnetic resonance imaging (fMRI), we investigated brain mechanisms for reward prediction at different time scales in a Markov decision task. When human subjects learned actions on the basis of immediate rewards, significant activity was seen in the lateral orbitofrontal cortex and the striatum. When subjects learned to act in order to obtain large future rewards while incurring small immediate losses, the dorsolateral prefrontal cortex, inferior parietal cortex, dorsal raphe nucleus and cerebellum were also activated. Computational model-based regression analysis using the predicted future rewards and prediction errors estimated from subjects' performance data revealed graded maps of time scale within the insula and the striatum: ventroanterior regions were involved in predicting immediate rewards and dorsoposterior regions were involved in predicting future rewards. These results suggest differential involvement of the cortico-basal ganglia loops in reward prediction at different time scales. PMID:15235607

Tanaka, Saori C; Doya, Kenji; Okada, Go; Ueda, Kazutaka; Okamoto, Yasumasa; Yamawaki, Shigeto

2004-08-01

170

Impaired Frontal-Basal Ganglia Connectivity in Adolescents with Internet Addiction  

PubMed Central

Understanding the neural basis of poor impulse control in Internet addiction (IA) is important for understanding the neurobiological mechanisms of this syndrome. The current study investigated how neuronal pathways implicated in response inhibition were affected in IA using a Go-Stop paradigm and functional magnetic resonance imaging (fMRI). Twenty-three control subjects aged 15.2 ± 0.5 years (mean ± S.D.) and eighteen IA subjects aged 15.1 ± 1.4 years were studied. Effective connectivity within the response inhibition network was quantified using (stochastic) dynamic causal modeling (DCM). The results showed that the indirect frontal-basal ganglia pathway was engaged by response inhibition in healthy subjects. However, we did not detect any equivalent effective connectivity in the IA group. This suggests the IA subjects fail to recruit this pathway and inhibit unwanted actions. This study provides a clear link between Internet addiction as a behavioral disorder and aberrant connectivity in the response inhibition network. PMID:24848380

Li, Baojuan; Friston, Karl J.; Liu, Jian; Liu, Yang; Zhang, Guopeng; Cao, Fenglin; Su, Linyan; Yao, Shuqiao; Lu, Hongbing; Hu, Dewen

2014-01-01

171

Towards an executive without a homunculus: computational models of the prefrontal cortex/basal ganglia system.  

PubMed

The prefrontal cortex (PFC) has long been thought to serve as an 'executive' that controls the selection of actions and cognitive functions more generally. However, the mechanistic basis of this executive function has not been clearly specified often amounting to a homunculus. This paper reviews recent attempts to deconstruct this homunculus by elucidating the precise computational and neural mechanisms underlying the executive functions of the PFC. The overall approach builds upon existing mechanistic models of the basal ganglia (BG) and frontal systems known to play a critical role in motor control and action selection, where the BG provide a 'Go' versus 'NoGo' modulation of frontal action representations. In our model, the BG modulate working memory representations in prefrontal areas to support more abstract executive functions. We have developed a computational model of this system that is capable of developing human-like performance on working memory and executive control tasks through trial-and-error learning. This learning is based on reinforcement learning mechanisms associated with the midbrain dopaminergic system and its activation via the BG and amygdala. Finally, we briefly describe various empirical tests of this framework. PMID:17428778

Hazy, Thomas E; Frank, Michael J; O'reilly, Randall C

2007-09-29

172

A de novo nonsense PDGFB mutation causing idiopathic basal ganglia calcification with laryngeal dystonia.  

PubMed

Idiopathic basal ganglia calcification (IBGC) is characterized by brain calcification and a wide variety of neurologic and psychiatric symptoms. In families with autosomal dominant inheritance, three causative genes have been identified: SLC20A2, PDGFRB, and, very recently, PDGFB. Whereas in clinical practice sporadic presentation of IBGC is frequent, well-documented reports of true sporadic occurrence are rare. We report the case of a 20-year-old woman who presented laryngeal dystonia revealing IBGC. Her healthy parents' CT scans were both normal. We identified in the proband a new nonsense mutation in exon 4 of PDGFB, c.439C>T (p.Gln147*), which was absent from the parents' DNA. This mutation may result in a loss-of-function of PDGF-B, which has been shown to cause IBGC in humans and to disrupt the blood-brain barrier in mice, resulting in brain calcification. The c.439C>T mutation is located between two previously reported nonsense mutations, c.433C>T (p.Gln145*) and c.445C>T (p.Arg149*), on a region that could be a hot spot for de novo mutations. We present the first full demonstration of the de novo occurrence of an IBGC-causative mutation in a sporadic case. PMID:24518837

Nicolas, Gaël; Jacquin, Agnès; Thauvin-Robinet, Christel; Rovelet-Lecrux, Anne; Rouaud, Olivier; Pottier, Cyril; Aubriot-Lorton, Marie-Hélène; Rousseau, Stéphane; Wallon, David; Duvillard, Christian; Béjot, Yannick; Frébourg, Thierry; Giroud, Maurice; Campion, Dominique; Hannequin, Didier

2014-10-01

173

PDGF, pericytes and the pathogenesis of idiopathic basal ganglia calcification (IBGC).  

PubMed

Platelet-derived growth factors (PDGFs) are important mitogens for various types of mesenchymal cells, and as such, they exert critical functions during organogenesis in mammalian embryonic and early postnatal development. Increased or ectopic PDGF activity may also cause or contribute to diseases such as cancer and tissue fibrosis. Until recently, no loss-of-function (LOF) mutations in PDGF or PDGF receptor genes were reported as causally linked to a human disease. This changed in 2013 when reports appeared on presumed LOF mutations in the genes encoding PDGF-B and its receptor PDGF receptor-beta (PDGF-R?) in familial idiopathic basal ganglia calcification (IBGC), a brain disease characterized by anatomically localized calcifications in or near the blood microvessels. Here, we review PDGF-B and PDGF-R? biology with special reference to their functions in brain-blood vessel development, pericyte recruitment and the regulation of the blood-brain barrier. We also discuss various scenarios for IBGC pathogenesis suggested by observations in patients and genetically engineered animal models of the disease. PMID:24946076

Betsholtz, Christer; Keller, Annika

2014-07-01

174

Novel SLC20A2 mutations identified in southern Chinese patients with idiopathic basal ganglia calcification.  

PubMed

Idiopathic basal ganglia calcification (IBGC) is a rare neuropsychiatric disorder characterized by bilateral and symmetric cerebral calcifications. Recently, SLC20A2 was identified as a causative gene for familial IBGC, and three mutations were reported in a northern Chinese population. Here, we aimed to explore the mutation spectrum of SLC20A2 in a southern Chinese population. Sanger sequencing was employed to screen mutations within SLC20A2 in two IBGC families and 14 sporadic IBGC cases from a southern Han Chinese population. Four novel mutations (c.82G>A p.D28N, c.185T>C p.L62P, c.1470_1478delGCAGGTCCT p.Q491_L493del and c.935-1G>A) were identified in two families and two sporadic cases, respectively; none were detected in 200 unrelated controls. No mutation was found in the remaining 12 patients. Different mutations may result in varied phenotypes, including brain calcification and clinical manifestations. Our study supports the hypothesis that SLC20A2 is a causative gene of IBGC and expands the mutation spectrum of SLC20A2, which facilitates the understanding of the genotype-phenotype correlation of IBGC. PMID:23939468

Chen, Wan-Jin; Yao, Xiang-Ping; Zhang, Qi-Jie; Ni, Wang; He, Jin; Li, Hong-Fu; Liu, Xin-Yi; Zhao, Gui-Xian; Murong, Shen-Xing; Wang, Ning; Wu, Zhi-Ying

2013-10-15

175

Idiopathic basal ganglia calcification-associated PDGFRB mutations impair the receptor signalling.  

PubMed

Platelet-derived growth factors (PDGF) bind to two related receptor tyrosine kinases, which are encoded by the PDGFRA and PDGFRB genes. Recently, heterozygous PDGFRB mutations have been described in patients diagnosed with idiopathic basal ganglia calcification (IBGC or Fahr disease), a rare inherited neurological disorder. The goal of the present study was to determine whether these mutations had a positive or negative impact on the PDGFRB activity. We first showed that the E1071V mutant behaved like wild-type PDGFRB and may represent a polymorphism unrelated to IBGC. In contrast, the L658P mutant had no kinase activity and failed to activate any of the pathways normally stimulated by PDGF. The R987W mutant activated Akt and MAP kinases but did not induce the phosphorylation of signal transducer and activator of transcription 3 (STAT3) after PDGF stimulation. Phosphorylation of phospholipase C? was also decreased. Finally, we showed that the R987W mutant was more rapidly degraded upon PDGF binding compared to wild-type PDGFRB. In conclusion, PDGFRB mutations associated with IBGC impair the receptor signalling. PDGFRB loss of function in IBGC is consistent with recently described inactivating mutations in the PDGF-B ligand. These results raise concerns about the long-term safety of PDGF receptor inhibition by drugs such as imatinib. PMID:25292412

Arts, Florence A; Velghe, Amélie I; Stevens, Monique; Renauld, Jean-Christophe; Essaghir, Ahmed; Demoulin, Jean-Baptiste

2015-01-01

176

Linkage studies in familial idiopathic basal ganglia calcification: separating the wheat from the chaff.  

PubMed

Idiopathic Basal Ganglia Calcification (IBGC) is a neuropsychiatric condition characterized by brain calcinosis, heterogeneous motor impairment and behavioral symptoms. The IBGC1 locus was the first region linked to this phenotype in an American family, but another kindred from Spain was also reported as possibly associated with this locus. Our group excluded this locus in additional families together with an independent study of an Australian pedigree with IBGC, but without clinical symptoms. Recently, a large Italian family from a population isolate was excluded from IBGC1. However, there are unusual aspects concerning this Tyrolean family, especially if we consider that almost all the clinically affected subjects manifested symptoms and signs suggestive of a dysmorphic syndrome, associated with neuropsychiatric symptoms. Curiously, some of the clinical features in this kindred match with the autosomal dominant chromosomal instability syndrome reported in Japan. Previous studies show that the definition of an autosomal dominant pattern of inheritance is an assumption that might be considered cautiously in familial IBGC, due to the limited clinical penetrance for the brain calcifications and especially when there is no access to all the parents neuroimaging data. Families from an Italian isolate, such as Tyrol, with high inbreeding rates, are more likely to manifest recessive syndromes. Nevertheless, the current debate regarding the nosology of this heterogeneous phenotype demands the establishment of standard diagnostic criteria. The current identification of loci or mutations responsible for FIBGC might help to elucidate this intriguing neuropsychiatric condition. PMID:18663732

Oliveira, J R M; Lemos, R R

2009-06-01

177

Identification of a locus on chromosome 14q for idiopathic basal ganglia calcification (Fahr disease).  

PubMed Central

Idiopathic basal ganglia calcification (IBGC) is a neurodegenerative syndrome that is associated with a variety of movement disorders and neurobehavioral and cognitive manifestations. Despite numerous clinical, pathological, and biochemical investigations, its etiology remains unknown. We have identified a multigenerational family with dominantly inherited IBGC and, in 24 members of this family, performed a whole-genome scan using polymorphic microsatellite markers to identify the first chromosomal locus for this disorder (IBGC1). A maximum two-point LOD score of 3.37 was obtained at marker D14S1014, and a maximum multipoint LOD score of 4.95 was obtained between D14S75 and D14S306. The minimal haplotype shared by affected patients extended over a 17.1-cM region bounded by D14S70 and D14S66, which is potentially further narrowed to a 13.3-cM region by a recombination observed in a patient with probable affected status. The age at onset appeared to be decreasing by an average of >20 years with each transmission, which is consistent with genetic anticipation. PMID:10441584

Geschwind, D H; Loginov, M; Stern, J M

1999-01-01

178

Radiation Absorbed Dose to the Basal Ganglia from Dopamine Transporter Radioligand 18F-FPCIT  

PubMed Central

Our previous dosimetry studies have demonstrated that for dopaminergic radiotracers, 18F-FDOPA and 18F-FPCIT, the urinary bladder is the critical organ. As these tracers accumulate in the basal ganglia (BG) with high affinity and long residence times, radiation dose to the BG may become significant, especially in normal control subjects. We have performed dynamic PET measurements using 18F-FPCIT in 16 normal adult subjects to determine if in fact the BG, although not a whole organ, but a well-defined substructure, receives the highest dose. Regions of interest were drawn over left and right BG structures. Resultant time-activity curves were generated and used to determine residence times for dosimetry calculations. S-factors were computed using the MIRDOSE3 nodule model for each caudate and putamen. For 18F-FPCIT, BG dose ranged from 0.029 to 0.069 mGy/MBq. In half of all subjects, BG dose exceeded 85% of the published critical organ (bladder) dose, and in three of those, the BG dose exceeded that for the bladder. The BG can become the dose-limiting organ in studies using dopamine transporter ligands. For some normal subjects studied with F-18 or long half-life radionuclide, the BG may exceed bladder dose and become the critical structure. PMID:25093172

Robeson, William; Dhawan, Vijay; Ma, Yilong; Bjelke, David; Margouleff, Claude; Chaly, Thomas; Eidelberg, David

2014-01-01

179

Indirection and symbol-like processing in the prefrontal cortex and basal ganglia  

PubMed Central

The ability to flexibly, rapidly, and accurately perform novel tasks is a hallmark of human behavior. In our everyday lives we are often faced with arbitrary instructions that we must understand and follow, and we are able to do so with remarkable ease. It has frequently been argued that this ability relies on symbol processing, which depends critically on the ability to represent variables and bind them to arbitrary values. Whereas symbol processing is a fundamental feature of all computer systems, it remains a mystery whether and how this ability is carried out by the brain. Here, we provide an example of how the structure and functioning of the prefrontal cortex/basal ganglia working memory system can support variable binding, through a form of indirection (akin to a pointer in computer science). We show how indirection enables the system to flexibly generalize its behavior substantially beyond its direct experience (i.e., systematicity). We argue that this provides a biologically plausible mechanism that approximates a key component of symbol processing, exhibiting both the flexibility, but also some of the limitations, that are associated with this ability in humans. PMID:24062434

Kriete, Trenton; Noelle, David C.; Cohen, Jonathan D.; O’Reilly, Randall C.

2013-01-01

180

Impaired frontal-basal ganglia connectivity in adolescents with internet addiction.  

PubMed

Understanding the neural basis of poor impulse control in Internet addiction (IA) is important for understanding the neurobiological mechanisms of this syndrome. The current study investigated how neuronal pathways implicated in response inhibition were affected in IA using a Go-Stop paradigm and functional magnetic resonance imaging (fMRI). Twenty-three control subjects aged 15.2±0.5 years (mean±S.D.) and eighteen IA subjects aged 15.1±1.4 years were studied. Effective connectivity within the response inhibition network was quantified using (stochastic) dynamic causal modeling (DCM). The results showed that the indirect frontal-basal ganglia pathway was engaged by response inhibition in healthy subjects. However, we did not detect any equivalent effective connectivity in the IA group. This suggests the IA subjects fail to recruit this pathway and inhibit unwanted actions. This study provides a clear link between Internet addiction as a behavioral disorder and aberrant connectivity in the response inhibition network. PMID:24848380

Li, Baojuan; Friston, Karl J; Liu, Jian; Liu, Yang; Zhang, Guopeng; Cao, Fenglin; Su, Linyan; Yao, Shuqiao; Lu, Hongbing; Hu, Dewen

2014-01-01

181

Idiopathic basal ganglia calcification-associated PDGFRB mutations impair the receptor signalling  

PubMed Central

Platelet-derived growth factors (PDGF) bind to two related receptor tyrosine kinases, which are encoded by the PDGFRA and PDGFRB genes. Recently, heterozygous PDGFRB mutations have been described in patients diagnosed with idiopathic basal ganglia calcification (IBGC or Fahr disease), a rare inherited neurological disorder. The goal of the present study was to determine whether these mutations had a positive or negative impact on the PDGFRB activity. We first showed that the E1071V mutant behaved like wild-type PDGFRB and may represent a polymorphism unrelated to IBGC. In contrast, the L658P mutant had no kinase activity and failed to activate any of the pathways normally stimulated by PDGF. The R987W mutant activated Akt and MAP kinases but did not induce the phosphorylation of signal transducer and activator of transcription 3 (STAT3) after PDGF stimulation. Phosphorylation of phospholipase C? was also decreased. Finally, we showed that the R987W mutant was more rapidly degraded upon PDGF binding compared to wild-type PDGFRB. In conclusion, PDGFRB mutations associated with IBGC impair the receptor signalling. PDGFRB loss of function in IBGC is consistent with recently described inactivating mutations in the PDGF-B ligand. These results raise concerns about the long-term safety of PDGF receptor inhibition by drugs such as imatinib. PMID:25292412

Arts, Florence A; Velghe, Amélie I; Stevens, Monique; Renauld, Jean-Christophe; Essaghir, Ahmed; Demoulin, Jean-Baptiste

2015-01-01

182

The functional connectivity of intralaminar thalamic nuclei in the human basal ganglia.  

PubMed

Projections of the centromedian-parafasicularis neurons of the intralaminar thalamus are major inputs of the striatum. Their functional role in the activity of human basal ganglia (BG) is not well known. The aim of this work was to study the functional connectivity of intralaminar thalamic nuclei with other BG by using the correlations of the BOLD signal recorded during "resting" and a motor task. Intralaminar nuclei showed a marked functional connectivity with all the tested BG, which was observed during "resting" and did not change with the motor task. As regards the intralaminar nuclei, BG connectivity was much lower for the medial dorsal nucleus (a thalamic nucleus bordering the intralaminar nuclei) and for the default mode network (although intralaminar nuclei showed a negative correlation with the default mode network). After the "regression" of intralaminar nuclei activity (partial correlation), the functional connectivity of the caudate and putamen nuclei with other BG decreased (but not with the primary sensorimotor cortex). Present data provide evidence that intralaminar nuclei are not only critical for striatal activity but also for the global performance of human BG, an action involving subcortical BG loops more than cortico-subcortical loops. The high correlation found between BG suggest that, similarly to that reported in other brain centers, the very-slow frequency fluctuations are relevant for the functional activity of these centers. Hum Brain Mapp, 2014. © 2014 Wiley Periodicals, Inc. PMID:25429921

Rodriguez-Sabate, Clara; Llanos, Catalina; Morales, Ingrid; Garcia-Alvarez, Roberto; Sabate, Magdalena; Rodriguez, Manuel

2014-11-27

183

2q37 as a susceptibility locus for idiopathic basal ganglia calcification (IBGC) in a large South Tyrolean family.  

PubMed

Familial idiopathic basal ganglia calcification (FIBGC) is an inherited neurodegenerative disorder characterized by the accumulation of calcium deposits in different brain regions, particularly in the basal ganglia. FIBGC usually follows an autosomal dominant pattern of inheritance. Despite the mapping to chromosome 14q of a susceptibility locus for IBGC (IBCG1) in one family, this locus has been excluded in several others, demonstrating genetic heterogeneity in this disorder. The etiology of this disorder thus remains largely unknown. Using a large extended multigenerational Italian family from South Tyrol with 17 affected in a total of 56 members, we performed a genome-wide linkage analysis in which we were able to exclude linkage to the IBCG1 locus on chromosome 14q and obtain evidence of a novel locus on chromosome 2q37. Electronic supplementary material. The online version of this article (doi:10.1007/s12031-009-9287-3) contains supplementary material, which is available to authorized users. PMID:19757205

Volpato, Claudia Béu; De Grandi, Alessandro; Buffone, Ebba; Facheris, Maurizio; Gebert, Uwe; Schifferle, Günther; Schönhuber, Rudolf; Hicks, Andrew; Pramstaller, Peter P

2009-11-01

184

Interactions between Cortical Rhythms and Spiking Activity of Single Basal Ganglia Neurons in the Normal and Parkinsonian State  

Microsoft Academic Search

In order to evaluate the specific interactions between cortical oscillations and basal ganglia--spiking activity under normal and parkinsonian conditions, we examined the relationship between frontal cortex electroencephalographic (EEG) signals and simulta- neously recorded neuronal activity in the internal and external segmentsofthepallidumorthesubthalamicnucleus(STN)in3rhesus monkeys. After we made recordings in the normal state, hemi- parkinsonism was induced with intracarotid injections of the dopaminergicneurotoxin1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine

Plamen Gatev; Thomas Wichmann

2009-01-01

185

Physiological evidence for a trans-basal ganglia pathway linking extrastriate visual cortex and the superior colliculus  

PubMed Central

Abstract Visually responsive regions along the cat's lateral suprasylvian (LS) sulcus provide excitatory inputs to the deep layers of the superior colliculus (SC). It is via this direct cortico-collicular route that LS cortex is thought to enhance the visual activity of SC output neurons and thereby facilitate SC-mediated orientation behaviours. However, it has long been suggested that LS also might influence the SC via an ‘indirect’ route through the basal ganglia. Such a multi-synaptic route would ultimately modulate SC activity via basal ganglia output neurons in substantia nigra, pars reticulata. Using cortical electrical stimulation, the present experiments in the anaesthetized cat provide a physiological confirmation of this indirect route. Moreover, the patterns of activity evoked in antidromically identified nigro-collicular neurons indicate the involvement of multiple trans-basal ganglia pathways. The most complex evoked patterns consisted of a variable period of inhibition preceded and followed by periods of excitation. Although many neurons displayed only components of this triphasic response, these electrically evoked responses generally matched the characteristics of their responses to natural visual stimuli. Cortical stimulation evoked excitation in all of crossed nigro-collicular neurons and inhibition in the majority of uncrossed nigro-collicular neurons. These data suggest that LS activity accesses multiple trans-basal ganglia circuits that shape nigro-collicular responses that are appropriate for their SC targets. In this way, visual stimuli in one hemifield can be selected as targets for SC-mediated orientation, while simultaneously inhibiting activity in the opposite SC that might generate responses to competing targets. PMID:21986209

Jiang, Huai; Stein, Barry E; McHaffie, John G

2011-01-01

186

Exclusion of linkage to chromosome 14q in a large South Tyrolean family with Idiopathic Basal Ganglia Calcification (IBGC).  

PubMed

Familial Idiopathic Basal Ganglia Calcification (FIBGC) is a neurodegenerative syndrome that usually follows an autosomal dominant pattern of inheritance. Linkage to only one locus on chromosome 14q (IBCG1) has been described so far. We identified and characterized a large multigenerational Italian family from a population isolate with 14 FIBGC affected members. Linkage analysis excluded the IBCG1 locus, thus demonstrating further locus heterogeneity for this disease. PMID:18361429

Volpato, Claudia Béu; De Grandi, Alessandro; Buffone, Ebba; Pichler, Irene; Gebert, Uwe; Schifferle, Günther; Schönhuber, Rudolf; Pramstaller, Peter P

2008-10-01

187

Interactions between Cortical Rhythms and Spiking Activity of Single Basal Ganglia Neurons in the Normal and Parkinsonian State  

PubMed Central

In order to evaluate the specific interactions between cortical oscillations and basal ganglia–spiking activity under normal and parkinsonian conditions, we examined the relationship between frontal cortex electroencephalographic (EEG) signals and simultaneously recorded neuronal activity in the internal and external segments of the pallidum or the subthalamic nucleus (STN) in 3 rhesus monkeys. After we made recordings in the normal state, hemiparkinsonism was induced with intracarotid injections of the dopaminergic neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in one animal, followed by additional recordings. Spiking activity in the pallidum and STN was associated with significant shifts in the level of EEG synchronization. We also found that the spectral power of beta- and gamma-band EEG rhythms covaried positively before the basal ganglia spikes but did not covary or covaried negatively thereafter. In parkinsonism, changes in cortical synchronization and phase coherence were reduced in EEG segments aligned to STN spikes, whereas both were increased in data segments aligned to pallidal spikes. Spiking-related changes in beta/gamma-band covariance were reduced. The findings indicate that basal ganglia and cortex interact in the processing of cortical rhythms that contain oscillations across a broad range of frequencies and that this interaction is severely disrupted in parkinsonism. PMID:18842667

Gatev, Plamen

2009-01-01

188

Interactions between cortical rhythms and spiking activity of single basal ganglia neurons in the normal and parkinsonian state.  

PubMed

In order to evaluate the specific interactions between cortical oscillations and basal ganglia-spiking activity under normal and parkinsonian conditions, we examined the relationship between frontal cortex electroencephalographic (EEG) signals and simultaneously recorded neuronal activity in the internal and external segments of the pallidum or the subthalamic nucleus (STN) in 3 rhesus monkeys. After we made recordings in the normal state, hemiparkinsonism was induced with intracarotid injections of the dopaminergic neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in one animal, followed by additional recordings. Spiking activity in the pallidum and STN was associated with significant shifts in the level of EEG synchronization. We also found that the spectral power of beta- and gamma-band EEG rhythms covaried positively before the basal ganglia spikes but did not covary or covaried negatively thereafter. In parkinsonism, changes in cortical synchronization and phase coherence were reduced in EEG segments aligned to STN spikes, whereas both were increased in data segments aligned to pallidal spikes. Spiking-related changes in beta/gamma-band covariance were reduced. The findings indicate that basal ganglia and cortex interact in the processing of cortical rhythms that contain oscillations across a broad range of frequencies and that this interaction is severely disrupted in parkinsonism. PMID:18842667

Gatev, Plamen; Wichmann, Thomas

2009-06-01

189

A movable microelectrode array for chronic basal ganglia single-unit electrocorticogram co-recording in freely behaving rats.  

PubMed

The basal ganglia-cortical circuits are important for information process to brain function. However, chronic recording of single-unit activities in the basal ganglia nucleus has not yet been well established. We present a movable bundled microwire array for chronic subthalamic nucleus (STN) single-unit electrocorticogram co-recording. The electrode assembly contains a screw-advanced microdrive and a microwire array. The array consists of a steel guide tube, five recording wires and one referenced wire which form the shape of a guiding hand, and one screw electrode for cortico-recording. The electrode can acquire stable cortex oscillation-driven STN firing units in rats under different behaving conditions for 8 weeks. We achieved satisfying signal-to-noise ratio, portions of cells retaining viability, and spike waveform similarities across the recording sections. Using this method, we investigated neural correlations of the basal ganglia-cortical circuits in different behaving conditions. This method will become a powerful tool for multi-region recording to study normal statements or movement disorders. PMID:24838541

Zheng, Xiaobin; Zeng, Jia; Chen, Ting; Lin, Yuanxiang; Yu, Lianghong; Li, Ying; Lin, Zhangya; Wu, Xiyue; Chen, Fuyong; Kang, Dezhi; Zhang, Shizhong

2014-09-01

190

[Idiopathic bilateral basal ganglia calcification (Fahr's disease) presenting with psychotic depression and criminal violence: a case report with forensic aspect].  

PubMed

Fahr's disease is a rare neuropsychiatric disease characterized by bilateral intracranial calcification, primarily in the basal ganglia. The more general term, Fahr's syndrome, is used for primary and secondary basal ganglia calcification, regardless of the etiology, but the term Fahr's disease is used to describe primary, idiopathic cases. Fahr's disease may present with neurological symptoms, such as parkinsonism and extrapyramidal symptoms, dysarthria, paresis, convulsion, and syncope. Psychiatric disorders, including behavioral disorders, psychosis, and mood disorders, as well as cognitive disorders can occur. CT is useful for the diagnosis of Fahr's disease. Herein we present a patient diagnosed as Fahr's disease that presented with symptoms of depression, delusions, and auditory hallucinations. The 47-year-old male patient was hospitalized in a forensic psychiatry inpatient clinic due to aggressive behavior and was subsequently diagnosed with major depressive disorder with psychotic features. While hospitalized he was treated with antidepressant and antipsychotic drugs, as well as electroconvulsive therapy, resulting in significant improvement in his symptoms. As bilateral basal ganglia calcification was observed via CT, the patient was diagnosed as Fahr's disease. This case report emphasizes the importance of cranial imaging and detailed laboratory examination when evaluating patients with psychosis and affective symptoms. Pathologies such as Fahr's disease must be included in the differential diagnosis, especially in cases with neurological symptoms and cranial imaging findings. PMID:24936761

Özer, Ürün; Görgülü, Yasemin; Can Güngör, Ferda; Gençtürk, Mert

2014-01-01

191

Neuronal activity (c-Fos) delineating interactions of the cerebral cortex and basal ganglia  

PubMed Central

The cerebral cortex and basal ganglia (BG) form a neural circuit that is disrupted in disorders such as Parkinson’s disease. We found that neuronal activity (c-Fos) in the BG followed cortical activity, i.e., high in arousal state and low in sleep state. To determine if cortical activity is necessary for BG activity, we administered atropine to rats to induce a dissociative state resulting in slow-wave electroencephalography but hyperactive motor behaviors. Atropine blocked c-Fos expression in the cortex and BG, despite high c-Fos expression in the sub-cortical arousal neuronal groups and thalamus, indicating that cortical activity is required for BG activation. To identify which glutamate receptors in the BG that mediate cortical inputs, we injected ketamine [N-methyl-d-aspartate (NMDA) receptor antagonist] and 6-cyano-nitroquinoxaline-2, 3-dione (CNQX, a non-NMDA receptor antagonist). Systemic ketamine and CNQX administration revealed that NMDA receptors mediated subthalamic nucleus (STN) input to internal globus pallidus (GPi) and substantia nigra pars reticulata (SNr), while non-NMDA receptor mediated cortical input to the STN. Both types of glutamate receptors were involved in mediating cortical input to the striatum. Dorsal striatal (caudoputamen, CPu) dopamine depletion by 6-hydroxydopamine resulted in reduced activity of the CPu, globus pallidus externa (GPe), and STN but increased activity of the GPi, SNr, and putative layer V neurons in the motor cortex. Our results reveal that the cortical activity is necessary for BG activity and clarifies the pathways and properties of the BG-cortical network and their putative role in the pathophysiology of BG disorders. PMID:24723855

Qiu, Mei-Hong; Chen, Michael C.; Huang, Zhi-Li; Lu, Jun

2014-01-01

192

Motor thalamus integration of cortical, cerebellar and basal ganglia information: implications for normal and parkinsonian conditions  

PubMed Central

Motor thalamus (Mthal) is implicated in the control of movement because it is strategically located between motor areas of the cerebral cortex and motor-related subcortical structures, such as the cerebellum and basal ganglia (BG). The role of BG and cerebellum in motor control has been extensively studied but how Mthal processes inputs from these two networks is unclear. Specifically, there is considerable debate about the role of BG inputs on Mthal activity. This review summarizes anatomical and physiological knowledge of the Mthal and its afferents and reviews current theories of Mthal function by discussing the impact of cortical, BG and cerebellar inputs on Mthal activity. One view is that Mthal activity in BG and cerebellar-receiving territories is primarily “driven” by glutamatergic inputs from the cortex or cerebellum, respectively, whereas BG inputs are modulatory and do not strongly determine Mthal activity. This theory is steeped in the assumption that the Mthal processes information in the same way as sensory thalamus, through interactions of modulatory inputs with a single driver input. Another view, from BG models, is that BG exert primary control on the BG-receiving Mthal so it effectively relays information from BG to cortex. We propose a new “super-integrator” theory where each Mthal territory processes multiple driver or driver-like inputs (cortex and BG, cortex and cerebellum), which are the result of considerable integrative processing. Thus, BG and cerebellar Mthal territories assimilate motivational and proprioceptive motor information previously integrated in cortico-BG and cortico-cerebellar networks, respectively, to develop sophisticated motor signals that are transmitted in parallel pathways to cortical areas for optimal generation of motor programmes. Finally, we briefly review the pathophysiological changes that occur in the BG in parkinsonism and generate testable hypotheses about how these may affect processing of inputs in the Mthal. PMID:24273509

Bosch-Bouju, Clémentine; Hyland, Brian I.; Parr-Brownlie, Louise C.

2013-01-01

193

Millisecond timescale disinhibition mediates fast information transmission through an avian basal ganglia loop  

PubMed Central

Avian song learning shares striking similarities with human speech acquisition and requires a basal ganglia (BG)-thalamo-cortical circuit. Information processing and transmission speed in the BG is thought to be limited by synaptic architecture of two serial inhibitory connections. Propagation speed may be critical in the avian BG circuit given the temporally precise control of musculature during vocalization. We used electrical stimulation of the cortical inputs to the BG to study, with fine time resolution, the functional connectivity within this network. We found that neurons in thalamic and cortical nuclei that are not directly connected with the stimulated area can respond to the stimulation with extremely short latencies. Through pharmacological manipulations, we trace this property back to the BG, and show that the cortical stimulation triggers fast disinhibition of the thalamic neurons. Surprisingly, feedforward inhibition mediated by striatal inhibitory neurons onto BG output neurons sometimes precedes the monosynaptic excitatory drive from cortical afferents. The fast feedforward inhibition lengthens a single inter-spike interval in BG output neurons by just a few milliseconds. This short delay is sufficient to drive a strong, brief increase in firing probability in the target thalamic neurons, evoking short latency responses. By blocking glutamate receptors in vivo, we show that thalamic responses do not appear to rely on excitatory drive, and we show in a theoretical model that they could be mediated by post-inhibitory rebound properties. Such fast signalling through disinhibition and rebound may be a crucial specialization for learning of rapid and temporally precise motor acts such as vocal communication. PMID:20007467

Leblois, Arthur; Bodor, Ágnes L; Person, Abigail L; Perkel, David J

2010-01-01

194

Basal Ganglia Disorders Associated with Imbalances in the Striatal Striosome and Matrix Compartments  

PubMed Central

The striatum is composed principally of GABAergic, medium spiny striatal projection neurons (MSNs) that can be categorized based on their gene expression, electrophysiological profiles, and input–output circuits. Major subdivisions of MSN populations include (1) those in ventromedial and dorsolateral striatal regions, (2) those giving rise to the direct and indirect pathways, and (3) those that lie in the striosome and matrix compartments. The first two classificatory schemes have enabled advances in understanding of how basal ganglia circuits contribute to disease. However, despite the large number of molecules that are differentially expressed in the striosomes or the extra-striosomal matrix, and the evidence that these compartments have different input–output connections, our understanding of how this compartmentalization contributes to striatal function is still not clear. A broad view is that the matrix contains the direct and indirect pathway MSNs that form parts of sensorimotor and associative circuits, whereas striosomes contain MSNs that receive input from parts of limbic cortex and project directly or indirectly to the dopamine-containing neurons of the substantia nigra, pars compacta. Striosomes are widely distributed within the striatum and are thought to exert global, as well as local, influences on striatal processing by exchanging information with the surrounding matrix, including through interneurons that send processes into both compartments. It has been suggested that striosomes exert and maintain limbic control over behaviors driven by surrounding sensorimotor and associative parts of the striatal matrix. Consistent with this possibility, imbalances between striosome and matrix functions have been reported in relation to neurological disorders, including Huntington’s disease, L-DOPA-induced dyskinesias, dystonia, and drug addiction. Here, we consider how signaling imbalances between the striosomes and matrix might relate to symptomatology in these disorders. PMID:21941467

Crittenden, Jill R.; Graybiel, Ann M.

2011-01-01

195

TESTING BASAL GANGLIA MOTOR FUNCTIONS THROUGH REVERSIBLE INACTIVATIONS IN THE POSTERIOR INTERNAL GLOBUS PALLIDUS  

PubMed Central

To test current hypotheses on the contribution of the basal ganglia (BG) to motor control, we examined the effects of muscimol-induced inactivations in the skeletomotor region of the internal globus pallidus (sGPi) on visually-directed reaching. Injections were made in 2 monkeys trained to perform four out-and-back reaching movements in quick succession toward four randomly-selected target locations. Following sGPi inactivations: (1) Peak velocity and acceleration were decreased in nearly all sessions whereas movement duration lengthened inconsistently. (2) Reaction times were unaffected on average, although minor changes were observed in several individual sessions. (3) Outward reaches showed a substantial hypometria that correlated closely with bradykinesia, but directional accuracy was unaffected. (4) End-point accuracy was preserved for the slow visually-guided return movements. (5) No impairments were found in the rapid chaining of out-and-back movements, in the selection or initiation of four independent reaches in quick succession, or in the quick on-line correction of initially mis-directed reaches. (6) Inactivation-induced reductions in the magnitude of movement-related muscle activity (EMG) correlated with the severity of slowing and hypometria. There was no evidence for inactivation-induced alterations in the relative timing of EMG bursts, excessive co-contraction, or impaired suppression of antagonist EMG. Therefore, disconnecting the BG motor pathway consistently produced bradykinesia and hypometria, but seldom affected movement initiation time, feedback-mediated guidance, the capacity to produce iterative reaches, or the ability to abruptly reverse movement direction. These results are discussed with reference to the idea that the BG motor loop may regulate energetic expenditures during movement (i.e., movement “vigor”). PMID:18077663

Desmurget, M.; Turner, R.S.

2010-01-01

196

Clinico-radiological Characteristics of Spontaneous Basal Ganglia Hemorrhage, According to Regional Classification  

PubMed Central

Objective The clinico-radiologic features of the spontaneous basal ganglia hemorrhage (BGH) may often differ one from another, according to its regional location. Therefore, we attempted to classify the BGH into regional subgroups, and to extrapolate the distinct characteristics of each group of BGH. Materials and Methods A total of 103 BGHs were analyzed by retrospective review of medical records. BGH was classified according to four subgroups; anterior BGH; posterior BGH; lateral BGH; massive BGH. Results The most common BGH was the posterior BGH (56, 54.4%), followed by the lateral BGH (26, 25.2%), the massive BGH (12, 11.7%), and the anterior BGH (9, 8.7%). The shape of hemorrhage tended to be round in anterior, irregular in posterior, and ovoid in lateral BGH. A layered density of hematoma on initial computed tomography showed correlation with hematoma expansion (p = 0.016), which was observed more often in the postero-lateral group of BGH than in the anterior BGH group. Relatively better recovery from the initial insult was observed in the lateral BGH group than in the other regional BGH groups. The proportion of poor outcome (modified Rankin scale 4, 5, 6) was 100% in the massive, 41.1% in the posterior, 34.6% in the lateral, and 0% in the anterior BGH group. Conclusion We observed that BGH can be grouped according to its regional location and each group may have distinct characteristics. Thus, a more sophisticated clinical strategy tailored to each group of BGHs can be implemented. PMID:25340023

Kim, Do Young; Choo, Yeon Soo; Jang, E Wook; Chung, Joonho; Joo, Jin Yang

2014-01-01

197

Volumetric Changes in the Basal Ganglia After Antipsychotic Monotherapy: A Systematic Review  

PubMed Central

Introduction: Exposure to antipsychotic medication has been extensively associated with structural brain changes in the basal ganglia (BG). Traditionally antipsychotics have been divided into first and second generation antipsychotics (FGAs and SGAs) however, the validity of this classification has become increasingly controversial. To address if specific antipsychotics induce differential effects on BG volumes or whether volumetric effects are explained by FGA or SGA classification, we reviewed longitudinal structural magnetic resonance imaging (MRI) studies investigating effects of antipsychotic monotherapy. Material and Methods: We systematically searched PubMed for longitudinal MRI studies of patients with schizophrenia or non-affective psychosis who had undergone a period of antipsychotic monotherapy. We used specific, predefined search terms and extracted studies were hand searched for additional studies. Results: We identified 13 studies published in the period from 1996 to 2011. Overall six compounds (two classified as FGAs and four as SGAs) have been investigated: haloperidol, zuclophentixol, risperidone, olanzapine, clozapine, and quetiapine. The follow-up period ranged from 3-24 months. Unexpectedly, no studies found that specific FGAs induce significant BG volume increases. Conversely, both volumetric increases and decreases in the BG have been associated with SGA monotherapy. Discussion: Induction of striatal volume increases is not a specific feature of FGAs. Except for clozapine treatment in chronic patients, volume reductions are not restricted to specific SGAs. The current review adds brain structural support to the notion that antipsychotics should no longer be classified as either FGAs or SGAs. Future clinical MRI studies should strive to elucidate effects of specific antipsychotic drugs. PMID:23157636

Ebdrup, B.H; Nørbak, H; Borgwardt, S; Glenthøj, B

2013-01-01

198

[Intraoperative liquid embolization of an arteriovenous malformation in the basal ganglia and thalamic region].  

PubMed

Total three patients with arteriovenous malformation (AVM) in basal ganglia or thalamic region were treated by intraoperative liquid embolizations. These procedures were decided because of repeated hemorrhagic episodes. In the case with AVM in the head of the caudate nucleus which was fed by several anterior perforating arteries originated from anterior cerebral artery (A1 portion) and middle cerebral artery (M1 portion), frontotemporal craniotomy was performed. After the microsurgical dissection of these feeders, one of the feeders lenticulostriate artery, was cannulated with a small-caliber polyethylene catheter, 0.6 mm in outer diameter and 0.3 mm in inner diameter. A small amount of isobutyl 2-cyanoacrylate (IBCA) was injected through the catheter. Same procedure was carried out one month later. Postoperative angiograms revealed about 90% loss of AVM. In two cases with AVM which involved almost entire thalamus, subtemporal craniotomy was done. Feeding vessels which originated from posterior communicating artery and posterior cerebral artery (PCA) were carefully dissected under the operative microscope and one of them was prepared for cannulation with small catheter. When the small amount of IBCA was injected, proximal PCA and internal carotid artery were temporarily occluded. In both cases intraoperative embolization was carried out twice. Postoperative angiograms revealed that the size of AVM was decreased to 20% in one and 40% in the other. Although temporary postoperative deterioration of neurological deficits such as hemiparesis and visual disturbance was slightly noted in all cases, no hemorrhagic episode was experienced for 6 months, 1.5 and 2 years in each after embolization. PMID:3670541

Yamagata, S; Kikuchi, H; Ihara, I; Nagata, I; Naruo, Y; Shishido, H; Itoh, M; Hashimoto, K; Minamikawa, J; Miyamoto, S

1987-07-01

199

Ultra-high field magnetic resonance imaging of the basal ganglia and related structures  

PubMed Central

Deep brain stimulation is a treatment for Parkinson's disease and other related disorders, involving the surgical placement of electrodes in the deeply situated basal ganglia or thalamic structures. Good clinical outcome requires accurate targeting. However, due to limited visibility of the target structures on routine clinical MR images, direct targeting of structures can be challenging. Non-clinical MR scanners with ultra-high magnetic field (7T or higher) have the potential to improve the quality of these images. This technology report provides an overview of the current possibilities of visualizing deep brain stimulation targets and their related structures with the aid of ultra-high field MRI. Reviewed studies showed improved resolution, contrast- and signal-to-noise ratios at ultra-high field. Sequences sensitive to magnetic susceptibility such as T2* and susceptibility weighted imaging and their maps in general showed the best visualization of target structures, including a separation between the subthalamic nucleus and the substantia nigra, the lamina pallidi medialis and lamina pallidi incompleta within the globus pallidus and substructures of the thalamus, including the ventral intermediate nucleus (Vim). This shows that the visibility, identification, and even subdivision of the small deep brain stimulation targets benefit from increased field strength. Although ultra-high field MR imaging is associated with increased risk of geometrical distortions, it has been shown that these distortions can be avoided or corrected to the extent where the effects are limited. The availability of ultra-high field MR scanners for humans seems to provide opportunities for a more accurate targeting for deep brain stimulation in patients with Parkinson's disease and related disorders. PMID:25414656

Plantinga, Birgit R.; Temel, Yasin; Roebroeck, Alard; Uluda?, Kâmil; Ivanov, Dimo; Kuijf, Mark L.; ter Haar Romenij, Bart M.

2014-01-01

200

Function of basal ganglia in bridging cognitive and motor modules to perform an action  

PubMed Central

The basal ganglia (BG) are thought to be involved in the integration of multiple sources of information, and their dysfunction can lead to disorders such as Parkinson's disease (PD). PD patients show motor and cognitive dysfunction with specific impairments in the internal generation of motor actions and executive deficits, respectively. The role of the BG, then, would be to integrate information from several sources in order to make a decision on a resulting action adequate for the required task. Reanalyzing the data set from our previous study (Martinu et al., 2012), we investigated this hypothesis by applying a graph theory method to a series of fMRI data during the performance of self-initiated (SI) finger movement tasks obtained in healthy volunteers (HV) and early stage PD patients. Dorsally, connectivity strength between the medial prefrontal areas (mPFC) and cortical regions including the primary motor area (M1), the extrastriate visual cortex, and the associative cortex, was reduced in the PD patients. The connectivity strengths were positively correlated to activity in the striatum in both groups. Ventrally, all connectivity between the striatum, the thalamus, and the extrastriate visual cortex decreased in strength in the PD, as did the connectivity between the striatum and the ventrolateral PFC (VLPFC). Individual response time (RT) was negatively correlated to connectivity strength between the dorsolateral PFC (DLPFC) and the striatum and positively correlated to connectivity between the VLPFC and the striatum in the HV. These results indicate that the BG, with the mPFC and thalamus, are involved in integrating multiple sources of information from areas such as DLPFC, and VLPFC, connecting to M1, thereby determining a network that leads to the adequate decision and performance of the resulting action. PMID:25071432

Nagano-Saito, Atsuko; Martinu, Kristina; Monchi, Oury

2014-01-01

201

Integration of cortical and pallidal inputs in the basal ganglia-recipient thalamus of singing birds  

PubMed Central

The basal ganglia-recipient thalamus receives inhibitory inputs from the pallidum and excitatory inputs from cortex, but it is unclear how these inputs interact during behavior. We recorded simultaneously from thalamic neurons and their putative synaptically connected pallidal inputs in singing zebra finches. We find, first, that each pallidal spike produces an extremely brief (?5 ms) pulse of inhibition that completely suppresses thalamic spiking. As a result, thalamic spikes are entrained to pallidal spikes with submillisecond precision. Second, we find that the number of thalamic spikes that discharge within a single pallidal interspike interval (ISI) depends linearly on the duration of that interval but does not depend on pallidal activity prior to the interval. In a detailed biophysical model, our results were not easily explained by the postinhibitory “rebound” mechanism previously observed in anesthetized birds and in brain slices, nor could most of our data be characterized as “gating” of excitatory transmission by inhibitory pallidal input. Instead, we propose a novel “entrainment” mechanism of pallidothalamic transmission that highlights the importance of an excitatory conductance that drives spiking, interacting with brief pulses of pallidal inhibition. Building on our recent finding that cortical inputs can drive syllable-locked rate modulations in thalamic neurons during singing, we report here that excitatory inputs affect thalamic spiking in two ways: by shortening the latency of a thalamic spike after a pallidal spike and by increasing thalamic firing rates within individual pallidal ISIs. We present a unifying biophysical model that can reproduce all known modes of pallidothalamic transmission—rebound, gating, and entrainment—depending on the amount of excitation the thalamic neuron receives. PMID:22673333

Goldberg, Jesse H.; Farries, Michael A.

2012-01-01

202

REINFORCEMENT DRIVEN DIMENSIONALITY REDUCTION -A MODEL FOR INFORMATION PROCESSING IN THE BASAL GANGLIA  

E-print Network

GANGLIA Izhar Bar-Gad 1 Eytan Ruppin 2 and Hagai Bergman 1,3 1 Center for Neural Computation, Hebrew. Correspondence To: Izhar Bar-Gad Department of Physiology The Hebrew University ­ Hadassah Medical School P

Ruppin, Eytan

203

[Gait disturbances related to dysfunction of the cerebral cortex and basal ganglia].  

PubMed

This review aimed to characterize the gait disturbances in Parkinson disease (PD) and highlight how a rehabilitation program would affect the care of patients with PD. The typical PD gait is a type of hypokinetic gait characterized by reduced stride length and velocity; shortening of the swing phase; and increase in the stance phase, double-limb support duration, and cadence rate. In the advanced phase of PD, start hesitation, shuffling and festinating gait, propulsion, and freezing of gait (FOG) become remarkable. Notably, in PD, attention may influence gait control, and sensory cueing may improve the stride length. Our study on gait impairment in PD by using a three-dimensional motion analysis system revealed that the stride length and walking speed decreased, but there was no change in cadence. The decreased stride length was due to reduction in the range of movement at the leg and pelvic joints. A 4-week physical rehabilitation program for PD improved the stride length and walking speed;this was achieved by increasing the range of movement of at the leg and pelvic joints. We also assessed the effects of a rehabilitation program for patients with PD who experienced FOG. Although the lower limb function was more impaired in patients with PD and FOG than in those with PD without FOG, the rehabilitation program was effective even for patients with PD and FOG. FOG might be associated with functional impairment of the lower limb as well as dysfunction of the fronto-basal ganglia circuit. We also reported 3 cases of camptocormia (bent spine syndrome) with autonomic dysfunction and rapid eye movement (REM) sleep behavior disorders (RBD) and compared their symptoms with those reported elsewhere. We think that the pedunculopontine nuclear area may control the postural muscle tone and locomotion in PD. On the basis of the results of our rehabilitation programs, we speculate that physical modalities may modify synaptic plasticity by utilizing the cerebellar and/or afferent sensory system. These alternative systems are believed to be functionally intact in patients with PD. PMID:21068456

Takezawa, Nobuo; Mizuno, Toshiki; Seo, Kazuya; Kondo, Masaki; Nakagawa, Masanori

2010-11-01

204

Characterization of multifocal T2*-weighted MRI hypointensities in the basal ganglia of elderly, community-dwelling subjects.  

PubMed

Multifocal T2*-weighted (T2*w) hypointensities in the basal ganglia, which are believed to arise predominantly from mineralized small vessels and perivascular spaces, have been proposed as a biomarker for cerebral small vessel disease. This study provides baseline data on their appearance on conventional structural MRI for improving and automating current manual segmentation methods. Using a published thresholding method, multifocal T2*w hypointensities were manually segmented from whole brain T2*w volumes acquired from 98 community-dwelling subjects in their early 70s. Connected component analysis was used to derive the average T2*w hypointensity count and load per basal ganglia nucleus, as well as the morphology of their connected components, while nonlinear spatial probability mapping yielded their spatial distribution. T1-weighted (T1w), T2-weighted (T2w) and T2*w intensity distributions of basal ganglia T2*w hypointensities and their appearance on T1w and T2w MRI were investigated to gain further insights into the underlying tissue composition. In 75/98 subjects, on average, 3 T2*w hypointensities with a median total volume per intracranial volume of 50.3ppm were located in and around the globus pallidus. Individual hypointensities appeared smooth and spherical with a median volume of 12mm(3) and median in-plane area of 4mm(2). Spatial probability maps suggested an association between T2*w hypointensities and the point of entry of lenticulostriate arterioles into the brain parenchyma. T1w and T2w and especially the T2*w intensity distributions of these hypointensities, which were negatively skewed, were generally not normally distributed indicating an underlying inhomogeneous tissue structure. Globus pallidus T2*w hypointensities tended to appear hypo- and isointense on T1w and T2w MRI, whereas those from other structures appeared iso- and hypointense. This pattern could be explained by an increased mineralization of the globus pallidus. In conclusion, the characteristic spatial distribution and appearance of multifocal basal ganglia T2*w hypointensities in our elderly cohort on structural MRI appear to support the suggested association with mineralized proximal lenticulostriate arterioles and perivascular spaces. PMID:23769704

Glatz, Andreas; Valdés Hernández, Maria C; Kiker, Alexander J; Bastin, Mark E; Deary, Ian J; Wardlaw, Joanna M

2013-11-15

205

Choline-containing compounds detected by proton magnetic resonance spectroscopy in the basal ganglia in bipolar disorder.  

PubMed Central

Choline-containing compounds (Cho) were examined by proton magnetic resonance spectroscopy (1H-MRS) in the left subcortical region, including basal ganglia, in 19 euthymic patients with bipolar disorder and 19 age-matched normal controls. Ten of the patients were treated with lithium; the remaining 9 were not treated with lithium for at least 30 d. The Cho to creatine + phosphocreatine (Cr) peak ratio in the bipolar patients (0.75 +/- 0.38 [mean +/- SD]) was higher than that in the normal controls (0.52 +/- 0.26, P < 0.05). There was no significant difference in the Cho:Cr peak ratio between patients treated with lithium (0.63 +/- 0.36) and without lithium (0.89 +/- 0.35). These results do not support the hypothesis that lithium increases the brain choline-containing compounds, but rather imply that membrane breakdown may occur in the basal ganglia of patients with bipolar disorder. Images Figure 1 PMID:8754593

Kato, T; Hamakawa, H; Shioiri, T; Murashita, J; Takahashi, Y; Takahashi, S; Inubushi, T

1996-01-01

206

Functional details of the basal ganglia as related to the spatial organization of their fibers in cortex and thalamus.  

PubMed

This study compared the results of experimental-morphological and physiological studies in which facts were obtained regarding the functional and morphological heterogeneity of the basal ganglia. Experiments were done on dogs in order to study delayed responses and Hunterian delayed choice responses. Electrical and chemical stimulation of striopallidal structures and recording of spike activity in neurons were done in cats during the formation of conditioned reflexes. Morphological studies were done on cats and dogs by the technique of axon-terminal degeneration. On the basis of an analysis of our own data and data in the literature we have advanced the hypothesis that: 1)There is a correlation between the general features of the disturbance in higher nervous activity and the overlap of striopallidal projections onto cortical and thalamic structures; 2) in a series of cases the behavioral disturbance after shut-off or stimulation of the thalamic structures; 2) in a series of cases the behavioral disturbance after shut-off or stimulation of the basal ganglia can be correlated with the topical details of their projection onto cortical fields and thalamic nuclei. PMID:7343869

Suvorov, N F; Gorbachevskaya, A I; Ermolenko, S F

1981-01-01

207

The effects of age on resting state functional connectivity of the basal ganglia from young to middle adulthood.  

PubMed

The basal ganglia nuclei are critical for a variety of cognitive and motor functions. Much work has shown age-related structural changes of the basal ganglia. Yet less is known about how the functional interactions of these regions with the cerebral cortex and the cerebellum change throughout the lifespan. Here, we took advantage of a convenient sample and examined resting state functional magnetic resonance imaging data from 250 adults 18 to 49years of age, focusing specifically on the caudate nucleus, pallidum, putamen, and ventral tegmental area/substantia nigra (VTA/SN). There are a few main findings to report. First, with age, caudate head connectivity increased with a large region of ventromedial prefrontal/medial orbitofrontal cortex. Second, across all subjects, pallidum and putamen showed negative connectivity with default mode network (DMN) regions such as the ventromedial prefrontal cortex and posterior cingulate cortex, in support of anti-correlation of the "task-positive" network (TPN) and DMN. This negative connectivity was reduced with age. Furthermore, pallidum, posterior putamen and VTA/SN connectivity to other TPN regions, such as somatomotor cortex, decreased with age. These results highlight a distinct effect of age on cerebral functional connectivity of the dorsal striatum and VTA/SN from young to middle adulthood and may help research investigating the etiologies or monitoring outcomes of neuropsychiatric conditions that implicate dopaminergic dysfunction. PMID:25514518

Manza, Peter; Zhang, Sheng; Hu, Sien; Chao, Herta H; Leung, Hoi-Chung; Li, Chiang-Shan R

2015-02-15

208

Blood-nerve barrier: distribution of anionic sites on the endothelial plasma membrane and basal lamina of dorsal root ganglia.  

PubMed

Previous investigations of the blood-nerve barrier have correlated the greater permeability of ganglionic endoneurial vessels, compared to those of nerve trunks, with the presence of fenestrations and open intercellular junctions. Recent studies have demonstrated reduced endothelial cell surface charge in blood vessels showing greater permeability. To determine the distribution of anionic sites on the plasma membranes and basal laminae of endothelial cells in dorsal root ganglia, cationic colloidal gold and cationic ferritin were used. Electron microscopy revealed the existence of endothelial microdomains with differing labelling densities. Labelling indicated that caveolar and fenestral diaphragms and basal laminae are highly anionic at physiological pH, luminal plasma membranes and endothelial processes are moderately charged and abluminal plasma membranes are weakly anionic. Tracers did not occur in caveolae or cytoplasmic vesicles. In vitro tracer experiments at pH values of 7.3, 5.0, 3.5 and 2.0 indicated that the anionic charge on the various endothelial domains was contributed by chemical groups with differing pKa values. In summary, the labelling of ganglionic and sciatic nerve vessels was similar except for the heavy labelling of diaphragms in a minority of endoneurial vessels in ganglia. This difference is likely to account in part for the greater permeability of ganglionic endoneurial vessels. The results are discussed with regard to the blood-nerve and -brain barriers and vascular permeability in other tissues and a comparison made between the ultrastructure and anionic microdomains of epi-, peri- and endoneurial vessels of dorsal root ganglia and sciatic nerves. PMID:1960538

Bush, M S; Reid, A R; Allt, G

1991-09-01

209

Brain MR imaging in patients with hepatic cirrhosis: relationship between high intensity signal in basal ganglia on T1-weighted images and elemental concentrations in brain.  

PubMed

In patients with hepatic cirrhosis, the globus pallidus and putamen show high intensity on T1-weighted MRI. While the causes of this high signal have been thought to include paramagnetic substances, especially manganese, no evidence for this has been presented. Autopsy in four cases of hepatic cirrhosis permitted measurement of metal concentrations in brain and histopathological examination. In three cases the globus pallidus showed high intensity on T1-weighted images. Mean manganese concentrations in globus pallidus, putamen and frontal white matter were 3.03 +/- 0.38, 2.12 +/- 0.37, and 1.38 +/- 0.24 (micrograms/g wet weight), respectively, being approximately four- to almost ten-fold the normal values. Copper concentrations in globus pallidus and putamen were also high, 50% more than normal. Calcium, iron, zinc and magnesium concentrations were all normal. The fourth case showed no abnormal intensity in the basal ganglia and brain metal concentrations were all normal. Histopathologically, cases with showing high signal remarkable atrophy, necrosis, and deciduation of nerve cells and proliferation of glial cells and microglia in globus pallidus.. These findings were similar to those in chronic manganese poisoning. On T1-weighted images, copper deposition shows no abnormal intensity. It is therefore inferred that deposition of highly concentrations of manganese may caused high signal on T1-weighted images and nerve cell death in the globus pallidus. PMID:9272489

Maeda, H; Sato, M; Yoshikawa, A; Kimura, M; Sonomura, T; Terada, M; Kishi, K

1997-08-01

210

Loss of function of Slc20a2 associated with familial idiopathic Basal Ganglia calcification in humans causes brain calcifications in mice.  

PubMed

Familial idiopathic basal ganglia calcification (FIBGC) is a neurodegenerative disorder with neuropsychiatric and motor symptoms. Deleterious mutations in SLC20A2, encoding the type III sodium-dependent phosphate transporter 2 (PiT2), were recently linked to FIBGC in almost 50% of the families reported worldwide. Here, we show that knockout of Slc20a2 in mice causes calcifications in the thalamus, basal ganglia, and cortex, demonstrating that reduced PiT2 expression alone can cause brain calcifications. PMID:23934451

Jensen, Nina; Schrøder, Henrik Daa; Hejbøl, Eva Kildall; Füchtbauer, Ernst-Martin; de Oliveira, João Ricardo Mendes; Pedersen, Lene

2013-11-01

211

Sensory stimulus-sensitive drop attacks and basal ganglia calcification: new findings in a patient with FOLR1 deficiency.  

PubMed

Loss-of-function mutations in the FOLR1 gene (MIM *136430), encoding the folate receptor alpha, impair cerebral folate transport and lead to a progressive neurometabolic disorder. We report on a 5-year-old boy with progressive ataxia, from the age of 2 years and 6 months, with myoclonic jerks, regression, and impressive myoclonic tonic spasms with drop attacks, which were partially provoked by touching his face or washing his hands. Delayed myelination and cerebellar atrophy on cranial MRI were important clues to the diagnosis of cerebral folate transport deficiency, which was confirmed by homozygosity for the known nonsense mutation p.R204X in the FOLR1 gene. Computed tomography taken after head injury revealed bilateral calcifications in the basal ganglia as a novel finding in a patient with FOLR1 mutation. PMID:24556562

Toelle, Sandra P; Wille, David; Schmitt, Bernhard; Scheer, Ianina; Thöny, Beat; Plecko, Barbara

2014-03-01

212

Familial idiopathic basal ganglia calcification (Fahr's disease) without neurological, cognitive and psychiatric symptoms is not linked to the IBGC1 locus on chromosome 14q.  

PubMed

Idiopathic basal ganglia calcification (IBGC) is characterised by radiological, neurological, cognitive and psychiatric abnormalities. The associations between these abnormal phenotypes and abnormal genes remain unclear despite the recent mapping to chromosome 14q of a susceptibility locus for IBGC ( IBGC1). We identified two siblings, from a large multigenerational pedigree, who had both been diagnosed with radiological IBGC, dementia, bipolar affective disorder and Parkinsonism. We assessed (1) other family members to determine whether these four phenotypes were co-segregating as symptoms of IBGC, and (2) possible IBGC linkage to the IBGC1 locus on chromosome 14q or to any known or potential dementia genes. Nine second-generation and 21 third-generation members received radiological, neurological, neuropsychological and psychiatric assessments. We genotyped all family members for microsatellite markers at the IBGC1 locus and polymorphisms of the ApoE, VLDL, alpha1-ACT, BChE-K, APP, PS1, PS2 and tau genes and tested these for linkage to IBGC, dementia and bipolar disorder. Of the ten family members with radiological intracranial calcification, all except the two index cases were normal. There was no significant association between IBGC status and severe cognitive impairment or dementia ( P=0.335) or bipolar affective disorder or Parkinsonism ( P=1.0). Linkage to the IBGC1 locus was excluded. Of the eight dementia gene markers tested, the only positive LOD score was for the ApoE epsilon4 polymorphism and dementia/severe cognitive impairment. We have identified a form of IBGC in which calcification is inherited independently of neurological, cognitive and psychiatric symptoms. This may represent a second locus for this disorder. PMID:11810290

Brodaty, Henry; Mitchell, Philip; Luscombe, Georgina; Kwok, John J; Badenhop, Renee F; McKenzie, Rod; Schofield, Peter R

2002-01-01

213

Multiple Sclerosis and the Accumulation of Iron in the Basal Ganglia: Quantitative Assessment of Brain Iron Using MRI T2 Relaxometry  

Microsoft Academic Search

The aim of this work was to quantify the accumulation of iron in the basal ganglia in multiple sclerosis (MS) patients and in a control group, and to investigate the relationship between iron accumulation and other parameters assessed in MS, i.e. lesion load (LL) and brain parenchymal fraction (BPF). Magnetic resonance imaging T2 relaxometry was used for the measurement. 970

A. Burgetova; Z. Seidl; J. Krasensky; D. Horakova; M. Vaneckova

2010-01-01

214

Basal Ganglia Play a Unique Role in Task Switching within the Frontal-Subcortical Circuits: Evidence from Patients with Focal Lesions  

Microsoft Academic Search

The performance of patients with lesions involving the basal ganglia (BG) was compared to that of patients with prefrontal (PFC) lesions, thalamic (TH) lesions, and age-matched controls in order to examine the specific role of the BG within the frontal-subcortical circuits (FSCC) in task switching. All the BG patients and none of the other participants showed a marked increase in

Einat Yehene; Nachshon Meiran; Nachum Soroker

2008-01-01

215

Adenosine A2A receptor in the monkey basal ganglia: ultrastructural localization and co-localization with the metabotropic glutamate receptor 5 in the striatum  

E-print Network

for the treatment of Parkinson's Disease and other neurological disorders. In rodents, the therapeutic efficacy of A localization in the monkey basal ganglia Associate Editor: Paul Sawchenko Keywords: mGluR5, Parkinson's Disease-727-7519, fax: 404-727-3278, ysmit01@emory.edu Funding sources: Supported by a grant from the National Parkinson

Hall, Randy A

216

The Role of the Basal Ganglia and Its Cortical Connections in Sequence Learning: Evidence from Implicit and Explicit Sequence Learning in Parkinson's Disease  

ERIC Educational Resources Information Center

Implicit (unconscious/incidental) and explicit (conscious/intentional) learning are considered to have distinct neural substrates. It is proposed that implicit learning is mediated by the basal ganglia (BG), while explicit learning has been linked to the medial temporal lobes (MTL). To test such a dissociation we investigated implicit and explicit…

Wilkinson, Leonora; Khan, Zunera; Jahanshahi, Marjan

2009-01-01

217

C. Haegelen Automated segmentation of basal ganglia and deep brain structures in MRI  

E-print Network

tremor or to Tourette syndrome. When pharmaceutical treatments lose effectiveness, such disorders may that is a syndrome of sustained muscle contractions producing writhing movements and abnormal postures, to essential

Paris-Sud XI, Université de

218

[Mineralization of the basal ganglia as the supposed cause of poor tolerance of zuclopenthixol in a patient with long-term untreated paranoid schizophrenia].  

PubMed

Formations described as intracranial calcifications can appear in the course of diseases of the central nervous system, other systems and organs (e.g. endocrine), but also as a disorder of idiopathic character. They are frequently located in subcortical nuclei and usually constitute an incidental finding. This report presents the case of a patient suffering from paranoid schizophrenia for approximately 40 years, who did not agree to any treatment and was hospitalized against her will because she was the threat to the lives of others. She was treated with zuklopentixol resulting in positive symptoms reduction and considerable improvement in social functioning. Unfortunately neurological symptoms appeared: bradykinesis, rigidity--of the type of the lead pipe, balance, posture and gait abnormalities, disturbances in precise hands movements, double-sided Rossolimo's sign, plantar reflex without the participation of the big toe on the left. Neuroimaging studies have demonstrated changes in the form of lenticular nuclei calcification and reduction of signal intensity in posterior parts of both putamens. Neurological symptoms decreased significantly after switching to atypical neuroleptic (olanzapine), and the patient did not require any additional treatment. Mineralization of the basal ganglia can often be associated with psychiatric disorders and it shouldn't be neglected because it can require modification of pharmacotherapy or additional neurological treatment. PMID:24946467

Wichowicz, Hubert M; Wilkowska, Alina; Banecka-Majkutewicz, Zyta; Kummer, ?ukasz; Konarzewska, Joanna; Raczak, Alicja

2013-01-01

219

IP3R1 deficiency in the cerebellum/brainstem causes basal ganglia-independent dystonia by triggering tonic Purkinje cell firings in mice  

PubMed Central

The type 1 inositol 1,4,5- trisphosphate receptor (IP3R1) is a Ca2+ channel on the endoplasmic reticulum and is a predominant isoform in the brain among the three types of IP3Rs. Mice lacking IP3R1 show seizure-like behavior; however the cellular and neural circuit mechanism by which IP3R1 deletion causes the abnormal movements is unknown. Here, we found that the conditional knockout mice lacking IP3R1 specifically in the cerebellum and brainstem experience dystonia and show that cerebellar Purkinje cell (PC) firing patterns were coupled to specific dystonic movements. Recordings in freely behaving mice revealed epochs of low and high frequency PC complex spikes linked to body extension and rigidity, respectively. Remarkably, dystonic symptoms were independent of the basal ganglia, and could be rescued by inactivation of the cerebellum, inferior olive or in the absence of PCs. These findings implicate IP3R1-dependent PC firing patterns in cerebellum in motor coordination and the expression of dystonia through the olivo-cerebellar pathway. PMID:24109434

Hisatsune, Chihiro; Miyamoto, Hiroyuki; Hirono, Moritoshi; Yamaguchi, Naohide; Sugawara, Takeyuki; Ogawa, Naoko; Ebisui, Etsuko; Ohshima, Toshio; Yamada, Masahisa; Hensch, Takao K.; Hattori, Mitsuharu; Mikoshiba, Katsuhiko

2013-01-01

220

Expression and localisation of CYP2D enzymes in rat basal ganglia  

Microsoft Academic Search

P450 enzymes in the CYP2D subfamily have been suggested to contribute to the susceptibility of individuals in developing Parkinson's disease. We have used specific anti-peptide antisera and peroxidase immunohistochemistry to investigate the expression of CYP2D enzymes in the rat brain and some possible factors that may affect their regulation. In male Wistar rats, CYP2D1 was not detected in the basal

Andrew G Riedl; Paul M Watts; Robert J Edwards; Timothy Schulz-Utermoehl; Alan R Boobis; Peter Jenner; C. David Marsden

1999-01-01

221

Network-level neuroplasticity in cortico-basal ganglia pathways Ann M. Graybiel*  

E-print Network

is part of the habit-forming system of the mammalian brain, and that abnormal activation of striatal of Brain and Cognitive Sciences, McGovern Institute for Brain Research, Massachusetts Institute of Technology, 45 Carleton Street, E25-618, Cambridge, MA 02139, USA Abstract The striatum, the largest input

Graybiel, Ann M.

222

Model-based analysis and control of a network of basal ganglia spiking neurons in the normal and Parkinsonian states  

NASA Astrophysics Data System (ADS)

Controlling the spatiotemporal firing pattern of an intricately connected network of neurons through microstimulation is highly desirable in many applications. We investigated in this paper the feasibility of using a model-based approach to the analysis and control of a basal ganglia (BG) network model of Hodgkin-Huxley (HH) spiking neurons through microstimulation. Detailed analysis of this network model suggests that it can reproduce the experimentally observed characteristics of BG neurons under a normal and a pathological Parkinsonian state. A simplified neuronal firing rate model, identified from the detailed HH network model, is shown to capture the essential network dynamics. Mathematical analysis of the simplified model reveals the presence of a systematic relationship between the network's structure and its dynamic response to spatiotemporally patterned microstimulation. We show that both the network synaptic organization and the local mechanism of microstimulation can impose tight constraints on the possible spatiotemporal firing patterns that can be generated by the microstimulated network, which may hinder the effectiveness of microstimulation to achieve a desired objective under certain conditions. Finally, we demonstrate that the feedback control design aided by the mathematical analysis of the simplified model is indeed effective in driving the BG network in the normal and Parskinsonian states to follow a prescribed spatiotemporal firing pattern. We further show that the rhythmic/oscillatory patterns that characterize a dopamine-depleted BG network can be suppressed as a direct consequence of controlling the spatiotemporal pattern of a subpopulation of the output Globus Pallidus internalis (GPi) neurons in the network. This work may provide plausible explanations for the mechanisms underlying the therapeutic effects of deep brain stimulation (DBS) in Parkinson's disease and pave the way towards a model-based, network level analysis and closed-loop control and optimization of DBS parameters, among many other applications. Based on 'Model-based spatiotemporal analysis and control of a network of spiking basal ganglia neurons' by Liu J, Khalil H K and Oweiss K G 2011 in the Proceedings of the 5th IEEE EMBS Conference on Neural Engineering.

Liu, Jianbo; Khalil, Hassan K.; Oweiss, Karim G.

2011-08-01

223

Validation of decision-making models and analysis of decision variables in the rat basal ganglia.  

PubMed

Reinforcement learning theory plays a key role in understanding the behavioral and neural mechanisms of choice behavior in animals and humans. Especially, intermediate variables of learning models estimated from behavioral data, such as the expectation of reward for each candidate choice (action value), have been used in searches for the neural correlates of computational elements in learning and decision making. The aims of the present study are as follows: (1) to test which computational model best captures the choice learning process in animals and (2) to elucidate how action values are represented in different parts of the corticobasal ganglia circuit. We compared different behavioral learning algorithms to predict the choice sequences generated by rats during a free-choice task and analyzed associated neural activity in the nucleus accumbens (NAc) and ventral pallidum (VP). The major findings of this study were as follows: (1) modified versions of an action-value learning model captured a variety of choice strategies of rats, including win-stay-lose-switch and persevering behavior, and predicted rats' choice sequences better than the best multistep Markov model; and (2) information about action values and future actions was coded in both the NAc and VP, but was less dominant than information about trial types, selected actions, and reward outcome. The results of our model-based analysis suggest that the primary role of the NAc and VP is to monitor information important for updating choice behaviors. Information represented in the NAc and VP might contribute to a choice mechanism that is situated elsewhere. PMID:19657038

Ito, Makoto; Doya, Kenji

2009-08-01

224

"Habit" gambling behaviour caused by ischemic lesions affecting the cognitive territories of the basal ganglia.  

PubMed

We report the case of a patient suffering from sudden apathy and pathological gambling-like behaviour after bilateral ischemic lesions involving the dorsal portion of the head of the caudate nuclei and adjacent anterior limb of the internal capsules. This is the first report of the association of an apathy and abnormal gambling behaviour following a stroke affecting sub-cortical structures. Although the location of the lesions, affecting the dorsal striatum, may explain the emergence of an apathetic state, it is, however, at first sight, not easy to explain the gambling behaviour because the patient was normal in tests evaluating sensitivity to reward, and no radiological abnormality was found in the cortical-sub-cortical system of reward. It is proposed that, for this patient, the mechanism of maladaptive gambling behaviour was the development of a routine behaviour related to the patient's cognitive inertia, a mechanism different from the changes in reward sensitivity observed after damage to the orbital ventral prefrontal-ventral striatum system or in dopamine dysregulation syndrome in Parkinson's disease. PMID:20443019

Cognat, Emmanuel; Lagarde, Julien; Decaix, Caroline; Hainque, Elodie; Azizi, Louisa; Gaura-Schmidt, Veronique; Mesnage, Valerie; Levy, Richard

2010-10-01

225

Exploring the cognitive and motor functions of the basal ganglia: an integrative review of computational cognitive neuroscience models  

PubMed Central

Many computational models of the basal ganglia (BG) have been proposed over the past twenty-five years. While computational neuroscience models have focused on closely matching the neurobiology of the BG, computational cognitive neuroscience (CCN) models have focused on how the BG can be used to implement cognitive and motor functions. This review article focuses on CCN models of the BG and how they use the neuroanatomy of the BG to account for cognitive and motor functions such as categorization, instrumental conditioning, probabilistic learning, working memory, sequence learning, automaticity, reaching, handwriting, and eye saccades. A total of 19 BG models accounting for one or more of these functions are reviewed and compared. The review concludes with a discussion of the limitations of existing CCN models of the BG and prescriptions for future modeling, including the need for computational models of the BG that can simultaneously account for cognitive and motor functions, and the need for a more complete specification of the role of the BG in behavioral functions. PMID:24367325

Helie, Sebastien; Chakravarthy, Srinivasa; Moustafa, Ahmed A.

2013-01-01

226

Oculomotor learning revisited: a model of reinforcement learning in the basal ganglia incorporating an efference copy of motor actions  

PubMed Central

In its simplest formulation, reinforcement learning is based on the idea that if an action taken in a particular context is followed by a favorable outcome, then, in the same context, the tendency to produce that action should be strengthened, or reinforced. While reinforcement learning forms the basis of many current theories of basal ganglia (BG) function, these models do not incorporate distinct computational roles for signals that convey context, and those that convey what action an animal takes. Recent experiments in the songbird suggest that vocal-related BG circuitry receives two functionally distinct excitatory inputs. One input is from a cortical region that carries context information about the current “time” in the motor sequence. The other is an efference copy of motor commands from a separate cortical brain region that generates vocal variability during learning. Based on these findings, I propose here a general model of vertebrate BG function that combines context information with a distinct motor efference copy signal. The signals are integrated by a learning rule in which efference copy inputs gate the potentiation of context inputs (but not efference copy inputs) onto medium spiny neurons in response to a rewarded action. The hypothesis is described in terms of a circuit that implements the learning of visually guided saccades. The model makes testable predictions about the anatomical and functional properties of hypothesized context and efference copy inputs to the striatum from both thalamic and cortical sources. PMID:22754501

Fee, Michale S.

2012-01-01

227

Interaction between the 5-HT system and the basal ganglia: functional implication and therapeutic perspective in Parkinson's disease.  

PubMed

The neurotransmitter serotonin (5-HT) has a multifaceted function in the modulation of information processing through the activation of multiple receptor families, including G-protein-coupled receptor subtypes (5-HT1, 5-HT2, 5-HT4-7) and ligand-gated ion channels (5-HT3). The largest population of serotonergic neurons is located in the midbrain, specifically in the raphe nuclei. Although the medial and dorsal raphe nucleus (DRN) share common projecting areas, in the basal ganglia (BG) nuclei serotonergic innervations come mainly from the DRN. The BG are a highly organized network of subcortical nuclei composed of the striatum (caudate and putamen), subthalamic nucleus (STN), internal and external globus pallidus (or entopeduncular nucleus in rodents, GPi/EP and GPe) and substantia nigra (pars compacta, SNc, and pars reticulata, SNr). The BG are part of the cortico-BG-thalamic circuits, which play a role in many functions like motor control, emotion, and cognition and are critically involved in diseases such as Parkinson's disease (PD). This review provides an overview of serotonergic modulation of the BG at the functional level and a discussion of how this interaction may be relevant to treating PD and the motor complications induced by chronic treatment with L-DOPA. PMID:24672433

Miguelez, Cristina; Morera-Herreras, Teresa; Torrecilla, Maria; Ruiz-Ortega, Jose A; Ugedo, Luisa

2014-01-01

228

Emotional blunting following left basal ganglia stroke: the role of depression and fronto-limbic functional alterations.  

PubMed

Disorders of the basal ganglia (BG) alter perception and experience of emotions. Left hemisphere BG (LBG) stroke is also associated with depression. The interplay between depression and alterations in emotional processing following LBG stroke was examined. Evoked affective responses to emotion-laden pictorial stimuli were compared among LBG stroke and healthy participants and participants with stroke damage in brain regions not including the LBG selected to equate depression severity (measured using the Hamilton Depression Scale) with LBG damage participants. Brain activity {[O(15)]water positron emission tomography, PET} was measured in LBG stroke relative to healthy participants to identify changes in regions associated with emotion processing and depression. LBG stroke subjects reported less intense emotions compared with healthy, but not stroke comparison participants. Depression negatively correlated with emotional experience for positive and negative emotions. In response to positive stimuli, LBG subjects exhibited higher activity in amygdala, anterior cingulate, dorsal prefrontal cortex, and insula compared to healthy volunteers. In response to negative stimuli, LBG subjects demonstrated lower activity in right frontal-polar region and fusiform gyrus. Higher baseline activity in amygdala and ventral and mesial prefrontal cortex and lower activity in left dorsal lateral prefrontal cortex were associated with higher depression scores. LBG stroke led to blunted emotions, and brain activity alterations accounting for reduced affective experience, awareness and depression. Depression and fronto-limbic activity changes may contribute to emotional blunting following LBG stroke. PMID:23176970

Paradiso, Sergio; Ostedgaard, Katharine; Vaidya, Jatin; Ponto, Laura Boles; Robinson, Robert

2013-02-28

229

Emotional blunting following left basal ganglia stroke: The role of depression and fronto-limbic functional alterations  

PubMed Central

Disorders of the basal ganglia (BG) alter perception and experience of emotions. Left hemisphere BG (LBG) stroke is also associated with depression. The interplay between depression and alterations in emotional processing following LBG stroke was examined. Evoked affective responses to emotion-laden pictorial stimuli were compared among LBG stroke and healthy participants and participants with stroke damage in brain regions not including the LBG selected to equate depression severity (measured using the Hamilton Depression Scale) with LBG damage participants. Brain activity {[O15]water PET} was measured in LBG stroke relative to healthy participants to identify changes in regions associated with emotion processing and depression. LBG stroke subjects reported less intense emotions compared with healthy, but not stroke comparison participants. Depression negatively correlated with emotional experience for positive and negative emotions. In response to positive stimuli, LBG subjects exhibited higher activity in amygdala, anterior cingulate, dorsal prefrontal cortex, and insula compared to healthy volunteers. In response to negative stimuli, LBG subjects demonstrated lower activity in right frontal-polar region and fusiform gyrus. Higher baseline activity in amygdala and ventral and mesial prefrontal cortex and lower activity in left dorsal lateral prefrontal cortex were associated with higher depression scores. LBG stroke led to blunted emotions, and brain activity alterations accounting for reduced affective experience, awareness and depression. Depression and fronto-limbic activity changes may contribute to emotional blunting following LBG stroke. PMID:23176970

Paradiso, Sergio; Ostedgaard, Katharine; Vaidya, Jatin; Ponto, Laura Boles; Robinson, Robert

2014-01-01

230

The Allocation of Attention to Learning of Goal-Directed Actions: A Cognitive Neuroscience Framework Focusing on the Basal Ganglia  

PubMed Central

The present paper builds on the idea that attention is largely in service of our actions. A framework and model which captures the allocation of attention for learning of goal-directed actions is proposed and developed. This framework highlights an evolutionary model based on the notion that rudimentary functions of the basal ganglia have become embedded into increasingly higher levels of networks which all contribute to adaptive learning. Supporting the proposed model, background literature is presented alongside key evidence based on experimental studies in the so-called “split-brain” (surgically divided cerebral hemispheres), and selected evidence from related areas of research. Although overlap with other existing findings and models is acknowledged, the proposed framework is an original synthesis of cognitive experimental findings with supporting evidence of a neural system and a carefully formulated model of attention. It is the hope that this new synthesis will be informative in fields of cognition and other fields of brain sciences and will lead to new avenues for experimentation across domains. PMID:23267335

Franz, E. A.

2012-01-01

231

One View of the Current State of Understanding in Basal Ganglia Pathophysiology and What is Needed for the Future  

PubMed Central

Deep Brain Stimulation (DBS), arguably, is the most dramatic development in movement disorders since the levodopa for Parkinson’s disease. Yet, its mechanisms of action of DBS are unknown. However, DBS related research already has demonstrated that current concepts of basal ganglia pathophysiology are wrong. Specifically, the notion that over-activity of the globus pallidus interna causes parkinsonism, the basis for the most current theories, is no longer tenable. The development of any new theory will be aided by an understanding of how current theories are wrong and why have these flawed theories persist. Many of the problems of current theories are more matters of inference, assumptions, presumptions, and the accepted level of ambiguity than they are of fact. Consequently, it is imperative that these issues be addressed. Just as the inappropriate use of a tool or method is grounds for criticism, methods of reasoning are tools that can be used inappropriately and should be subject to discussion just as misuse of any other tool. Thorough criticism can provide very important lesions though the process could be mistaken as harsh or personal; neither is the case here. At the least, such analyzes can point to potential pitfalls that could be avoided in the development of new theories. As will be discussed, theories are important for the development of therapies but perhaps most important, for the acceptance of new therapies, as was the case for the recent resurgence of interest in surgical therapies. PMID:24868387

Montgomery, Erwin B.

2011-01-01

232

The substantia nigra conveys target-dependent excitatory and inhibitory outputs from the basal ganglia to the thalamus.  

PubMed

The basal ganglia (BG), which influence cortical activity via the thalamus, play a major role in motor activity, learning and memory, sensory processing, and many aspects of behavior. The substantia nigra (SN) consists of GABAergic neurons of the pars reticulata that inhibit thalamic neurons and provide the primary output of the BG, and dopaminergic neurons of the pars compacta that modulate thalamic excitability. Little is known about the functional properties of the SN?thalamus synapses, and anatomical characterization has been controversial. Here we use a combination of anatomical, electrophysiological, genetic, and optogenetic approaches to re-examine these synaptic connections in mice. We find that neurons in the SN inhibit neurons in the ventroposterolateral nucleus of the thalamus via GABAergic synapses, excite neurons in the thalamic nucleus reticularis, and both excite and inhibit neurons within the posterior nucleus group. Glutamatergic SN neurons express the vesicular glutamate receptor transporter vGluT2 and receive inhibitory synapses from striatal neurons, and many also express tyrosine hydroxylase, a marker of dopaminergic neurons. Thus, in addition to providing inhibitory outputs, which is consistent with the canonical circuit, the SN provides glutamatergic outputs that differentially target thalamic nuclei. This suggests that an increase in the activity of glutamatergic neurons in the SN allows the BG to directly excite neurons in specific thalamic nuclei. Elucidating an excitatory connection between the BG and the thalamus provides new insights into how the BG regulate thalamic activity, and has important implications for understanding BG function in health and disease. PMID:24899724

Antal, Miklos; Beneduce, Brandon M; Regehr, Wade G

2014-06-01

233

Interaction between the 5-HT system and the basal ganglia: functional implication and therapeutic perspective in Parkinson's disease  

PubMed Central

The neurotransmitter serotonin (5-HT) has a multifaceted function in the modulation of information processing through the activation of multiple receptor families, including G-protein-coupled receptor subtypes (5-HT1, 5-HT2, 5-HT4–7) and ligand-gated ion channels (5-HT3). The largest population of serotonergic neurons is located in the midbrain, specifically in the raphe nuclei. Although the medial and dorsal raphe nucleus (DRN) share common projecting areas, in the basal ganglia (BG) nuclei serotonergic innervations come mainly from the DRN. The BG are a highly organized network of subcortical nuclei composed of the striatum (caudate and putamen), subthalamic nucleus (STN), internal and external globus pallidus (or entopeduncular nucleus in rodents, GPi/EP and GPe) and substantia nigra (pars compacta, SNc, and pars reticulata, SNr). The BG are part of the cortico-BG-thalamic circuits, which play a role in many functions like motor control, emotion, and cognition and are critically involved in diseases such as Parkinson's disease (PD). This review provides an overview of serotonergic modulation of the BG at the functional level and a discussion of how this interaction may be relevant to treating PD and the motor complications induced by chronic treatment with L-DOPA. PMID:24672433

Miguelez, Cristina; Morera-Herreras, Teresa; Torrecilla, Maria; Ruiz-Ortega, Jose A.; Ugedo, Luisa

2014-01-01

234

Mutation Analysis of SLC20A2 and SPP2 as Candidate Genes for Familial Idiopathic Basal Ganglia Calcification  

PubMed Central

Background Familial Idiopathic Basal Ganglia Calcification (IBGC) is a rare neurodegenerative disorder which is usually transmitted as an autosomal dominant trait. IBGC is genetically heterogeneous and SLC20A2, on chromosome 8p21.1–8q11.23, is the first gene found in IBGC-affected patients with varied ancestry. On the other hand, several candidate genes for IBGC on chromosome 2q37, including the SPP2 gene, may play a role in inhibiting calcification. Methods Totally, 22 members of a three generational Iranian family affected by IBGC, with an autosomal dominant pattern of inheritance were included in this study. DNA was extracted from the whole blood using standard salting out method. To find a mutation responsible for IBGC, we sequenced the coding region of SLC20A2 as well as promoter and coding region of SPP2 in the index subject of IBGC-affected family. Results Pathogenic mutation was found neither in SLC20A2 nor in SPP2. Conclusion Our results strengthen genetic heterogeneity of this condition. Additional mutation studies are necessary to find a gene or genes responsible for IBGC in this affected family. PMID:24286000

Ashtari, Fereshteh; Saliminejad, Kioomars; Ahani, Ali; Kamali, Koorosh; Pahlevanzadeh, Zhamak; Khorshid, Hamid Reza Khorram

2013-01-01

235

Neuroradiologic evidence of pre-synaptic and post-synaptic nigrostriatal dopaminergic dysfunction in idiopathic Basal Ganglia calcification: a case report.  

PubMed

Idiopathic basal ganglia calcification (IBGC) is a neuropathological condition known to manifest as motor disturbance, cognitive impairment, and psychiatric symptoms. The pathophysiology of the psychiatric symptoms of IBGC, however, remains controversial. A previous biochemical study suggested that dopaminergic impairment is involved in IBGC. We thus hypothesized that dopaminergic dysfunction might be related with the psychiatric manifestations of IBGC. We used positron emission tomography to measure glucose metabolism and dopaminergic function in the basal ganglia of an IBGC patient with psychiatric symptoms. The results showed that widespread hypometabolism was evident in the frontal, temporal, and parietal cortices while the decline in dopaminergic function was severe in the bilateral striatum. The functional decline of the dopamine system in the calcified area of the bilateral striatum and the disruption of cortico-subcortical circuits may contribute to clinical manifestations of IBGC in our patient. PMID:19021829

Saito, Takahiro; Nakamura, Mitsuru; Shimizu, Teruhiko; Oda, Keiichi; Ishiwata, Kiichi; Ishii, Kenji; Isse, Kunihiro

2010-04-01

236

The Dopamine D1–D2 Receptor Heteromer in Striatal Medium Spiny Neurons: Evidence for a Third Distinct Neuronal Pathway in Basal Ganglia  

PubMed Central

Dopaminergic signaling within the basal ganglia has classically been thought to occur within two distinct neuronal pathways; the direct striatonigral pathway which contains the dopamine D1 receptor and the neuropeptides dynorphin (DYN) and substance P, and the indirect striatopallidal pathway which expresses the dopamine D2 receptor and enkephalin (ENK). A number of studies have also shown, however, that D1 and D2 receptors can co-exist within the same medium spiny neuron and emerging evidence indicates that these D1/D2-coexpressing neurons, which also express DYN and ENK, may comprise a third neuronal pathway, with representation in both the striatonigral and striatopallidal projections of the basal ganglia. Furthermore, within these coexpressing neurons it has been shown that the dopamine D1 and D2 receptor can form a novel and pharmacologically distinct receptor complex, the dopamine D1–D2 receptor heteromer, with unique signaling properties. This is indicative of a functionally unique role for these neurons in brain. The aim of this review is to discuss the evidence in support of a novel third pathway coexpressing the D1 and D2 receptor, to discuss the potential relevance of this pathway to basal ganglia signaling, and to address its potential value, and that of the dopamine D1–D2 receptor heteromer, in the search for new therapeutic strategies for disorders involving dopamine neurotransmission. PMID:21747759

Perreault, Melissa L.; Hasbi, Ahmed; O’Dowd, Brian F.; George, Susan R.

2011-01-01

237

Aberrant basal ganglia metabolism in fragile X syndrome: a magnetic resonance spectroscopy study  

PubMed Central

Background The profile of cognitive and behavioral variation observed in individuals with fragile X syndrome (FXS), the most common known cause of inherited intellectual impairment, suggests aberrant functioning of specific brain systems. Research investigating animal models of FXS, characterized by limited or lack of fragile X mental retardation protein, (FMRP), has linked brain dysfunction to deficits in the cholinergic and glutamatergic systems. Thus, we sought to examine in vivo levels of neurometabolites related to cholinergic and glutamatergic functioning in males and females with FXS. Methods The study participants included 18 adolescents and young adults with FXS, and a comparison group of 18 individuals without FXS matched for age, sex and general intellectual functioning. Proton magnetic resonance spectroscopy (MRS) was used to assess neurometabolite levels in the caudate nucleus, a region known to be greatly enlarged and involved in abnormal brain circuitry in individuals with FXS. A general linear model framework was used to compare group differences in metabolite concentration. Results We observed a decrease in choline (P?=?0.027) and in glutamate?+?glutamine (P?=?0.032) in the caudate nucleus of individuals with FXS, relative to individuals in the comparison group. Conclusions This study provides evidence of metabolite differences in the caudate nucleus, a brain region of potential importance to our understanding of the neural deficits underlying FXS. These metabolic differences may be related to aberrant receptor signaling seen in animal models. Furthermore, identification of the specific neurometabolites involved in FXS dysfunction could provide critical biomarkers for the design and efficacy tracking of disease-specific pharmacological treatments. PMID:23981510

2013-01-01

238

Consequences of Nigrostriatal Denervation on the Functioning of the Basal Ganglia in Human and Nonhuman Primates: An In Situ Hybridization Study of Cytochrome Oxidase Subunit I mRNA  

Microsoft Academic Search

To examine the consequences of nigrostriatal denervation and chronic levodopa (L-DOPA) treatment on functional activity of the basal ganglia, we analyzed, using in situ hybridization, the cellular expression of the mRNA encoding for cytochrome oxidase sub- unit I (COI mRNA), a molecular marker for functional neuronal activity, in the basal ganglia. This analysis was performed in monkeys rendered parkinsonian by

Miquel Vila; Richard Levy; Maria-Trinidad Herrero; Merle Ruberg; Baptiste Faucheux; Yves Agid; Etienne C. Hirsch

1997-01-01

239

Model-Based Analysis and Control of a Network of Basal Ganglia Spiking Neurons in the Normal and Parkinsonian States  

PubMed Central

Controlling the spatiotemporal firing pattern of an intricately connected network of neurons through microstimulation is highly desirable in many applications. We investigated in this paper the feasibility of using a model-based approach to the analysis and control of a Basal Ganglia (BG) network model of Hodgkin–Huxley (HH) spiking neurons through microstimulation. Detailed analysis of this network model suggests that it can reproduce the experimentally observed characteristics of BG neurons under a normal and a pathological Parkinsonian state. A simplified neuronal firing rate model, identified from the detailed HH network model, is shown to capture the essential network dynamics. Mathematical analysis of the simplified model reveals the presence of a systematic relationship between the network’s structure and its dynamic response to spatiotemporally patterned microstimulation. We show that both the network synaptic organization and the local mechanism of microstimulation can impose tight constraints on the possible spatiotemporal firing patterns that can be generated by the microstimulated network, which may hinder the effectiveness of microstimulation to achieve a desired objective under certain conditions. Finally, we demonstrate that the feedback control design aided by the mathematical analysis of the simplified model is indeed effective in driving the BG network in the normal and Parskinsonian states to follow a prescribed spatiotemporal firing pattern. We further show that the rhythmic/oscillatory patterns that characterize a dopamine-depleted BG network can be suppressed as a direct consequence of controlling the spatiotemporal pattern of a subpopulation of the output Globus Pallidus internalis (GPi) neurons in the network. This work may provide plausible explanations for the mechanisms underlying the therapeutic effects of Deep Brain Stimulation (DBS) in PD and pave the way towards a model-based, network level analysis and closed-loop control and optimization of DBS parameters, among many other applications. PMID:21775788

Liu, Jianbo; Khalil, Hassan K.; Oweiss, Karim G.

2011-01-01

240

Emergent structured transition from variation to repetition in a biologically-plausible model of learning in basal ganglia  

PubMed Central

Often, when animals encounter an unexpected sensory event, they transition from executing a variety of movements to repeating the movement(s) that may have caused the event. According to a recent theory of action discovery (Redgrave and Gurney, 2006), repetition allows the animal to represent those movements, and the outcome, as an action for later recruitment. The transition from variation to repetition often follows a non-random, structured, pattern. While the structure of the pattern can be explained by sophisticated cognitive mechanisms, simpler mechanisms based on dopaminergic modulation of basal ganglia (BG) activity are thought to underlie action discovery (Redgrave and Gurney, 2006). In this paper we ask the question: can simple BG-mediated mechanisms account for a structured transition from variation to repetition, or are more sophisticated cognitive mechanisms always necessary? To address this question, we present a computational model of BG-mediated biasing of behavior. In our model, unlike most other models of BG function, the BG biases behavior through modulation of cortical response to excitation; many possible movements are represented by the cortical area; and excitation to the cortical area is topographically-organized. We subject the model to simple reaching tasks, inspired by behavioral studies, in which a location to which to reach must be selected. Locations within a target area elicit a reinforcement signal. A structured transition from variation to repetition emerges from simple BG-mediated biasing of cortical response to excitation. We show how the structured pattern influences behavior in simple and complicated tasks. We also present analyses that describe the structured transition from variation to repetition due to BG-mediated biasing and from biasing that would be expected from a type of cognitive biasing, allowing us to compare behavior resulting from these types of biasing and make connections with future behavioral experiments. PMID:24575067

Shah, Ashvin; Gurney, Kevin N.

2014-01-01

241

Striatal dopamine modulates basal ganglia output and regulates social context-dependent behavioral variability through D1 receptors  

PubMed Central

Cortico–basal ganglia (BG) circuits are thought to promote the acquisition of motor skills through reinforcement learning. In songbirds, a specialized portion of the BG is responsible for song learning and plasticity. This circuit generates song variability that underlies vocal experimentation in young birds and modulates song variability depending on the social context in adult birds. When male birds sing in the presence of a female, a social context associated with decreased BG-induced song variability, the extracellular dopamine (DA) level is increased in the avian BG nucleus Area X. These results suggest that DA could trigger song variability changes through its action in Area X. Consistent with this hypothesis, we report that DA delivered to Area X weakens the output signal of the avian cortico-BG circuit. Acting through D1 receptors, DA reduced responses in Area X to song playback and to electrical stimulation of its afferent cortical nucleus HVC. Specifically, DA reduced the response to direct excitatory input and decreased firing variability in Area X pallidal neurons, which provide the output to the thalamus. As a consequence, DA delivery in Area X also decreased responses to song playback in the cortical output nucleus of the BG loop, the lateral magnocellular nucleus of the anterior nidopallium (LMAN). Further, interfering with D1 receptor transmission in Area X abolished social context-related changes in song variability. In conclusion, we propose that DA acts on D1 receptors in Area X to modulate the BG output signal and trigger changes in song variability. PMID:20410125

Leblois, Arthur; Wendel, Benjamin J.; Perkel, David J

2010-01-01

242

Dynamic Stereotypic Responses of Basal Ganglia Neurons to Subthalamic Nucleus High-Frequency Stimulation in the Parkinsonian Primate  

PubMed Central

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. PMID:21559345

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

2011-01-01

243

Temporal Sequence of Ictal discharges Propagation in the Corticolimbic Basal Ganglia System during Amygdala Kindled Seizures in Freely Moving Rats  

PubMed Central

We used a multiple channel, single unit recording technique to investigate the neural activity in different corticolimbic and basal ganglia regions in freely moving rats before and during generalized amygdala kindled seizures. Neural activity was recorded simultaneously in the sensorimotor cortex (Ctx), hippocampus, amygdala, substantia nigra pars reticulata (SNr) and the subthalamic nucleus (STN). We observed massive synchronized activity among neurons of different brain regions during seizure episodes. Neurons in the kindled amygdala led other regions in synchronized firing, revealed by time lags of neurons in other regions in crosscorrelogram analysis. While there was no obvious time lag between Ctx and SNr, the STN and hippocampus did lag behind the Ctx and SNr in correlated firing. Activity in the amygdala and SNr contralateral to the kindling stimulation site lagged behind their ipsilateral counterparts. However no time lag was found between the kindling and contralateral sides of Ctx, hippocampus and STN. Our data confirm that the amygdala is an epileptic focus that emits ictal discharges to other brain regions. The observed temporal pattern indicates that ictal discharges from the amygdala arrive first at Ctx and SNr, and then spread to the hippocampus and STN. The simultaneous activation of both sides of the Ctx suggests that the neocortex participates in kindled seizures as a unisonant entity to provoke the clonic motor seizures. Early activation of the SNr (before the STN and hippocampus) points to an important role of the SNr in amygdala kindled seizures and supports the view that different SNr manipulations may be effective ways to control seizures. PMID:17049434

Shi, Li-Hong; Luo, Fei; Woodward, Donald J.; McIntyre, Dan C.; Chang, Jing-Yu

2007-01-01

244

Striatal dopamine ramping may indicate flexible reinforcement learning with forgetting in the cortico-basal ganglia circuits  

PubMed Central

It has been suggested that the midbrain dopamine (DA) neurons, receiving inputs from the cortico-basal ganglia (CBG) circuits and the brainstem, compute reward prediction error (RPE), the difference between reward obtained or expected to be obtained and reward that had been expected to be obtained. These reward expectations are suggested to be stored in the CBG synapses and updated according to RPE through synaptic plasticity, which is induced by released DA. These together constitute the “DA=RPE” hypothesis, which describes the mutual interaction between DA and the CBG circuits and serves as the primary working hypothesis in studying reward learning and value-based decision-making. However, recent work has revealed a new type of DA signal that appears not to represent RPE. Specifically, it has been found in a reward-associated maze task that striatal DA concentration primarily shows a gradual increase toward the goal. We explored whether such ramping DA could be explained by extending the “DA=RPE” hypothesis by taking into account biological properties of the CBG circuits. In particular, we examined effects of possible time-dependent decay of DA-dependent plastic changes of synaptic strengths by incorporating decay of learned values into the RPE-based reinforcement learning model and simulating reward learning tasks. We then found that incorporation of such a decay dramatically changes the model's behavior, causing gradual ramping of RPE. Moreover, we further incorporated magnitude-dependence of the rate of decay, which could potentially be in accord with some past observations, and found that near-sigmoidal ramping of RPE, resembling the observed DA ramping, could then occur. Given that synaptic decay can be useful for flexibly reversing and updating the learned reward associations, especially in case the baseline DA is low and encoding of negative RPE by DA is limited, the observed DA ramping would be indicative of the operation of such flexible reward learning. PMID:24782717

Morita, Kenji; Kato, Ayaka

2014-01-01

245

Identification of a novel genetic locus on chromosome 8p21.1-q11.23 for idiopathic basal ganglia calcification.  

PubMed

Idiopathic basal ganglia calcification (IBGC) is a neurodegenerative disorder that is characterized by basal ganglia and extrabasal ganglia calcification, and usually inherited in an autosomal dominant pattern. To date, two genetic loci for IBGC were identified on chromosomes 14q and 2q, but further genetic heterogeneity clearly exists. In this study, a large Chinese family with autosomal dominant IBGC was characterized. Linkage analysis excluded the 14q13 and 2q37 loci. The large family was then characterized by genome-wide linkage analysis to identify a novel genetic locus for IBGC. Significant linkage was identified with markers on chromosome 8p21.1-q11.23 with a maximum LOD score of 4.10. Fine mapping defined the new genetic locus within a 25?Mb region between markers D8S1809 and D8S1833. Future studies of the candidate genes at the 8p21.1-q11.23 locus may lead to identification of a disease-causing gene with IBGC. PMID:20552677

Dai, Xiaohua; Gao, Yong; Xu, Zhenping; Cui, Xiaoniu; Liu, Juan; Li, Yulei; Xu, Haibo; Liu, Mugen; Wang, Qing K; Liu, Jing Yu

2010-10-01

246

Adenosine A2A Receptor in the Monkey Basal Ganglia: Ultrastructural Localization and Colocalization With the Metabotropic Glutamate Receptor 5 in the Striatum  

PubMed Central

The adenosine A2A receptor (A2AR) is a potential drug target for the treatment of Parkinson’s disease and other neurological disorders. In rodents, the therapeutic efficacy of A2AR modulation is improved by concomitant modulation of the metabotropic glutamate receptor 5 (mGluR5). To elucidate the anatomical substrate(s) through which these therapeutic benefits could be mediated, pre-embedding electron microscopy immunohistochemistry was used to conduct a detailed, quantitative ultrastructural analysis of A2AR localization in the primate basal ganglia and to assess the degree of A2AR/mGluR5 colocalization in the striatum. A2AR immunoreactivity was found at the highest levels in the striatum and external globus pallidus (GPe). However, the monkey, but not the rat, substantia nigra pars reticulata (SNr) also harbored a significant level of neuropil A2AR immunoreactivity. At the electron microscopic level, striatal A2AR labeling was most commonly localized in postsynaptic elements (58% ± 3% of labeled elements), whereas, in the GPe and SNr, the labeling was mainly presynaptic (71% ± 5%) or glial (27% ± 6%). In both striatal and pallidal structures, putative inhibitory and excitatory terminals displayed A2AR immunoreactivity. Striatal A2AR/mGluR5 colocalization was commonly found; 60–70% of A2AR-immunoreactive dendrites or spines in the monkey striatum coexpress mGluR5. These findings provide the first detailed account of the ultrastructural localization of A2AR in the primate basal ganglia and demonstrate that A2AR and mGluR5 are located to interact functionally in dendrites and spines of striatal neurons. Together, these data foster a deeper understanding of the substrates through which A2AR could regulate primate basal ganglia function and potentially mediate its therapeutic effects in parkinsonism. PMID:21858817

Bogenpohl, James W.; Ritter, Stefanie L.; Hall, Randy A.; Smith, Yoland

2012-01-01

247

Differentiation of sCJD and vCJD forms by automated analysis of basal ganglia intensity distribution in multisequence MRI of the brain--definition and evaluation of new MRI-based ratios.  

PubMed

We present a method for the analysis of basal ganglia (including the thalamus) for accurate detection of human spongiform encephalopathy in multisequence magnetic resonance imaging (MRI) of the brain. One common feature of most forms of prion protein diseases is the appearance of hyperintensities in the deep grey matter area of the brain in T2-weighted magnetic resonance (MR) images. We employ T1, T2, and Flair-T2 MR sequences for the detection of intensity deviations in the internal nuclei. First, the MR data are registered to a probabilistic atlas and normalized in intensity. Then smoothing is applied with edge enhancement. The segmentation of hyperintensities is performed using a model of the human visual system. For more accurate results, a priori anatomical data from a segmented atlas are employed to refine the registration and remove false positives. The results are robust over the patient data and in accordance with the clinical ground truth. Our method further allows the quantification of intensity distributions in basal ganglia. The caudate nuclei are highlighted as main areas of diagnosis of sporadic Creutzfeldt-Jakob Disease (sCJD), in agreement with the histological data. The algorithm permitted the classification of the intensities of abnormal signals in sCJD patient FLAIR images with a higher hypersignal in caudate nuclei (10/10) and putamen (6/10) than in thalami. Defining normalized MRI measures of the intensity relations between the internal grey nuclei of patients, we robustly differentiate sCJD and variant CJD (vCJD) patients, in an attempt to create an automatic classification tool of human spongiform encephalopathies. PMID:16894998

Linguraru, Marius George; Ayache, Nicholas; Bardinet, Eric; Ballester, Miguel Angel González; Galanaud, Damien; Haïk, Stéphane; Faucheux, Baptiste; Hauw, Jean-Jacques; Cozzone, Patrick; Dormont, Didier; Brandel, Jean-Philippe

2006-08-01

248

Analysis of the CTAGE5 P521A variation with the risk of familial idiopathic basal ganglia calcification in an Iranian population.  

PubMed

Familial idiopathic basal ganglia calcification (IBGC) is a rare neurodegenerative syndrome with an autosomal dominant pattern of inheritance which is characterized by deposition of calcium in the basal ganglia and other brain regions. Linkage studies demonstrated its genetic heterogeneity; however, the responsible genes are unknown. Recently, a heterozygous variation (C>G, P521A) at exon 20 of the human cutaneous T cell lymphoma-associated antigen 5 (CTAGE5) gene was found in all patients of the affected large American family linked to IBGC1 (14q11.2-21.3). However, no carrier was detected in the two affected Brazilian families. This study was performed to investigate whether the CTAGE5 P521A variation is associated with the IBGC in an affected Iranian family. Genotyping of the CTAGE5 P521A variation was determined using PCR-RFLP. Totally, 22 members of an affected Iranian family as well as 100 normal people as control group were screened. All the samples including 22 members of the affected family as well as all control people had normal CC genotype and no GC carrier was found. Our result is similar to a Brazilian study but contrary to an American report, strengthening genetic heterogeneity of this syndrome. It seems that additional studies are necessary to confirm the pathogenicity of this rare mutation. PMID:23054591

Saliminejad, Kioomars; Ashtari, Fereshteh; Kamali, Koroosh; Edalatkhah, Haleh; Khorram Khorshid, Hamid Reza

2013-03-01

249

An evaluation of distinct volumetric and functional MRI contributions toward understanding age and task performance: A study in the basal ganglia  

PubMed Central

Prior work by our group and others has implicated the basal ganglia as important in age-related differences in tasks involving motor response control. The present study used structural and functional MRI approaches to analyze this region of interest (ROI) toward better understanding the contributions of structural and functional MRI measures to understanding age-related and task performance-related cognitive differences. Eleven healthy elders were compared with 11 healthy younger adults while they completed the “go” portion of a complex Go/No-go task. Separate ROI’s in the bilateral caudate (C) and putamen/globus pallidus (PGp) were studied based upon previous findings of age-related functional MRI differences in basal ganglia for this portion of the task. Structural volumes and functional activation (in percent area under the curve during correct responses) were independently extracted for these ROI’s. Results showed that age correlated with ROI volume in bilateral PGp and C, while multiple task performance measures correlated with functional activation in the left PGp. The Go/No-go task measures were also significantly correlated with traditional attention and executive functioning measures. Importantly, fMRI activation and volumes from each ROI were not significantly inter-correlated. These findings suggest that structural and functional MRI make unique contributions to the study of performance changes in aging. PMID:17210145

Langenecker, Scott A.; Briceno, Emily M.; Hamid, Najat M.; Nielson, Kristy A.

2007-01-01

250

Phase Relationships Support a Role for Coordinated Activity in the Indirect Pathway in Organizing Slow Oscillations in Basal Ganglia Output after Loss of Dopamine  

PubMed Central

The goal of the present study was to determine the phase relationships of the slow oscillatory activity that emerges in basal ganglia nuclei in anesthetized rats after dopamine cell lesion in order to gain insight into the passage of this oscillatory activity through the basal ganglia network. Spike train recordings from striatum, subthalamic nucleus (STN), globus pallidus (GP), and substantia nigra pars reticulata (SNpr) were paired with simultaneous local field potential (LFP) recordings from SNpr or motor cortex ipsilateral to a unilateral lesion of substantia nigra dopamine neurons in urethane anesthetized rats. Dopamine cell lesion induced a striking increase in incidence of slow oscillations (0.3-2.5 Hz) in firing rate in all nuclei. Phase relationships assessed through paired recordings using SNpr LFP as a temporal reference showed that slow oscillatory activity in GP spike trains is predominantly antiphase with oscillations in striatum, and slow oscillatory activity in STN spike trains is in-phase with oscillatory activity in cortex but predominantly antiphase with GP oscillatory activity. Taken together, these results imply that after dopamine cell lesion in urethane anesthetized rats, increased oscillatory activity in GP spike trains is shaped more by increased phasic inhibitory input from the striatum than by phasic excitatory input from STN. In addition, results show that oscillatory activity in SNpr spike trains is typically antiphase with GP oscillatory activity and in-phase with STN oscillatory activity. While these observations do not rule out additional mechanisms contributing to the emergence of slow oscillations in the basal ganglia after dopamine cell lesion in the anesthetized preparation, they are compatible with 1) increased oscillatory activity in the GP facilitated by an effect of dopamine loss on striatal ‘filtering’ of slow components of oscillatory cortical input, 2) increased oscillatory activity in STN spike trains supported by convergent antiphase inhibitory and excitatory oscillatory input from GP and cortex, respectively, and 3) increased oscillatory activity in SNpr spike trains organized by convergent antiphase inhibitory and excitatory oscillatory input from GP and STN, respectively. PMID:17112675

Walters, Judith R.; Hu, Dan; Itoga, Christy A.; Parr-Brownlie, Louise C.; Bergstrom, Debra A.

2007-01-01

251

Modulatory Effect of Acupuncture at Waiguan (TE5) on the Functional Connectivity of the Central Nervous System of Patients with Ischemic Stroke in the Left Basal Ganglia  

PubMed Central

Objective To study the influence of acupuncture at Waiguan (TE5) on the functional connectivity of the central nervous system of patients with ischemic stroke. Methods Twenty-four patients with ischemic stroke in the left basal ganglia were randomized based on gender to receive TE5 acupuncture (n?=?12) or nonacupoint acupuncture (n?=?12). Each group underwent sham acupuncture and then verum acupuncture while being scanned with functional magnetic resonance imaging. Six regions of interest (ROI) were defined, including bilateral motor, somatosensory, and bilateral basal ganglia areas. The functional connectivity between these ROIs and all voxels of the brain was analyzed in Analysis of Functional NeuroImages(AFNI) to explore the differences between verum acupuncture and sham acupuncture at TE5 and between TE5 acupuncture and nonacupoint acupuncture. The participants were blinded to the allocation. Result The effect of acupuncture on six seed-associated networks was explored. The result demonstrated that acupuncture at Waiguan (TE5) can regulate the sensorimotor network of the ipsilesional hemisphere, stimulate the contralesional sensorimotor network, increase cooperation of bilateral sensorimotor networks, and change the synchronization between the cerebellum and cerebrum. Furthermore, a lot of differences of effect existed between verum acupuncture and sham acupuncture at TE5, but there was little difference between TE5 acupuncture and nonacupoint acupuncture. Conclusion The modulation of synchronizations between different regions within different brain networks might be the mechanism of acupuncture at Waiguan (TE5). Stimulation of the contralesional sensorimotor network and increase of cooperation of bilateral hemispheres imply a compensatory effect of the intact hemisphere, whereas changes in synchronization might influence the sensorimotor function of the affected side of the body. Trial Registration Chinese Clinical Trial Registry ChiCTR-ONRC-08000255 PMID:24927275

Huang, Yong; Lai, Xinsheng; Tang, Chunzhi; Yang, Junjun; Wu, Junxian; Zeng, Tongjun; Qu, Shanshan

2014-01-01

252

Int J Comput Assist Radiol Surg . Author manuscript Automated segmentation of basal ganglia and deep brain structures in MRI  

E-print Network

movements and abnormal postures, to essential tremor or to Tourette syndrome. When pharmaceutical treatments,' and less frequently to dystonia that is a syndrome of sustained muscle contractions producing writhing

Paris-Sud XI, Université de

253

Population and computational analysis of the MGEA6 P521A variation as a risk factor for familial idiopathic basal ganglia calcification (Fahr's disease).  

PubMed

Familial idiopathic basal ganglia calcification, also known as "Fahr's disease" (FD), is a neuropsychiatric disorder with autosomal dominant pattern of inheritance and characterized by symmetric basal ganglia calcifications and, occasionally, other brain regions. Currently, there are three loci linked to this devastating disease. The first one (IBGC1) is located in 14q11.2-21.3 and the other two have been identified in 2q37 (IBGC2) and 8p21.1-q11.13 (IBGC3). Further studies identified a heterozygous variation (rs36060072) which consists in the change of the cytosine to guanine located at MGEA6/CTAGE5 gene, present in all of the affected large American family linked to IBGC1. This missense substitution, which induces changes of a proline to alanine at the 521 position (P521A), in a proline-rich and highly conserved protein domain was considered a rare variation, with a minor allele frequency (MAF) of 0.0058 at the US population. Considering that the population frequency of a given variation is an indirect indicative of potential pathogenicity, we screened 200 chromosomes in a random control set of Brazilian samples and in two nuclear families, comparing with our previous analysis in a US population. In addition, we accomplished analyses through bioinformatics programs to predict the pathogenicity of such variation. Our genetic screen found no P521A carriers. Polling these data together with the previous study in the USA, we have now a MAF of 0.0036, showing that this mutation is very rare. On the other hand, the bioinformatics analysis provided conflicting findings. There are currently various candidate genes and loci that could be involved with the underlying molecular basis of FD etiology, and other groups suggested the possible role played by genes in 2q37, related to calcium metabolism, and at chromosome 8 (NRG1 and SNTG1). Additional mutagenesis and in vivo studies are necessary to confirm the pathogenicity for variation in the P521A MGEA6. PMID:20838928

Lemos, Roberta R; Oliveira, Danyllo F; Zatz, Mayana; Oliveira, João R M

2011-03-01

254

Role of the human rostral supplementary motor area and the basal ganglia in motor sequence control: investigations with H2 15O PET.  

PubMed

The aim of this study was to investigate the functional anatomy of distributed cortical and subcortical motor areas in the human brain that participate in the central control of overlearned complex sequential unimanual finger movements. On the basis of previous research in nonhuman primates, a principal involvement of basal ganglia medial premotor loops [corrected] was predicted for central control of finger sequences performed automatically. In pertinent areas, a correlation of activation levels with the complexity of a motor sequence was hypothesized. H2 15O positron emission tomography (PET) was used in a group of seven healthy male volunteers [mean age 32.0 +/- 10.4 yr] to determine brain regions where levels of regional cerebral blood flow (rCBF) correlated with graded complexity levels of five different key-press sequences. All sequences were overlearned before PET and involved key-presses of fingers II-V of the right hand. Movements of individual fingers were kept constant throughout all five conditions by external pacing at 1-Hz intervals. Positive correlations of rCBF with increasing sequence complexity were identified in the contralateral rostral supplementary motor area (pre-SMA) and the associated pallido-thalamic loop, as well as in right parietal area 7 and ipsilateral primary motor cortex (M1). In contrast, while rCBF in contralateral M1 and [corrected] extensive parts of caudal SMA was increased compared with rest during task performance, significant correlated increases of rCBF with sequence complexity were not observed. Inverse correlations of rCBF with increasing sequence complexity were identified in mesial prefrontal-, medial temporal-, and anterior cingulate areas. The findings provide further evidence in humans supporting the notion of a segregation of SMA into functionally distinct subcomponents: although pre-SMA was differentially activated depending on the complexity of a sequence of learned finger movements, such modulation was not detectable in caudal SMA (except the most antero-superior part), implicating a motor executive role. Our observations of complexity-correlated rCBF increases in anterior globus pallidus suggest a specific role for the basal ganglia in the process of sequence facilitation and control. They may act to filter and focus input from motor cortical areas as patterns of action become increasingly complex. PMID:9463462

Boecker, H; Dagher, A; Ceballos-Baumann, A O; Passingham, R E; Samuel, M; Friston, K J; Poline, J; Dettmers, C; Conrad, B; Brooks, D J

1998-02-01

255

Manganese-Induced Atypical Parkinsonism Is Associated with Altered Basal Ganglia Activity and Changes in Tissue Levels of Monoamines in the Rat  

PubMed Central

Manganese neurotoxicity is associated with motor and cognitive disturbances known as Manganism. However, the mechanisms underlying these deficits remain unknown. Here we investigated the effects of manganese intoxication on motor and non-motor parkinsonian-like deficits such as locomotor activity, motor coordination, anxiety and “depressive-like” behaviors. Then, we studied the impact of this intoxication on the neuronal activity, the globus pallidus (GP) and subthalamic nucleus (STN). At the end of experiments, post-mortem tissue level of the three monoamines (dopamine, norepinephrine and serotonin) has been determined. The experiments were carried out in adult Sprague-Dawley rats, daily treated with MnCl2 (10 mg/kg/, i.p.) for 5 weeks. We show that manganese progressively reduced locomotor activity as well as motor coordination in parallel with the manifestation of anxiety and “depressive-like” behaviors. Electrophysiological results show that, while majority of GP and STN neurons discharged regularly in controls, manganese increased the number of GP and STN neurons discharging irregularly and/or with bursts. Biochemical results show that manganese significantly decreased tissue levels of norepinephrine and serotonin with increased metabolism of dopamine in the striatum. Our data provide evidence that manganese intoxication is associated with impaired neurotransmission of monoaminergic systems, which is at the origin of changes in basal ganglia neuronal activity and the manifestation of motor and non-motor deficits similar to those observed in atypical Parkinsonism. PMID:24896650

Bouabid, Safa; Delaville, Claire; De Deurwaerdère, Philippe; Lakhdar-Ghazal, Nouria; Benazzouz, Abdelhamid

2014-01-01

256

Projections from caudal ventrolateral prefrontal areas to brainstem preoculomotor structures and to Basal Ganglia and cerebellar oculomotor loops in the macaque.  

PubMed

The caudal part of the macaque ventrolateral prefrontal (VLPF) cortex hosts several distinct areas or fields-45B, 45A, 8r, caudal 46vc, and caudal 12r-connected to the frontal eye field (area 8/FEF). To assess whether these areas/fields also display subcortical projections possibly mediating a role in controlling oculomotor behavior, we examined their descending projections, based on anterograde tracer injections in each area/field, and compared them with those of area 8/FEF. All the studied areas/fields displayed projections to brainstem preoculomotor structures, precerebellar centers, and striatal sectors that are also targets of projections originating from area 8/FEF. Specifically, these projections involved: 1) the intermediate and superficial layers of the superior colliculus; 2) the mesencephalic and pontine reticular formation; 3) the dorsomedial and lateral pontine nuclei and the reticularis tegmenti pontis; and 4) the body of the caudate nucleus. Furthermore, area 45B projected also to the regions around the trochlear nucleus and to the raphe interpositus. The present data provide evidence for a role of the caudal VLPF areas/fields in controlling oculomotor behavior not only through their connections to area 8/FEF, but also in parallel through a direct access to preoculomotor brainstem structures and to the cerebellar and basal ganglia oculomotor loops. PMID:24068552

Borra, Elena; Gerbella, Marzio; Rozzi, Stefano; Luppino, Giuseppe

2015-03-01

257

Memory, Mood, Dopamine, and Serotonin in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-Lesioned Mouse Model of Basal Ganglia Injury  

PubMed Central

The 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-lesioned mouse serves as a model of basal ganglia injury and Parkinson’s disease. The present study investigated the effects of MPTP-induced lesioning on associative memory, conditioned fear, and affective behavior. Male C57BL/6 mice were administered saline or MPTP and separate groups were evaluated at either 7 or 30 days post-lesioning. In the social transmission of food preference test, mice showed a significant decrease in preference for familiar food 30 days post-MPTP compared to controls. Mice at both 7 and 30 days post-MPTP-lesioning had increased fear extinction compared to controls. HPLC analysis of tissues homogenates showed dopamine and serotonin were depleted in the striatum, frontal cortex, and amygdala. No changes in anxiety or depression were detected by the tail suspension, sucrose preference, light-dark preference, or hole-board tests. In conclusion, acute MPTP-lesioning regimen in mice causes impairments in associative memory and conditioned fear, no mood changes, and depletion of dopamine and serotonin throughout the brain. PMID:18718537

Vu?kovi?, Marta G.; Wood, Ruth I.; Holschneider, Daniel P.; Abernathy, Avery; Togasaki, Daniel M.; Smith, Alexsandra; Petzinger, Giselle M.; Jakowec, Michael W.

2012-01-01

258

Biotin-Responsive Basal Ganglia Disease Maps to 2q36.3 and Is Due to Mutations in SLC19A3  

PubMed Central

Biotin-responsive basal ganglia disease (BBGD) is a recessive disorder with childhood onset that presents as a subacute encephalopathy, with confusion, dysarthria, and dysphagia, and that progresses to severe cogwheel rigidity, dystonia, quadriparesis, and eventual death, if left untreated. BBGD symptoms disappear within a few days with the administration of high doses of biotin (5–10 mg/kg/d). On brain magnetic resonance imaging examination, patients display central bilateral necrosis in the head of the caudate, with complete or partial involvement of the putamen. All patients diagnosed to date are of Saudi, Syrian, or Yemeni ancestry, and all have consanguineous parents. Using linkage analysis in four families, we mapped the genetic defect near marker D2S2158 in 2q36.3 (LOD=5.9; ?=0.0) to a minimum candidate region (?2 Mb) between D2S2354 and D2S1256, on the basis of complete homozygosity. In this segment, each family displayed one of two different missense mutations that altered the coding sequence of SLC19A3, the gene for a transporter related to the reduced-folate (encoded by SLC19A1) and thiamin (encoded by SLC19A2) transporters. PMID:15871139

Zeng, Wen-Qi ; Al-Yamani, Eiman ; Acierno, Jr., James S. ; Slaugenhaupt, Susan ; Gillis, Tammy ; MacDonald, Marcy E. ; Ozand, Pinar T. ; Gusella, James F. 

2005-01-01

259

A De Novo Mutation in the ?-Tubulin Gene TUBB4A Results in the Leukoencephalopathy Hypomyelination with Atrophy of the Basal Ganglia and Cerebellum  

PubMed Central

Hypomyelination with atrophy of the basal ganglia and cerebellum (H-ABC) is a rare hereditary leukoencephalopathy that was originally identified by MRI pattern analysis, and it has thus far defied all attempts at identifying the causal mutation. Only 22 cases are published in the literature to date. We performed exome sequencing on five family trios, two family quartets, and three single probands, which revealed that all eleven H-ABC-diagnosed individuals carry the same de novo single-nucleotide TUBB4A mutation resulting in nonsynonymous change p.Asp249Asn. Detailed investigation of one of the family quartets with the singular finding of an H-ABC-affected sibling pair revealed maternal mosaicism for the mutation, suggesting that rare de novo mutations that are initially phenotypically neutral in a mosaic individual can be disease causing in the subsequent generation. Modeling of TUBB4A shows that the mutation creates a nonsynonymous change at a highly conserved asparagine that sits at the intradimer interface of ?-tubulin and ?-tubulin, and this change might affect tubulin dimerization, microtubule polymerization, or microtubule stability. Consistent with H-ABC’s clinical presentation, TUBB4A is highly expressed in neurons, and a recent report has shown that an N-terminal alteration is associated with a heritable dystonia. Together, these data demonstrate that a single de novo mutation in TUBB4A results in H-ABC. PMID:23582646

Simons, Cas; Wolf, Nicole I.; McNeil, Nathan; Caldovic, Ljubica; Devaney, Joseph M.; Takanohashi, Asako; Crawford, Joanna; Ru, Kelin; Grimmond, Sean M.; Miller, David; Tonduti, Davide; Schmidt, Johanna L.; Chudnow, Robert S.; van Coster, Rudy; Lagae, Lieven; Kisler, Jill; Sperner, Jürgen; van der Knaap, Marjo S.; Schiffmann, Raphael; Taft, Ryan J.; Vanderver, Adeline

2013-01-01

260

An extended reinforcement learning model of basal ganglia to understand the contributions of serotonin and dopamine in risk-based decision making, reward prediction, and punishment learning  

PubMed Central

Although empirical and neural studies show that serotonin (5HT) plays many functional roles in the brain, prior computational models mostly focus on its role in behavioral inhibition. In this study, we present a model of risk based decision making in a modified Reinforcement Learning (RL)-framework. The model depicts the roles of dopamine (DA) and serotonin (5HT) in Basal Ganglia (BG). In this model, the DA signal is represented by the temporal difference error (?), while the 5HT signal is represented by a parameter (?) that controls risk prediction error. This formulation that accommodates both 5HT and DA reconciles some of the diverse roles of 5HT particularly in connection with the BG system. We apply the model to different experimental paradigms used to study the role of 5HT: (1) Risk-sensitive decision making, where 5HT controls risk assessment, (2) Temporal reward prediction, where 5HT controls time-scale of reward prediction, and (3) Reward/Punishment sensitivity, in which the punishment prediction error depends on 5HT levels. Thus the proposed integrated RL model reconciles several existing theories of 5HT and DA in the BG. PMID:24795614

Balasubramani, Pragathi P.; Chakravarthy, V. Srinivasa; Ravindran, Balaraman; Moustafa, Ahmed A.

2014-01-01

261

Recurrent interactions between the input and output of a songbird cortico-basal ganglia pathway are implicated in vocal sequence variability  

PubMed Central

Complex brain functions, such as the capacity to learn and modulate vocal sequences, depend on activity propagation in highly distributed neural networks. To explore the synaptic basis of activity propagation in such networks, we made dual in vivo intracellular recordings in anesthetized zebra finches from the input (nucleus HVC) and output (lateral magnocellular nucleus of the anterior nidopallium (LMAN)) neurons of a songbird cortico-basal ganglia (BG) pathway necessary to the learning and modulation of vocal motor sequences. These recordings reveal evidence of bidirectional interactions, rather than only feedforward propagation of activity from HVC to LMAN, as had been previously supposed. A combination of dual and triple recording configurations and pharmacological manipulations was used to map out circuitry by which activity propagates from LMAN to HVC. These experiments indicate that activity travels to HVC through at least two independent ipsilateral pathways, one of which involves fast signaling through a midbrain dopaminergic cell group, reminiscent of recurrent mesocortical loops described in mammals. We then used in vivo pharmacological manipulations to establish that augmented LMAN activity is sufficient to restore high levels of sequence variability in adult birds, suggesting that recurrent interactions through highly distributed forebrain – midbrain pathways can modulate learned vocal sequences. PMID:22915110

Hamaguchi, Kosuke; Mooney, Richard

2012-01-01

262

AP1S2 is mutated in X-linked Dandy-Walker malformation with intellectual disability, basal ganglia disease and seizures (Pettigrew syndrome).  

PubMed

MRXS5 or Pettigrew syndrome was described 20 years ago in a four generation family including nine affected individuals presenting with facial dysmorphism, intellectual disability, Dandy-Walker malformation and inconstant choreoathetosis. Four individuals had iron deposition in the basal ganglia seen on MRI or at autopsy. The mutation causing Pettigrew has remained elusive since the initial description of the condition. We report the identification of a mutation in the X-linked AP1S2 gene in the original Pettigrew syndrome family using X-chromosome exome sequencing. We report additional phenotype details for several of the affected individuals, allowing us to further refine the phenotype corresponding to this X-linked intellectual disability syndrome. The AP1S2 c.426+1?G>T mutation segregates with the disease in the Pettigrew syndrome family and results in loss of 46 amino acids in the clathrin adaptor complex small chain domain that spans most of the AP1S2 protein sequence. The mutation reported here in AP1S2 is the first mutation that is not predicted to cause a premature termination of the coding sequence or absence of the AP1S2 protein. Although most of the families affected by a mutation in AP1S2 were initially described as having different disorders assigned to at least three different OMIM numbers (MIM 300629, 300630 and 304340), our analysis of the phenotype shows that they are all the same syndrome with recognition complicated by highly variable expressivity that is seen within as well as between families and is probably not explained by differences in mutation severity. PMID:23756445

Cacciagli, Pierre; Desvignes, Jean-Pierre; Girard, Nadine; Delepine, Marc; Zelenika, Diana; Lathrop, Mark; Lévy, Nicolas; Ledbetter, David H; Dobyns, William B; Villard, Laurent

2014-03-01

263

High-frequency stimulation of the subthalamic nucleus modifies the expression of vesicular glutamate transporters in basal ganglia in a rat model of Parkinson’s disease  

PubMed Central

Background It has been suggested that glutamatergic system hyperactivity may be related to the pathogenesis of Parkinson’s disease (PD). Vesicular glutamate transporters (VGLUT1-3) import glutamate into synaptic vesicles and are key anatomical and functional markers of glutamatergic excitatory transmission. Both VGLUT1 and VGLUT2 have been identified as definitive markers of glutamatergic neurons, but VGLUT 3 is also expressed by non glutamatergic neurons. VGLUT1 and VGLUT2 are thought to be expressed in a complementary manner in the cortex and the thalamus (VL/VM), in glutamatergic neurons involved in different physiological functions. Chronic high-frequency stimulation (HFS) of the subthalamic nucleus (STN) is the neurosurgical therapy of choice for the management of motor deficits in patients with advanced PD. STN-HFS is highly effective, but its mechanisms of action remain unclear. This study examines the effect of STN-HFS on VGLUT1-3 expression in different brain nuclei involved in motor circuits, namely the basal ganglia (BG) network, in normal and 6-hydroxydopamine (6-OHDA) lesioned rats. Results Here we report that: 1) Dopamine(DA)-depletion did not affect VGLUT1 and VGLUT3 expression but significantly decreased that of VGLUT2 in almost all BG structures studied; 2) STN-HFS did not change VGLUT1-3 expression in the different brain areas of normal rats while, on the contrary, it systematically induced a significant increase of their expression in DA-depleted rats and 3) STN-HFS reversed the decrease in VGLUT2 expression induced by the DA-depletion. Conclusions These results show for the first time a comparative analysis of changes of expression for the three VGLUTs induced by STN-HFS in the BG network of normal and hemiparkinsonian rats. They provide evidence for the involvement of VGLUT2 in the modulation of BG cicuits and in particular that of thalamostriatal and thalamocortical pathways suggesting their key role in its therapeutic effects for alleviating PD motor symptoms. PMID:24308494

2013-01-01

264

Eyeblink Conditioning Deficits Indicate Timing and Cerebellar Abnormalities in Schizophrenia  

ERIC Educational Resources Information Center

Accumulating evidence indicates that individuals with schizophrenia manifest abnormalities in structures (cerebellum and basal ganglia) and neurotransmitter systems (dopamine) linked to internal-timing processes. A single-cue tone delay eyeblink conditioning paradigm comprised of 100 learning and 50 extinction trials was used to examine cerebellar…

Brown, S.M.; Kieffaber, P.D.; Carroll, C.A.; Vohs, J.L.; Tracy, J.A.; Shekhar, A.; O'Donnell, B.F.; Steinmetz, J.E.; Hetrick, W.P.

2005-01-01

265

Evaluation of Basal Ganglia and Thalamic Inflammation in Children With Pediatric Autoimmune Neuropsychiatric Disorders Associated With Streptococcal Infection and Tourette Syndrome: A Positron Emission Tomographic (PET) Study Using 11C-[R]-PK11195.  

PubMed

We applied PET scanning with (11)C-[R]-PK11195 (PK) to evaluate neuroinflammatory changes in basal ganglia and thalamus in children with clinically diagnosed pediatric autoimmune neuropsychiatric disorders associated with streptococcal infection (PANDAS) and Tourette syndrome. Seventeen children with PANDAS (mean age: 11.4 ± 2.6 years; 13 males), 12 with Tourette syndrome (mean age: 11.0 ± 3.0 years; 10 males), and 15 normal adults (mean age: 28.7 ± 7.9 years; 8 males) underwent dynamic PK PET imaging and binding potential, a measure of ligand-TSPO receptor (expressed by activated microglia) binding, was calculated for basal ganglia and thalamus. Binding potential values, suggesting underlying activated microglia-mediated neuroinflammation, were found to be increased in bilateral caudate and bilateral lentiform nucleus in the PANDAS group and in bilateral caudate nuclei only in the Tourette syndrome group, compared to control group. These differences in the pattern and extent of neuroinflammation also signify a possible difference in pathophysiological etiology between PANDAS and Tourette syndrome patients. PMID:25117419

Kumar, Ajay; Williams, Mitchel T; Chugani, Harry T

2014-08-12

266

Analysis of gene expression pattern and neuroanatomical correlates for SLC20A2 (PiT-2) shows a molecular network with potential impact in idiopathic basal ganglia calcification ("Fahr's disease").  

PubMed

Familial idiopathic basal ganglia calcification (FIBGC), also known as "Fahr's disease," is a neuropsychiatric disorder with motor and cognitive symptoms. It is characterized pathologically by bilateral calcification most commonly in the basal ganglia and also in other brain regions such as the thalamus and cerebellum. A recent report by Wang et al. (2012) discovered multiple families with FIBGC carrying mutations in the SLC20A2 gene, encoding the inorganic phosphate transporter PiT-2, which segregated in an autosomal dominant pattern. To understand further the role of SLC20A2 in FIBGC brain pathology, here we described the gene expression pattern across the whole brain for SLC20A2, using the Allen Institute Human Brain Atlas database. Microarray analysis provided evidence that the neuroanatomical pattern of expression for SLC20A2 is highest in the regions most commonly affected in FIBGC. Neuroanatomical regions that demonstrated high correlation or anti-correlation with SLC20A2 expression also showed a molecular network with potential to explain the limited neuroanatomical distribution of calcifications in IBGC. Lastly, these co-expression networks suggest additional further candidate genes for FIBGC. PMID:23576097

da Silva, R J Galdino; Pereira, I C L; Oliveira, J R M

2013-06-01

267

Exclusion of linkage to chromosomes 14q, 2q37 and 8p21.1-q11.23 in a Serbian family with idiopathic basal ganglia calcification.  

PubMed

In this study we report clinical and imaging data from a multigenerational Serbian family with idiopathic basal ganglia calcification (IBGC) and exclusion of linkage to chromosome 14q, 2q37 and 8p21.1-q11.23. Fourteen out of 18 family members were personally examined and 11 of them were scanned with computed tomography (CT). CT scans revealed existence of symmetrical calcifications in six family members from three generations (four symptomatic and two asymptomatic). Age at onset of clinical symptoms varied between 22.0 and 55.4 years. The main clinical findings included parkinsonism, severe gait disturbances with freezing of gait, and dyskinesia. Hyperechogenicities identified by transcranial sonography corresponded well to the CT images of hyperintense calcifications in the same structures, whereas brain perfusion single photon emission computed tomography demonstrated predominant hypoperfusion in the frontal cortex and the basal ganglia. After exclusion of linkage to known loci, our pedigree with IBGC further demonstrates locus heterogeneity in this disorder. Analysis of clinically affected individuals supports observation that the clinical features of IBGC appear to be varied both within and between families. The age at onset of the clinical symptoms appeared to be decreasing in two observed transmissions, suggestive of possible genetic anticipation. PMID:21409505

Kosti?, Vladimir S; Luki?-Je?menica, Milica; Novakovi?, Ivana; Dobri?i?, Valerija; Brajkovi?, Lela; Krajinovi?, Maja; Klein, Christine; Pavlovi?, Aleksandra

2011-09-01

268

Selective inhibitory control and the basal ganglia  

E-print Network

RH"(1997)"CAG"repeat" number"governs"the"development"rate"of"pathology"in"Huntington's"disease."RH,#Stevens#TJ,#Ferrante#RJ,#Bird#ED,#Richardson#EP,#Jr. #(1985)# Neuropathological#classification#of#Huntington's#disease. #RH,#Stevens#TJ,#Ferrante#RJ,#Bird#ED,#Richardson#EP,#Jr. #(1985)# Neuropathological#classification#of#Huntington's#disease. #

Majid, Dewan-Syed Adnan

269

Functional anatomy of thalamus and basal ganglia  

Microsoft Academic Search

Thalamus. The human thalamus is a nuclear complex located in the diencephalon and comprising of four parts (the hypothalamus, the epythalamus, the ventral thalamus, and the dorsal thalamus). The thalamus is a relay centre subserving both sensory and motor mechanisms. Thalamic nuclei (50-60 nuclei) project to one or a few well-defined cortical areas. Multiple cortical areas receive afferents from a

María-Trinidad Herrero; Carlos Barcia; Juana Mari Navarro

2002-01-01

270

SEQUENTIAL MOTOR BEHAVIOR AND THE BASAL GANGLIA  

E-print Network

in monkeys Robert S. Turner, Kevin McCairn, Donn Simmons and Izhar Bar-Gad1 1.INTRODUCTION An important for the production of short familiar sequences (Verwey et al., 2002). 1 Robert S. Turner, Kevin McCain and Izhar Bar

Bar-Gad, Izhar

271

Cerebral abnormalities: use of calculated T1 and T2 magnetic resonance images for diagnosis  

SciTech Connect

The potential clinical importance of T1 and T2 relaxation times in distinguishing normal and pathologic tissue with magnetic resonance (MR) is discussed and clinical examples of cerebral abnormalities are given. Five patients with cerebral infarction, 15 with multiple sclerosis, two with Wilson disease, and four with tumors were imaged. Hemorrhagic and ischemic cerebrovascular accidents were distinguished using the spin echo technique. In the patients with multiple sclerosis, lesions had prolonged T1 and T2 times, but the definition of plaque was limited by spatial resolution. No abnormalities in signal intensity were seen in the patient with Wilson disease who was no longer severly disabled; abnormal increased signal intensity in the basal ganglia was found in the second patient with Wilson disease. Four tumors produced abnormal T1 and T2 relaxation times but these values alone were not sufficient for tumor characterization.

Mills, C.M.; Crooks, L.E.; Kaufman, L.; Brant-Zawadzki, M.

1984-01-01

272

Abnormal iron homeostasis and neurodegeneration  

PubMed Central

Abnormal iron metabolism is observed in many neurodegenerative diseases, however, only two have shown dysregulation of brain iron homeostasis as the primary cause of neurodegeneration. Herein, we review one of these - hereditary ferritinopathy (HF) or neuroferritinopathy, which is an autosomal dominant, adult onset degenerative disease caused by mutations in the ferritin light chain (FTL) gene. HF has a clinical phenotype characterized by a progressive movement disorder, behavioral disturbances, and cognitive impairment. The main pathologic findings are cystic cavitation of the basal ganglia, the presence of ferritin inclusion bodies (IBs), and substantial iron deposition. Mutant FTL subunits have altered sequence and length but assemble into soluble 24-mers that are ultrastructurally indistinguishable from those of the wild type. Crystallography shows substantial localized disruption of the normally tiny 4-fold pores between the ferritin subunits because of unraveling of the C-termini into multiple polypeptide conformations. This structural alteration causes attenuated net iron incorporation leading to cellular iron mishandling, ferritin aggregation, and oxidative damage at physiological concentrations of iron and ascorbate. A transgenic murine model parallels several features of HF, including a progressive neurological phenotype, ferritin IB formation, and misregulation of iron metabolism. These studies provide a working hypothesis for the pathogenesis of HF by implicating (1) a loss of normal ferritin function that triggers iron accumulation and overproduction of ferritin polypeptides, and (2) a gain of toxic function through radical production, ferritin aggregation, and oxidative stress. Importantly, the finding that ferritin aggregation can be reversed by iron chelators and oxidative damage can be inhibited by radical trapping may be used for clinical investigation. This work provides new insights into the role of abnormal iron metabolism in neurodegeneration. PMID:23908629

Muhoberac, Barry B.; Vidal, Ruben

2013-01-01

273

Light-Induced Alterations in Basil Ganglia Kynurenic Acid Levels  

NASA Technical Reports Server (NTRS)

The metabolic synthesis, release and breakdown of several known CNS neurotransmitters have been shown to follow a circadian pattern entrained to the environmental light/dark cycle. The levels of excitatory amino acid (EAA) transmitters such as glutamate, have been shown to vary with environmental lighting conditions. Kynurenic Acid (KA), an endogenous tryptophan metabolite and glutamate receptor antagonist, has been reported to have neuroprotective effects against EAA-induced excitotoxic cell damage. Changes in KA's activity within the mammalian basal ganglia has been proposed as being contributory to neurotoxicity in Huntington's Disease. It is not known whether CNS KA levels follow a circadian pattern or exhibit light-induced fluctuations. However, because the symptoms of certain degenerative motor disorders seem to fluctuate with daily 24 hour rhythm, we initiated studies to determine if basal ganglia KA were influenced by the daily light/dark cycle and could influence motor function. Therefore in this study, HPLC-EC was utilized to determine if basal ganglia KA levels in tissue extracts from adult male Long-Evans rats (200-250g) entrained to 24 and 48 hours constant light and dark conditions, respectively. Samples were taken one hour before the onset of the subjective day and one hour prior to the onset of the subjective night in order to detect possible phase differences in KA levels and to allow for accumulation of factors expressed in association with the light or dark phase. Data analysis revealed that KA levels in the basal ganglia vary with environmental lighting conditions; being elevated generally during the dark. Circadian phase differences in KA levels were also evident during the subjective night and subjective day, respectively. Results from these studies are discussed with respect to potential cyclic changes in neuronal susceptibility to excitotoxic damage during the daily 24 hour cycle and its possible relevance to future therapeutic approaches in treating neurodegenerative disorders.

Sroufe, Angela E.; Whittaker, J. A.; Patrickson, J. W.; Orr, M. C.

1997-01-01

274

The Basal Ganglia Mahlon R. DeLong  

E-print Network

examination of patients with Parkinson disease, Huntington disease, and hemiballismus revealed pathological diminished movement (as in Parkinson disease) or excessive movement (as in Huntington disease). In addition in clinical neurology. Parkinson disease was the first disease of the nervous system to be identified

275

Hemi-dystonia secondary to localised basal ganglia tumour.  

PubMed Central

An 8-year-old boy with an 18 month history of left limb hemi-dystonia due to a right lenticular nucleus astrocytoma originating in the putamen is reported. Subsequent neuropathological study demonstrated that the tumour was mainly localised to the right lenticular nucleus, with cystic necrosis in the infero-lateral putamen. Solid tumour also infiltrated the right hypothalamus, the anterior commisure and the optic chiasm, and there was perivascular spread into the globus pallidus, internal capsule and roof of the right lateral ventricle. This case, and the few other published reports of symptomatic dystonia due to focal brain lesions verified pathologically, indicate that damage to the lenticular nucleus, and to the putamen in particular, can cause limb dystonia in man. Images PMID:6747646

Narbona, J; Obeso, J A; Tuñon, T; Martinez-Lage, J M; Marsden, C D

1984-01-01

276

Basal Ganglia Engagement during Feedback Processing after a Substantial Delay  

PubMed Central

The striatum has been shown to play an important role in learning from performance-related feedback that is presented shortly after each response. However, less is known about the neural mechanisms supporting learning from feedback that is substantially delayed from the original response. Since the consequences of one’s actions often do not become known until after a delay, it is important to understand whether delayed feedback can produce neural responses similar to those elicited by immediate feedback presentation. We investigated this issue by using functional magnetic resonance imaging (fMRI) as participants performed a paired-associate learning task with 180 distinct trials. Feedback indicating response accuracy was presented immediately, after a delay of 25 minutes, or not at all. Both immediate and delayed feedback led to significant gains in accuracy on a post-test, relative to no feedback. Replicating previous work, we found that the caudate nuclei showed greater activation for positive feedback than negative feedback when the feedback was presented immediately. In addition, delayed feedback also led to differential caudate activity to positive versus negative feedback. Delayed negative feedback also produced significant activation of the putamen and globus pallidus (the lentiform nucleus), relative to no feedback and delayed positive feedback. This suggests that the caudate nucleus is sensitive to the affective nature of feedback, across different timescales, while the lentiform nucleus may be particularly involved in processing the information carried by negative feedback after a substantial delay. PMID:23817894

Dobryakova, Ekaterina; Tricomi, Elizabeth

2013-01-01

277

Basal ganglia engagement during feedback processing after a substantial delay.  

PubMed

The striatum has been shown to play an important role in learning from performance-related feedback that is presented shortly after each response. However, less is known about the neural mechanisms supporting learning from feedback that is substantially delayed from the original response. Since the consequences of one's actions often do not become known until after a delay, it is important to understand whether delayed feedback can produce neural responses similar to those elicited by immediate-feedback presentation. We investigated this issue by using functional magnetic resonance imaging (fMRI) as participants performed a paired-associate learning task with 180 distinct trials. Feedback indicating response accuracy was presented immediately, after a delay of 25 min, or not at all. Both immediate and delayed feedback led to significant gains in accuracy on a posttest, relative to no feedback. Replicating previous work, we found that the caudate nuclei showed greater activation for positive feedback than for negative feedback when the feedback was presented immediately. In addition, delayed feedback also led to differential caudate activity to positive versus negative feedback. Delayed negative feedback also produced significant activation of the putamen and globus pallidus (the lentiform nucleus), relative to no feedback and delayed positive feedback. This suggests that the caudate nucleus is sensitive to the affective nature of feedback, across different time scales, while the lentiform nucleus may be particularly involved in processing the information carried by negative feedback after a substantial delay. PMID:23817894

Dobryakova, Ekaterina; Tricomi, Elizabeth

2013-12-01

278

ANATOMY REVIEW: Basal Ganglia A group of subcortical nuclei  

E-print Network

akinesia Resting tremor Shrinkage of handwriting, bradykinesia, athetosis medicated non-medicated #12;4 See deterioration of dopaminergic cells in substantia nigra · Normally lose a bit every year due to aging · genetic, deterioration of caudate nucleus (arrows) healthy #12;5 · These dyskinesias suggest

Sergio, Lauren E.

279

Electrophysiological Effects of Cannabinoids in the Basal Ganglia  

Microsoft Academic Search

\\u000a The hemp plant contains more than 416 chemicals of which more than 60 are cannabinoids (Turner. 1984). These compounds have\\u000a been known for their therapeutic and psychoactive properties for at least 4000 years. The principal rleuroactive constituent\\u000a is ?9-tetrahydrocannabinol (?9-TAC), often used as the prototype of the entire cannabinoid family due to its presence in derivatives ofcannabis sativa(marijuana and hashish)

Anna Lisa Muntoni; Miriam Melis; Marco Diana

280

Humanized Foxp2 specifically affects cortico-basal ganglia circuits  

Microsoft Academic Search

It has been proposed that two amino acid substitutions in the transcription factor FOXP2 have been positively selected during human evolution and influence aspects of speech and language. Recently it was shown that when these substitutions are introduced into the endogenous Foxp2 gene of mice, they increase dendrite length and long-term depression (LTD) in medium spiny neurons of the striatum.

S. Reimers-Kipping; W. Hevers; S. Pääbo; W. Enard

2011-01-01

281

CODING OF BEHAVIORAL SEQUENCES IN THE BASAL GANGLIA  

E-print Network

to control kinematic and dynamic features of movement such as force and direction; however, their difficulty, the highly stereotyped sequence of grooming in rodents behavior that we will examine in this study has

Berridge, Kent

282

CODING OF BEHAVIORAL SEQUENCES IN THE BASAL GANGLIA  

E-print Network

to control kinematic and dynamic features of movement such as force and direction; however, their difficulty. For example, the highly stereotyped sequence of grooming in rodents behavior that we will examine

Berridge, Kent

283

Habenula - Crossroad between the Basal Ganglia and the Limbic System  

PubMed Central

There is a growing awareness that emotion, motivation, and reward values are important determinants of our behavior. The habenula is uniquely positioned both anatomically and functionally to participate in the circuit mediating some forms of emotive decision-making. In the last few years there has been a surge of interest in this structure, especially the lateral habenula (LHb). The new studies suggest that the LHb plays a pivotal role in controlling motor and cognitive behaviors by influencing the activity of dopamine (DA) and serotonin neurons. Further, dysfunctions of the LHb have also been implicated in psychiatric disorders, such as depression, schizophrenia, and drug-induced psychosis. PMID:19005047

Hikosaka, Okihide; Sesack, Susan R; Lecourtier, Lucas; Shepard, Paul D.

2008-01-01

284

Synchronous Oscillations in the Basal-Ganglia-Cortical Network  

E-print Network

(PD) are akinesia (poverty of spontaneous movements and difficulty in initiating a movement in the spike-train, since any increase in the discharge rate causes a decrease in subsequent time-bins, leading

285

Basal cell carcinoma  

MedlinePLUS

Basal cell skin cancer; Rodent ulcer; Skin cancer - basal cell; Cancer - skin - basal cell; Nonmelanoma skin cancer; Basal cell NMSC ... Basal cell cancer starts in the top layer of the skin called the epidermis. Most basal cell cancers occur ...

286

Basal Cell Carcinoma  

MedlinePLUS

... and treatments A - D Basal cell carcinoma Basal cell carcinoma Basal cell carcinoma: This skin cancer often ... skin tissue and bone. Learn more about basal cell carcinoma: Basal cell carcinoma: Signs and symptoms Basal ...

287

Basal cell nevus syndrome - close-up of palm (image)  

MedlinePLUS

... skeletal abnormalities. Skin manifestations include pits in the palms and soles, and numerous basal cell carcinomas. This ... close-up of the pits found in the palm of an individual with basal cell nevus syndrome.

288

Cerebral metabolite abnormalities in human immunodeficiency virus are associated with cortical and subcortical volumes.  

PubMed

Cerebral metabolite disturbances occur among human immunodeficiency virus (HIV)-infected people, and are thought to reflect neuropathology, including proinflammatory processes, and neuronal loss. HIV-associated cortical atrophy continues to occur, though its basis is not well understood, and the relationship of cerebral metabolic disturbance to structural brain abnormalities in HIV has not been well delineated. We hypothesized that metabolite disturbances would be associated with reduced cortical and subcortical volumes. Cerebral volumes were measured in 67 HIV-infected people, including 10 people with mild dementia (acquired immunodeficiency syndrome [AIDS] dimentia complex [ADC] stage >1) via automated magnetic resonance imaging (MRI) segmentation. Magnetic resonance spectroscopy (MRS) was used to measure levels of cerebral metabolites N-acetylaspartate (NAA), myo-inositol (MI), choline-containing compounds (Cho), glutamate/glutamine (Glx), and creatine (Cr) from three brain regions (frontal gray matter, frontal white matter, basal ganglia). Analyses were conducted to examine the associations between MRS and cerebral volumetric measures using both absolute and relative metabolite concentrations. NAA in the mid-frontal gray matter was most consistently associated with cortical (global, frontal, and parietal), ventricular, and caudate volumes based on analysis of absolute metabolite levels, whereas temporal lobe volume was associated with basal ganglia NAA and Glx, and Cho concentrations in the frontal cortex and basal ganglia. Hippocampal volume was associated with frontal white matter NAA, whereas thalamic volume was associated with both frontal white matter NAA and basal ganglia Glx. Analyses of relative metabolite concentrations (referenced to Cr) yielded weaker effects, although more metabolites were retained as significant predictors in the models than the analysis of absolute concentrations. These findings demonstrate that reduced cortical and subcortical volumes, which have been previously found to be linked to HIV status and history, are also strongly associated with the degree of cerebral metabolite disturbance observed via MRS. Reduced cortical and hippocampal volumes were most strongly associated with decreased NAA, though reduced Glx also tended to be associated with reduced cortical and subcortical volumes (caudate and thalamus) as well, suggesting both neuronal and glial disturbances. Interestingly, metabolite-volumetric relationships were not limited to the cortical region from which MRS was measured, possibly reflecting shared pathophysiological processes. The relationships between Cho and volumetric measures suggest a complicated relationship possibly related to the effects of inflammatory processes on brain volume. The findings demonstrate the relationship between MRI-derived measures of cerebral metabolite disturbances and structural brain integrity, which has implication in understanding HIV-associated neuropathological mechanisms. PMID:20961212

Cohen, Ronald A; Harezlak, Jaroslaw; Gongvatana, Assawin; Buchthal, Steven; Schifitto, Giovanni; Clark, Uraina; Paul, Robert; Taylor, Michael; Thompson, Paul; Tate, David; Alger, Jeffery; Brown, Mark; Zhong, Jianhui; Campbell, Thomas; Singer, Elyse; Daar, Eric; McMahon, Deborah; Tso, Yuen; Yiannoutsos, Constantin T; Navia, Bradford

2010-11-01

289

Corticobasal ganglia circuit mechanism for a decision threshold in reaction time tasks  

E-print Network

Cortico­basal ganglia circuit mechanism for a decision threshold in reaction time tasks Chung that in reaction time tasks, a perceptual choice is made when the firing rate of a selective cortical neural to describe the main computational steps in a reaction time task and suggests that separate brain pathways

Wang, Xiao-Jing

290

Bilateral basal ganglion haemorrhage in diabetic ketoacidotic coma: case report  

Microsoft Academic Search

We report bilateral oedema and haemorrhagic transformation in the basal ganglia of a 59-year old woman with severe diabetic\\u000a ketoacidosis. Lack of cerebral vascular autoregulation, followed by blood-brain barrier disruption due to the so-called breakthrough\\u000a mechanism is presumed to be the cause.

B. Ertl-Wagner; O. Jansen; S. Schwab; K. Sartor

1999-01-01

291

Structural, Metabolic, and Functional Brain Abnormalities as a Result of Prenatal Exposure to Drugs of Abuse: Evidence from Neuroimaging  

PubMed Central

Prenatal exposure to alcohol and stimulants negatively affects the developing trajectory of the central nervous system in many ways. Recent advances in neuroimaging methods have allowed researchers to study the structural, metabolic, and functional abnormalities resulting from prenatal exposure to drugs of abuse in living human subjects. Here we review the neuroimaging literature of prenatal exposure to alcohol, cocaine, and methamphetamine. Neuroimaging studies of prenatal alcohol exposure have reported differences in the structure and metabolism of many brain systems, including in frontal, parietal, and temporal regions, in the cerebellum and basal ganglia, as well as in the white matter tracts that connect these brain regions. Functional imaging studies have identified significant differences in brain activation related to various cognitive domains as a result of prenatal alcohol exposure. The published literature of prenatal exposure to cocaine and methamphetamine is much smaller, but evidence is beginning to emerge suggesting that exposure to stimulant drugs in utero may be particularly toxic to dopamine-rich basal ganglia regions. Although the interpretation of such findings is somewhat limited by the problem of polysubstance abuse and by the difficulty of obtaining precise exposure histories in retrospective studies, such investigations provide important insights into the effects of drugs of abuse on the structure, function, and metabolism of the developing human brain. These insights may ultimately help clinicians develop better diagnostic tools and devise appropriate therapeutic interventions to improve the condition of children with prenatal exposure to drugs of abuse. PMID:20978945

Roussotte, Florence; Soderberg, Lindsay

2010-01-01

292

Seizure-induced brain lesions: a wide spectrum of variably reversible MRI abnormalities.  

PubMed

Introduction MRI abnormalities in the postictal period might represent the effect of the seizure activity, rather than its structural cause. Material and Methods Retrospective review of clinical and neuroimaging charts of 26 patients diagnosed with seizure-related MR-signal changes. All patients underwent brain-MRI (1.5-Tesla, standard pre- and post-contrast brain imaging, including DWI-ADC in 19/26) within 7 days from a seizure and at least one follow-up MRI, showing partial or complete reversibility of the MR-signal changes. Extensive clinical work-up and follow-up, ranging from 3 months to 5 years, ruled out infection or other possible causes of brain damage. Seizure-induced brain-MRI abnormalities remained a diagnosis of exclusion. Site, characteristics and reversibility of MRI changes, and association with characteristics of seizures were determined. Results MRI showed unilateral (13/26) and bilateral abnormalities, with high (24/26) and low (2/26) T2-signal, leptomeningeal contrast-enhancement (2/26), restricted diffusion (9/19). Location of abnormality was cortical/subcortical, basal ganglia, white matter, corpus callosum, cerebellum. Hippocampus was involved in 10/26 patients. Reversibility of MRI changes was complete in 15, and with residual gliosis or focal atrophy in 11 patients. Reversibility was noted between 15 and 150 days (average, 62 days). Partial simple and complex seizures were associated with hippocampal involvement (p=0.015), status epilepticus with incomplete reversibility of MRI abnormalities (p=0.041). Conclusions Seizure or epileptic status can induce transient, variably reversible MRI brain abnormalities. Partial seizures are frequently associated with hippocampal involvement and status epilepticus with incompletely reversible lesions. These seizure-induced MRI abnormalities pose a broad differential diagnosis; increased awareness may reduce the risk of misdiagnosis and unnecessary intervention. PMID:23787273

Cianfoni, A; Caulo, M; Cerase, A; Della Marca, G; Falcone, C; Di Lella, G M; Gaudino, S; Edwards, J; Colosimo, C

2013-11-01

293

Communication between neuronal somata and satellite glial cells in sensory ganglia.  

PubMed

Studies of the structural organization and functions of the cell body of a neuron (soma) and its surrounding satellite glial cells (SGCs) in sensory ganglia have led to the realization that SGCs actively participate in the information processing of sensory signals from afferent terminals to the spinal cord. SGCs use a variety ways to communicate with each other and with their enwrapped soma. Changes in this communication under injurious conditions often lead to abnormal pain conditions. "What are the mechanisms underlying the neuronal soma and SGC communication in sensory ganglia?" and "how do tissue or nerve injuries affect the communication?" are the main questions addressed in this review. PMID:23918214

Huang, Li-Yen M; Gu, Yanping; Chen, Yong

2013-10-01

294

Structural brain abnormalities in cervical dystonia  

PubMed Central

Background Idiopathic cervical dystonia is characterized by involuntary spasms, tremors or jerks. It is not restricted to a disturbance in the basal ganglia system because non-conventional voxel-based MRI morphometry (VBM) and diffusion tensor imaging (DTI) have detected numerous regional changes in the brains of patients. In this study scans of 24 patients with cervical dystonia and 24 age-and sex-matched controls were analysed using VBM, DTI and magnetization transfer imaging (MTI) using a voxel-based approach and a region-of-interest analysis. Results were correlated with UDRS, TWSTRS and disease duration. Results We found structural alterations in the basal ganglia; thalamus; motor cortex; premotor cortex; frontal, temporal and parietal cortices; visual system; cerebellum and brainstem of the patients with dystonia. Conclusions Cervical dystonia is a multisystem disease involving several networks such as the motor, sensory and visual systems. PMID:24131497

2013-01-01

295

Glucose6Phosphate Dehydrogenase Activity in Dorsal Root Ganglia of Vitamin E-Deficient Rats  

Microsoft Academic Search

The effect of dietary vitamin E on the activity of glucose-6-phosphate dehydrogenase (G6PD) and 6-phosphogluconate dehydrogenase (6PGD) was studied in the dorsal root ganglia of rat. One-month-old male Sprague-Dawley rats were randomly assigned to two dietary treatment groups for 2 months. The first received a standard diet supplemented with vitamin E, the second was fed a basal vitamin E-deficient diet.

P. Ninfali; C. Cuppini; R. Cuppini; S. Rapa; L. Baronciani

1991-01-01

296

Abuse of Amphetamines and Structural Abnormalities in Brain  

PubMed Central

We review evidence that structural brain abnormalities are associated with abuse of amphetamines. A brief history of amphetamine use/abuse, and evidence for toxicity is followed by a summary of findings from structural magnetic resonance imaging (MRI) studies of human subjects who had abused amphetamines and children who were exposed to amphetamines in utero. Evidence comes from studies that used a variety of techniques that include manual tracing, pattern matching, voxel-based, tensor-based, or cortical thickness mapping, quantification of white matter signal hyperintensities, and diffusion tensor imaging. Ten studies compared controls to individuals who were exposed to methamphetamine. Three studies assessed individuals exposed to 3-4-methylenedioxymethamphetamine (MDMA). Brain structural abnormalities were consistently reported in amphetamine abusers, as compared to control subjects. These included lower cortical gray matter volume and higher striatal volume than control subjects. These differences might reflect brain features that could predispose to substance dependence. High striatal volumes might also reflect compensation for toxicity in the dopamine-rich basal ganglia. Prenatal exposure was associated with striatal volume that was below control values, suggesting that such compensation might not occur in utero. Several forms of white matter abnormality are also common, and may involve gliosis. Many of the limitations and inconsistencies in the literature relate to techniques and cross-sectional designs, which cannot infer causality. Potential confounding influences include effects of pre-existing risk/protective factors, development, gender, severity of amphetamine abuse, abuse of other drugs, abstinence, and differences in lifestyle. Longitudinal designs in which multimodal datasets are acquired and are subjected to multivariate analyses would enhance our ability to provide general conclusions regarding the associations between amphetamine abuse and brain structure. PMID:18991959

Berman, Steven; O’Neill, Joseph; Fears, Scott; Bartzokis, George; London, Edythe D.

2009-01-01

297

Meiotic abnormalities  

SciTech Connect

Chapter 19, describes meiotic abnormalities. These include nondisjunction of autosomes and sex chromosomes, genetic and environmental causes of nondisjunction, misdivision of the centromere, chromosomally abnormal human sperm, male infertility, parental age, and origin of diploid gametes. 57 refs., 2 figs., 1 tab.

NONE

1993-12-31

298

Incomplete and Inaccurate Vocal Imitation after Knockdown of FoxP2 in Songbird Basal  

E-print Network

developmental verbal dyspraxia (DVD), a speech and language disorder that compromises the fluent production deficits [1­4]. Brain imaging studies in adult FOXP2 patients implicate the basal ganglia as key affected with the incorporation of most new syllables to their seasonally changing song [10]. FoxP2 is down-regulated in Area X

Scharff, Constance

299

Congenital Abnormalities  

MedlinePLUS

... Ask your pediatrician for a referral to a genetic counseling service . These services have expertise with a variety ... Family Health History & Genetics Detecting Genetic Abnormalities Prenatal Genetic Counseling Children with Down Syndrome: Health Care Information for ...

300

Quantitative Assessment of Motor Abnormalities in Untreated Patients with Major Depressive Disorder  

PubMed Central

The primary purpose of this study was to examine motor physiology disturbances in a group of patients with untreated major depressive disorder using sensitive instrumental procedures. The secondary aim of the study was to examine the relationship of the affective symptom state to these motor assessments. The authors studied 40 individuals meeting DSM-IV criteria for unipolar major depressive disorder and 40 healthy comparison subjects. Electromechanical measures of force steadiness (FS), simple reaction time (RT), movement time (MT) and scaling of movement velocity to distance (velocity scaling, VS) were performed. The authors found that performance on the force steadiness, movement time, and velocity scaling measures was significantly poorer in the subjects with depression. There was no difference between the groups on the measure of reaction time. The force steadiness, reaction time, movement time, and velocity scaling scores were not associated with affective state. This study demonstrates that motor abnormalities suggestive of basal ganglia dysfunction occur in many patients with major depressive disorder, and that these abnormalities may exist in the absence of current psychotropic medication treatment. The finding of impaired movement time and velocity scaling in the presence of normal reaction time suggests a neuromotor or parkinsonian pathophysiology for slowness in depression. PMID:22985485

Lohr, James B.; May, Todd; Caligiuri, Michael P.

2014-01-01

301

Abnormal high-frequency burst firing of cerebellar neurons in rapid-onset dystonia-parkinsonism.  

PubMed

Loss-of-function mutations in the ?3 isoform of the Na(+)/K(+) ATPase (sodium pump) are responsible for rapid-onset dystonia parkinsonism (DYT12). Recently, a pharmacological model of DYT12 was generated implicating both the cerebellum and basal ganglia in the disorder. Notably, partially blocking sodium pumps in the cerebellum was necessary and sufficient for induction of dystonia. Thus, a key question that remains is how partially blocking sodium pumps in the cerebellum induces dystonia. In vivo recordings from dystonic mice revealed abnormal high-frequency bursting activity in neurons of the deep cerebellar nuclei (DCN), which comprise the bulk of cerebellar output. In the same mice, Purkinje cells, which provide strong inhibitory drive to DCN cells, also fired in a similarly erratic manner. In vitro studies demonstrated that Purkinje cells are highly sensitive to sodium pump dysfunction that alters the intrinsic pacemaking of these neurons, resulting in erratic burst firing similar to that identified in vivo. This abnormal firing abates when sodium pump function is restored and dystonia caused by partial block of sodium pumps can be similarly alleviated. These findings suggest that persistent high-frequency burst firing of cerebellar neurons caused by sodium pump dysfunction underlies dystonia in this model of DYT12. PMID:25164667

Fremont, Rachel; Calderon, D Paola; Maleki, Sara; Khodakhah, Kamran

2014-08-27

302

[Seizures revealing phosphocalcic metabolism abnormalities].  

PubMed

Hypocalcemia due to hypoparathyroidism produces a broad spectrum of clinical manifestations, but overt symptoms may be sparse. One unusual presentation is onset or aggravation of epilepsy in adolescence revealing hypoparathyroidism. This situation can lead to delayed diagnosis, with inefficacity of the antiepileptic drugs. We report five cases of adolescence-onset epilepsy with unsuccessful antiepileptic therapy, even with gradually increasing dose. Physical examination revealed signs of hypocalcemia, confirmed biologically. Full testing disclosed the origin of the seizures: hypoparathyroidism in three patients and pseudohypoparathyroidism in the other two. In four of five patients, computed tomography showed calcification of the basal ganglia, defining Fahr's syndrome. The patients were treated with oral calcium and active vitamin D (1-alphahydroxy vitamin D3). Seizure frequency progressively decreased and serum calcium levels returned to normal. These cases illustrate the importance of the physical examination and of routine serum calcium assay in patients with new-onset epileptic seizures in order to detect hypocalcemia secondary to hypoparathyroidism. PMID:24726042

Hmami, F; Chaouki, S; Benmiloud, S; Souilmi, F Z; Abourazzak, S; Idrissi, M; Atmani, S; Bouharrou, A; Hida, M

2014-01-01

303

Psychosocial stress-induced hypertension results from in vivo expression of long-term potentiation in rat sympathetic ganglia  

Microsoft Academic Search

Long-term potentiation in sympathetic ganglia (gLTP) is an activity-dependent unique form of synaptic plasticity in that it is serotonin-dependent and can be completely inhibited by 5-HT3 receptor antagonists. Long lasting enhancement of the basal tone of ganglionic transmission seen with gLTP results in a sustained increase in peripheral resistance that leads to elevated blood pressure. We examined the possibility that,

Karim A. Alkadhi; Karem H. Alzoubi; Abdulaziz M. Aleisa; Felicia L. Tanner; Ayad S. Nimer

2005-01-01

304

Tracheal Basal Cells  

PubMed Central

Analysis of lineage relationships in the naphthalene-injured tracheal epithelium demonstrated that two multipotential keratin 14–expressing cells (K14ECs) function as progenitors for Clara and ciliated cells. These K14EC were distinguished by their self-renewal capacity and were hypothesized to reside at the stem and transit amplifying tiers of a tissue-specific stem cell hierarchy. In this study, we used gene expression and histomorphometric analysis of the steady-state and naphthalene-injured trachea to evaluate the predictions of this model. We found that the steady-state tracheal epithelium is maintained by two progenitor cell pools, secretory and basal cells, and the latter progenitor pool is further divided into two subsets, keratin 14–negative and –positive. After naphthalene-mediated depletion of the secretory and ciliated cell types, the two basal cell pools coordinate to restore the epithelium. Both basal cell types up-regulate keratin 14 and generate a broadly distributed, abundant, and highly mitotic cell pool. Furthermore, basal cell proliferation is associated with generation of differentiated Clara and ciliated cells. The uniform distribution of basal cell progenitors and of their differentiated progeny leads us to propose that the hierarchical organization of tracheal reparative cells be revised to include a facultative basal cell progenitor pool. PMID:20522644

Cole, Brook B.; Smith, Russell W.; Jenkins, Kimberly M.; Graham, Brian B.; Reynolds, Paul R.; Reynolds, Susan D.

2010-01-01

305

Calmodulin and guanylyl cyclase inhibitors block the in vivo expression of gLTP in sympathetic ganglia from chronically stressed rats.  

PubMed

Previous work from this laboratory indicated that superior cervical ganglia from rats exposed to chronic psychosocial stress expressed ganglionic long-term potentiation (gLTP) in vivo. In the present study, we report additional pharmacological evidence indicating involvement of calmodulin and guanylyl cyclase in gLTP, and supporting the in vivo gLTP expression in ganglia from chronically stressed rats. Pretreatment with the calmodulin inhibitors W-7 (5 microM) or calmidazolium (5 microM) or with guanylyl cyclase inhibitor LY-83583 (5 microM) completely blocked HFS (20 Hz/20s)-induced gLTP in superior cervical ganglia isolated from normal rats. Along with that, inhibition of apparent basal ganglionic transmission by W-7 (5 microM), calmidazolium (5 microM) or LY-83583 (5 microM) is observed in ganglia isolated from chronically stressed rats, but not in those from control rats, indicating in vivo expression of gLTP in ganglia isolated from stressed rats. The present results confirm the involvement of both calmodulin and GC activities in gLTP, and indicate that ganglia from stressed rats may have expressed gLTP in vivo, which is known to precipitate hypertension in these animals. PMID:19038294

Alzoubi, K H; Alkadhi, K A

2009-02-01

306

Cerebellar abnormalities in Huntington's disease: a role in motor and psychiatric impairment?  

PubMed

The cerebellum has received limited attention in Huntington's disease (HD), despite signs of possible cerebellar dysfunction, including motor incoordination and impaired gait, which are currently attributed to basal ganglia atrophy and disrupted fronto-striatal circuits. This study is the first to investigate a potential contribution of macro- and microstructural cerebellar damage to clinical manifestations of HD. T1- and diffusion-weighted 3T magnetic resonance imaging (MRI) scans were obtained from 12 controls and 22 early-stage HD participants. Manual delineation and voxel-based morphometry were used to assess between-group differences in cerebellar volume, and diffusion metrics were compared between groups within the cerebellar gray and white matter. Associations between these imaging measures and clinical scores were examined within the HD group. Reduced paravermal volume was detected in HD compared with controls using voxel-based morphometry (P?abnormalities were detected in both cerebellar gray matter and white matter. Smaller cerebellar volumes, although not significantly reduced, were significantly associated with impaired gait and psychiatric morbidity and of borderline significance with pronate/supinate-hand task performance. Abnormal cerebellar diffusion was associated with increased total motor score, impaired saccade initiation, tandem walking, and timed finger tapping. In conclusion, atrophy of the paravermis, possibly encompassing the cerebellar nuclei, and microstructural abnormalities within the cerebellum may contribute to HD neuropathology. Aberrant cerebellar diffusion and reduced cerebellar volume together associate with impaired motor function and increased psychiatric symptoms in stage I HD, potentially implicating the cerebellum more centrally in HD presentation than previously recognized. PMID:25123926

Rees, Elin M; Farmer, Ruth; Cole, James H; Haider, Salman; Durr, Alexandra; Landwehrmeyer, Bernhard; Scahill, Rachael I; Tabrizi, Sarah J; Hobbs, Nicola Z

2014-11-01

307

A Cross-Sectional Study of Regional Brain Volume Abnormalities in Lesch-Nyhan Disease and its Variants  

PubMed Central

Background Lesch-Nyhan disease (LND) is a rare, X-linked, neurodevelopmental metabolic disorder that results from a near-complete lack of hypoxanthine phosphoribosyl-transferase enzyme activity. LND is characterized by hyperuricemia, motor neurological abnormalities, recurrent self-injury, and cognitive impairment, but its neural substrates remain poorly understood. Methods In this cross-sectional study, we measured gray matter abnormalities in 21 persons with LND, 17 with an attenuated variant of the phenotype (LNV), and 33 healthy controls using voxel-based morphometry. We conducted an analysis of covariance to identify group differences in regional gray matter volume (GMV), followed by six pair-wise post-hoc group comparisons. Findings Patients with LND showed 20% smaller intracranial volumes (17% gray and 26% white matter) than healthy adults. The largest differences were found in basal ganglia, frontotemporal, and limbic regions, with sparing of parieto-occipital regions. The gray matter volumes of LNV participants invariably fell between those of patients with classical LND and healthy controls. Compared to healthy adults, patients with LND showed additional GMV reductions in the temporal lobe and left lateralized structures, and patients with LNV showed additional reductions in lingual and precuneus regions with sparing of right frontal and temporal regions. LND participants showed reductions in the ventral striatum and prefrontal areas relative to LNV. Interpretation This study of brain morphology reveals regional abnormalities associated with known neurological and behavioral deficits in persons with LND. It also revealed that patients with LNV show milder gray matter abnormalities in many of the same brain regions and preservation of GMV in other regions which could provide important clues to the neural substrates of differences between thephenotypes. PMID:24383089

Schretlen, David J.; Varvaris, Mark; Ho, Tiffany E.; Vannorsdall, Tracy D.; Gordon, Barry; Harris, James C.; Jinnah, H. A.

2014-01-01

308

Severity of Dysfluency Correlates with Basal Ganglia Activity in Persistent Developmental Stuttering  

ERIC Educational Resources Information Center

Previous studies suggest that anatomical anomalies [Foundas, A. L., Bollich, A. M., Corey, D. M., Hurley, M., & Heilman, K. M. (2001). "Anomalous anatomy of speech-language areas in adults with persistent developmental stuttering." "Neurology," 57, 207-215; Foundas, A. L., Corey, D. M., Angeles, V., Bollich, A. M., Crabtree-Hartman, E., & Heilman,…

Giraud, Anne-Lise; Neumann, Katrin; Bachoud-Levi, Anne-Catherine; von Gudenberg, Alexander W.; Euler, Harald A.; Lanfermann, Heinrich; Preibisch, Christine

2008-01-01

309

[Bilateral lesions of the basal ganglia as a sign of chronic carbon monoxide intoxication  

Microsoft Academic Search

A 40-year-old, previously healthy man presented with a subacute coordination disorder and intermittent paraesthesias of the right arm that had begun several months before and had disappeared spontaneously within a few weeks. Neurological examination showed a mildly flattened nasolabial fold on the right side and subtle hypertonia of the right arm. A CT-scan of the brain revealed calcifications in the

C. A. Haaxma; J. J. J. van Eijk; A. M. van der Vilet; W. O. Renier; B. R. Bloem

2007-01-01

310

The effects of cues on neurons in the basal ganglia in Parkinson's disease  

E-print Network

Visual cues open a unique window to the understanding of Parkinson's disease (PD). These cues can temporarily but dramatically improve PD motor symptoms. Although details are unclear, cues are believed to suppress pathological ...

Brown, Emery N.

311

Hierarchical Learning Induces Two Simultaneous, But Separable, Prediction Errors in Human Basal Ganglia  

PubMed Central

Studies suggest that dopaminergic neurons report a unitary, global reward prediction error signal. However, learning in complex real-life tasks, in particular tasks that show hierarchical structure, requires multiple prediction errors that may coincide in time. We used functional neuroimaging to measure prediction error signals in humans performing such a hierarchical task involving simultaneous, uncorrelated prediction errors. Analysis of signals in a priori anatomical regions of interest in the ventral striatum and the ventral tegmental area indeed evidenced two simultaneous, but separable, prediction error signals corresponding to the two levels of hierarchy in the task. This result suggests that suitably designed tasks may reveal a more intricate pattern of firing in dopaminergic neurons. Moreover, the need for downstream separation of these signals implies possible limitations on the number of different task levels that we can learn about simultaneously. PMID:23536092

Tsai, Karin; Wallis, Jonathan; Botvinick, Matthew

2013-01-01

312

Basal Ganglia Volumes in Children With Attention-Deficit Hyperactivity Disorder  

Microsoft Academic Search

Previous research has demonstrated volume reduction of the left globus pallidus in children with the codiagnoses of Tourette syndrome and attention-deficit hyperactivity disorder (ADHD), in comparison with children who have Tourette syndrome alone and with normal controls. The purpose of this study was to determine whether children with ADHD alone also had volume reduction of the globus pallidus or other

Elizabeth H. Aylward; Allan L. Reiss; Mark J. Reader; Harvey S. Singer; Jan E. Brown; Martha B. Denckla

1996-01-01

313

Two forms of iron as an intrinsic contrast agent in the basal ganglia of PKAN patients.  

PubMed

Iron deposits in the human brain can be considered as intrinsic contrast agents for magnetic resonance imaging and are used as markers of neurodegeneration accompanied by brain-iron accumulation. We studied one of them - panthotenate-kinase associated neurodegeneration (PKAN) - by using relaxometry at 1.5, 3.0 and 7 T in a group of six patients; we also measured a group of five volunteers for comparison. Based on the magnetic field dependency of antiferromagnetic ferritin and maghemite iron oxide nanoparticle relaxivities, we derived a two-component model for the description of iron deposits in the globus pallidus of PKAN patients. According to this model, we estimated the iron content in PKAN patients as 391 µg/ml of antiferromagnetic iron (ferritin) and 1.1 µg/ml of ferrimagnetic iron, compared with 178 µg/ml of iron in ferritin found in controls. This two-component model explains the nonlinear shape of the relaxometric curves in in vivo measurements of the relaxation rates of PKAN patients and is supported by histological findings in the original reports on PKAN patients. PMID:22991317

Dezortova, Monika; Herynek, Vit; Krssak, Martin; Kronerwetter, Claudia; Trattnig, Siegfried; Hajek, Milan

2012-01-01

314

SYSTEMS NEUROSCIENCE Normal Basal gaNglia movemeNt-related activity  

E-print Network

). The motor BG domain is the most studied to date and will be the main focus of this review. The role and Izhar Bar-Gad1,2 * 1 The Leslie and Susan Gonda (Goldschmied) Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat-Gan, Israel 2 The Mina and Everard Goodman Faculty of Life Sciences, Bar

Bar-Gad, Izhar

315

A Rap Guanine Nucleotide Exchange Factor Enriched Highly in the Basal Ganglia  

Microsoft Academic Search

Ras proteins, key regulators of growth, differentiation, and malignant transformation, recently have been implicated in synaptic function and region-specific learning and memory functions in the brain. Rap proteins, members of the Ras small G protein superfamily, can inhibit Ras signaling through the Ras\\/Raf-1\\/mitogen-activated protein (MAP) kinase pathway or, through B-Raf, can activate MAP kinase. Rap and Ras proteins both can

Hiroaki Kawasaki; Gregory M. Springett; Shinichiro Toki; Juan J. Canales; Patricia Harlan; Justin P. Blumenstiel; Emy J. Chen; I. Amy Bany; Naoki Mochizuki; Amy Ashbacher; Michiyuki Matsuda; David E. Housman; Ann M. Graybiel

1998-01-01

316

Adenosine A2A Receptor in the Monkey Basal Ganglia: Ultrastructural Localization and Colocalization With  

E-print Network

) is a potential drug target for the treatment of Parkinson's disease and other neurological disorders. In rodents effects in parkinsonism. J. Comp. Neurol. 520:570­589, 2012. VC 2011 Wiley Periodicals, Inc. INDEXING TERMS: mGluR5; Parkinson's disease; primate; immunogold; globus pallidus; substantia nigra; putamen

Hall, Randy A

317

Congenital fibrosis of the extraocular muscles associated with cortical dysplasia and maldevelopment of the basal ganglia  

Microsoft Academic Search

BackgroundCongenital fibrosis of the extraocular muscles (CFEOM) is a rare condition that has been traditionally regarded as a primary eye muscle disease. Recent studies, however, suggest that CFEOM may be the result of a primary neuropathy with secondary myopathic changes.

Maree P Flaherty; Padraic Grattan-Smith; Adam Steinberg; Robyn Jamieson; Elizabeth C Engle

2001-01-01

318

Towards an executive without a homunculus: computational models of the prefrontal cortex\\/basal ganglia system  

Microsoft Academic Search

The prefrontal cortex (PFC) has long been thought to serve as an 'executive' that controls the selection of actions and cognitive functions more generally. However, the mechanistic basis of this executive function has not been clearly specified often amounting to a homunculus. This paper reviews recent attempts to deconstruct this homunculus by elucidating the precise computational and neural mechanisms underlying

Thomas E. Hazy; Michael J. Frank; Randall C. O'Reilly

2007-01-01

319

Basal Ganglia Calcification (BGC) in Down's Syndrome (DS)?Another Manifestation of Premature Aging  

Microsoft Academic Search

Not Available Bibtex entry for this abstract Preferred format for this abstract (see Preferences) Find Similar Abstracts: Use: Authors Title Return: Query Results Return items starting with number Query Form Database: Astronomy Physics arXiv e-prints

K. E. Wisniewski; J. H. French; J. F. Rosen; P. B. Kozlowski; M. Tenner; H. M. Wisniewski

1982-01-01

320

Interacting cortical and basal ganglia networks underlying finding and tapping to the musical beat.  

PubMed

Humans are able to find and tap to the beat of musical rhythms varying in complexity from children's songs to modern jazz. Musical beat has no one-to-one relationship with auditory features-it is an abstract perceptual representation that emerges from the interaction between sensory cues and higher-level cognitive organization. Previous investigations have examined the neural basis of beat processing but have not tested the core phenomenon of finding and tapping to the musical beat. To test this, we used fMRI and had musicians find and tap to the beat of rhythms that varied from metrically simple to metrically complex-thus from a strong to a weak beat. Unlike most previous studies, we measured beat tapping performance during scanning and controlled for possible effects of scanner noise on beat perception. Results showed that beat finding and tapping recruited largely overlapping brain regions, including the superior temporal gyrus (STG), premotor cortex, and ventrolateral PFC (VLPFC). Beat tapping activity in STG and VLPFC was correlated with both perception and performance, suggesting that they are important for retrieving, selecting, and maintaining the musical beat. In contrast BG activity was similar in all conditions and was not correlated with either perception or production, suggesting that it may be involved in detecting auditory temporal regularity or in associating auditory stimuli with a motor response. Importantly, functional connectivity analyses showed that these systems interact, indicating that more basic sensorimotor mechanisms instantiated in the BG work in tandem with higher-order cognitive mechanisms in PFC. PMID:23163420

Kung, Shu-Jen; Chen, Joyce L; Zatorre, Robert J; Penhune, Virginia B

2013-03-01

321

Disturbed GABAergic transmission in mutant Han-Wistar rats: further evidence for basal ganglia dysfunction.  

PubMed

A mutant strain of Wistar rats which carries an autosomal gene defect is characterized by a progressively developing hyperexcitability, tremor, olfactory and gustatory movements, bradykinesia, ataxia and a pathologically increased muscle tone of hindlimbs which can be measured by recording tonic activity in the electromyogram (EMG) of the gastrocnemius-soleus muscle. The activity of the GABA synthesizing enzyme glutamic acid decarboxylase (GAD) and the receptor binding of GABA as estimated by [3H]GABA binding to synaptic membranes were examined in olfactory bulbs, frontal cerebral cortex, corpus striatum, hippocampus, thalamus, hypothalamus, tectum, substantia nigra, medulla oblongata, cerebellum, and pons of mutant rats. Mutant rats exhibit a lower activity of GAD in synaptosomal fractions of olfactory bulbs and substantia nigra whereas GAD activity within the pons was increased. The changes in the activity of GAD were accompanied by alterations in [3H]GABA binding to synaptic membranes: GABA binding was significantly elevated in the olfactory bulbs and the substantia nigra, but it was markedly reduced in the pons. The functional importance of impaired nigral GABAergic transmission in mutant rats was demonstrated by the fact that intranigral injection of the GABA agonist muscimol reduced the tonic extension of the hindlimbs as indicated by reduced tonic EMG activity of the gastrocnemius-soleus muscle, while intranigral injection of the GABA antagonist bicuculline increased the disturbance. PMID:2998553

Schwarz, M; Löscher, W; Turski, L; Sontag, K H

1985-11-18

322

Basal Ganglia Disorders Associated with Imbalances in the Striatal Striosome and Matrix Compartments  

E-print Network

The striatum is composed principally of GABAergic, medium spiny striatal projection neurons (MSNs) that can be categorized based on their gene expression, electrophysiological profiles, and input–output circuits. Major ...

Crittenden, Jill R.

323

Changes in cortical, cerebellar and basal ganglia representation after comprehensive long term unilateral hand motor training.  

PubMed

We were interested in motor performance gain after unilateral hand motor training and associated changes of cerebral and cerebellar movement representation tested with functional magnetic resonance imaging (fMRI) before and after training. Therefore, we trained the left hand of strongly right-handed healthy participants with a comprehensive training (arm ability training, AAT) over two weeks. Motor performance was tested for the trained and non-trained hand before and after the training period. Functional imaging was performed for the trained and the non-trained hand separately and comprised force modulation with the fist, sequential finger movements and a fast writing task. After the training period the performance gain of tapping movements was comparable for both hand sides, whereas the motor performance for writing showed a higher training effect for the trained hand. fMRI showed a reduction of activation in supplementary motor, dorsolateral prefrontal cortex, parietal cortical areas and lateral cerebellar areas during sequential finger movements over time. During left hand writing lateral cerebellar hemisphere also showed reduced activation, while activation of the anterior cerebellar hemisphere was increased. An initially high anterior cerebellar activation magnitude was a predictive value for high training outcome of finger tapping and visual guided movements. During the force modulation task we found increased activation in the striate. Overall, a comprehensive long-term training of the less skillful hand in healthy participants resulted in relevant motor performance improvements, as well as an intermanual learning transfer differently pronounced for the type of movement tested. Whereas cortical motor area activation decreased over time, cerebellar anterior hemisphere and striatum activity seem to represent increasing resources after long-term motor training. PMID:25194587

Walz, A D; Doppl, K; Kaza, E; Roschka, S; Platz, T; Lotze, M

2014-09-01

324

Plasticity of basal ganglia neurocircuitries following perinatal asphyxia: effect of nicotinamide  

Microsoft Academic Search

The potential neuroprotection of nicotinamide on the consequences of perinatal asphyxia was investigated with triple organotypic\\u000a cultures. Perinatal asphyxia was induced in vivo by immersing foetuses-containing uterine horns removed from ready-to-deliver\\u000a rats into a water bath for 20 min. Sibling caesarean-delivered pups were used as controls. Three days later tissue from substantia\\u000a nigra, neostriatum and neocortex was dissected and placed on

Verena Klawitter; Paola Morales; Diego Bustamante; Sonia Gomez-Urquijo; Tomas Hökfelt; Mario Herrera-Marschitz

2007-01-01

325

Reduced basal ganglia ?-opioid receptor availability in trigeminal neuropathic pain: A pilot study  

PubMed Central

Background Although neuroimaging techniques have provided insights into the function of brain regions involved in Trigeminal Neuropathic Pain (TNP) in humans, there is little understanding of the molecular mechanisms affected during the course of this disorder. Understanding these processes is crucial to determine the systems involved in the development and persistence of TNP. Findings In this study, we examined the regional ?-opioid receptor (?OR) availability in vivo (non-displaceable binding potential BPND) of TNP patients with positron emission tomography (PET) using the ?OR selective radioligand [11C]carfentanil. Four TNP patients and eight gender and age-matched healthy controls were examined with PET. Patients with TNP showed reduced ?OR BPND in the left nucleus accumbens (NAc), an area known to be involved in pain modulation and reward/aversive behaviors. In addition, the ?OR BPND in the NAc was negatively correlated with the McGill sensory and total pain ratings in the TNP patients. Conclusions Our findings give preliminary evidence that the clinical pain in TNP patients can be related to alterations in the endogenous ?-opioid system, rather than only to the peripheral pathology. The decreased availability of ?ORs found in TNP patients, and its inverse relationship to clinical pain levels, provide insights into the central mechanisms related to this condition. The results also expand our understanding about the impact of chronic pain on the limbic system. PMID:23006894

2012-01-01

326

Cross-camera comparison of SPECT measurements of a 3-D anthropomorphic basal ganglia phantom  

Microsoft Academic Search

Purpose  SPECT examinations of neurotransmitter systems in the brain have to be comparable between centres to generate a comprehensive\\u000a data pool, e.g. for multicentre studies. Equipment-specific effects on quantitative evaluations and corresponding methods\\u000a for compensation, however, have been insufficiently examined. Previous studies have shown that quantitative results may vary\\u000a significantly according to the imaging equipment used, thereby affecting clinical interpretation of

Walter Koch; Perry E Radau; Wolfgang Münzing; Klaus Tatsch

2006-01-01

327

Preliminary observation of elevated levels of nanocrystalline iron oxide in the basal ganglia of neuroferritinopathy patients  

PubMed Central

Magnetometry analysis of brain tissue sub-samples from two neuroferritinopathy patients provides a preliminary indication that the amount of magnetic iron compounds associated with this rare disease is significantly larger than in age/sex-matched controls from the same region of the brain. The primary iron compounds contributing to the remanant magnetization of the tissue above 50 K and at body temperature, are both blocked and superparamagnetic (SPM) biogenic magnetite (Fe3O4) and/or maghemite (?-Fe2O3). The concentration of SPM magnetite is significant and appears to be proportional to the concentration of ferritin, which varies with progression of the disease. The mutated ferritin protein appears to be responsible for the presence of iron oxide nano-particules, which in turn could be responsible for extensive damage in the brain. PMID:17097860

Hautot, Dimitri; Pankhurst, Quentin A.; Morris, Chris M.; Curtis, Andrew; Burn, John; Dobson, Jon

2007-01-01

328

The role of the basal ganglia in learning and memory: Insight from Parkinson's Karin Foerde  

E-print Network

of the contents of memory and towards a focus on the specific computations carried out by distinct brain regions of memory are supported by different brain structures. A focus of research within this frame- work the organization of memory in the brain. It has led to major advances in understanding the role of the medial

Foerde, Karin

329

Basal Ganglia Activity in Pathological Gambling: A Fluorodeoxyglucose-Positron Emission Tomography Study  

Microsoft Academic Search

Background: Pathological gambling (PG) is a disorder classified as an impulse control disorder (DSM-IV) bridging impulsive, compulsive and addictive behaviors. The striatum and thalamus are supposed to be involved in the pathophysiological substrate of these behaviors. An increased relative glucose metabolic rate (rGMR) in patients with a diagnosis of PG had previously been reported in the medial and orbitofrontal cortex.

Stefano Pallanti; M. Mehmet Haznedar; Eric Hollander; Elizabeth M. LiCalzi; Silvia Bernardi; Randall Newmark; Monte S. Buchsbaum

2010-01-01

330

Unexpected interactions in the basal ganglia Bernardo L. Sabatini, M.D., Ph.D.  

E-print Network

AT- cells, release the inhibitory neurotransmitter GABA (-aminobutyric acid) and are inhibited by i an inhibitory output to thalamus, bidirectionally controlled from within the BG by direct (dSPNs) and indirect for neurons that release the neurotransmitter acetylcholine (ACh). Despite these differences, ChAT+ cells

Gruen, Sonja

331

Intercellular communication in sensory ganglia by purinergic receptors and gap junctions: implications for chronic pain.  

PubMed

Peripheral injury can cause abnormal activity in sensory neurons, which is a major factor in chronic pain. Recent work has shown that injury induces major changes not only in sensory neurons but also in the main type of glial cells in sensory ganglia-satellite glial cells (SGCs), and that interactions between sensory neurons and SGCs contribute to neuronal activity in pain models. The main functional changes observed in SGCs after injury are an increased gap junction-mediated coupling among these cells, and augmented sensitivity to ATP. There is evidence that the augmented gap junctions contribute to neuronal hyperexcitability in pain models, but the mechanism underlying this effect is not known. The changes in SGCs described above have been found following a wide range of injuries (both axotomy and inflammation) in somatic, orofacial and visceral regions, and therefore appear to be a general feature in chronic pain. We have found that in cultures of sensory ganglia calcium signals can spread from an SGC to neighboring cells by calcium waves, which are mediated by gap junctions and ATP acting on purinergic P2 receptors. A model is proposed to explain how augmented gap junctions and greater sensitivity to ATP can combine to produce enhanced calcium waves, which can lead to neuronal excitation. Thus this simple scheme can account for several major changes in sensory ganglia that are common to a great variety of pain models. PMID:22771859

Hanani, Menachem

2012-12-01

332

Abnormal P600 in heroin addicts with prolonged abstinence elicited during a working memory test.  

PubMed

The P600 component of event-related potentials, believed to be generated by anterior cingulate gyrus and basal ganglia, is considered as an index of aspects of second-pass parsing processes of information processing, having much in common with working memory (WM) systems. Moreover, dysfunction of these brain structures as well as WM deficits have been implicated in the pathophysiology of opioid addicts. The present study is focused on P600 elicited during a WM test in twenty heroin addicts with prolonged abstinence compared with an equal number of healthy controls. The results showed significantly prolonged latencies at right hemisphere, specifically at Fp2 abduction. Moreover, memory performance of patients did not differ from that of normal controls. These findings may indicate that abstinent heroin addicts manifest abnormal aspects of second-pass parsing processes as are reflected by the P600 latencies, elicited during a WM test. Additionally, the P600 might serve as a valuable investigative tool for a more comprehensive understanding of the neurobiological substrate of drug abuse. PMID:11409757

Papageorgiou, C; Liappas, I; Asvestas, P; Vasios, C; Matsopoulos, G K; Nikolaou, C; Nikita, K S; Uzunoglu, N; Rabavilas, A

2001-06-13

333

Neuromagnetic Evidence of Abnormal Movement-Related Beta Desynchronization in Parkinson's Disease  

PubMed Central

Parkinson's disease (PD) is a neurodegenerative disorder associated with debilitating motor, posture, and gait abnormalities. Human studies recording local field potentials within the subthalamic nucleus and scalp-based electroencephalography have shown pathological beta synchronization throughout the cortical–basal ganglia motor network in PD. Suppression of such pathological beta synchronization has been associated with improved motor function, which may explain the effectiveness of deep-brain stimulation. We used magnetoencephalography (MEG) to investigate neural population-level beta responses, and other oscillatory activity, during a motor task in unmedicated patients with PD and a matched group of healthy adults. MEG is a noninvasive neurophysiological technique that permits the recording of oscillatory activity during movement planning, execution, and termination phases. Each of these phases was independently examined using beamforming to distinguish the brain areas and movement phases, where pathological oscillations exist during motor control. Patients with PD exhibited significantly diminished beta desynchronization compared with controls prior to and during movement, which paralleled reduced alpha desynchronization. This study is the first to systematically investigate neural oscillatory responses in PD during distinct stages of motor control (e.g. planning, execution, and termination) and indicates that these patients have significant difficulty suppressing cortical beta synchronization during movement planning, which may contribute to their diminished movement capacities. PMID:23645717

Heinrichs-Graham, Elizabeth; Wilson, Tony W.; Santamaria, Pamela M.; Heithoff, Sheila K.; Torres-Russotto, Diego; Hutter-Saunders, Jessica A.L.; Estes, Katherine A.; Meza, Jane L.; Mosley, R. L.; Gendelman, Howard E.

2014-01-01

334

Neuromagnetic evidence of abnormal movement-related beta desynchronization in Parkinson's disease.  

PubMed

Parkinson's disease (PD) is a neurodegenerative disorder associated with debilitating motor, posture, and gait abnormalities. Human studies recording local field potentials within the subthalamic nucleus and scalp-based electroencephalography have shown pathological beta synchronization throughout the cortical-basal ganglia motor network in PD. Suppression of such pathological beta synchronization has been associated with improved motor function, which may explain the effectiveness of deep-brain stimulation. We used magnetoencephalography (MEG) to investigate neural population-level beta responses, and other oscillatory activity, during a motor task in unmedicated patients with PD and a matched group of healthy adults. MEG is a noninvasive neurophysiological technique that permits the recording of oscillatory activity during movement planning, execution, and termination phases. Each of these phases was independently examined using beamforming to distinguish the brain areas and movement phases, where pathological oscillations exist during motor control. Patients with PD exhibited significantly diminished beta desynchronization compared with controls prior to and during movement, which paralleled reduced alpha desynchronization. This study is the first to systematically investigate neural oscillatory responses in PD during distinct stages of motor control (e.g. planning, execution, and termination) and indicates that these patients have significant difficulty suppressing cortical beta synchronization during movement planning, which may contribute to their diminished movement capacities. PMID:23645717

Heinrichs-Graham, Elizabeth; Wilson, Tony W; Santamaria, Pamela M; Heithoff, Sheila K; Torres-Russotto, Diego; Hutter-Saunders, Jessica A L; Estes, Katherine A; Meza, Jane L; Mosley, R L; Gendelman, Howard E

2014-10-01

335

Mutations of the Human Homolog of Drosophila patched in the Nevoid Basal Cell Carcinoma Syndrome  

Microsoft Academic Search

The nevoid basal cell carcinoma syndrome (NBCCS) is an autosomal dominant disorder characterized by multiple basal cell carcinomas (BCCs), pits of the palms and soles, jaw keratocysts, a variety of other tumors, and developmental abnormalities. NBCCS maps to chromosome 9q22.3. Familial and sporadic BCCs display loss of heterozygosity in this region, consistent with the gene being a tumor suppressor. A

Heidi Hahn; Carol Wicking; Peter G Zaphiropoulos; Mae R Gailani; Susan Shanley; Abirami Chidambaram; Igor Vorechovsky; Erika Holmberg; Anne Birgitte Unden; Susan Gillies; Kylie Negus; Ian Smyth; Carolyn Pressman; David J Leffell; Bernard Gerrard; Alisa M Goldstein; Michael Dean; Rune Toftgard; Georgia Chenevix-Trench; Brandon Wainwright; Allen E Bale

1996-01-01

336

Ganglia of the Hand and Wrist: A Sonographic Analysis  

Microsoft Academic Search

OBJECTIVE. The purpose of this study was to analyze the sonographic appearance of a large series of pathologically proven ganglia. Ma TERIals and METHO ds . A computer search of sonography and pathology re- ports for hand and wrist ganglia was performed. All sonography reports and images were reviewed for ganglion size, location, presence of a neck, echogenicity, acoustic enhancement,

Sharlene A. Teefey; Nirvikar Dahiya; William D. Middleton; Richard H. Gelberman; Martin I. Boyer

337

Basal Septal Hypertrophy  

PubMed Central

A significant clinical problem is patients presenting with exercise-limiting dyspnoea, sometimes with associated chest pain, in the absence of detectable left ventricular (LV) systolic dysfunction, coronary artery disease, or lung disease. Often the patients are older, female, and have isolated basal septal hypertrophy (BSH), frequently on a background of mild hypertension. The topic of breathlessness in patients with clinical heart failure, but who have a normal ejection fraction (HFNEF) has attracted significant controversy over the past few years. This review aims to analyse the literature on BSH, identify the possible associations between BSH and HFNEF, and consequently explore possible pathophysiological mechanisms whereby clinical symptoms are experienced.

Kelshiker, Mihir A.; Mayet, Jamil; Unsworth, Beth; Okonko, Darlington O.

2013-01-01

338

Odontogenic keratocysts in Nevoid basal cell carcinoma syndrome: a case report  

PubMed Central

Nevoid basal cell carcinoma syndrome, a rare autosomal dominant disorder, comprises a number of abnormalities such as multiple nevoid basal cell carcinomas, skeletal abnormalities and multiple odontogenic keratocysts. Considering the rarity of this syndrome, we present a 12-year-old boy affected by this syndrome. He had multiple okcs, calcification of falx cerebri, bifid ribs, frontal bossing and hypertelorism. Characteristic cutaneous manifestation (nevoid basal cell carcinoma) was not present in this patient. The jaw cysts were treated with marsupialization then enucleation. The dental clinician may be the first to encounter and identify this syndrome, when the multiple cystlike radiolucencies are discovered on panoramic view. PMID:20111613

2009-01-01

339

Imaging neural crest cell dynamics during formation of dorsal root ganglia and sympathetic ganglia.  

PubMed

The neural crest is a migratory population of cells that produces many diverse structures within the embryo. Trunk neural crest cells give rise to such structures as the dorsal root ganglia (DRG) and sympathetic ganglia (SG), which form in a metameric pattern along the anterior-posterior axis of the embryo. While static analyses have provided invaluable information concerning the development of these structures, time-lapse imaging of neural crest cells navigating through their normal environment could potentially reveal previously unidentified cellular and molecular interactions integral to DRG and SG development. In this study, we follow fluorescently labeled trunk neural crest cells using a novel sagittal explant and time-lapse confocal microscopy. We show that along their dorsoventral migratory route, trunk neural crest cells are highly motile and interact extensively with neighboring cells and the environment, with many cells migrating in chain-like formations. Surprisingly, the segregated pattern of crest cell streams through the rostral somite is not maintained once these cells arrive alongside the dorsal aorta. Instead, neural crest cells disperse along the ventral outer border of the somite, interacting extensively with each other and their environment via dynamic extension and retraction of filopodia. Discrete sympathetic ganglia arise as a consequence of intermixing and selective reorganization of neural crest cells at the target site. The diverse cell migratory behaviors and active reorganization at the target suggest that cell-cell and cell-environment interactions are coordinated with dynamic molecular processes. PMID:15590743

Kasemeier-Kulesa, Jennifer C; Kulesa, Paul M; Lefcort, Frances

2005-01-01

340

Basal Cell Nevus Syndrome Showing Several Histologic Types of Basal Cell Carcinoma  

PubMed Central

Basal cell nevus syndrome (BCNS), or Gorlin Syndrome, is an autosomal dominant disorder, characterized by multiple developmental abnormalities and associated with germline mutations in the PTCH gene. Patients show multiple and early onset basal cell carcinomas (BCCs) in skin, odontogeniccysts in the jaw, pits on palms and soles, medulloblastoma, hypertelorism, and calcification of the falx cerebri. Clinical features of BCCs in these patients are indistinguishable from ordinary BCCs. However, some patients show variable histologic findings in subtypes of BCCs, and only one case associated with several histologic types of BCCs in the syndrome has been reported in Korea. We present a case of BCNS characterized by multiple BCCs, odontogenic keratocysts, multiple palmar pits, and calcified falx cerebri. Histopathologic findings of BCCs showed several patterns, which were nodular, superficial, and pigmented types. PMID:22028568

Go, Jae Wan; Kim, Shin Han; Yi, Sang Yeop

2011-01-01

341

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

PubMed Central

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. PMID:24860415

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

342

Metastasizing basal cell carcinoma.  

PubMed

Basal cell carcinoma (BCC) is the most common malignancy worldwide and is characterized by invasive growth and local tissue destruction. Cure rates for BCC exceed 90% with most treatment modalities. Metastasizing BCC (MBCC) is a rare complication of BCC with high morbidity and mortality rates. We report the case of a 66-year-old man with a large ulcerative lesion on the left side of the flank that was histopathologically diagnosed as a BCC. Clinical and imaging evaluations revealed substantial local invasion with regional lymph node, lung, liver, bone marrow, and bone metastasis. The patient died 7 months after the diagnosis was made. Potentially metastasizing BCCs cannot be definitely identified; thus early intervention with adequate treatment of all BCCs is advised. PMID:24343210

Di Lernia, Vito; Ricci, Cinzia; Zalaudek, Iris; Argenziano, Giuseppe

2013-11-01

343

Shape abnormalities of subcortical and ventricular structures in mild cognitive impairment and Alzheimer's disease: detecting, quantifying, and predicting.  

PubMed

This article assesses the feasibility of using shape information to detect and quantify the subcortical and ventricular structural changes in mild cognitive impairment (MCI) and Alzheimer's disease (AD) patients. We first demonstrate structural shape abnormalities in MCI and AD as compared with healthy controls (HC). Exploring the development to AD, we then divide the MCI participants into two subgroups based on longitudinal clinical information: (1) MCI patients who remained stable; (2) MCI patients who converted to AD over time. We focus on seven structures (amygdala, hippocampus, thalamus, caudate, putamen, globus pallidus, and lateral ventricles) in 754 MR scans (210 HC, 369 MCI of which 151 converted to AD over time, and 175 AD). The hippocampus and amygdala were further subsegmented based on high field 0.8 mm isotropic 7.0T scans for finer exploration. For MCI and AD, prominent ventricular expansions were detected and we found that these patients had strongest hippocampal atrophy occurring at CA1 and strongest amygdala atrophy at the basolateral complex. Mild atrophy in basal ganglia structures was also detected in MCI and AD. Stronger atrophy in the amygdala and hippocampus, and greater expansion in ventricles was observed in MCI converters, relative to those MCI who remained stable. Furthermore, we performed principal component analysis on a linear shape space of each structure. A subsequent linear discriminant analysis on the principal component values of hippocampus, amygdala, and ventricle leads to correct classification of 88% HC subjects and 86% AD subjects. PMID:24443091

Tang, Xiaoying; Holland, Dominic; Dale, Anders M; Younes, Laurent; Miller, Michael I

2014-08-01

344

Journal of Abnormal Psychology  

Microsoft Academic Search

This article is reprinted from the Journal of Abnormal Psychology, 1965, 70, 1. The Journal of Abnormal Psychology will give priority to articles on problems related to abnormal behavior, broadly defined. The Journal's interests thus include the following: (a) psychopathology--its development or acquisition, its treatment or remission, and its symptomatology and course; (b) normal processes in abnormal individuals; (c) pathological

Howard F. Hunt; William N. Thetford

1965-01-01

345

Alarin in cranial autonomic ganglia of human and rat.  

PubMed

Extrinsic and intrinsic sources of the autonomic nervous system contribute to choroidal innervation, thus being responsible for the control of choroidal blood flow, aqueous humor production or intraocular pressure. Neuropeptides are involved in this autonomic control, and amongst those, alarin has been recently introduced. While alarin is present in intrinsic choroidal neurons, it is not clear if these are the only source of neuronal alarin in the choroid. Therefore, we here screened for the presence of alarin in human cranial autonomic ganglia, and also in rat, a species lacking intrinsic choroidal innervation. Cranial autonomic ganglia (i.e., ciliary, CIL; pterygopalatine, PPG; superior cervical, SCG; trigeminal ganglion, TRI) of human and rat were prepared for immunohistochemistry against murine and human alarin, respectively. Additionally, double staining experiments for alarin and choline acetyltransferase (ChAT), tyrosine hydroxilase (TH), substance P (SP) were performed in human and rat ganglia for unequivocal identification of ganglia. For documentation, confocal laser scanning microscopy was used, while quantitative RT-PCR was applied to confirm immunohistochemical data and to detect alarin mRNA expression. In humans, alarin-like immunoreactivity (alarin-LI) was detected in intrinsic neurons and nerve fibers of the choroidal stroma, but was lacking in CIL, PPG, SCG and TRI. In rat, alarin-LI was detected in only a minority of cranial autonomic ganglia (CIL: 3.5%; PPG: 0.4%; SCG: 1.9%; TRI: 1%). qRT-PCR confirmed the low expression level of alarin mRNA in rat ganglia. Since alarin-LI was absent in human cranial autonomic ganglia, and only present in few neurons of rat cranial autonomic ganglia, we consider it of low impact in extrinsic ocular innervation in those species. Nevertheless, it seems important for intrinsic choroidal innervation in humans, where it could serve as intrinsic choroidal marker. PMID:25497346

Schrödl, Falk; Kaser-Eichberger, Alexandra; Trost, Andrea; Strohmaier, Clemens; Bogner, Barbara; Runge, Christian; Bruckner, Daniela; Krefft, Karolina; Kofler, Barbara; Brandtner, Herwig; Reitsamer, Herbert A

2015-02-01

346

Autonomic ganglia, acetylcholine receptor antibodies, and autoimmune ganglionopathy  

Microsoft Academic Search

Nicotinic acetylcholine receptors (AChR) are ligand-gated cation channels that are present throughout the nervous system. The ganglionic (?3-type) neuronal AChR mediates fast synaptic transmission in sympathetic, parasympathetic and enteric autonomic ganglia. Autonomic ganglia are an important site of neural integration and regulation of autonomic reflexes. Impaired cholinergic ganglionic synaptic transmission is one important cause of autonomic failure.Ganglionic AChR antibodies are

Steven Vernino; Steve Hopkins; Zhengbei Wang

2009-01-01

347

CHAPTER SEVEN Were Basal Primates  

E-print Network

233 CHAPTER SEVEN Were Basal Primates Nocturnal? Evidence from Eye and Orbit Shape Callum F. Ross pattern, Charles-Dominique (1975: 86) suggested that the last common ancestor of primates "had an eye or a strepsirrhine eye. By the late 1970s, the issue of the activity pattern of basal primates was independently

348

Report Card on Basal Readers.  

ERIC Educational Resources Information Center

This report examines the nature of the modern basal reader, its economics, and use. First, the report provides a history showing how the confluence of business principles, positivistic science, and behavioral psychology led to the transformation of reading textbooks into basal readers. Next, the report examines objectives and subjective factors…

Goodman, Kenneth S.; And Others

349

Autonomic Ganglia: Target and Novel Therapeutic Tool  

PubMed Central

Nicotinic acetylcholine receptors (AChR) are ligand-gated cation channels that are present throughout the nervous system. The muscle AChR mediates transmission at the neuromuscular junction; antibodies against the muscle AChR are the cause of myasthenia gravis. The ganglionic (?3-type) neuronal AChR mediates fast synaptic transmission in sympathetic, parasympathetic, and enteric autonomic ganglia. Impaired cholinergic ganglionic synaptic transmission is one important cause of autonomic failure. Pharmacological enhancement of ganglionic synaptic transmission may be a novel way to improve autonomic function. Ganglionic AChR antibodies are found in patients with autoimmune autonomic ganglionopathy (AAG). Patients with AAG typically present with rapid onset of severe autonomic failure. Major clinical features include orthostatic hypotension, gastrointestinal dysmotility, anhidrosis, bladder dysfunction, and sicca symptoms. Impaired pupillary light reflex is often seen. Like myasthenia, AAG is an antibody-mediated neurological disorder. The disease can be reproduced in experimental animals by active immunization or passive antibody transfer. Patient may improve with plasma exchange treatment or other immunomodulatory treatment. Antibodies from patients with AAG inhibit ganglionic AChR currents. Other phenotypes of AAG are now recognized based on the results of antibody testing. These other presentations are generally associated with lower levels of ganglionic AChR antibodies. A chronic progressive form of AAG may resemble pure autonomic failure. Milder forms of dysautonomia, such as postural tachycardia syndrome, are associated with ganglionic AChR in 10–15% of cases. Since ganglionic synaptic transmission is a common pathway for all autonomic traffic, enhancement of autonomic function through inhibition of acetylcholinesterase is a potential specific therapeutic strategy for autonomic disorders. Increasing the strength of ganglionic transmission can ameliorate neurogenic orthostatic hypotension without aggravating supine hypertension. Recent evidence also suggests a potential role for acetylcholinesterase inhibitors in the treatment of postural tachycardia syndrome. PMID:18474849

Vernino, Steven; Sandroni, Paola; Singer, Wolfgang; Low, Phillip A.

2009-01-01

350

Polar basal melting on Mars  

NASA Astrophysics Data System (ADS)

The potential importance of basal melting on Mars is illustrated through the discussion of four examples: (1) the origin of the major polar reentrants, (2) the removal and storage of an ancient Martian ice sheet, (3) the mass balance of the polar terrains, and (4) the possibility of basal melting at temperate latitudes. This analysis suggests that the process of basal melting may play a key role in understanding the evolution of the Martian polar terrains and the long-term climatic behavior of water on Mars.

Clifford, S. M.

1987-08-01

351

Abnormal Head Position  

MedlinePLUS

... cause. Can a longstanding head turn lead to any permanent problems? Yes, a significant abnormal head posture could cause permanent ... occipitocervical synostosis and unilateral hearing loss. Are there any ... postures? Yes. Abnormal head postures can usually be improved depending ...

352

Corticobasal degeneration: widespread argentophilic threads and glia in addition to neurofibrillary tangles. Similarities of cytoskeletal abnormalities in corticobasal degeneration and progressive supranuclear palsy  

Microsoft Academic Search

A 57-year-old man had exhibited cortical sensory disturbance, rigidity, spasticity, dementia, alien hand, grasp reflex, supranuclear ophthalmoplegia, pseudobulbar palsy, and neck dystonia for 4 years. Histological examination of autopsied specimens revealed neuronal loss in the cerebral cortex, with ballooned neurons, subthalamic nucleus, substantia nigra, basal ganglia, midbrain tegmentum, and the thalamus. There were neurofibrillary tangles in the subthalamic nucleus and

Tatsuya Takahashi; Naoji Amano; Tokiji Hanihara; Hideki Nagatomo; Saburo Yagishita; Yoji Itoh; Keiko Yamaoka; Hiroyuki Toda; Tatsuji Tanabe

1996-01-01

353

Neurodevelopment. Parasympathetic ganglia derive from Schwann cell precursors.  

PubMed

Neural crest cells migrate extensively and give rise to most of the peripheral nervous system, including sympathetic, parasympathetic, enteric, and dorsal root ganglia. We studied how parasympathetic ganglia form close to visceral organs and what their precursors are. We find that many cranial nerve-associated crest cells coexpress the pan-autonomic determinant Paired-like homeodomain 2b (Phox2b) together with markers of Schwann cell precursors. Some give rise to Schwann cells after down-regulation of PHOX2b. Others form parasympathetic ganglia after being guided to the site of ganglion formation by the nerves that carry preganglionic fibers, a parsimonious way of wiring the pathway. Thus, cranial Schwann cell precursors are the source of parasympathetic neurons during normal development. PMID:24925912

Espinosa-Medina, I; Outin, E; Picard, C A; Chettouh, Z; Dymecki, S; Consalez, G G; Coppola, E; Brunet, J-F

2014-07-01

354

CYTOLOGICAL STUDIES OF ORGANOTYPIC CULTURES OF RAT DORSAL ROOT GANGLIA FOLLOWING X-IRRADIATION IN VITRO  

PubMed Central

Long-term organotypic cultures of rat dorsal root ganglia were exposed to a single 40 kR dose of 184 kvp X-rays and studied in the living and fixed states by light or electron microscopy at 1–14 day intervals thereafter. Within the first 4 days following irradiation, over 30% of the neurons display chromatolytic reactions (eccentric nuclei, peripheral dispersal of Nissl substance, central granular zone) as well as abnormal nucleolar changes and dissociation of ribosomes from endoplasmic reticulum cisternae. Some satellite cells undergo retraction or acute degeneration, leaving only basement membrane to cover the neuron in these areas. 8 days after irradiation, neurons also exhibit (a) areas in which ribosomes are substantially reduced, (b) regions of cytoplasmic sequestration, (c) extensive vacuolization of granular endoplasmic reticulum and Golgi complex, and (d) diversely altered mitochondria (including the presence of ribosome-like particles or association with abnormal glycogen and lipid deposits). Nucleolar components become altered or reoriented and may form abnormal projections and ringlike configurations. Sizeable areas of the neuronal soma are now denuded of satellite cells; underlying these areas, nerve processes are found abnormally invaginated into the neuronal cytoplasm. By the 14th day following irradiation, most neurons display marked degenerative changes including extensive regions of ribosome depletion, sequestration, vacuolization, autolysis, and, in some areas, swirls of filaments, myelin figures, and heterogeneous dense bodies. These observations demonstrate that X-irradiation produces profound cytopathological changes in nervous tissue isolated from the host and that many of these changes resemble the effects of radiation on nervous tissue in vivo. PMID:10976234

Masurovsky, Edmund B.; Bunge, Mary Bartlett; Bunge, Richard P.

1967-01-01

355

Non-visual functions of crustacean eyestalk ganglia  

Microsoft Academic Search

Summary Ablation experiments demonstrated that in several crustacean groups, the proximal eyestalk ganglia are important in a variety of behavior patterns:1.Chemical elicitation of feeding via the antennules is altered in lobsters, hermit crabs, and some brachyuran crabs by bilateral eyestalk ablation; the ablation of one antennule and the contralateral eyestalk is effective in lobsters and hermit crabs;2.increased chewing of inedible

Brian A. Hazlett

1971-01-01

356

Evidence for Glutamate as a Neuroglial Transmitter within Sensory Ganglia  

PubMed Central

This study examines key elements of glutamatergic transmission within sensory ganglia of the rat. We show that the soma of primary sensory neurons release glutamate when depolarized. Using acute dissociated mixed neuronal/glia cultures of dorsal root ganglia (DRG) or trigeminal ganglia and a colorimetric assay, we show that when glutamate uptake by satellite glial cells (SGCs) is inhibited, KCl stimulation leads to simultaneous increase of glutamate in the culture medium. With calcium imaging we see that the soma of primary sensory neurons and SGCs respond to AMPA, NMDA, kainate and mGluR agonists, and selective antagonists block this response. Using whole cell patch-clamp technique, inward currents were recorded from small diameter (<30 µm) DRG neurons from intact DRGs (ex-vivo whole ganglion preparation) in response to local application of the above glutamate receptor agonists. Following a chronic constriction injury (CCI) of either the inferior orbital nerve or the sciatic nerve, glutamate expression increases in the trigeminal ganglia and DRG respectively. This increase occurs in neurons of all diameters and is present in the somata of neurons with injured axons as well as in somata of neighboring uninjured neurons. These data provides additional evidence that glutamate can be released within the sensory ganglion, and that the somata of primary sensory neurons as well as SGCs express functional glutamate receptors at their surface. These findings, together with our previous gene knockdown data, suggest that glutamatergic transmission within the ganglion could impact nociceptive threshold. PMID:23844184

Kung, Ling-Hsuan; Gong, Kerui; Adedoyin, Mary; Ng, Johnson; Bhargava, Aditi; Ohara, Peter T.; Jasmin, Luc

2013-01-01

357

Simian Varicella Virus DNA in Dorsal Root Ganglia  

Microsoft Academic Search

Clinical, pathological, immunological, and virological evidence suggests that simian varicella virus (SVV) infection of primates is the counterpart of varicella-zoster virus infection of humans. To determine whether these two viruses share similarities in their properties during latency, we analyzed ganglia and brain of an African green monkey experimentally infected with SVV for the presence of viral nucleic acid using the

Ravi Mahalingam; Diana Smith; Mary Wellish; William Wolf; Aud N. Dueland; Randall Cohrs; Kenneth Soike; Donald Gilden

1991-01-01

358

Autonomic ganglia, acetylcholine receptor antibodies, and autoimmune ganglionopathy  

PubMed Central

Nicotinic acetylcholine receptors (AChR) are ligand-gated cation channels that are present throughout the nervous system. The ganglionic (?3-type) neuronal AChR mediates fast synaptic transmission in sympathetic, parasympathetic and enteric autonomic ganglia. Autonomic ganglia are an important site of neural integration and regulation of autonomic reflexes. Impaired cholinergic ganglionic synaptic transmission is one important cause of autonomic failure. Ganglionic AChR antibodies are found in many patients with autoimmune autonomic ganglionopathy (AAG). These antibodies recognize the ?3 subunit of the ganglionic AChR, and thus do not bind non-specifically to other nicotinic AChR. Patients with high levels of ganglionic AChR antibodies typically present with rapid onset of severe autonomic failure, with orthostatic hypotension, gastrointestinal dysmotility, anhidrosis, bladder dysfunction and sicca symptoms. Impaired pupillary light reflex is often seen. Like myasthenia gravis, AAG is an antibody-mediated neurological disorder. Antibodies from patients with AAG inhibit ganglionic AChR currents and impair transmission in autonomic ganglia. An animal model of AAG in the rabbit recapitulates the important clinical features of the human disease and provides additional evidence that AAG is an antibody-mediated disorder caused by impairment of synaptic transmission in autonomic ganglia. PMID:18951069

Vernino, Steven; Hopkins, Steve; Wang, Zhengbei

2009-01-01

359

Autonomic ganglia, acetylcholine receptor antibodies, and autoimmune ganglionopathy.  

PubMed

Nicotinic acetylcholine receptors (AChR) are ligand-gated cation channels that are present throughout the nervous system. The ganglionic (alpha3-type) neuronal AChR mediates fast synaptic transmission in sympathetic, parasympathetic and enteric autonomic ganglia. Autonomic ganglia are an important site of neural integration and regulation of autonomic reflexes. Impaired cholinergic ganglionic synaptic transmission is one important cause of autonomic failure. Ganglionic AChR antibodies are found in many patients with autoimmune autonomic ganglionopathy (AAG). These antibodies recognize the alpha3 subunit of the ganglionic AChR, and thus do not bind non-specifically to other nicotinic AChR. Patients with high levels of ganglionic AChR antibodies typically present with rapid onset of severe autonomic failure, with orthostatic hypotension, gastrointestinal dysmotility, anhidrosis, bladder dysfunction and sicca symptoms. Impaired pupillary light reflex is often seen. Like myasthenia gravis, AAG is an antibody-mediated neurological disorder. Antibodies from patients with AAG inhibit ganglionic AChR currents and impair transmission in autonomic ganglia. An animal model of AAG in the rabbit recapitulates the important clinical features of the human disease and provides additional evidence that AAG is an antibody-mediated disorder caused by impairment of synaptic transmission in autonomic ganglia. PMID:18951069

Vernino, Steven; Hopkins, Steve; Wang, Zhengbei

2009-03-12

360

Structurally abnormal human autosomes  

SciTech Connect

Chapter 25, discusses structurally abnormal human autosomes. This discussion includes: structurally abnormal chromosomes, chromosomal polymorphisms, pericentric inversions, paracentric inversions, deletions or partial monosomies, cri du chat (cat cry) syndrome, ring chromosomes, insertions, duplication or pure partial trisomy and mosaicism. 71 refs., 8 figs.

NONE

1993-12-31

361

Aluminum-induced neurofilamentous changes in cultured rat dorsal root ganglia explants.  

PubMed

Intrathecal administration of aluminum (AI) salts to susceptible species causes prominent accumulations of neurofilaments (NFs) in neurons of the CNS. Involved nerve cells display abnormal phosphorylation of perikaryal NFs, impaired axonal transport of NFs, and reduced levels of mRNA for NF proteins. Further understanding of the pathogenesis of AI toxicity has been limited by difficulties inherent in the available in vivo systems. For this reason, we have developed a model to study the effects of AI on cultured sensory neurons. Explant cultures of rat dorsal root ganglia (DRG) were exposed to 1 mM aluminum lactate for 1 d, 3 d, or 7 d and then examined morphologically. Accumulations of NFs were noted as early as 1 d after exposure, and prominent masses of NFs were seen at 3 and 7 d. Northern analysis of mRNA extracted from the cultured ganglia showed that high, medium, and low molecular weight NF protein mRNA levels were markedly reduced compared to control values by 1 d of exposure. Class II beta-tubulin mRNA was also moderately decreased. Reversibility of toxicity was assessed by removing the aluminum lactate from the medium after a 3 d exposure and examining the cultures 1 week later. The perikaryal masses of NFs dispersed and the levels of mRNA coding for the NF proteins and class II beta-tubulin increased. The neurotoxic effects of AI on cultured DRG recapitulates the effects of intrathecal administration of AI on animals; this model produces similar changes in neuronal morphology with neurofilamentous masses and similar modifications of NF gene expression.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1578268

Gilbert, M R; Harding, B L; Hoffman, P N; Griffin, J W; Price, D L; Troncoso, J C

1992-05-01

362

Observation on the distribution of ganglia in the ganglionated plexus of guinea-pig gallbladder.  

PubMed

In order to investigate how the ganglia in ganglionated plexus were distributed throughout the overall region of the gallbladder, the gallbladder was dissected from guinea-pig and washed with Krebs solution via the cystic duct. This gallbladder was distended with 2 ml of the mixed solution of OsO4 and ZnI2 injected with a syringe via the cystic duct and the cystic duct was immediately tied with a thread. The gallbladder was placed in excess of the mixed solution for 7-10 hours. The gallbladder was longitudinally divided into two approximately equal parts and each was prepared for microscopic investigation. The one preparation was the ventral side of the gallbladder and the other preparation was its dorsal side. These preparations were viewed through a photomicroscope. The obtained results were as follows: 1. Ganglia which involved several nerve cells were observed. Ganglia and nerve bundles connecting the fellow ganglia formed an irregular network, that is, the so-called ganglionated plexus. These nerve bundles were connected with the perivascular nerves which ran parallel to and around blood vessels in several places of the wall of the gallbladder. 2. Ganglia were full of variety in size and shape. That is to say, the shape of ganglia is arranged in various patterns such as oval, spherical, triangular, square and so on. When the size of ganglia were shown by surface area of ganglia which were viewed within the sweep of photomicroscope, the size of ganglia were divided into three large groups, the small ganglia in the range of 1,400 microns2-3,500 microns 2, the large ganglia in the range of 3,500 microns2-10,000 microns2 and the extra-large ganglia in the range of 10,000 microns2-38,000 microns2. Per one gallbladder, 240 +/- 41 (n = 3) small ganglia, 263 +/- 28 (n = 3) large ganglia and 8 +/- 1 (n = 3) extra-large ganglia were found. And these ganglia were irregularly scattered all over the wall of gallbladder. Small ganglia were found more numerous than large ganglia in the cervical portion of the gallbladder. On the other hand, small ones were slightly fewer than large ganglia in the remainder portion of the gallbladder. 3. The ganglionated plexus contained 511 +/- 69 (n = 3) ganglia.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:3244212

Yoshida, M; Tsuruta, Y

1988-05-01

363

Morphological abnormalities among lampreys  

USGS Publications Warehouse

The experimental control of the sea lamprey (Petromyzon marinus) in the Great Lakes has required the collection of thousands of lampreys. Representatives of each life stage of the four species of the Lake Superior basin were examined for structural abnormalities. The most common aberration was the presence of additional tails. The accessory tails were always postanal and smaller than the normal tail. The point of origin varied; the extra tails occurred on dorsal, ventral, or lateral surfaces. Some of the extra tails were misshaped and curled, but others were normal in shape and pigment pattern. Other abnormalities in larval sea lampreys were malformed or twisted tails and bodies. The cause of the structural abnormalities is unknown. The presence of extra caudal fins could be genetically controlled, or be due to partial amputation or injury followed by abnormal regeneration. Few if any lampreys with structural abnormalities live to sexual maturity.

Manion, Patrick J.

1967-01-01

364

Cryptophthalmos syndrome with basal encephaloceles.  

PubMed

A 2,144-g white girl was born with absence of the right ear and eye, cleft lip and palate, two basal encephaloceles, tricuspid atresia, ventricualr and atrial septal defects, detransposition of the great vessels, right aortic arch, and aberrant right subclavian artery. Through an oval defect in the center of the sphenoid bone, soft tissue protruded into the right nasopharynx. The medial portions of the roof of both orbits and the cribriform plate were absent and soft tissue protruded through this bony defect. Basal tomography was required to demonstrate the encephaloceles, which should be suspected in any child with a median cleft syndrome, a flat broad nasal root, and hypertelorism. PMID:168776

Goldhammer, Y; Smith, J L

1975-07-01

365

Cooperation of the basal ganglia, cerebellum, sensory cerebrum and hippocampus: possible implications for cognition, consciousness, intelligence and creativity  

Microsoft Academic Search

It is suggested that the anatomical structures which mediate consciousness evolved as decisive embellishments to a (non-conscious) design strategy present even in the simplest unicellular organisms. Consciousness is thus not the pinnacle of a hierarchy whose base is the primitive reflex, because reflexes require a nervous system, which the single-celled creature does not possess. By postulating that consciousness is intimately

Rodney M. J. Cotterill

2001-01-01

366

Binding sites for 5-hydroxytryptamine-2 receptor agonists are predominantly located in striosomes in the human basal ganglia.  

PubMed

Previous autoradiographic studies have shown that serotonin 5-HT2 receptors are homogeneously distributed in the human striatum. While these studies were done using antagonist radioligands such as [3H]ketanserin, we describe here a heterogeneous distribution of 5-HT2 binding sites in the human striatum, using [3H]LSD and [125I]DOI as ligands. Beside their agonist properties, these compounds belong to the family of psychedelic drugs. The localization of their binding sites in the dorsal striatum is very similar to that of striosomes, as visualized by acetylcholinesterase histochemistry or [3H]flunitrazepam labelling. This heterogeneous distribution seems to be a peculiarity of the human and guinea-pig brain, for it is not found in the monkey, cat, pig, and cow. In the rat striatum, a weak patchniness was seen, but corresponded to 5-HT1C binding sites. The density of [125I]DOI binding sites over striosomes presents large variations, which can neither be correlated with parameters such as age, gender and post-mortem delay nor with the effects of neurodegenerative disorders, with the exception of Huntington's disease, at late stages of the disease. The drug binding profile of [125I]DOI binding sites in the striosomes is identical to that of matrix binding sites. It is also fully comparable to the pharmacological profile of cortical 5-HT2 sites reported using [3H]ketanserin as a radioligand, with the exception of the higher affinity displayed by agonists for [125I]DOI binding sites. Interestingly, biphasic displacement curves yield a better fit for spiperone, cinanserin and ketanserin competitions. This biphasic profile can probably neither be accounted for by the presence of 5-HT1C sites nor by the existence of multiple affinity states. Taken together, these data suggest that a heterogeneous population of 5-HT2 receptors is present on the cell bodies or dendrites of striosomal neurons. These receptors provide an additional anatomical substrate to explain the psychedelic action of indoleamine (LSD) and phenylethylamine (DOI, DOM) drugs. PMID:7968358

Waeber, C; Palacios, J M

1994-07-01

367

Late onset familial dystonia: could mitochondrial deficits induce a diffuse lesioning process of the whole basal ganglia system?  

Microsoft Academic Search

BACKGROUNDStriatal necrosis has been related to various clinical syndromes, with acute or chronic progression, and juvenile or late occurrence, but the most common type is Leigh’s encephalopathy.METHODSBetween 1967 and 1995, six out of seven related patients with chronic familial dystonia were examined. MRIs were performed in four, between 1992-1994. The seven members, affected over three generations, were the father, three

D Caparros-Lefebvre; A Destée; H Petit

1997-01-01

368

The Contribution of NMDAR Signaling in the Cortico-Basal Ganglia Reward Network to Appetitive Pavlovian Learning  

PubMed Central

N-methyl-D-aspartate type glutamate receptors (NMDARs) contribute to phasic transmission and synaptic plasticity and are thought to be important for learning. To better understand where NMDAR signalling is necessary for learning, we combined viral-genetic strategies with genetic mouse models to investigate the contribution of NMDARs in the dopamine system to appetitive Pavlovian conditioning. NMDAR signaling in dopamine neurons was not required for Pavlovian conditioning; however, NMDARs in D1 dopamine receptor (D1R)-expressing medium spiny neurons (MSNs) which receive input from dopamine neurons were critical for this type of learning. NMDAR signaling was also required in brain regions that project to dopamine neurons, since removing NMDARs from afferent neurons to the ventral tegmental area (VTA) also prevented learning. This effect was likely due to loss of NMDAR signaling in the neurons of the prefrontal cortex (PFC), as learning could be restored in these animals by rescuing NMDAR expression in the PFC. Moreover, removing NMDARs exclusively from the PFC also prevented learning. Our findings suggest that NMDARs in neurons that project to and receive projections from the VTA are necessary for Pavlovian conditioning and specifically implicate the PFC and D1R-expressing MSNs in associative learning. PMID:21813695

Parker, Jones G; Beutler, Lisa R; Palmiter, Richard D

2011-01-01

369

The Aicardi-Goutières syndrome (familial, early onset encephalopathy with calcifications of the basal ganglia and chronic cerebrospinal fluid lymphocytosis).  

PubMed Central

Aicardi-Goutières syndrome (Mendelian inheritance in man Catalog No *225750) is an autosomal recessive encephalopathy which causes developmental arrest, intracerebral calcification, and white matter disease in the presence of chronic cerebrospinal fluid lymphocytosis, and a raised level of cerebrospinal fluid interferon-alpha (IFN-alpha). Diagnosis requires the presence of progressive encephalopathy with onset shortly after birth, and characteristic clinical neurological and neuroimaging signs together with chronic CSF lymphocytosis. The syndrome has superficial resemblance to the neurological sequelae of congenital infection, thus a rigorous search for microbiological and serological evidence of embryopathic infections should be carried out in each case. Images PMID:8592332

Tolmie, J L; Shillito, P; Hughes-Benzie, R; Stephenson, J B

1995-01-01

370

The basal ganglia and inhibitory mechanisms in response selection: evidence from subliminal priming of motor responses in Parkinson's disease  

Microsoft Academic Search

Summary Subliminal response priming was used to investigate inhibitory control processes relevant to response selec- tion impairments in Parkinson's disease. Using a back- ward masking technique, covert activation of left- or right-hand responses was induced without subjects con- sciously perceiving the stimuli (right- or left-pointing arrows). The masked priming stimuli were followed by visible arrow stimuli, instructing for a left-

Ellen Seiss; Peter Praamstra

2004-01-01

371

Chemoarchitecture and afferent connections of the "olfactostriatum": a specialized vomeronasal structure within the basal ganglia of snakes.  

PubMed

The olfactostriatum, a portion of the striatal complex of snakes, is the major tertiary vomeronasal structure in the ophidian brain, receiving substantial afferents from the nucleus sphericus, the primary target of accessory olfactory bulb efferents. In the present study, we have characterized the olfactostriatum of garter snakes (Thamnophis sirtalis) on the basis of chemoarchitecture (distribution of serotonin, neuropeptide Y and tyrosine hydroxylase) and hodology (afferent connections). The olfactostriatum is densely immunoreactive for serotonin and neuropeptide Y and shows moderate-to-weak immunoreactivity for tyrosine hydroxylase. In addition to afferents from the nucleus sphericus, the olfactostriatum receives inputs from the dorsal and lateral cortices, nucleus of the accessory olfactory tract, external and dorsolateral amygdalae, dorsomedial thalamic nucleus, ventral tegmental area and raphe nuclei. Double labeling experiments demonstrated that the distribution of serotonin and neuropeptide Y in this area almost completely overlaps the terminal field of projections from the nucleus sphericus. Also, serotonergic and dopaminergic innervation of the olfactostriatum likely arise, respectively, from the raphe nuclei and the ventral tegmental area, whereas local circuit neurons originate the neuropeptide Y immunoreactivity. These results indicate that the olfactostriatum of snakes could be a portion of the nucleus accumbens, with features characteristic of the accumbens shell, devoted to processing vomeronasal information. Comparative data suggest that a similar structure is present in the ventral striatum of amphibians and mammals. PMID:15589701

Martinez-Marcos, Alino; Ubeda-Bañon, Isabel; Lanuza, Enrique; Halpern, Mimi

2005-01-01

372

Oculomotor learning revisited: a model of reinforcement learning in the basal ganglia incorporating an efference copy of motor actions  

E-print Network

In its simplest formulation, reinforcement learning is based on the idea that if an action taken in a particular context is followed by a favorable outcome, then, in the same context, the tendency to produce that action ...

Fee, Michale S.

373

Facial nerve parasympathetic preganglionic afferents to the accessory otic ganglia by way of the chorda tympani nerve in the cat  

Microsoft Academic Search

The distribution of accessory otic ganglia and connections between the ganglia and the chorda tympani nerve were investigated\\u000a in the cat in order to determine the parasympathetic preganglionic facial nerve afferents to the otic ganglia using whole\\u000a mount acetylthiocholinesterase (WATChE) histochemistry. The otic ganglia consist of a sigle main prominent ganglion and many\\u000a small accessory ganglia lying on a plexus

Satoshi Kuchiiwa; T. Kuchiiwa; Satoru Nonaka; Shiro Nakagawa

1998-01-01

374

"Jeopardy" in Abnormal Psychology.  

ERIC Educational Resources Information Center

Describes the use of the board game, Jeopardy, in a college level abnormal psychology course. Finds increased student interaction and improved application of information. Reports generally favorable student evaluation of the technique. (CFR)

Keutzer, Carolin S.

1993-01-01

375

Abnormal Uterine Bleeding  

MedlinePLUS

... as cancer of the uterus, cervix, or vagina • Polycystic ovary syndrome How is abnormal bleeding diagnosed? Your health care ... before the fetus can survive outside the uterus. Polycystic Ovary Syndrome: A condition characterized by two of the following ...

376

Tooth - abnormal colors  

MedlinePLUS

... age when teeth are forming Poor oral care Porphyria Severe neonatal jaundice Too much fluoride from environmental ... abnormal coloration began Foods you have been eating Medications you are taking Personal and family health history ...

377

The ganglia distributed monitoring system: design, implementation, and experience  

Microsoft Academic Search

Ganglia is a scalable distributed monitoring system for high performance computing sys- tems such as clusters and Grids. It is based on a hierarchical design targeted at federations of clusters. It relies on a multicast-based listen\\/announce protocol to monitor state within clus- ters and uses a tree of point-to-point connections amongst representative cluster nodes to fed- erate clusters and aggregate

Matthew L. Massie; Brent N. Chun; David E. Culler

2004-01-01

378

The Human Airway Epithelial Basal Cell Transcriptome  

PubMed Central

Background The human airway epithelium consists of 4 major cell types: ciliated, secretory, columnar and basal cells. During natural turnover and in response to injury, the airway basal cells function as stem/progenitor cells for the other airway cell types. The objective of this study is to better understand human airway epithelial basal cell biology by defining the gene expression signature of this cell population. Methodology/Principal Findings Bronchial brushing was used to obtain airway epithelium from healthy nonsmokers. Microarrays were used to assess the transcriptome of basal cells purified from the airway epithelium in comparison to the transcriptome of the differentiated airway epithelium. This analysis identified the “human airway basal cell signature” as 1,161 unique genes with >5-fold higher expression level in basal cells compared to differentiated epithelium. The basal cell signature was suppressed when the basal cells differentiated into a ciliated airway epithelium in vitro. The basal cell signature displayed overlap with genes expressed in basal-like cells from other human tissues and with that of murine airway basal cells. Consistent with self-modulation as well as signaling to other airway cell types, the human airway basal cell signature was characterized by genes encoding extracellular matrix components, growth factors and growth factor receptors, including genes related to the EGF and VEGF pathways. Interestingly, while the basal cell signature overlaps that of basal-like cells of other organs, the human airway basal cell signature has features not previously associated with this cell type, including a unique pattern of genes encoding extracellular matrix components, G protein-coupled receptors, neuroactive ligands and receptors, and ion channels. Conclusion/Significance The human airway epithelial basal cell signature identified in the present study provides novel insights into the molecular phenotype and biology of the stem/progenitor cells of the human airway epithelium. PMID:21572528

Wang, Rui; Zwick, Rachel K.; Ferris, Barbara; Witover, Bradley; Salit, Jacqueline; Crystal, Ronald G.

2011-01-01

379

Demonstration of myenteric plexus abnormalities in genetic diseases by a microdissection technique: preliminary studies.  

PubMed

Eighty-eight specimens of esophagus, small intestine, or colon from 45 patients, predominantly infants and children, with 30 different genetic diseases were analyzed by a microdissection technique for the following abnormalities of the Auerbach (myenteric) plexus: (1) abnormality of the pattern of the nervous network of the plexus, (2) abnormal fraction of neural tissue in the plane of the plexus, (3) abnormal size or appearance of the cytoplasm of the neurons of the plexus, and (4) abnormal number of neurons in the ganglia of the plexus. Seven of 8 specimens of esophagus from patients with neuronal storage diseases (infantile Niemann-Pick disease, Jansky-Bielschowsky disease, etc.) showed an increased fraction of neural tissue in the plane of the plexus, whereas 2 of 3 patients with Cockayne syndrome showed a reduced fraction, with abnormally slender interganglionic fibers. The fraction of neural tissue in the plane of the plexus was also abnormal at one or more levels in patients with adrenoleukodystrophy, ataxia telangiectasia, Krabbe disease, and juvenile metachromatic leukodystrophy. Abnormality of neuron size and cytology was seen in several neuronal lipidoses, including Jansky-Bielschowsky and Sandhoff diseases and juvenile GM2 gangliosidosis, with the most striking neuronal enlargement noted in infantile Niemann-Pick disease. Abnormalities of plexus mass or pattern, as well as those of neuronal cytoplasm and neuron number, offer improved insight into possible mechanisms producing gastrointestinal tract dysfunction (swallowing difficulty, gastroesophageal reflux, constipation, etc) in patients with genetic disorders. PMID:3130868

Galvis, D A; Nakazato, Y; Wells, T R; Landing, B H

1987-01-01

380

EmergencyEmergency and Abnormal Situationsand Abnormal Situations  

E-print Network

SituationsAbnormal Situations Neil Johnston Aerospace Psychology Research Group Trinity College DublinEmergencyEmergency and Abnormal Situationsand Abnormal Situations in Aviation Symposiumin Aviation Symposium Santa Clara, June 2003 #12;Responding toResponding to Emergencies andEmergencies and Abnormal

381

Motoneuron development influences dorsal root ganglia survival and Schwann cell development in a vertebrate model of spinal muscular atrophy.  

PubMed

Low levels of the survival motor neuron protein (SMN) cause the disease spinal muscular atrophy. A primary characteristic of this disease is motoneuron dysfunction and paralysis. Understanding why motoneurons are affected by low levels of SMN will lend insight into this disease and to motoneuron biology in general. Motoneurons in zebrafish smn mutants develop abnormally; however, it is unclear where Smn is needed for motoneuron development since it is a ubiquitously expressed protein. We have addressed this issue by expressing human SMN in motoneurons in zebrafish maternal-zygotic (mz) smn mutants. First, we demonstrate that SMN is present in axons, but only during the period of robust motor axon outgrowth. We also conclusively demonstrate that SMN acts cell autonomously in motoneurons for proper motoneuron development. This includes the formation of both axonal and dendritic branches. Analysis of the peripheral nervous system revealed that Schwann cells and dorsal root ganglia (DRG) neurons developed abnormally in mz-smn mutants. Schwann cells did not wrap axons tightly and had expanded nodes of Ranvier. The majority of DRG neurons had abnormally short peripheral axons and later many of them failed to divide and died. Expressing SMN just in motoneurons rescued both of these cell types showing that their failure to develop was secondary to the developmental defects in motoneurons. Driving SMN just in motoneurons did not increase survival of the animal, suggesting that SMN is needed for motoneuron development and motor circuitry, but that SMN in other cells types factors into survival. PMID:25180019

Hao, Le Thi; Duy, Phan Q; Jontes, James D; Beattie, Christine E

2015-01-15

382

Evaluation of Cytotoxic Responses Caused by Selected Organophosphorus Esters in Chick Sympathetic Ganglia Cultures  

PubMed Central

Ten day old chick sympathetic ganglia cultured in a microslide assembly were treated with a selected group of organophosphate pesticides to evaluate their cytotoxicity ranges, and the usefulness of such a model for screening pesticides. Examination by phase contrast and light microscopy for chemically-induced morphological alteration of nerve fibers, glial cells and neurons provided the criteria for quantitation and assessment of the toxic effects. Concentrations that produced half-maximal effects ranged from 1 × 10-6M (severely toxic) for methylparathian, diazinon, paraoxon, mevinphos, diisopropylfluorophosphate, tri-o-tolyl phosphate and its mixed isomers to a 1 × 10-3M (intermediate) for malathion, leptophos, coumaphos, mono- and dicrotophos. Some or no effects were evident at 1 × 102-M for O'ethyl-O-p-nitrophenyl phenyl phosphonothioate, tri-m-tolylphosphate, chlorpyriphos and triphenyl phosphate. In all instances, nerve fibers were more sensitive than neurons or glial cells to insecticides. All cellular growth was inhibited at 1 × 10-2M (except triphenyl phosphate). Below 1 x 10-7M, no inhibitory effects were evident. The secondary abnormalities included decreased cellular migration, diffuse cellular growth pattern, increased vacuolization, nerve fiber swelling and cellular degeneration. The cytotoxic effects of these chemicals do not appear to be related to in vivo toxicity or cholinesterase inhibition potential. ImagesFig. 1.Fig. 2.Fig. 3.Fig. 4.Fig. 5.Fig. 6. PMID:565668

Obersteiner, E. J.; Sharma, R. P.

1978-01-01

383

Feline mammary basal-like adenocarcinomas: a potential model for human triple-negative breast cancer (TNBC) with basal-like subtype  

PubMed Central

Background Breast cancer is one of the leading causes of cancer deaths. Triple-negative breast cancer (TNBC), an immunophenotype defined by the absence of immunolabeling for estrogen receptor (ER), progesterone receptor (PR) and HER2 protein, has a highly aggressive behavior. A subpopulation of TNBCs exhibit a basal-like morphology with immunohistochemical positivity for cytokeratins 5/6 (CK5/6) and/or epidermal growth factor receptor (EGFR), and have a high incidence of BRCA (breast cancer susceptibility) mutations. Feline mammary adenocarcinomas (FMAs) are highly malignant and share a similar basal-like subtype. The purpose of this study was to classify FMAs according to the current human classification of breast cancer that includes evaluation of ER, PR and HER2 status and expression of basal CK 5/6 and EGFR. Furthermore, we selected triple negative, basal-like FMAs to screen for BRCA mutations similar to those described in human TNBC. Methods Twenty four FMAs were classified according to the current human histologic breast cancer classification including immunohistochemistry (IHC) for ER, PR HER2, CK5/6 and EGFR. Genetic alteration and loss of heterozygosity of BRCA1 and BRCA2 genes were analyzed in triple negative, basal-like FMAs. Results IHC for ER, PR and HER2 identified 14 of the 24 (58%) FMAs as a triple negative. Furthermore, 11of these 14 (79%) triple negative FMAs had a basal-like subtype. However, no genetic abnormalities were detected in BRCA1 and BRCA2 by direct sequencing and loss of heterozygosity analysis. Conclusion FMAs are highly aggressive neoplasms that are commonly triple negative and exhibit a basal-like morphology. This is similar to human TNBC that are also commonly classified as a basal-like subtype. While sequencing of a select number of triple negative, basal-like FMAs and testing for loss of heterozygosity of BRCA1 and BRCA2 did not identify mutations similar to those described in human TNBC, further in-depth evaluation is required to elucidate a potential role of BRCA in the tumorigenesis of triple negative, basal-like FMAs. The strong similarities in clinical behavior, morphology and IHC phenotype suggest that triple negative, basal-like FMAs may be a suitable spontaneous animal model for studying novel therapeutic approaches against human basal-like TNBC. PMID:24004841

2013-01-01

384

Abnormal Psychology Psychology 280  

E-print Network

1 Abnormal Psychology Psychology 280 1st Summer Session 2013 May 13June 27, 2013 Tuesday" Kalibatseva, M.A. Office: 127B Psychology Building Email: kalibats@msu.edu Phone Psychology PhD program at Michigan State University. I completed my bachelor's dual degree in psychology

Liu, Taosheng

385

Cytotoxic responses of selected insecticides in chick ganglia cultures.  

PubMed Central

Various agricultural chemicals, e.g. pesticides, are known to cause different toxic effects in man and animals. Some of these produce responses involving the nervous tissue. Total of 52 such chemicals, representing organophosphates, carbamates and other miscellaneous insecticides were evaluated to determine their relative cytotoxic effects in avian dorsal root ganglia cultures. Many of these chemicals caused a slight stimulation of cellular growth at very low concentrations. At toxic concentrations, a dose-related but nonspecific inhibition of cell growth occurred. The cytotoxic changes included the decreased migration of cells from the culture implant, varicosities in and shortening of various cells and vacuolization and rounding of neuroglial cells. At high concentrations, pigmentary degeneration and complete abolition of cell growth were observed. The toxic effects were numerically scored in a random blind fashion and the concentrations of individual chemicals to produce a half maximal effect (IC50) in culture were determined from the dose-response curves. The IC50 values for various chemicals ranged from approximately 10(-6) M for compounds like methylparathion, diazinon, paraoxon and Vendex to greater than 10(-2) M for chlorpyriphos and methylchlorpyriphos. No significant correlations of nerve fiber or glial cell cytotoxicity were apparent with other toxic or physico-chemical properties such as lethal dose in animals, cholinesterase inhibition, lipophilicity or water solubility of chemicals. Clinically neurotoxic and nonneurotoxic compounds caused similar cytotoxic effects in ganglia cultures. Images Fig. 3. Fig. 4. Fig. 5. Fig. 6. PMID:7272842

Sharma, R P; Obersteiner, E J

1981-01-01

386

Abnormal pressures as hydrodynamic phenomena  

USGS Publications Warehouse

So-called abnormal pressures, subsurface fluid pressures significantly higher or lower than hydrostatic, have excited speculation about their origin since subsurface exploration first encountered them. Two distinct conceptual models for abnormal pressures have gained currency among earth scientists. The static model sees abnormal pressures generally as relict features preserved by a virtual absence of fluid flow over geologic time. The hydrodynamic model instead envisions abnormal pressures as phenomena in which flow usually plays an important role. This paper develops the theoretical framework for abnormal pressures as hydrodynamic phenomena, shows that it explains the manifold occurrences of abnormal pressures, and examines the implications of this approach. -from Author

Neuzil, C.E.

1995-01-01

387

Behaviour of oil ganglia displaced by a surfactant solution in a porous medium  

E-print Network

L-97 Behaviour of oil ganglia displaced by a surfactant solution in a porous medium J. C. Moulu'importance relative des forces de viscosité et des forces capillaires. Abstract. 2014 The velocity of oil ganglia residual oil phase by water injection in a porous medium [1, 2]. These studies have demonstrated

Boyer, Edmond

388

Locust flight behavior after hemisection of individual thoracic ganglia: evidence for hemiganglionic premotor centers  

Microsoft Academic Search

The flight behavior of locusts with hemisected mesothoracic or metathoracic ganglia was observed in unrestrained animals and monitored electromyographically in tethered animals. Animals with hemisected mesothoracic ganglia were able to initiate and carry out free flight. Hemisection of the mesothoracic ganglion caused no significant changes in the pattern of flight muscle firing; both intra- and intersegmental coordination of flight muscle

Bernhard Ronacher; Harald Wolf; Heinrich Reichert

1988-01-01

389

The mammalian sympathetic prevertebral ganglia: Models for the study of neuronal networks and basic neuronal properties  

Microsoft Academic Search

The mammalian sympathetic prevertebral ganglia regulate various visceral functions and in particular the digestive tract motility. Several integrative properties of these ganglia have been described: convergence of central inputs, projection of visceral inputs at the pre- and post synaptic level and pacemaker activity of the neurones. This review presents the results obtained on another integrative property which has been widely

Caroline Fasano; Jean-Pierre Niel

2009-01-01

390

Thalassemia and abnormal hemoglobin  

Microsoft Academic Search

Thalassemia and abnormal hemoglobins are common genetic disorders in Asia. Thalassemia is not only an important public health\\u000a problem but also a socio-economic problem of many countries in the region. The approach to deal with the thalassemic problem\\u000a is to prevent and control birth of new cases. This requires an accurate identification of the couple at high risk for thalassemia.

Suthat Fucharoen; Pranee Winichagoon

2002-01-01

391

Anatomical Abnormalities in Autism?  

PubMed

Substantial controversy exists regarding the presence and significance of anatomical abnormalities in autism spectrum disorders (ASD). The release of the Autism Brain Imaging Data Exchange (?1000 participants, age 6-65 years) offers an unprecedented opportunity to conduct large-scale comparisons of anatomical MRI scans across groups and to resolve many of the outstanding questions. Comprehensive univariate analyses using volumetric, thickness, and surface area measures of over 180 anatomically defined brain areas, revealed significantly larger ventricular volumes, smaller corpus callosum volume (central segment only), and several cortical areas with increased thickness in the ASD group. Previously reported anatomical abnormalities in ASD including larger intracranial volumes, smaller cerebellar volumes, and larger amygdala volumes were not substantiated by the current study. In addition, multivariate classification analyses yielded modest decoding accuracies of individuals' group identity (<60%), suggesting that the examined anatomical measures are of limited diagnostic utility for ASD. While anatomical abnormalities may be present in distinct subgroups of ASD individuals, the current findings show that many previously reported anatomical measures are likely to be of low clinical and scientific significance for understanding ASD neuropathology as a whole in individuals 6-35 years old. PMID:25316335

Haar, Shlomi; Berman, Sigal; Behrmann, Marlene; Dinstein, Ilan

2014-10-14

392

Feeling Abnormal: Simulation of Deviancy in Abnormal and Exceptionality Courses.  

ERIC Educational Resources Information Center

Describes activity in which student in abnormal psychology and psychology of exceptional children classes personally experience being judged abnormal. The experience allows the students to remember relevant research, become sensitized to the feelings of individuals classified as deviant, and use caution in classifying individuals as abnormal.…

Fernald, Charles D.

1980-01-01

393

Airway basal cells. The "smoking gun" of chronic obstructive pulmonary disease.  

PubMed

The earliest abnormality in the lung associated with smoking is hyperplasia of airway basal cells, the stem/progenitor cells of the ciliated and secretory cells that are central to pulmonary host defense. Using cell biology and 'omics technologies to assess basal cells isolated from bronchoscopic brushings of nonsmokers, smokers, and smokers with chronic obstructive pulmonary disease (COPD), compelling evidence has been provided in support of the concept that airway basal cells are central to the pathogenesis of smoking-associated lung diseases. When confronted by the chronic stress of smoking, airway basal cells become disorderly, regress to a more primitive state, behave as dictated by their inheritance, are susceptible to acquired changes in their genome, lose the capacity to regenerate the epithelium, are responsible for the major changes in the airway that characterize COPD, and, with persistent stress, can undergo malignant transformation. Together, these observations led to the conclusion that accelerated loss of lung function in susceptible individuals begins with disordered airway basal cell biology (i.e., that airway basal cells are the "smoking gun" of COPD, a potential target for the development of therapies to prevent smoking-related lung disorders). PMID:25354273

Crystal, Ronald G

2014-12-15

394

A possible defensive mechanism in the basal region of gastric mucosa and the healing of erosions.  

PubMed

A possible defensive mechanism in the basal region of the gastric mucosa was hypothesized in the present study. In vivo microscopy was performed to observe the basal region after thermal injury to the back skin of rats. A donor of nitric oxide, 3-morpholinosydnonimine hydrochloride (SIN-1), or a serine protease inhibitor, camostat mesilate, was administered. Anti-vascular endothelial growth factor (VEGF) neutralizing antibody was administered 5 hours after thermal injury (anti-VEGF group). Post-capillary venules could be observed in the basal region of the gastric mucosa (PV-BGM). The PV-BGM was dilated 5 hours after thermal injury, and it was reduced by the administration of SIN-1 or pre-treatment with camostat mesilate. In the control group, the erosions did not reach the basal region of the gastric mucosa. Most of the erosions healed within 72 hours. Delayed healing was observed in the anti-VEGF group. In this group, exudation and congestion in the basal region were observed at 24 hours, and ulcer formation was observed at 72 hours after thermal injury. It is thus hypothesized that blood flow of the PV-BGM increases when superficial mucosal circulation is disturbed. The PV-BGM can contribute to defensive mechanisms in the basal region of gastric mucosa. The abnormal healing process may disturb the defensive mechanism at the base of the gastric mucosa, thereby resulting in ulcer formation. PMID:14724355

Yoshida, Masashi; Wakabayashi, Go; Ishikawa, Hideki; Kameyama, Kaori; Shimazu, Motohide; Tanabe, Minoru; Kawachi, Shigeyuki; Kumai, Koichiro; Kubota, Tetsuro; Otani, Yoshihide; Saikawa, Yoshiro; Sano, Katsuko; Kitajima, Masaki

2003-01-01

395

Changes in P2X 3 purinoceptors in sensory ganglia of the mouse during embryonic and postnatal development  

Microsoft Academic Search

The expression of the P2X 3 nucleotide receptor in embryonic day 14–18, postnatal day 1–14 and adult mouse sensory ganglia was examined using immunohistochemistry. Nearly all sensory neurons in dorsal root ganglia, trigeminal ganglia and nodose ganglia in embryos at embryonic day 14 expressed P2X 3 receptors, but after birth there was a gradual decline to about 50% of neurons showing positive immunostaining

Huai Zhen Ruan; Eamonn Moules; Geoffrey Burnstock

2004-01-01

396

Exercises to Improve Gait Abnormalities  

MedlinePLUS

... Home About Goals Articles Directories Videos Resources Contact Exercises to Improve Gait Abnormalities Home » Article Categories » Exercise and Fitness Font Size: A A A A Exercises to Improve Gait Abnormalities Next Page The manner ...

397

Abnormal human sex chromosome constitutions  

SciTech Connect

Chapter 22, discusses abnormal human sex chromosome constitution. Aneuploidy of X chromosomes with a female phenotype, sex chromosome aneuploidy with a male phenotype, and various abnormalities in X chromosome behavior are described. 31 refs., 2 figs.

NONE

1993-12-31

398

Prenatal screening for chromosome abnormalities  

Microsoft Academic Search

An abnormal chromosome complement (aneuploidy) contributes significantly to fetal loss during pregnancy, as well as to perinatal morbidity and mortality. The contribution of chromosomal abnormalities to fetal loss decreases as pregnancy continues with an estimated 50% of first trimester spontaneous abortions due to chromosomal abnormalities, but only 5% of stillbirths (after 28 weeks). Prenatal screening for aneuploidy (in particular Down

Lyn Chitty

399

An essential role of the basal body protein SAS-6 in Plasmodium male gamete development and malaria transmission.  

PubMed

Gametocytes are the sole Plasmodium parasite stages that infect mosquitoes; therefore development of functional gametes is required for malaria transmission. Flagellum assembly of the Plasmodium male gamete differs from that of most other eukaryotes in that it is intracytoplasmic but retains a key conserved feature: axonemes assemble from basal bodies. The centriole/basal body protein SAS-6 normally regulates assembly and duplication of these organelles and its depletion causes severe flagellar/ciliary abnormalities in a diverse array of eukaryotes. Since basal body and flagellum assembly are intimately coupled to male gamete development in Plasmodium, we hypothesized that SAS-6 disruption may cause gametogenesis defects and perturb transmission. We show that Plasmodium berghei?sas6 knockouts display severely abnormal male gametogenesis presenting reduced basal body numbers, axonemal assembly defects and abnormal nuclear allocation. The defects in gametogenesis reduce fertilization and render Pbsas6 knockouts less infectious to mosquitoes. Additionally, we show that lack of Pbsas6 blocks transmission from mosquito to vertebrate host, revealing an additional yet undefined role in ookinete to sporulating oocysts transition. These findings underscore the vulnerability of the basal body/SAS-6 to malaria transmission blocking interventions. PMID:25154861

Marques, Sara R; Ramakrishnan, Chandra; Carzaniga, Raffaella; Blagborough, Andrew M; Delves, Michael J; Talman, Arthur M; Sinden, Robert E

2015-02-01

400

Maintenance of Basal Levels of Autophagy in Huntington’s Disease Mouse Models Displaying Metabolic Dysfunction  

PubMed Central

Huntington’s disease (HD) is a fatal neurodegenerative disorder caused by an expanded polyglutamine repeat in the huntingtin protein. Neuropathology in the basal ganglia and in the cerebral cortex has been linked to the motor and cognitive symptoms whereas recent work has suggested that the hypothalamus might be involved in the metabolic dysfunction. Several mouse models of HD that display metabolic dysfunction have hypothalamic pathology, and expression of mutant huntingtin in the hypothalamus has been causally linked to the development of metabolic dysfunction in mice. Although the pathogenic mechanisms by which mutant huntingtin exerts its toxic functions in the HD brain are not fully known, several studies have implicated a role for the lysososomal degradation pathway of autophagy. Interestingly, changes in autophagy in the hypothalamus have been associated with the development of metabolic dysfunction in wild-type mice. We hypothesized that expression of mutant huntingtin might lead to changes in the autophagy pathway in the hypothalamus in mice with metabolic dysfunction. We therefore investigated whether there were changes in basal levels of autophagy in a mouse model expressing a fragment of 853 amino acids of mutant huntingtin selectively in the hypothalamus using a recombinant adeno-associate viral vector approach as well as in the transgenic BACHD mice. We performed qRT-PCR and Western blot to investigate the mRNA and protein expression levels of selected autophagy markers. Our results show that basal levels of autophagy are maintained in the hypothalamus despite the presence of metabolic dysfunction in both mouse models. Furthermore, although there were no major changes in autophagy in the striatum and cortex of BACHD mice, we detected modest, but significant differences in levels of some markers in mice at 12 months of age. Taken together, our results indicate that overexpression of mutant huntingtin in mice do not significantly perturb basal levels of autophagy. PMID:24376631

Baldo, Barbara; Soylu, Rana; Petersén, Åsa

2013-01-01

401

Dorsal Root Ganglia Damage in SIV-Infected Rhesus Macaques  

PubMed Central

HIV-associated sensory neuropathy (HIV-SN) is currently the most common neurological complication of chronic HIV infection and continues to substantially affect patient quality of life. Mechanisms underlying the neuronal damage and loss observed in sensory ganglia of HIV-infected individuals have not been sufficiently studied. The present study aimed to develop and characterize a model of HIV-SN using SIV-infected CD8 T-lymphocyte-depleted rhesus macaques (Macaca mulatta). Uninfected controls (n = 5), SIV-infected CD8-depleted (n = 4), and SIV-infected non-CD8-depleted (n = 6) animals were used. Of the six non-CD8-depleted animals, three were conventional progressors (progressing to AIDS >1 year after infection) and three were rapid progressors (AIDS within 6 months). Dorsal root ganglia (DRG) were examined for histological hallmarks of HIV-SN, including satellitosis, presence of Nageotte nodules, and neuronophagia, as well as increased numbers of CD68+ macrophages and abundant viral replication. In contrast to non-CD8-depleted animals, which had mild to moderate DRG pathology, the CD8-depleted SIV-infected animals had moderate to severe DRG damage, with increased numbers of CD68+ satellite cells. Additionally, there was marked active viral replication in the affected DRG. These findings confirm that many features of HIV-SN can be recapitulated in the CD8-depleted SIV-infected rhesus macaque model within a short time frame and illustrate the importance of this model for study of sensory neuropathy. PMID:22322298

Burdo, Tricia H.; Orzechowski, Krystyna; Knight, Heather L.; Miller, Andrew D.; Williams, Kenneth

2012-01-01

402

Metastatic Basal Cell Carcinoma Accompanying Gorlin Syndrome  

PubMed Central

Gorlin-Goltz syndrome or basal cell nevus syndrome is an autosomal dominant syndrome characterized by skeletal anomalies, numerous cysts observed in the jaw, and multiple basal cell carcinoma of the skin, which may be accompanied by falx cerebri calcification. Basal cell carcinoma is the most commonly skin tumor with slow clinical course and low metastatic potential. Its concomitance with Gorlin syndrome, resulting from a mutation in a tumor suppressor gene, may substantially change morbidity and mortality. A 66-year-old male patient with a history of recurrent basal cell carcinoma was presented with exophthalmus in the left eye and the lesions localized in the left lateral orbita and left zygomatic area. His physical examination revealed hearing loss, gapped teeth, highly arched palate, and frontal prominence. Left orbital mass, cystic masses at frontal and ethmoidal sinuses, and multiple pulmonary nodules were detected at CT scans. Basal cell carcinoma was diagnosed from biopsy of ethmoid sinus. Based on the clinical and typical radiological characteristics (falx cerebri calcification, bifid costa, and odontogenic cysts), the patient was diagnosed with metastatic skin basal cell carcinoma accompanied by Gorlin syndrome. Our case is a basal cell carcinoma with aggressive course accompanying a rarely seen syndrome. PMID:25506011

Bilir, Yeliz; Gokce, Erkan; Ozturk, Banu; Deresoy, Faik Alev; Yuksekkaya, Ruken; Yaman, Emel

2014-01-01

403

Frequency and Abundance of Alphaherpesvirus DNA in Human Thoracic Sympathetic Ganglia  

PubMed Central

Alphaherpesvirus reactivation from thoracic sympathetic ganglia (TSG) and transaxonal spread to target organs cause human visceral disease. Yet alphaherpesvirus latency in TSG has not been well characterized. In this study, quantitative PCR detected varicella-zoster virus (VZV), herpes simplex virus 1 (HSV-1), and HSV-2 DNA in 117 fresh TSG obtained postmortem from 15 subjects. VZV DNA was found in 76 (65%) ganglia from all subjects, HSV-1 DNA was found in 5 (4%) ganglia from 3 subjects, and no HSV-2 was found. PMID:24789785

Rempel, April; Huntington, Jonathon; Kim, Forrest; Choe, Alexander; Gilden, Don

2014-01-01

404

A Rare Stapes Abnormality  

PubMed Central

The aim of this study is to increase awareness of rare presentations, diagnostic difficulties alongside management of conductive hearing loss and ossicular abnormalities. We report the case of a 13-year-old female reporting progressive left-sided hearing loss and high resolution computed tomography was initially reported as normal. Exploratory tympanotomy revealed an absent stapedius tendon and lack of connection between the stapes superstructure and footplate. The footplate was fixed. Stapedotomy and stapes prosthesis insertion resulted in closure of the air-bone gap by 50?dB. A review of world literature was performed using MedLine. Middle ear ossicular discontinuity can result in significant conductive hearing loss. This can be managed effectively with surgery to help restore hearing. However, some patients may not be suitable or decline surgical intervention and can be managed safely conservatively. PMID:25628909

Kanona, Hala; Virk, Jagdeep Singh; Kumar, Gaurav; Chawda, Sanjiv; Khalil, Sherif

2015-01-01

405

A rare stapes abnormality.  

PubMed

The aim of this study is to increase awareness of rare presentations, diagnostic difficulties alongside management of conductive hearing loss and ossicular abnormalities. We report the case of a 13-year-old female reporting progressive left-sided hearing loss and high resolution computed tomography was initially reported as normal. Exploratory tympanotomy revealed an absent stapedius tendon and lack of connection between the stapes superstructure and footplate. The footplate was fixed. Stapedotomy and stapes prosthesis insertion resulted in closure of the air-bone gap by 50?dB. A review of world literature was performed using MedLine. Middle ear ossicular discontinuity can result in significant conductive hearing loss. This can be managed effectively with surgery to help restore hearing. However, some patients may not be suitable or decline surgical intervention and can be managed safely conservatively. PMID:25628909

Kanona, Hala; Virk, Jagdeep Singh; Kumar, Gaurav; Chawda, Sanjiv; Khalil, Sherif

2015-01-01

406

Basal constriction : shaping the vertebrate brain  

E-print Network

Organs are primarily formed from epithelia, polarized sheets of cells with an apical surface facing a lumen and basal surface resting on the underlying extracellular matrix. Cells within a sheet are joined by junctions, ...

Graeden, Ellie Graham

2011-01-01

407

Students' reactions to abnormal psychology  

Microsoft Academic Search

As a result of some concern about the effect of courses in abnormal psychology on students, a questionnaire was presented to several classes at the close of the course. The majority answering the questionnaire felt the course to be beneficial, giving evidence that the study of abnormal psychology need not be generally harmful, and may have a significant place in

W. S. Taylor

1932-01-01

408

abnormalities in infants and toddlers  

E-print Network

, Akshoomoff 2000). Similarly, patients with fetal alcohol syndrome (FAS) have decreased cerebellar volumesCerebellar abnormalities in infants and toddlers with Williams syndrome Wendy Jones* PhD, The Salk-mail: jones@crl.ucsd.edu One commonly observed neuroanatomical abnormality in adults with Williams syndrome

Bellugi, Ursula

409

Abnormal pressure in hydrocarbon environments  

USGS Publications Warehouse

Abnormal pressures, pressures above or below hydrostatic pressures, occur on all continents in a wide range of geological conditions. According to a survey of published literature on abnormal pressures, compaction disequilibrium and hydrocarbon generation are the two most commonly cited causes of abnormally high pressure in petroleum provinces. In young (Tertiary) deltaic sequences, compaction disequilibrium is the dominant cause of abnormal pressure. In older (pre-Tertiary) lithified rocks, hydrocarbon generation, aquathermal expansion, and tectonics are most often cited as the causes of abnormal pressure. The association of abnormal pressures with hydrocarbon accumulations is statistically significant. Within abnormally pressured reservoirs, empirical evidence indicates that the bulk of economically recoverable oil and gas occurs in reservoirs with pressure gradients less than 0.75 psi/ft (17.4 kPa/m) and there is very little production potential from reservoirs that exceed 0.85 psi/ft (19.6 kPa/m). Abnormally pressured rocks are also commonly associated with unconventional gas accumulations where the pressuring phase is gas of either a thermal or microbial origin. In underpressured, thermally mature rocks, the affected reservoirs have most often experienced a significant cooling history and probably evolved from an originally overpressured system.

Law, B.E.; Spencer, C.W.

1998-01-01

410

A basal water model for ice sheets  

NASA Astrophysics Data System (ADS)

A previously existing ice sheet model is described. The model accounts for ice deformation, themo-mechanical coupling, isostasy, and simple climatology. After reviewing the current and past literature pertaining to the melt water systems that exist within glaciers and ice sheets, a basal water model for ice sheets is formulated. The model takes the form of a conservation equation for basal water coupled with a relationship for the velocity of basal water and an expression for the potential field experienced by the basal water system. The model also accounts for basal water flowing through a permeable under-layer based on some assumptions about the till that is under ice sheets. The differential equations that arise from formulation of the model are solved numerically with the finite element method. The model is tested for its sensitivity to various physical parameters. A sliding law is formulated in terms of the basal water distribution. The first set of tests is conducted on the Ross Ice Streams of Antarctica. The parameters considered are the interaction with the aquifer and the velocity of the water. The study demonstrates that with a proper sliding law, an accurate reproduction of the positions and the velocities of the Ross Ice Streams is possible. The second sensitivity test considers the glaciation and de-glaciation of the Northern Hemisphere. The second test demonstrates a clear advantage of ice sheet models that use a basal water distribution to estimate sliding over models that simply have sliding where ever the bed is thawed. With a basal water model for ice sheets, it is possible to identify sub-glacial lakes from geographic data sets. This is done in Antarctica. The position of the sub-glacial lakes identified from data sets compares favorably with the position of sub-glacial lakes identified in field studies. The set of sub-glacial lakes are analyzed for their stability and potential contribution to a basal water system. It is shown that sub-glacial lakes can play a significant role in maintaining or stagnating ice streams.

Johnson, Jesse Virgil

411

Basal Cell Carcinoma in a Child  

PubMed Central

Basal cell carcinoma is the most commonly seen nonmelanoma skin cancer which is rarely encountered in the childhood period. An 11-year old child was admitted to our clinic due to an erythematous and a slightly pigmented lesion with a 3 × 4?cm diameter on his posterior scalp. Macroscopically, the lesion was excised with a 10?mm safety margin. Pathologic examination revealed a basal cell carcinoma. No symptoms or signs of a syndrome were observed both in the patient and his family. PMID:21188232

Kuvat, Samet Vasfi; Gücin, Zuhal; Keklik, Bar??; Özyalvaçl?, Gülzade; Ba?aran, Karaca

2011-01-01

412

Intraneuronal angiotensinergic system in rat and human dorsal root ganglia  

PubMed Central

To elucidate the local formation of angiotensin II (Ang II) in the neurons of sensory dorsal root ganglia (DRG), we studied the expression of angiotensinogen (Ang-N)-, renin-, angiotensin converting enzyme (ACE)- and cathepsin D-mRNA, and the presence of protein renin, Ang II, Substance P and calcitonin gene-related peptide (CGRP) in the rat and human thoracic DRG. Quantitative real time PCR (qRT-PCR) studies revealed that rat DRG expressed substantial amounts of Ang-N- and ACE mRNA, while renin mRNA as well as the protein renin were untraceable. Cathepsin D-mRNA and cathepsin D-protein were detected in the rat DRG indicating the possibility of existence of pathways alternative to renin for Ang I formation. Angiotensin peptides were successfully detected with high performance liquid chromatography and radioimmunoassay in human DRG extracts. In situ hybridization in rat DRG confirmed additionally expression of Ang-N mRNA in the cytoplasm of numerous neurons. Intracellular Ang II staining could be shown in number of neurons and their processes in both the rat and human DRG. Interestingly we observed neuronal processes with angiotensinergic synapses en passant, colocalized with synaptophysin, within the DRG. In the DRG, we also identified by qRT-PCR, expression of Ang II receptor AT1A and AT2-mRNA while AT1B-mRNA was not traceable. In some neurons Substance P and CGRP were found colocalized with Ang II. The intracellular localization and colocalization of Ang II with Substance P and CGRP in the DRG neurons may indicate a participation and function of Ang II in the regulation of nociception. In conclusion, these results suggest that Ang II may be produced locally in the neurons of rat and human DRG and act as a neurotransmitter. PMID:20346377

Patil, Jaspal; Schwab, Alexander; Nussberger, Juerg; Schaffner, Thomas; Saavedra, Juan M.; Imboden, Hans

2010-01-01

413

Invited Article: Autonomic ganglia: target and novel therapeutic tool.  

PubMed

Nicotinic acetylcholine receptors (AChR) are ligand-gated cation channels that are present throughout the nervous system. The muscle AChR mediates transmission at the neuromuscular junction; antibodies against the muscle AChR are the cause of myasthenia gravis. The ganglionic (alpha 3-type) neuronal AChR mediates fast synaptic transmission in sympathetic, parasympathetic, and enteric autonomic ganglia. Impaired cholinergic ganglionic synaptic transmission is one important cause of autonomic failure. Pharmacologic enhancement of ganglionic synaptic transmission may be a novel way to improve autonomic function. Ganglionic AChR antibodies are found in patients with autoimmune autonomic ganglionopathy (AAG). Patients with AAG typically present with rapid onset of severe autonomic failure. Major clinical features include orthostatic hypotension, gastrointestinal dysmotility, anhidrosis, bladder dysfunction, and sicca symptoms. Impaired pupillary light reflex is often seen. Like myasthenia, AAG is an antibody-mediated neurologic disorder. The disease can be reproduced in experimental animals by active immunization or passive antibody transfer. The patient may improve with plasma exchange treatment or other immunomodulatory treatment. Antibodies from patients with AAG inhibit ganglionic AChR currents. Other phenotypes of AAG are now recognized based on the results of antibody testing. These other presentations are generally associated with lower levels of ganglionic AChR antibodies. A chronic progressive form of AAG may resemble pure autonomic failure. Milder forms of dysautonomia, such as postural tachycardia syndrome, are associated with ganglionic AChR in 10-15% of cases. Since ganglionic synaptic transmission is a common pathway for all autonomic traffic, enhancement of autonomic function through inhibition of acetylcholinesterase is a potential specific therapeutic strategy for autonomic disorders. Increasing the strength of ganglionic transmission can ameliorate neurogenic orthostatic hypotension without aggravating supine hypertension. Recent evidence also suggests a potential role for acetylcholinesterase inhibitors in the treatment of postural tachycardia syndrome. PMID:18474849

Vernino, Steven; Sandroni, Paola; Singer, Wolfgang; Low, Phillip A

2008-05-13

414

Mitochondrial Respiratory Chain Dysfunction in Dorsal Root Ganglia of Streptozotocin-Induced Diabetic Rats and Its Correction by Insulin Treatment  

PubMed Central

OBJECTIVE Impairments in mitochondrial physiology may play a role in diabetic sensory neuropathy. We tested the hypothesis that mitochondrial dysfunction in sensory neurons is due to abnormal mitochondrial respiratory function. RESEARCH DESIGN AND METHODS Rates of oxygen consumption were measured in mitochondria from dorsal root ganglia (DRG) of 12- to- 22-week streptozotocin (STZ)-induced diabetic rats, diabetic rats treated with insulin, and age-matched controls. Activities and expression of components of mitochondrial complexes and reactive oxygen species (ROS) were analyzed. RESULTS Rates of coupled respiration with pyruvate + malate (P + M) and with ascorbate + TMPD (Asc + TMPD) in DRG were unchanged after 12 weeks of diabetes. By 22 weeks of diabetes, respiration with P + M was significantly decreased by 31–44% and with Asc + TMPD by 29–39% compared with control. Attenuated mitochondrial respiratory activity of STZ-diabetic rats was significantly improved by insulin that did not correct other indices of diabetes. Activities of mitochondrial complexes I and IV and the Krebs cycle enzyme, citrate synthase, were decreased in mitochondria from DRG of 22-week STZ-diabetic rats compared with control. ROS levels in perikarya of DRG neurons were not altered by diabetes, but ROS generation from mitochondria treated with antimycin A was diminished compared with control. Reduced mitochondrial respiratory function was associated with downregulation of expression of mitochondrial proteins. CONCLUSIONS Mitochondrial dysfunction in sensory neurons from type 1 diabetic rats is associated with impaired rates of respiratory activity and occurs without a significant rise in perikaryal ROS. PMID:20103706

Chowdhury, Subir K. Roy; Zherebitskaya, Elena; Smith, Darrell R.; Akude, Eli; Chattopadhyay, Sharmila; Jolivalt, Corinne G.; Calcutt, Nigel A.; Fernyhough, Paul

2010-01-01

415

RNA complementary to herpes simplex virus type 1 ICP0 gene demonstrated in neurons of human trigeminal ganglia.  

PubMed Central

Recent studies with mice have demonstrated abundant RNA transcripts which are complementary (antisense) to the herpes alpha gene ICP0 in latently infected ganglia. We investigated the situation in unselected human trigeminal ganglia. Strand-specific 2.7-kilobase herpes simplex virus type 1 (HSV-1) ICP0 RNA probes were prepared, and their sense was determined in productively infected cells. Although in situ hybridization demonstrated ICP0 antisense RNA transcripts in the nuclei of neurons in 46% of the ganglia, ICP0 messenger RNA was not found in any of the ganglia. We conclude that HSV-1 antisense ICP0 RNA is present in humans during ganglionic latency. Images PMID:2451758

Gordon, Y J; Johnson, B; Romanowski, E; Araullo-Cruz, T

1988-01-01