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Sample records for neural plasticity habituation

  1. Habituation in non-neural organisms: evidence from slime moulds.

    PubMed

    Boisseau, Romain P; Vogel, David; Dussutour, Audrey

    2016-04-27

    Learning, defined as a change in behaviour evoked by experience, has hitherto been investigated almost exclusively in multicellular neural organisms. Evidence for learning in non-neural multicellular organisms is scant, and only a few unequivocal reports of learning have been described in single-celled organisms. Here we demonstrate habituation, an unmistakable form of learning, in the non-neural organism Physarum polycephalum In our experiment, using chemotaxis as the behavioural output and quinine or caffeine as the stimulus, we showed that P. polycephalum learnt to ignore quinine or caffeine when the stimuli were repeated, but responded again when the stimulus was withheld for a certain time. Our results meet the principle criteria that have been used to demonstrate habituation: responsiveness decline and spontaneous recovery. To distinguish habituation from sensory adaptation or motor fatigue, we also show stimulus specificity. Our results point to the diversity of organisms lacking neurons, which likely display a hitherto unrecognized capacity for learning, and suggest that slime moulds may be an ideal model system in which to investigate fundamental mechanisms underlying learning processes. Besides, documenting learning in non-neural organisms such as slime moulds is centrally important to a comprehensive, phylogenetic understanding of when and where in the tree of life the earliest manifestations of learning evolved. PMID:27122563

  2. Neural networks of tinnitus in humans: Elucidating severity and habituation.

    PubMed

    Husain, Fatima T

    2016-04-01

    The article reviews current data about the neural correlates of an individual's reaction to tinnitus, primarily from studies that employ magnetic resonance imaging (MRI). Human studies employing brain imaging remain the most commonly used method to understand neural biomarkers of the reaction to tinnitus, a subjective hearing disorder. Evidence from anatomical and functional MRI studies is reviewed to better understand the large-scale neural networks implicated in tinnitus habituation and severity. These networks are concerned with attention, audition, and emotion, both during tasks and at 'rest' when no goal-directed activity is expected. I place the data in the context of published literature and current theories about tinnitus severity, while explaining the challenges and limitations of human MRI studies. A possible model of habituation to tinnitus is described, that of the attention system (via the frontal cortex) suppressing the response from the amygdala and the use of alternate nodes of the limbic system such as the insula and the parahippocampal gyrus when mediating emotion. PMID:26415997

  3. Gustatory Habituation in "Drosophila" Relies on "Rutabaga" (Adenylate Cyclase)-Dependent Plasticity of GABAergic Inhibitory Neurons

    ERIC Educational Resources Information Center

    Paranjpe, Pushkar; Rodrigues, Veronica; VijayRaghavan, K.; Ramaswami, Mani

    2012-01-01

    In some situations, animals seem to ignore stimuli which in other contexts elicit a robust response. This attenuation in behavior, which enables animals to ignore a familiar, unreinforced stimulus, is called habituation. Despite the ubiquity of this phenomenon, it is generally poorly understood in terms of the underlying neural circuitry. Hungry…

  4. Neural prostheses and brain plasticity

    NASA Astrophysics Data System (ADS)

    Fallon, James B.; Irvine, Dexter R. F.; Shepherd, Robert K.

    2009-12-01

    The success of modern neural prostheses is dependent on a complex interplay between the devices' hardware and software and the dynamic environment in which the devices operate: the patient's body or 'wetware'. Over 120 000 severe/profoundly deaf individuals presently receive information enabling auditory awareness and speech perception from cochlear implants. The cochlear implant therefore provides a useful case study for a review of the complex interactions between hardware, software and wetware, and of the important role of the dynamic nature of wetware. In the case of neural prostheses, the most critical component of that wetware is the central nervous system. This paper will examine the evidence of changes in the central auditory system that contribute to changes in performance with a cochlear implant, and discuss how these changes relate to electrophysiological and functional imaging studies in humans. The relationship between the human data and evidence from animals of the remarkable capacity for plastic change of the central auditory system, even into adulthood, will then be examined. Finally, we will discuss the role of brain plasticity in neural prostheses in general.

  5. Phantom limbs and neural plasticity.

    PubMed

    Ramachandran, V S; Rogers-Ramachandran, D

    2000-03-01

    The study of phantom limbs has received tremendous impetus from recent studies linking changes in cortical topography with perceptual experience. Systematic psychophysical testing and functional imaging studies on patients with phantom limbs provide 2 unique opportunities. First, they allow us to demonstrate neural plasticity in the adult human brain. Second, by tracking perceptual changes (such as referred sensations) and changes in cortical topography in individual patients, we can begin to explore how the activity of sensory maps gives rise to conscious experience. Finally, phantom limbs also allow us to explore intersensory effects and the manner in which the brain constructs and updates a "body image" throughout life. PMID:10714655

  6. Neural Correlates of Empathy with Pain Show Habituation Effects. An fMRI Study

    PubMed Central

    Preis, Mira A.; Kröner-Herwig, Birgit; Schmidt-Samoa, Carsten; Dechent, Peter; Barke, Antonia

    2015-01-01

    Background Neuroimaging studies have demonstrated that the actual experience of pain and the perception of another person in pain share common neural substrates, including the bilateral anterior insular cortex and the anterior midcingulate cortex. As many fMRI studies include the exposure of participants to repeated, similar stimuli, we examined whether empathic neural responses were affected by habituation and whether the participants' prior pain experience influenced these habituation effects. Method In 128 trials (four runs), 62 participants (31 women, 23.0 ± 4.2 years) were shown pictures of hands exposed to painful pressure (pain pictures) and unexposed (neutral pictures). After each trial, the participants rated the pain of the model. Prior to the experiment, participants were either exposed to the same pain stimulus (pain exposure group) or not (touch exposure group). In order to assess possible habituation effects, linear changes in the strength of the BOLD response to the pain pictures (relative to the neutral pictures) and in the ratings of the model’s pain were evaluated across the four runs. Results Although the ratings of the model’s pain remained constant over time, we found neural habituation in the bilateral anterior/midinsular cortex, the posterior midcingulate extending to dorsal posterior cingulate cortex, the supplementary motor area, the cerebellum, the right inferior parietal lobule, and the left superior frontal gyrus, stretching to the pregenual anterior cingulate cortex. The participant’s prior pain experience did neither affect their ratings of the model’s pain nor their maintenance of BOLD activity in areas associated with empathy. Interestingly, participants with high trait personal distress and fantasy tended to show less habituation in the anterior insula. Conclusion Neural structures showed a decrease of the BOLD signal, indicating habituation over the course of 45 minutes. This can be interpreted as a neuronal mechanism

  7. Visual recognition memory, manifest as long-term habituation, requires synaptic plasticity in V1

    PubMed Central

    Cooke, Sam F.; Komorowski, Robert W.; Kaplan, Eitan S.; Gavornik, Jeffrey P.; Bear, Mark F.

    2015-01-01

    Familiarity with stimuli that bring neither reward nor punishment, manifested through behavioural habituation, enables organisms to detect novelty and devote cognition to important elements of the environment. Here we describe in mice a form of long-term behavioural habituation to visual grating stimuli that is selective for stimulus orientation. Orientation-selective habituation (OSH) can be observed both in exploratory behaviour in an open arena, and in a stereotyped motor response to visual stimuli in head-restrained mice. We show that the latter behavioural response, termed a vidget, requires V1. Parallel electrophysiological recordings in V1 reveal that plasticity, in the form of stimulus-selective response potentiation (SRP), occurs in layer 4 of V1 as OSH develops. Local manipulations of V1 that prevent and reverse electrophysiological modifications likewise prevent and reverse memory demonstrated behaviourally. These findings suggest that a form of long-term visual recognition memory is stored via synaptic plasticity in primary sensory cortex. PMID:25599221

  8. Habituation-based mechanism for encoding temporal information in artificial neural networks

    NASA Astrophysics Data System (ADS)

    Stiles, Bryan W.; Ghosh, Joydeep

    1995-04-01

    A novel neural network is proposed for the dynamic classification of spatio-temporal signals. The network is designed to classify signals of different durations, taking into account correlations among different signal segments. Such a network is applicable to SONAR and speech signal classification problems, among others. Network parameters are adapted based on the biologically observed habituation mechanism. This allows the storage of contextual information, without a substantial increase in network complexity. Experiments on classification of high dimensional feature vectors obtained from Banzhaf sonograms, demonstrate that the proposed network performs better than time delay neural networks while using a less complex structure. A mathematical justification of the capabilities of the habituation based mechanism is also provided.

  9. Synaptic plasticity in the acoustic startle pathway: the neuronal basis for short-term habituation?

    PubMed

    Weber, Maruschka; Schnitzler, Hans-Ulrich; Schmid, Susanne

    2002-10-01

    The aim of the present study was to analyse the cellular mechanism underlying short-term habituation of the acoustic startle response (ASR). We explored distinct synapses of the neuronal startle pathway in rat brain slices by patch-clamp recordings of giant neurons in the caudal pontine reticular formation. Presynaptic stimulation of auditory afferents by repeated bursts at 0.1 and 1 Hz led to an exponential decay of EPSC magnitudes. This homosynaptic depression (HSD) was reversible and repeatedly inducible after recovery. Many parameters of HSD in vitro match those of ASR habituation in vivo. The mechanisms underlying HSD are distinct from classical short-term plasticity: paired-pulse as well as paired-burst stimulation revealed a facilitation of the second EPSC, occurring in a much smaller time window up to interstimulus intervals of 200 ms. Pharmacological experiments demonstrated that HSD could be completely blocked by the group II and III metabotropic glutamate receptor antagonist MPPG. Similar results were obtained by CPPG, another group II and III antagonist. In contrast, HSD was not affected by the group I and II antagonist MCPG. We conclude that we found a form of synaptic depression in synapses within the primary startle pathway which correlates in many respects with short-term habituation of the ASR and which is presumably mediated by group III metabotropic glutamate receptors. PMID:12405993

  10. Modeling habituation in rat EEG-evoked responses via a neural mass model with feedback

    PubMed Central

    Tadmor, Gilead; Diamond, Solomon G.; Miller, Eric; Franceschini, Maria Angela; Brooks, Dana H.

    2012-01-01

    Habituation is a generic property of the neural response to repeated stimuli. Its strength often increases as inter-stimuli relaxation periods decrease. We propose a simple, broadly applicable control structure that enables a neural mass model of the evoked EEG response to exhibit habituated behavior. A key motivation for this investigation is the ongoing effort to develop model-based reconstruction of multimodal functional neuroimaging data. The control structure proposed here is illustrated and validated in the context of a biophysical neural mass model, developed by Riera et al. (Hum Brain Mapp 27(11):896–914, 2006; 28(4):335–354, 2007), and of simplifications thereof, using data from rat EEG response to medial nerve stimuli presented at frequencies from 1 to 8 Hz. Performance was tested by predictions of both the response to the next stimulus based on the current one, and also of continued stimuli trains over 4-s time intervals based on the first stimulus in the interval, with similar success statistics. These tests demonstrate the ability of simple generative models to capture key features of the evoked response, including habituation. PMID:22282292

  11. Neural Plasticity in Speech Acquisition and Learning

    ERIC Educational Resources Information Center

    Zhang, Yang; Wang, Yue

    2007-01-01

    Neural plasticity in speech acquisition and learning is concerned with the timeline trajectory and the mechanisms of experience-driven changes in the neural circuits that support or disrupt linguistic function. In this selective review, we discuss the role of phonetic learning in language acquisition, the "critical period" of learning, the agents…

  12. Neural network simulation of habituation and dishabituation in infant speech perception

    NASA Astrophysics Data System (ADS)

    Gauthier, Bruno; Shi, Rushen; Proulx, Robert

    2001-05-01

    The habituation techniques used in infant speech perception studies are based on the fact that infants show renewed interest towards novel stimuli. Recent work has shown the possibility of using artificial neural networks to model habituation and dishabituation (e.g., Schafer and Mareschal, 2001). In our study we examine weather the self-organizing-feature-maps (SOM) (Kohonen, 1989) are appropriate for modeling short-term habituation to a repeated speech stimulus. We found that although SOMs are particularly useful for simulating categorization, they can be modified to model habituation and dishabituation, so that they can be applied to direct comparisons with behavioral data on infants' speech discrimination abilities. In particular, we modified the SOMs to include additional parameters that control the relation of input similarity, lateral inhibition, and local and lateral activation between neurons. Preliminary results suggest that these parameters are sufficient for the network to simulate the loss of sensitivity of the auditory system due to the presentation of multiple tokens of a speech stimulus, as well as to model the recovery of sensitivity to a novel stimulus. The implications of this approach to infant speech perception research will be considered.

  13. Mathematical Modeling of Neural Correlates of Cognition: The Case of Selective Attention and Habituation

    NASA Astrophysics Data System (ADS)

    Trenado, C.; Haab, L.; Strauss, D. J.

    2009-05-01

    Auditory evoked cortical potentials (AECPs) have extensively been applied in studies related to diagnosis and treatment of hearing disorders as well as cognitive and behavioral mechanisms. Regarding the mechanisms of attention and habituation, numerous studies involving electroencephalographic and magnetic resonance imaging techniques, emphasize the role of prominent cortico-subcortical brain structures as being implicated in a bidirectional processing and flux of sensory information with specific consequences for these processes. In spite of such progress, the effect of the interplay between prominent cortico-subcortical structures reflected in AECPs remains poorly understood. To address this issue, we propose a neuronal mean field approach for the study of neural correlates of selective attention and habituation in the case of the auditory modality. Such a framework is endowed with a neurophysiological interpretation so that we can formulate hypothesis concerning the mechanisms of selective attention and habituation. It is concluded that our approach represents a useful methodology for the study of neural correlates reflected in large-scale potentials.

  14. Prenatal and acute cocaine exposure affects neural responses and habituation to visual stimuli

    PubMed Central

    Riley, Elizabeth; Kopotiyenko, Konstantin; Zhdanova, Irina

    2015-01-01

    Psychostimulants have many effects on visual function, from adverse following acute and prenatal exposure to therapeutic on attention deficit. To determine the impact of prenatal and acute cocaine exposure on visual processing, we studied neuronal responses to visual stimuli in two brain regions of a transgenic larval zebrafish expressing the calcium indicator GCaMP-HS. We found that both red light (LF) and dark (DF) flashes elicited similar responses in the optic tectum neuropil (TOn), while the dorsal telencephalon (dTe) responded only to LF. Acute cocaine (0.5 μM) reduced neuronal responses to LF in both brain regions but did not affect responses to DF. Repeated stimulus presentation (RSP) led to habituation of dTe neurons to LF. Acute cocaine prevented habituation. TOn habituated to DF, but not LF, and DF habituation was not modified by cocaine. Remarkably, prenatal cocaine exposure (PCE) prevented the effects of acute cocaine on LF response amplitude and habituation later in development in both brain regions, but did not affect DF responses. We discovered that, in spite of similar neural responses to LF and DF in the TO (superior colliculus in mammals), responses to LF are more complex, involving dTe (homologous to the cerebral cortex), and are more vulnerable to cocaine. Our results demonstrate that acute cocaine exposure affects visual processing differentially by brain region, and that PCE modifies zebrafish visual processing in multiple structures in a stimulus-dependent manner. These findings are in accordance with the major role that the optic tectum and cerebral cortex play in sustaining visual attention, and support the hypothesis that modification of these areas by PCE may be responsible for visual deficits noted in humans. This model offers new methodological approaches for studying the adverse and therapeutic effects of psychostimulants on attention, and for the development of new pharmacological interventions. PMID:26379509

  15. Prenatal and acute cocaine exposure affects neural responses and habituation to visual stimuli.

    PubMed

    Riley, Elizabeth; Kopotiyenko, Konstantin; Zhdanova, Irina

    2015-01-01

    Psychostimulants have many effects on visual function, from adverse following acute and prenatal exposure to therapeutic on attention deficit. To determine the impact of prenatal and acute cocaine exposure on visual processing, we studied neuronal responses to visual stimuli in two brain regions of a transgenic larval zebrafish expressing the calcium indicator GCaMP-HS. We found that both red light (LF) and dark (DF) flashes elicited similar responses in the optic tectum neuropil (TOn), while the dorsal telencephalon (dTe) responded only to LF. Acute cocaine (0.5 μM) reduced neuronal responses to LF in both brain regions but did not affect responses to DF. Repeated stimulus presentation (RSP) led to habituation of dTe neurons to LF. Acute cocaine prevented habituation. TOn habituated to DF, but not LF, and DF habituation was not modified by cocaine. Remarkably, prenatal cocaine exposure (PCE) prevented the effects of acute cocaine on LF response amplitude and habituation later in development in both brain regions, but did not affect DF responses. We discovered that, in spite of similar neural responses to LF and DF in the TO (superior colliculus in mammals), responses to LF are more complex, involving dTe (homologous to the cerebral cortex), and are more vulnerable to cocaine. Our results demonstrate that acute cocaine exposure affects visual processing differentially by brain region, and that PCE modifies zebrafish visual processing in multiple structures in a stimulus-dependent manner. These findings are in accordance with the major role that the optic tectum and cerebral cortex play in sustaining visual attention, and support the hypothesis that modification of these areas by PCE may be responsible for visual deficits noted in humans. This model offers new methodological approaches for studying the adverse and therapeutic effects of psychostimulants on attention, and for the development of new pharmacological interventions. PMID:26379509

  16. Neural Plasticity: For Good and Bad

    NASA Astrophysics Data System (ADS)

    Møller, A. R.

    The brain's ability to change its organization and function is necessary for normal development of the nervous system and it makes it possible to adapt to changing demands but it can also cause disorders when going awry. This property, known as neural plasticity, is only evident when induced, very much like genes. Plastic changes may be programmed and providing a ``midcourse correction" during childhood development. If that is not executed in the normal way severe developmental disorders such as autism may results. Normal development of functions and anatomical organization of the brain and the spinal cord depend on appropriate sensory stimulation and motor activations. So-called enriched sensory environments have been shown to be beneficial for cognitive development and enriched acoustic environment may even slow the progression of age-related hearing loss. It is possible that the beneficial effect of physical exercise is achieved through activation of neural plasticity. The beneficial effect of training after trauma to the brain or spinal cord is mainly achieved through shifting functions from damaged brain area to other parts of the central nervous system and adapting these parts to take over the functions that are lost. This is accomplished through activation of neural plasticity. Plastic changes can also be harmful and cause symptoms and signs of disorders such as some forms of chronic pain (central neuropathic pain) and severe tinnitus. We will call such disorders ``plasticity disorders".

  17. Neural responsivity during soft drink intake, anticipation, and advertisement exposure in habitually consuming youth

    PubMed Central

    Burger, Kyle S.; Stice, Eric

    2014-01-01

    OBJECTIVE Although soft drinks are heavily advertised, widely consumed, and have been associated with obesity, little is understood regarding neural responsivity to soft drink intake, anticipated intake, and advertisements. METHODS Functional MRI was used to assess examine neural response to carbonated soft drink intake, anticipated intake and advertisement exposure as well as milkshake intake in 27 adolescents that varied on soft drink consumer status. RESULTS Intake and anticipated intake of carbonated Coke® activated regions implicated in gustatory, oral somatosensory, and reward processing, yet high-fat/sugar milkshake intake elicited greater activation in these regions versus Coke intake. Advertisements highlighting the Coke product vs. non-food control advertisements, but not the Coke logo, activated gustatory and visual brain regions. Habitual Coke consumers vs. non-consumers showed greater posterior cingulate responsivity to Coke logo ads, suggesting that the logo is a conditioned cue. Coke consumers exhibited less ventrolateral prefrontal cortex responsivity during anticipated Coke intake relative to non-consumers. CONCLUSIONS Results indicate that soft drinks activate reward and gustatory regions, but are less potent in activating these regions than high-fat/sugar beverages, and imply that habitual soft drink intake promotes hyper-responsivity of regions encoding salience/attention toward brand specific cues and hypo-responsivity of inhibitory regions while anticipating intake. PMID:23836764

  18. Imbalance in habitual versus goal directed neural systems during symptom provocation in obsessive-compulsive disorder.

    PubMed

    Banca, Paula; Voon, Valerie; Vestergaard, Martin D; Philipiak, Gregor; Almeida, Inês; Pocinho, Fernando; Relvas, João; Castelo-Branco, Miguel

    2015-03-01

    Intrusive thoughts and compulsive urges to perform stereotyped behaviours are typical symptoms of obsessive-compulsive disorder. Emerging evidence suggests a cognitive bias towards habit formation at the expense of goal-directed performance in obsessive-compulsive disorder. In this study, we test this hypothesis using a novel individualized ecologically valid symptom provocation design: a live provocation functional magnetic resonance imaging paradigm with synchronous video-recording of behavioural avoidance responses. By pairing symptom provocation with online avoidance responses on a trial-by-trial basis, we sought to investigate the neural mechanisms leading to the compulsive avoidance response. In keeping with the model of habit formation in obsessive-compulsive disorder, we hypothesized that this disorder would be associated with lower activity in regions implicated in goal-directed behaviours and higher activity in regions implicated in habitual behaviours. Fifteen patients with obsessive-compulsive disorder and 15 healthy control volunteers participated in this functional magnetic resonance imaging study. Online stimuli were individually tailored to achieve effective symptom provocation at neutral, intermediate and strong intensity levels. During the symptom provocation block, the participant could choose to reject or terminate the provoking stimuli resulting in cessation of the symptom provocation. We thus separately analysed the neural correlates of symptom provocation, the urge to avoid, rejection and relief. Strongly symptom-provoking conditions evoked a dichotomous pattern of deactivation/activation in patients, which was not observed either in control conditions or in healthy subjects: a deactivation of caudate-prefrontal circuits accompanied by hyperactivation of subthalamic nucleus/putaminal regions. This finding suggests a dissociation between regions engaged in goal-directed and habitual behaviours. The putaminal hyperactivity during patients

  19. Imbalance in habitual versus goal directed neural systems during symptom provocation in obsessive-compulsive disorder

    PubMed Central

    Banca, Paula; Voon, Valerie; Vestergaard, Martin D.; Philipiak, Gregor; Almeida, Inês; Pocinho, Fernando; Relvas, João

    2015-01-01

    Intrusive thoughts and compulsive urges to perform stereotyped behaviours are typical symptoms of obsessive-compulsive disorder. Emerging evidence suggests a cognitive bias towards habit formation at the expense of goal-directed performance in obsessive-compulsive disorder. In this study, we test this hypothesis using a novel individualized ecologically valid symptom provocation design: a live provocation functional magnetic resonance imaging paradigm with synchronous video-recording of behavioural avoidance responses. By pairing symptom provocation with online avoidance responses on a trial-by-trial basis, we sought to investigate the neural mechanisms leading to the compulsive avoidance response. In keeping with the model of habit formation in obsessive-compulsive disorder, we hypothesized that this disorder would be associated with lower activity in regions implicated in goal-directed behaviours and higher activity in regions implicated in habitual behaviours. Fifteen patients with obsessive-compulsive disorder and 15 healthy control volunteers participated in this functional magnetic resonance imaging study. Online stimuli were individually tailored to achieve effective symptom provocation at neutral, intermediate and strong intensity levels. During the symptom provocation block, the participant could choose to reject or terminate the provoking stimuli resulting in cessation of the symptom provocation. We thus separately analysed the neural correlates of symptom provocation, the urge to avoid, rejection and relief. Strongly symptom-provoking conditions evoked a dichotomous pattern of deactivation/activation in patients, which was not observed either in control conditions or in healthy subjects: a deactivation of caudate-prefrontal circuits accompanied by hyperactivation of subthalamic nucleus/putaminal regions. This finding suggests a dissociation between regions engaged in goal-directed and habitual behaviours. The putaminal hyperactivity during patients

  20. Neural plasticity in adults with amblyopia.

    PubMed Central

    Levi, D M; Polat, U

    1996-01-01

    Amblyopia is a neuronal abnormality of vision that is often considered irreversible in adults. We found strong and significant improvement of Vernier acuity in human adults with naturally occurring amblyopia following practice. Learning was strongest at the trained orientation and did not transfer to an untrained task (detection), but it did transfer partially to the untrained eye (primarily at the trained orientation). We conclude that this perceptual learning reflects alterations in early neural processes that are localized beyond the site of convergence of the two eyes. Our results suggest a significant degree of plasticity in the visual system of adults with amblyopia. PMID:8692904

  1. Neural Plasticity in Fathers of Human Infants

    PubMed Central

    Kim, Pilyoung; Rigo, Paola; Mayes, Linda C.; Feldman, Ruth; Leckman, James F.; Swain, James E

    2014-01-01

    Fathering plays an important role in infants’ socioemotional and cognitive development. Previous studies have identified brain regions that are important for parenting behavior in human mothers. However, the neural basis of parenting in human fathers is largely unexplored. In the current longitudinal study, we investigated structural changes in fathers’ brains during the first four months postpartum using voxel-based morphometry (VBM) analysis. Biological fathers (n=16) with full-term, healthy infants were scanned at 2–4 weeks postpartum (Time 1) and at 12–16 weeks postpartum (Time 2). Fathers exhibited increases in gray matter volume in several neural regions involved in parental motivation, including the hypothalamus, amygdala and striatum and lateral prefrontal cortex. On the other hand, fathers exhibited decreases in gray matter volume in the orbitofrontal cortex, posterior cingulate cortex and insula. The findings provide evidence for neural plasticity in fathers’ brains. We also discuss the distinct patterns of associations among neural changes, postpartum mood symptoms, and parenting behaviors among fathers. PMID:24958358

  2. Neural Plasticity Lessons from Disorders of Consciousness

    PubMed Central

    Demertzi, Athena; Schnakers, Caroline; Soddu, Andrea; Bruno, Marie-Aurélie; Gosseries, Olivia; Vanhaudenhuyse, Audrey; Laureys, Steven

    2010-01-01

    Communication and intentional behavior are supported by the brain's integrity at a structural and a functional level. When widespread loss of cerebral connectivity is brought about as a result of a severe brain injury, in many cases patients are not capable of conscious interactive behavior and are said to suffer from disorders of consciousness (e.g., coma, vegetative state/unresponsive wakefulness syndrome, minimally conscious states). This lesion paradigm has offered not only clinical insights, as how to improve diagnosis, prognosis, and treatment, but also put forward scientific opportunities to study the brain's plastic abilities. We here review interventional and observational studies performed in severely brain-injured patients with regards to recovery of consciousness. The study of the recovered conscious brain (spontaneous and/or after surgical or pharmacologic interventions), suggests a link between some specific brain areas and the capacity of the brain to sustain conscious experience, challenging at the same time the notion of fixed temporal boundaries in rehabilitative processes. Altered functional connectivity, cerebral structural reorganization as well as behavioral amelioration after invasive treatments will be discussed as the main indices for plasticity in these challenging patients. The study of patients with chronic disorders of consciousness may, thus, provide further insights not only at a clinical level (i.e., medical management and rehabilitation) but also from a scientific-theoretical perspective (i.e., the brain's plastic abilities and the pursuit of the neural correlate of consciousness). PMID:21833298

  3. Neural plasticity lessons from disorders of consciousness.

    PubMed

    Demertzi, Athena; Schnakers, Caroline; Soddu, Andrea; Bruno, Marie-Aurélie; Gosseries, Olivia; Vanhaudenhuyse, Audrey; Laureys, Steven

    2010-01-01

    Communication and intentional behavior are supported by the brain's integrity at a structural and a functional level. When widespread loss of cerebral connectivity is brought about as a result of a severe brain injury, in many cases patients are not capable of conscious interactive behavior and are said to suffer from disorders of consciousness (e.g., coma, vegetative state/unresponsive wakefulness syndrome, minimally conscious states). This lesion paradigm has offered not only clinical insights, as how to improve diagnosis, prognosis, and treatment, but also put forward scientific opportunities to study the brain's plastic abilities. We here review interventional and observational studies performed in severely brain-injured patients with regards to recovery of consciousness. The study of the recovered conscious brain (spontaneous and/or after surgical or pharmacologic interventions), suggests a link between some specific brain areas and the capacity of the brain to sustain conscious experience, challenging at the same time the notion of fixed temporal boundaries in rehabilitative processes. Altered functional connectivity, cerebral structural reorganization as well as behavioral amelioration after invasive treatments will be discussed as the main indices for plasticity in these challenging patients. The study of patients with chronic disorders of consciousness may, thus, provide further insights not only at a clinical level (i.e., medical management and rehabilitation) but also from a scientific-theoretical perspective (i.e., the brain's plastic abilities and the pursuit of the neural correlate of consciousness). PMID:21833298

  4. Activity-dependent neural plasticity from bench to bedside.

    PubMed

    Ganguly, Karunesh; Poo, Mu-Ming

    2013-10-30

    Much progress has been made in understanding how behavioral experience and neural activity can modify the structure and function of neural circuits during development and in the adult brain. Studies of physiological and molecular mechanisms underlying activity-dependent plasticity in animal models have suggested potential therapeutic approaches for a wide range of brain disorders in humans. Physiological and electrical stimulations as well as plasticity-modifying molecular agents may facilitate functional recovery by selectively enhancing existing neural circuits or promoting the formation of new functional circuits. Here, we review the advances in basic studies of neural plasticity mechanisms in developing and adult nervous systems and current clinical treatments that harness neural plasticity, and we offer perspectives on future development of plasticity-based therapy. PMID:24183023

  5. Early life nutrition and neural plasticity

    PubMed Central

    Georgieff, Michael K.; Brunette, Katya E; Tran, Phu V

    2015-01-01

    The human brain undergoes a remarkable transformation during fetal life and the first postnatal years from a relatively undifferentiated but pluripotent organ to a highly specified and organized one. The outcome of this developmental maturation is highly dependent on a sequence of environmental exposures that can have either positive or negative influences on the ultimate plasticity of the adult brain. Many environmental exposures are beyond the control of the individual, but nutrition is not. An ever-increasing amount of research demonstrates that nutrition not only shapes the brain and affects its function during development, but that several nutrients early in life have profound and long-lasting effects on the brain. Nutrients have been shown to alter opening and closing of critical and sensitive periods of particular brain regions. This paper discusses the roles that various nutrients play in shaping the developing brain, concentrating specifically on recently explicated biological mechanisms by which particularly salient nutrients influence childhood and adult neural plasticity. PMID:25997762

  6. Neural Plasticity and Neurorehabilitation: Teaching the New Brain Old Tricks

    ERIC Educational Resources Information Center

    Kleim, Jeffrey A.

    2011-01-01

    Following brain injury or disease there are widespread biochemical, anatomical and physiological changes that result in what might be considered a new, very different brain. This adapted brain is forced to reacquire behaviors lost as a result of the injury or disease and relies on neural plasticity within the residual neural circuits. The same…

  7. Short-term synaptic plasticity and heterogeneity in neural systems

    NASA Astrophysics Data System (ADS)

    Mejias, J. F.; Kappen, H. J.; Longtin, A.; Torres, J. J.

    2013-01-01

    We review some recent results on neural dynamics and information processing which arise when considering several biophysical factors of interest, in particular, short-term synaptic plasticity and neural heterogeneity. The inclusion of short-term synaptic plasticity leads to enhanced long-term memory capacities, a higher robustness of memory to noise, and irregularity in the duration of the so-called up cortical states. On the other hand, considering some level of neural heterogeneity in neuron models allows neural systems to optimize information transmission in rate coding and temporal coding, two strategies commonly used by neurons to codify information in many brain areas. In all these studies, analytical approximations can be made to explain the underlying dynamics of these neural systems.

  8. Shaping the learning curve: epigenetic dynamics in neural plasticity

    PubMed Central

    Bronfman, Zohar Z.; Ginsburg, Simona; Jablonka, Eva

    2014-01-01

    A key characteristic of learning and neural plasticity is state-dependent acquisition dynamics reflected by the non-linear learning curve that links increase in learning with practice. Here we propose that the manner by which epigenetic states of individual cells change during learning contributes to the shape of the neural and behavioral learning curve. We base our suggestion on recent studies showing that epigenetic mechanisms such as DNA methylation, histone acetylation, and RNA-mediated gene regulation are intimately involved in the establishment and maintenance of long-term neural plasticity, reflecting specific learning-histories and influencing future learning. Our model, which is the first to suggest a dynamic molecular account of the shape of the learning curve, leads to several testable predictions regarding the link between epigenetic dynamics at the promoter, gene-network, and neural-network levels. This perspective opens up new avenues for therapeutic interventions in neurological pathologies. PMID:25071483

  9. Neural Circuitry and Plasticity Mechanisms Underlying Delay Eyeblink Conditioning

    ERIC Educational Resources Information Center

    Freeman, John H.; Steinmetz, Adam B.

    2011-01-01

    Pavlovian eyeblink conditioning has been used extensively as a model system for examining the neural mechanisms underlying associative learning. Delay eyeblink conditioning depends on the intermediate cerebellum ipsilateral to the conditioned eye. Evidence favors a two-site plasticity model within the cerebellum with long-term depression of…

  10. Models of Neural Plasticity and Classroom Practice.

    ERIC Educational Resources Information Center

    Brown, Dawn L.; Wheatley, Grayson H.

    The purpose of this paper is to explore the relationship between constructivism and neural organization. Support is given for a constructivist epistemology in current brain theory. A brief description of constructivism is provided, followed by the implication of this set of beliefs for viewing humans as self-organizing systems. What has been…

  11. Neural Plasticity in Common Forms of Chronic Headaches

    PubMed Central

    Lai, Tzu-Hsien; Protsenko, Ekaterina; Cheng, Yu-Chen; Loggia, Marco L.; Coppola, Gianluca; Chen, Wei-Ta

    2015-01-01

    Headaches are universal experiences and among the most common disorders. While headache may be physiological in the acute setting, it can become a pathological and persistent condition. The mechanisms underlying the transition from episodic to chronic pain have been the subject of intense study. Using physiological and imaging methods, researchers have identified a number of different forms of neural plasticity associated with migraine and other headaches, including peripheral and central sensitization, and alterations in the endogenous mechanisms of pain modulation. While these changes have been proposed to contribute to headache and pain chronification, some findings are likely the results of repetitive noxious stimulation, such as atrophy of brain areas involved in pain perception and modulation. In this review, we provide a narrative overview of recent advances on the neuroimaging, electrophysiological and genetic aspects of neural plasticity associated with the most common forms of chronic headaches, including migraine, cluster headache, tension-type headache, and medication overuse headache. PMID:26366304

  12. Learning-induced neural plasticity of speech processing before birth

    PubMed Central

    Partanen, Eino; Kujala, Teija; Näätänen, Risto; Liitola, Auli; Sambeth, Anke; Huotilainen, Minna

    2013-01-01

    Learning, the foundation of adaptive and intelligent behavior, is based on plastic changes in neural assemblies, reflected by the modulation of electric brain responses. In infancy, auditory learning implicates the formation and strengthening of neural long-term memory traces, improving discrimination skills, in particular those forming the prerequisites for speech perception and understanding. Although previous behavioral observations show that newborns react differentially to unfamiliar sounds vs. familiar sound material that they were exposed to as fetuses, the neural basis of fetal learning has not thus far been investigated. Here we demonstrate direct neural correlates of human fetal learning of speech-like auditory stimuli. We presented variants of words to fetuses; unlike infants with no exposure to these stimuli, the exposed fetuses showed enhanced brain activity (mismatch responses) in response to pitch changes for the trained variants after birth. Furthermore, a significant correlation existed between the amount of prenatal exposure and brain activity, with greater activity being associated with a higher amount of prenatal speech exposure. Moreover, the learning effect was generalized to other types of similar speech sounds not included in the training material. Consequently, our results indicate neural commitment specifically tuned to the speech features heard before birth and their memory representations. PMID:23980148

  13. Habitual Alcohol Seeking: Neural Bases and Possible Relations to Alcohol Use Disorders.

    PubMed

    Corbit, Laura H; Janak, Patricia H

    2016-07-01

    Loss of flexible control over alcohol use may contribute to the development of alcohol use disorders. An increased contribution of response habits to alcohol-related behaviors may help explain this loss of control. Focusing on data from outcome devaluation and Pavlovian-instrumental transfer procedures, we review evidence for loss of goal-directed control over alcohol seeking and consumption drawing from both preclinical findings and clinical data where they exist. Over the course of extended alcohol self-administration and exposure, the performance of alcohol-seeking responses becomes less sensitive to reduction in the value of alcohol and more vulnerable to the influences of alcohol-predictive stimuli. These behavioral changes are accompanied by a shift in the corticostriatal circuits that control responding from circuits centered on the dorsomedial to those centered on the dorsolateral striatum. These changes in behavioral and neural control could help explain failures to abstain from alcohol despite intention to do so. Understanding and ultimately ameliorating these changes will aid development of more effective treatment interventions. PMID:27223341

  14. Using sensor habituation in mobile robots to reduce oscillatory movements in narrow corridors.

    PubMed

    Chang, Carolina

    2005-11-01

    Habituation is a form of nonassociative learning observed in a variety of species of animals. Arguably, it is the simplest form of learning. Nonetheless, the ability to habituate to certain stimuli implies plastic neural systems and adaptive behaviors. This paper describes how computational models of habituation can be applied to real robots. In particular, we discuss the problem of the oscillatory movements observed when a Khepera robot navigates through narrow hallways using a biologically inspired neurocontroller. Results show that habituation to the proximity of the walls can lead to smoother navigation. Habituation to sensory stimulation to the sides of the robot does not interfere with the robot's ability to turn at dead ends and to avoid obstacles outside the hallway. This paper shows that simple biological mechanisms of learning can be adapted to achieve better performance in real mobile robots. PMID:16342498

  15. Vertebrate Neural Stem Cells: Development, Plasticity, and Regeneration.

    PubMed

    Shimazaki, Takuya

    2016-03-25

    Natural recovery from disease and damage in the adult mammalian central nervous system (CNS) is limited compared with that in lower vertebrate species, including fish and salamanders. Species-specific differences in the plasticity of the CNS reflect these differences in regenerative capacity. Despite numerous extensive studies in the field of CNS regeneration, our understanding of the molecular mechanisms determining the regenerative capacity of the CNS is still relatively poor. The discovery of adult neural stem cells (aNSCs) in mammals, including humans, in the early 1990s has opened up new possibilities for the treatment of CNS disorders via self-regeneration through the mobilization of these cells. However, we now know that aNSCs in mammals are not plastic enough to induce significant regeneration. In contrast, aNSCs in some regenerative species have been found to be as highly plastic as early embryonic neural stem cells (NSCs). We must expand our knowledge of NSCs and of regenerative processes in lower vertebrates in an effort to develop effective regenerative treatments for damaged CNS in humans. PMID:26853878

  16. Neural Plastic Effects of Cognitive Training on Aging Brain

    PubMed Central

    Leung, Natalie T. Y.; Tam, Helena M. K.; Chu, Leung W.; Kwok, Timothy C. Y.; Chan, Felix; Lam, Linda C. W.; Woo, Jean; Lee, Tatia M. C.

    2015-01-01

    Increasing research has evidenced that our brain retains a capacity to change in response to experience until late adulthood. This implies that cognitive training can possibly ameliorate age-associated cognitive decline by inducing training-specific neural plastic changes at both neural and behavioral levels. This longitudinal study examined the behavioral effects of a systematic thirteen-week cognitive training program on attention and working memory of older adults who were at risk of cognitive decline. These older adults were randomly assigned to the Cognitive Training Group (n = 109) and the Active Control Group (n = 100). Findings clearly indicated that training induced improvement in auditory and visual-spatial attention and working memory. The training effect was specific to the experience provided because no significant difference in verbal and visual-spatial memory between the two groups was observed. This pattern of findings is consistent with the prediction and the principle of experience-dependent neuroplasticity. Findings of our study provided further support to the notion that the neural plastic potential continues until older age. The baseline cognitive status did not correlate with pre- versus posttraining changes to any cognitive variables studied, suggesting that the initial cognitive status may not limit the neuroplastic potential of the brain at an old age. PMID:26417460

  17. Neurogenetic approaches to habituation and dishabituation in Drosophila.

    PubMed

    Engel, Jeff E; Wu, Chun-Fang

    2009-09-01

    We review work in the major model systems for habituation in Drosophila melanogaster, encompassing several sensory modalities and behavioral contexts: visual (giant fiber escape response, landing response); chemical (proboscis extension reflex, olfactory jump response, locomotory startle response, odor-induced leg response, experience-dependent courtship modification); electric (shock avoidance); and mechanical (leg resistance reflex, cleaning reflex). Each model system shows several of Thompson and Spencer's [Thompson, R. F., & Spencer, W. A. (1966). Habituation: A model phenomenon for the study of neuronal substrates of behavior. Psychological Review, 73, 16-43] parametric criteria for habituation: spontaneous recovery and dishabituation have been described in almost all of them and dependence of habituation upon stimulus frequency and stimulus intensity in the majority. Stimulus generalization (and conversely, the delineation of stimulus specificity) has given insights into the localization of habituation or the neural architecture underlying sensory processing. The strength of Drosophila for studying habituation is the range of genetic approaches available. Mutations have been used to modify specific neuroanatomical structures, ion channels, elements of synaptic transmission, and second-messenger pathways. rutabaga and dunce, genes of the cAMP signal pathway that have been studied most often in the reviewed experiments, have also been implicated in synaptic plasticity and associative conditioning in Drosophila and other species including mammals. The use of the Gal4/UAS system for targeting gene expression has enabled genetic perturbation of defined sets of neurons. One clear lesson is that a gene may affect habituation differently in different behaviors, depending on the expression, processing, and localization of the gene product in specific circuits. Mutations of specific genes not only provide links between physiology and behavior in the same circuit, but

  18. Habitual vs Non-Habitual Manual Actions: An ERP Study on Overt Movement Execution

    PubMed Central

    Westerholz, Jan; Schack, Thomas; Schütz, Christoph; Koester, Dirk

    2014-01-01

    This study explored the neurophysiological mechanisms underlying the planning and execution of an overt goal-related handle rotation task. More specifically, we studied the neural basis of motor actions concerning the influence of the grasp choice. The aim of the present study was to differentiate cerebral activity between grips executed in a habitual and a non-habitual mode, and between specified and free grip choices. To our knowledge, this is the first study to differentiate cerebral activity underlying overt goal-related actions executed with a focus on the habitual mode. In a handle rotation task, participants had to use thumb-toward (habitual) or thumb-away (non-habitual) grips to rotate a handle to a given target position. Reaction and reach times were shorter for the habitual compared to the non-habitual mode indicating that the habitual mode requires less cognitive processing effort than the non-habitual mode. Neural processes for action execution (measured by event-related potentials (ERPs)) differed between habitual and non-habitual conditions. We found differential activity between habitual and non-habitual conditions in left and right frontal areas from −600 to 200 ms time-locked to reaching the target position. No differential neural activity could be traced for the specification of the grip. The results suggested that the frontal negativity reflected increased difficulty in movement precision control in the non-habitual mode compared to the habitual mode during the homing in phase of grasp and rotation actions. PMID:24691654

  19. The Effects of Leptin Replacement on Neural Plasticity

    PubMed Central

    Paz-Filho, Gilberto J.

    2016-01-01

    Leptin, an adipokine synthesized and secreted mainly by the adipose tissue, has multiple effects on the regulation of food intake, energy expenditure, and metabolism. Its recently-approved analogue, metreleptin, has been evaluated in clinical trials for the treatment of patients with leptin deficiency due to mutations in the leptin gene, lipodystrophy syndromes, and hypothalamic amenorrhea. In such patients, leptin replacement therapy has led to changes in brain structure and function in intra- and extrahypothalamic areas, including the hippocampus. Furthermore, in one of those patients, improvements in neurocognitive development have been observed. In addition to this evidence linking leptin to neural plasticity and function, observational studies evaluating leptin-sufficient humans have also demonstrated direct correlation between blood leptin levels and brain volume and inverse associations between circulating leptin and risk for the development of dementia. This review summarizes the evidence in the literature on the role of leptin in neural plasticity (in leptin-deficient and in leptin-sufficient individuals) and its effects on synaptic activity, glutamate receptor trafficking, neuronal morphology, neuronal development and survival, and microglial function. PMID:26881138

  20. Rapid neural circuit switching mediated by synaptic plasticity during neural morphallactic regeneration.

    PubMed

    Lybrand, Zane R; Zoran, Mark J

    2012-09-01

    The aquatic oligochaete, Lumbriculus variegatus (Lumbriculidae), undergoes a rapid regenerative transformation of its neural circuits following body fragmentation. This type of nervous system plasticity, called neural morphallaxis, involves the remodeling of the giant fiber pathways that mediate rapid head and tail withdrawal behaviors. Extra- and intracellular electrophysiological recordings demonstrated that changes in cellular properties and synaptic connections underlie neurobehavioral plasticity during morphallaxis. Sensory-to-giant interneuron connections, undetectable prior to body injury, emerged within hours of segment amputation. The appearance of functional synaptic transmission was followed by interneuron activation, coupling of giant fiber spiking to motor outputs and overt segmental shortening. The onset of morphallactic plasticity varied along the body axis and emerged more rapidly in segments closer to regions of sensory field overlap between the two giant fiber pathways. The medial and lateral giant fibers were simultaneously activated during a transient phase of network remodeling. Thus, synaptic plasticity at sensory-to-giant interneuron connections mediates escape circuit morphallaxis in this regenerating annelid worm. PMID:22021133

  1. Spike timing analysis in neural networks with unsupervised synaptic plasticity

    NASA Astrophysics Data System (ADS)

    Mizusaki, B. E. P.; Agnes, E. J.; Brunnet, L. G.; Erichsen, R., Jr.

    2013-01-01

    The synaptic plasticity rules that sculpt a neural network architecture are key elements to understand cortical processing, as they may explain the emergence of stable, functional activity, while avoiding runaway excitation. For an associative memory framework, they should be built in a way as to enable the network to reproduce a robust spatio-temporal trajectory in response to an external stimulus. Still, how these rules may be implemented in recurrent networks and the way they relate to their capacity of pattern recognition remains unclear. We studied the effects of three phenomenological unsupervised rules in sparsely connected recurrent networks for associative memory: spike-timing-dependent-plasticity, short-term-plasticity and an homeostatic scaling. The system stability is monitored during the learning process of the network, as the mean firing rate converges to a value determined by the homeostatic scaling. Afterwards, it is possible to measure the recovery efficiency of the activity following each initial stimulus. This is evaluated by a measure of the correlation between spike fire timings, and we analysed the full memory separation capacity and limitations of this system.

  2. Mice lacking the adenosine A1 receptor have normal spatial learning and plasticity in the CA1 region of the hippocampus, but they habituate more slowly.

    PubMed

    Giménez-Llort, Lydia; Masino, Susan A; Diao, Lihong; Fernández-Teruel, Alberto; Tobeña, Adolf; Halldner, Linda; Fredholm, Bertil B

    2005-07-01

    Using mice with a targeted disruption of the adenosine A1 receptor (A1R), we examined the role of A1Rs in hippocampal long-term potentiation (LTP), long-term depression (LTD), and memory formation. Recordings from the Shaffer collateral-CA1 pathway of hippocampal slices from adult mice showed no differences between theta burst and tetanic stimulation-induced LTP in adenosine A1 receptor knockout (A1R-/-), heterozygote (A1R+/-), and wildtype (A1R+/+) mice. However, paired pulse facilitation was impaired significantly in A1R-/- slices as compared to A1R+/+ slices. LTD in the CA1 region was unaffected by the genetic manipulation. The three genotypes showed similar memory acquisition patterns when assessed for spatial reference and working memory in the Morris water maze tasks at 9 months of age. However, 10 months later A1R-/- mice showed some deficits in the 6-arm radial tunnel maze test. The latter appeared, however, not due to memory deficits but to decreased habituation to the test environment. Taken together, we observe normal spatial learning and memory and hippocampal CA1 synaptic plasticity in adult adenosine A1R knockout mice, but find modifications in arousal-related processes, including habituation, in this knockout model. PMID:15858837

  3. NEURAL PLASTICITY, HUMAN GENETICS, AND RISK FOR ALCOHOL DEPENDENCE

    PubMed Central

    Hill, Shirley Y.

    2013-01-01

    Opportunities for advances in the neurobiology of alcohol dependence have been facilitated by the development of sophisticated neurophysiological and neuroimaging techniques that allow us to have a window on developmental changes in brain structure and function. The search for genes that may increase susceptibility to alcohol dependence has been greatly facilitated by the recognition that intermediate phenotypes, sometimes referred to as endophenotypes. may be closer to the genetic variation than is the more complex alcohol dependence phenotype. This chapter will review the evidence that the brain is highly plastic, exhibiting major postnatal changes, especially during adolescence, in neural circuits that appear to influence addiction susceptibility. This chapter will suggest that heritable aspects of brain structure and function that are seen developmentally may be an important endophenotypic characteristic associated with familial risk for developing alcohol dependence. Finally, a review of studies showing associations between brain structural and functional characteristics and specific genes will be offered. PMID:20813240

  4. Remodeling myelination: implications for mechanisms of neural plasticity

    PubMed Central

    Chang, Kae-Jiun; Redmond, Stephanie A; Chan, Jonah R

    2016-01-01

    One of the most significant paradigm shifts in membrane remodeling is the emerging view that membrane transformation is not exclusively controlled by cytoskeletal rearrangement, but also by biophysical constraints, adhesive forces, membrane curvature and compaction. One of the most exquisite examples of membrane remodeling is myelination. The advent of myelin was instrumental in advancing the nervous system during vertebrate evolution. With more rapid and efficient communication between neurons, faster and more complex computations could be performed in a given time and space. Our knowledge of how myelin-forming oligodendrocytes select and wrap axons has been limited by insufficient spatial and temporal resolution. By virtue of recent technological advances, progress has clarified longstanding controversies in the field. Here we review insights into myelination, from target selection to axon wrapping and membrane compaction, and discuss how understanding these processes has unexpectedly opened new avenues of insight into myelination-centered mechanisms of neural plasticity. PMID:26814588

  5. On Aerobic Exercise and Behavioral and Neural Plasticity

    PubMed Central

    Swain, Rodney A.; Berggren, Kiersten L.; Kerr, Abigail L.; Patel, Ami; Peplinski, Caitlin; Sikorski, Angela M.

    2012-01-01

    Aerobic exercise promotes rapid and profound alterations in the brain. Depending upon the pattern and duration of exercise, these changes in the brain may extend beyond traditional motor areas to regions and structures normally linked to learning, cognition, and emotion. Exercise-induced alterations may include changes in blood flow, hormone and growth factor release, receptor expression, angiogenesis, apoptosis, neurogenesis, and synaptogenesis. Together, we believe that these changes underlie elevations of mood and prompt the heightened behavioral plasticity commonly observed following adoption of a chronic exercise regimen. In the following paper, we will explore both the psychological and psychobiological literatures relating to exercise effects on brain in both human and non-human animals and will attempt to link plastic changes in these neural structures to modifications in learned behavior and emotional expression. In addition, we will explore the therapeutic potential of exercise given recent reports that aerobic exercise may serve as a neuroprotectant and can also slow cognitive decline during normal and pathological aging. PMID:24961267

  6. Auditory Training: Evidence for Neural Plasticity in Older Adults

    PubMed Central

    Anderson, Samira; Kraus, Nina

    2014-01-01

    Improvements in digital amplification, cochlear implants, and other innovations have extended the potential for improving hearing function; yet, there remains a need for further hearing improvement in challenging listening situations, such as when trying to understand speech in noise or when listening to music. Here, we review evidence from animal and human models of plasticity in the brain’s ability to process speech and other meaningful stimuli. We considered studies targeting populations of younger through older adults, emphasizing studies that have employed randomized controlled designs and have made connections between neural and behavioral changes. Overall results indicate that the brain remains malleable through older adulthood, provided that treatment algorithms have been modified to allow for changes in learning with age. Improvements in speech-in-noise perception and cognition function accompany neural changes in auditory processing. The training-related improvements noted across studies support the need to consider auditory training strategies in the management of individuals who express concerns about hearing in difficult listening situations. Given evidence from studies engaging the brain’s reward centers, future research should consider how these centers can be naturally activated during training. PMID:25485037

  7. Neural stem cells: plasticity and their transdifferentiation potential.

    PubMed

    Vescovi, Angelo; Gritti, Angela; Cossu, Giulio; Galli, Rossella

    2002-01-01

    The presence of resident stem cells in adult tissues is of fundamental importance for the maintenance of their structural and functional integrity. In fact, throughout life, somatic stem cells attend to the critical function of substituting terminally differentiated cells lost to physiological turnover, injury or disease. Thence, one of the basic dogmata in tissue biology holds that the differentiation potential of an adult stem cell is restricted to the generation of the mature cell lineages found in the tissue to which the stem cell belongs. A plethora of recent evidences from many groups, including ours, is now providing evidence that adult stem cells may possess a broader differentiation repertoire than expected and that their fate potential may not be as tissue specific as once thought. The initial example of an unforeseen, trans-germ layer plasticity - that seems now to emerge as a prototypic functional trait of various somatic stem cells of different origin - has come from the reported awakening of a latent hemopoietic developmental capacity in stem cells isolated from the adult mammalian brain following their transplantation into sub-lethally irradiated mice. More recently, it has been shown that adult neural stem cells can differentiate into a wide array of bodily cells of different origin when injected into the blastocyst and into myogenic cells when transplanted into the adult regenerating skeletal muscle. Moreover, bone marrow stem cells can now give rise to skeletal muscle, hepatic and brain cells, whereas muscle precursors can generate blood cells. In this article, we review some of the basic notions regarding the functional properties of the adult neural stem cells and discuss findings in the expanding area of trans-germ layer conversion, with emphasis on the neural stem cell. PMID:12021492

  8. Rehabilitation with Poststroke Motor Recovery: A Review with a Focus on Neural Plasticity

    PubMed Central

    Takeuchi, Naoyuki; Izumi, Shin-Ichi

    2013-01-01

    Motor recovery after stroke is related to neural plasticity, which involves developing new neuronal interconnections, acquiring new functions, and compensating for impairment. However, neural plasticity is impaired in the stroke-affected hemisphere. Therefore, it is important that motor recovery therapies facilitate neural plasticity to compensate for functional loss. Stroke rehabilitation programs should include meaningful, repetitive, intensive, and task-specific movement training in an enriched environment to promote neural plasticity and motor recovery. Various novel stroke rehabilitation techniques for motor recovery have been developed based on basic science and clinical studies of neural plasticity. However, the effectiveness of rehabilitative interventions among patients with stroke varies widely because the mechanisms underlying motor recovery are heterogeneous. Neurophysiological and neuroimaging studies have been developed to evaluate the heterogeneity of mechanisms underlying motor recovery for effective rehabilitation interventions after stroke. Here, we review novel stroke rehabilitation techniques associated with neural plasticity and discuss individualized strategies to identify appropriate therapeutic goals, prevent maladaptive plasticity, and maximize functional gain in patients with stroke. PMID:23738231

  9. Self-control of chaos in neural circuits with plastic electrical synapses

    NASA Astrophysics Data System (ADS)

    Zhigulin, V. P.; Rabinovich, M. I.

    2004-10-01

    Two kinds of connections are known to exist in neural circuits: electrical (also called gap junctions) and chemical. Whereas chemical synapses are known to be plastic (i. e., modifiable), but slow, electrical transmission through gap junctions is not modifiable, but is very fast. We suggest the new artificial synapse that combines the best properties of both: the fast reaction of a gap junction and the plasticity of a chemical synapse. Such a plastic electrical synapse can be used in hybrid neural circuits and for the development of neural prosthetics, i.e., implanted devices that can interact with the real nervous system. Based on the computer modelling we show that such a plastic electrical synapse regularizes chaos in the minimal neural circuit consisting of two chaotic bursting neurons.

  10. Translating Principles of Neural Plasticity into Research on Speech Motor Control Recovery and Rehabilitation

    ERIC Educational Resources Information Center

    Ludlow, Christy L.; Hoit, Jeannette; Kent, Raymond; Ramig, Lorraine O.; Shrivastav, Rahul; Strand, Edythe; Yorkston, Kathryn; Sapienza, Christine M.

    2008-01-01

    Purpose: To review the principles of neural plasticity and make recommendations for research on the neural bases for rehabilitation of neurogenic speech disorders. Method: A working group in speech motor control and disorders developed this report, which examines the potential relevance of basic research on the brain mechanisms involved in neural…

  11. Neuron-Glia Interactions in Neural Plasticity: Contributions of Neural Extracellular Matrix and Perineuronal Nets

    PubMed Central

    Dzyubenko, Egor; Gottschling, Christine

    2016-01-01

    Synapses are specialized structures that mediate rapid and efficient signal transmission between neurons and are surrounded by glial cells. Astrocytes develop an intimate association with synapses in the central nervous system (CNS) and contribute to the regulation of ion and neurotransmitter concentrations. Together with neurons, they shape intercellular space to provide a stable milieu for neuronal activity. Extracellular matrix (ECM) components are synthesized by both neurons and astrocytes and play an important role in the formation, maintenance, and function of synapses in the CNS. The components of the ECM have been detected near glial processes, which abut onto the CNS synaptic unit, where they are part of the specialized macromolecular assemblies, termed perineuronal nets (PNNs). PNNs have originally been discovered by Golgi and represent a molecular scaffold deposited in the interface between the astrocyte and subsets of neurons in the vicinity of the synapse. Recent reports strongly suggest that PNNs are tightly involved in the regulation of synaptic plasticity. Moreover, several studies have implicated PNNs and the neural ECM in neuropsychiatric diseases. Here, we highlight current concepts relating to neural ECM and PNNs and describe an in vitro approach that allows for the investigation of ECM functions for synaptogenesis. PMID:26881114

  12. Using brain-computer interfaces to induce neural plasticity and restore function

    NASA Astrophysics Data System (ADS)

    Grosse-Wentrup, Moritz; Mattia, Donatella; Oweiss, Karim

    2011-04-01

    Analyzing neural signals and providing feedback in realtime is one of the core characteristics of a brain-computer interface (BCI). As this feature may be employed to induce neural plasticity, utilizing BCI technology for therapeutic purposes is increasingly gaining popularity in the BCI community. In this paper, we discuss the state-of-the-art of research on this topic, address the principles of and challenges in inducing neural plasticity by means of a BCI, and delineate the problems of study design and outcome evaluation arising in this context. We conclude with a list of open questions and recommendations for future research in this field.

  13. A framework for plasticity implementation on the SpiNNaker neural architecture

    PubMed Central

    Galluppi, Francesco; Lagorce, Xavier; Stromatias, Evangelos; Pfeiffer, Michael; Plana, Luis A.; Furber, Steve B.; Benosman, Ryad B.

    2015-01-01

    Many of the precise biological mechanisms of synaptic plasticity remain elusive, but simulations of neural networks have greatly enhanced our understanding of how specific global functions arise from the massively parallel computation of neurons and local Hebbian or spike-timing dependent plasticity rules. For simulating large portions of neural tissue, this has created an increasingly strong need for large scale simulations of plastic neural networks on special purpose hardware platforms, because synaptic transmissions and updates are badly matched to computing style supported by current architectures. Because of the great diversity of biological plasticity phenomena and the corresponding diversity of models, there is a great need for testing various hypotheses about plasticity before committing to one hardware implementation. Here we present a novel framework for investigating different plasticity approaches on the SpiNNaker distributed digital neural simulation platform. The key innovation of the proposed architecture is to exploit the reconfigurability of the ARM processors inside SpiNNaker, dedicating a subset of them exclusively to process synaptic plasticity updates, while the rest perform the usual neural and synaptic simulations. We demonstrate the flexibility of the proposed approach by showing the implementation of a variety of spike- and rate-based learning rules, including standard Spike-Timing dependent plasticity (STDP), voltage-dependent STDP, and the rate-based BCM rule. We analyze their performance and validate them by running classical learning experiments in real time on a 4-chip SpiNNaker board. The result is an efficient, modular, flexible and scalable framework, which provides a valuable tool for the fast and easy exploration of learning models of very different kinds on the parallel and reconfigurable SpiNNaker system. PMID:25653580

  14. A framework for plasticity implementation on the SpiNNaker neural architecture.

    PubMed

    Galluppi, Francesco; Lagorce, Xavier; Stromatias, Evangelos; Pfeiffer, Michael; Plana, Luis A; Furber, Steve B; Benosman, Ryad B

    2014-01-01

    Many of the precise biological mechanisms of synaptic plasticity remain elusive, but simulations of neural networks have greatly enhanced our understanding of how specific global functions arise from the massively parallel computation of neurons and local Hebbian or spike-timing dependent plasticity rules. For simulating large portions of neural tissue, this has created an increasingly strong need for large scale simulations of plastic neural networks on special purpose hardware platforms, because synaptic transmissions and updates are badly matched to computing style supported by current architectures. Because of the great diversity of biological plasticity phenomena and the corresponding diversity of models, there is a great need for testing various hypotheses about plasticity before committing to one hardware implementation. Here we present a novel framework for investigating different plasticity approaches on the SpiNNaker distributed digital neural simulation platform. The key innovation of the proposed architecture is to exploit the reconfigurability of the ARM processors inside SpiNNaker, dedicating a subset of them exclusively to process synaptic plasticity updates, while the rest perform the usual neural and synaptic simulations. We demonstrate the flexibility of the proposed approach by showing the implementation of a variety of spike- and rate-based learning rules, including standard Spike-Timing dependent plasticity (STDP), voltage-dependent STDP, and the rate-based BCM rule. We analyze their performance and validate them by running classical learning experiments in real time on a 4-chip SpiNNaker board. The result is an efficient, modular, flexible and scalable framework, which provides a valuable tool for the fast and easy exploration of learning models of very different kinds on the parallel and reconfigurable SpiNNaker system. PMID:25653580

  15. Habituation of reinforcer effectiveness.

    PubMed

    Lloyd, David R; Medina, Douglas J; Hawk, Larry W; Fosco, Whitney D; Richards, Jerry B

    2014-01-01

    In this paper we propose an integrative model of habituation of reinforcer effectiveness (HRE) that links behavioral- and neural-based explanations of reinforcement. We argue that HRE is a fundamental property of reinforcing stimuli. Most reinforcement models implicitly suggest that the effectiveness of a reinforcer is stable across repeated presentations. In contrast, an HRE approach predicts decreased effectiveness due to repeated presentation. We argue that repeated presentation of reinforcing stimuli decreases their effectiveness and that these decreases are described by the behavioral characteristics of habituation (McSweeney and Murphy, 2009; Rankin etal., 2009). We describe a neural model that postulates a positive association between dopamine neurotransmission and HRE. We present evidence that stimulant drugs, which artificially increase dopamine neurotransmission, disrupt (slow) normally occurring HRE and also provide evidence that stimulant drugs have differential effects on operant responding maintained by reinforcers with rapid vs. slow HRE rates. We hypothesize that abnormal HRE due to genetic and/or environmental factors may underlie some behavioral disorders. For example, recent research indicates that slow-HRE is predictive of obesity. In contrast ADHD may reflect "accelerated-HRE." Consideration of HRE is important for the development of effective reinforcement-based treatments. Finally, we point out that most of the reinforcing stimuli that regulate daily behavior are non-consumable environmental/social reinforcers which have rapid-HRE. The almost exclusive use of consumable reinforcers with slow-HRE in pre-clinical studies with animals may have caused the importance of HRE to be overlooked. Further study of reinforcing stimuli with rapid-HRE is needed in order to understand how habituation and reinforcement interact and regulate behavior. PMID:24409128

  16. Translating Principles of Neural Plasticity into Research on Speech Motor Control Recovery and Rehabilitation

    PubMed Central

    Ludlow, Christy L.; Hoit, Jeannette; Kent, Raymond; Ramig, Lorraine O.; Shrivastav, Rahul; Strand, Edythe; Yorkston, Kathryn; Sapienza, Christine

    2008-01-01

    Purpose To review the principles of neural plasticity and make recommendations for research on the neural bases for rehabilitation of neurogenic speech disorders. Method A working group in speech motor control and disorders developed this report, which examines the potential relevance of basic research on the brain mechanisms involved in neural plasticity and discusses possible similarities and differences for application to speech motor control disorders. The possible involvement of neural plasticity in changes in speech production in normalcy, development, aging, and neurological diseases and disorders was considered. This report focuses on the appropriate use of functional and structural neuroimaging and the design of feasibility studies aimed at understanding how brain mechanisms are altered by environmental manipulations such as training and stimulation and how these changes might enhance the future development of rehabilitative methods for persons with speech motor control disorders. Conclusions Increased collaboration with neuroscientists working in clinical research centers addressing human communication disorders might foster research in this area. It is hoped that this paper will encourage future research on speech motor control disorders to address the principles of neural plasticity and their application for rehabilitation. PMID:18230849

  17. On the Relationships between Generative Encodings, Regularity, and Learning Abilities when Evolving Plastic Artificial Neural Networks

    PubMed Central

    Tonelli, Paul; Mouret, Jean-Baptiste

    2013-01-01

    A major goal of bio-inspired artificial intelligence is to design artificial neural networks with abilities that resemble those of animal nervous systems. It is commonly believed that two keys for evolving nature-like artificial neural networks are (1) the developmental process that links genes to nervous systems, which enables the evolution of large, regular neural networks, and (2) synaptic plasticity, which allows neural networks to change during their lifetime. So far, these two topics have been mainly studied separately. The present paper shows that they are actually deeply connected. Using a simple operant conditioning task and a classic evolutionary algorithm, we compare three ways to encode plastic neural networks: a direct encoding, a developmental encoding inspired by computational neuroscience models, and a developmental encoding inspired by morphogen gradients (similar to HyperNEAT). Our results suggest that using a developmental encoding could improve the learning abilities of evolved, plastic neural networks. Complementary experiments reveal that this result is likely the consequence of the bias of developmental encodings towards regular structures: (1) in our experimental setup, encodings that tend to produce more regular networks yield networks with better general learning abilities; (2) whatever the encoding is, networks that are the more regular are statistically those that have the best learning abilities. PMID:24236099

  18. Plasticity and neural stem cells in the enteric nervous system.

    PubMed

    Schäfer, Karl-Herbert; Van Ginneken, Chris; Copray, Sjef

    2009-12-01

    The enteric nervous system (ENS) is a highly organized part of the autonomic nervous system, which innervates the whole gastrointestinal tract by several interconnected neuronal networks. The ENS changes during development and keeps throughout its lifespan a significant capacity to adapt to microenvironmental influences, be it in inflammatory bowel diseases or changing dietary habits. The presence of neural stem cells in the pre-, postnatal, and adult gut might be one of the prerequisites to adapt to changing conditions. During the last decade, the ENS has increasingly come into the focus of clinical neural stem cell research, forming a considerable pool of neural crest derived stem cells, which could be used for cell therapy of dysganglionosis, that is, diseases based on the deficient or insufficient colonization of the gut by neural crest derived stem cells; in addition, the ENS could be an easily accessible neural stem cell source for cell replacement therapies for neurodegenerative disorders or traumatic lesions of the central nervous system. PMID:19943347

  19. Plasticity in memristive devices for spiking neural networks.

    PubMed

    Saïghi, Sylvain; Mayr, Christian G; Serrano-Gotarredona, Teresa; Schmidt, Heidemarie; Lecerf, Gwendal; Tomas, Jean; Grollier, Julie; Boyn, Sören; Vincent, Adrien F; Querlioz, Damien; La Barbera, Selina; Alibart, Fabien; Vuillaume, Dominique; Bichler, Olivier; Gamrat, Christian; Linares-Barranco, Bernabé

    2015-01-01

    Memristive devices present a new device technology allowing for the realization of compact non-volatile memories. Some of them are already in the process of industrialization. Additionally, they exhibit complex multilevel and plastic behaviors, which make them good candidates for the implementation of artificial synapses in neuromorphic engineering. However, memristive effects rely on diverse physical mechanisms, and their plastic behaviors differ strongly from one technology to another. Here, we present measurements performed on different memristive devices and the opportunities that they provide. We show that they can be used to implement different learning rules whose properties emerge directly from device physics: real time or accelerated operation, deterministic or stochastic behavior, long term or short term plasticity. We then discuss how such devices might be integrated into a complete architecture. These results highlight that there is no unique way to exploit memristive devices in neuromorphic systems. Understanding and embracing device physics is the key for their optimal use. PMID:25784849

  20. Plasticity in memristive devices for spiking neural networks

    PubMed Central

    Saïghi, Sylvain; Mayr, Christian G.; Serrano-Gotarredona, Teresa; Schmidt, Heidemarie; Lecerf, Gwendal; Tomas, Jean; Grollier, Julie; Boyn, Sören; Vincent, Adrien F.; Querlioz, Damien; La Barbera, Selina; Alibart, Fabien; Vuillaume, Dominique; Bichler, Olivier; Gamrat, Christian; Linares-Barranco, Bernabé

    2015-01-01

    Memristive devices present a new device technology allowing for the realization of compact non-volatile memories. Some of them are already in the process of industrialization. Additionally, they exhibit complex multilevel and plastic behaviors, which make them good candidates for the implementation of artificial synapses in neuromorphic engineering. However, memristive effects rely on diverse physical mechanisms, and their plastic behaviors differ strongly from one technology to another. Here, we present measurements performed on different memristive devices and the opportunities that they provide. We show that they can be used to implement different learning rules whose properties emerge directly from device physics: real time or accelerated operation, deterministic or stochastic behavior, long term or short term plasticity. We then discuss how such devices might be integrated into a complete architecture. These results highlight that there is no unique way to exploit memristive devices in neuromorphic systems. Understanding and embracing device physics is the key for their optimal use. PMID:25784849

  1. Stage-dependent plasticity of the anterior neural folds to form neural crest.

    PubMed

    Ezin, Maxellende; Barembaum, Meyer; Bronner, Marianne E

    2014-01-01

    The anterior neural fold (ANF) is the only region of the neural tube that does not produce neural crest cells. Instead, ANF cells contribute to the olfactory and lens placodes, as well as to the forebrain and epidermis. Here, we test the ability of the ANF to form neural crest by performing heterotopic transplantation experiments in the chick embryo. We find that, at the neurula stage (HH stage 7), the chick ANF retains the ability to form migrating neural crest cells when transplanted caudally to rostral hindbrain levels. This ability is gradually lost, such that by HH9, this tissue appears to no longer have the potential to form neural crest. In contrast to the ANF, hindbrain dorsal neural folds transplanted rostrally fail to contribute to the olfactory placode but instead continue to generate neural crest cells. The transcription factor GANF is expressed in the ANF and its morpholino-mediated knock-down expands the neural crest domain rostrally and results in the production of migratory cells emerging from the ANF; however, these cells fail to express the HNK1 neural crest marker, suggesting only partial conversion. Our results show that environmental factors can imbue the chick anterior neural folds to assume a neural crest cell fate via a mechanism that partially involves loss of GANF. PMID:25264214

  2. Principles of Experience-Dependent Neural Plasticity: Implications for Rehabilitation after Brain Damage

    ERIC Educational Resources Information Center

    Kleim, Jeffrey A.; Jones, Theresa A.

    2008-01-01

    Purpose: This paper reviews 10 principles of experience-dependent neural plasticity and considerations in applying them to the damaged brain. Method: Neuroscience research using a variety of models of learning, neurological disease, and trauma are reviewed from the perspective of basic neuroscientists but in a manner intended to be useful for the…

  3. Swallowing and Dysphagia Rehabilitation: Translating Principles of Neural Plasticity into Clinically Oriented Evidence

    ERIC Educational Resources Information Center

    Robbins, JoAnne; Butler, Susan G.; Daniels, Stephanie K.; Gross, Roxann Diez; Langmore, Susan; Lazarus, Cathy L.; Martin-Harris, Bonnie; McCabe, Daniel; Musson, Nan; Rosenbek, John

    2008-01-01

    Purpose: This review presents the state of swallowing rehabilitation science as it relates to evidence for neural plastic changes in the brain. The case is made for essential collaboration between clinical and basic scientists to expand the positive influences of dysphagia rehabilitation in synergy with growth in technology and knowledge. The…

  4. Neural Plasticity in Multiple Sclerosis: The Functional and Molecular Background

    PubMed Central

    Ksiazek-Winiarek, Dominika Justyna; Szpakowski, Piotr; Glabinski, Andrzej

    2015-01-01

    Multiple sclerosis is an autoimmune neurodegenerative disorder resulting in motor dysfunction and cognitive decline. The inflammatory and neurodegenerative changes seen in the brains of MS patients lead to progressive disability and increasing brain atrophy. The most common type of MS is characterized by episodes of clinical exacerbations and remissions. This suggests the presence of compensating mechanisms for accumulating damage. Apart from the widely known repair mechanisms like remyelination, another important phenomenon is neuronal plasticity. Initially, neuroplasticity was connected with the developmental stages of life; however, there is now growing evidence confirming that structural and functional reorganization occurs throughout our lifetime. Several functional studies, utilizing such techniques as fMRI, TBS, or MRS, have provided valuable data about the presence of neuronal plasticity in MS patients. CNS ability to compensate for neuronal damage is most evident in RR-MS; however it has been shown that brain plasticity is also preserved in patients with substantial brain damage. Regardless of the numerous studies, the molecular background of neuronal plasticity in MS is still not well understood. Several factors, like IL-1β, BDNF, PDGF, or CB1Rs, have been implicated in functional recovery from the acute phase of MS and are thus considered as potential therapeutic targets. PMID:26229689

  5. Neural circuit remodeling and structural plasticity in the cortex during chronic pain

    PubMed Central

    Kim, Woojin

    2016-01-01

    Damage in the periphery or spinal cord induces maladaptive plastic changes along the somatosensory nervous system from the periphery to the cortex, often leading to chronic pain. Although the role of neural circuit remodeling and structural synaptic plasticity in the 'pain matrix' cortices in chronic pain has been thought as a secondary epiphenomenon to altered nociceptive signaling in the spinal cord, progress in whole brain imaging studies on human patients and animal models has suggested a possibility that plastic changes in cortical neural circuits may actively contribute to chronic pain symptoms. Furthermore, recent development in two-photon microscopy and fluorescence labeling techniques have enabled us to longitudinally trace the structural and functional changes in local circuits, single neurons and even individual synapses in the brain of living animals. These technical advances has started to reveal that cortical structural remodeling following tissue or nerve damage could rapidly occur within days, which are temporally correlated with functional plasticity of cortical circuits as well as the development and maintenance of chronic pain behavior, thereby modifying the previous concept that it takes much longer periods (e.g. months or years). In this review, we discuss the relation of neural circuit plasticity in the 'pain matrix' cortices, such as the anterior cingulate cortex, prefrontal cortex and primary somatosensory cortex, with chronic pain. We also introduce how to apply long-term in vivo two-photon imaging approaches for the study of pathophysiological mechanisms of chronic pain. PMID:26807017

  6. Enhancement of Spike-Timing-Dependent Plasticity in Spiking Neural Systems with Noise.

    PubMed

    Nobukawa, Sou; Nishimura, Haruhiko

    2016-08-01

    Synaptic plasticity is widely recognized to support adaptable information processing in the brain. Spike-timing-dependent plasticity, one subtype of plasticity, can lead to synchronous spike propagation with temporal spiking coding information. Recently, it was reported that in a noisy environment, like the actual brain, the spike-timing-dependent plasticity may be made efficient by the effect of stochastic resonance. In the stochastic resonance, the presence of noise helps a nonlinear system in amplifying a weak (under barrier) signal. However, previous studies have ignored the full variety of spiking patterns and many relevant factors in neural dynamics. Thus, in order to prove the physiological possibility for the enhancement of spike-timing-dependent plasticity by stochastic resonance, it is necessary to demonstrate that this stochastic resonance arises in realistic cortical neural systems. In this study, we evaluate this stochastic resonance phenomenon in the realistic cortical neural system described by the Izhikevich neuron model and compare the characteristics of typical spiking patterns of regular spiking, intrinsically bursting and chattering experimentally observed in the cortex. PMID:26678248

  7. Intrinsic Plasticity for Natural Competition in Koniocortex-Like Neural Networks.

    PubMed

    Peláez, Francisco Javier Ropero; Aguiar-Furucho, Mariana Antonia; Andina, Diego

    2016-08-01

    In this paper, we use the neural property known as intrinsic plasticity to develop neural network models that resemble the koniocortex, the fourth layer of sensory cortices. These models evolved from a very basic two-layered neural network to a complex associative koniocortex network. In the initial network, intrinsic and synaptic plasticity govern the shifting of the activation function, and the modification of synaptic weights, respectively. In this first version, competition is forced, so that the most activated neuron is arbitrarily set to one and the others to zero, while in the second, competition occurs naturally due to inhibition between second layer neurons. In the third version of the network, whose architecture is similar to the koniocortex, competition also occurs naturally owing to the interplay between inhibitory interneurons and synaptic and intrinsic plasticity. A more complex associative neural network was developed based on this basic koniocortex-like neural network, capable of dealing with incomplete patterns and ideally suited to operating similarly to a learning vector quantization network. We also discuss the biological plausibility of the networks and their role in a more complex thalamocortical model. PMID:27255800

  8. Brain-Controlled Neuromuscular Stimulation to Drive Neural Plasticity and Functional Recovery

    PubMed Central

    Ethier, C.; Gallego, J.A.; Miller, L.E.

    2015-01-01

    There is mounting evidence that appropriately timed neuromuscular stimulation can induce neural plasticity and generate functional recovery from motor disorders. This review addresses the idea that coordinating stimulation with a patient’s voluntary effort might further enhance neurorehabilitation. Studies in cell cultures and behaving animals have delineated the rules underlying neural plasticity when single neurons are used as triggers. However, the rules governing more complex stimuli and larger networks are less well understood. We argue that functional recovery might be optimized if stimulation were modulated by a brain machine interface, to matched the details of the patient’s voluntary intent. The potential of this novel approach highlights the need for a better understanding of the complex rules underlying this form of plasticity. PMID:25827275

  9. Brain-controlled neuromuscular stimulation to drive neural plasticity and functional recovery.

    PubMed

    Ethier, C; Gallego, J A; Miller, L E

    2015-08-01

    There is mounting evidence that appropriately timed neuromuscular stimulation can induce neural plasticity and generate functional recovery from motor disorders. This review addresses the idea that coordinating stimulation with a patient's voluntary effort might further enhance neurorehabilitation. Studies in cell cultures and behaving animals have delineated the rules underlying neural plasticity when single neurons are used as triggers. However, the rules governing more complex stimuli and larger networks are less well understood. We argue that functional recovery might be optimized if stimulation were modulated by a brain machine interface, to match the details of the patient's voluntary intent. The potential of this novel approach highlights the need for a better understanding of the complex rules underlying this form of plasticity. PMID:25827275

  10. Large-Scale Simulations of Plastic Neural Networks on Neuromorphic Hardware

    PubMed Central

    Knight, James C.; Tully, Philip J.; Kaplan, Bernhard A.; Lansner, Anders; Furber, Steve B.

    2016-01-01

    SpiNNaker is a digital, neuromorphic architecture designed for simulating large-scale spiking neural networks at speeds close to biological real-time. Rather than using bespoke analog or digital hardware, the basic computational unit of a SpiNNaker system is a general-purpose ARM processor, allowing it to be programmed to simulate a wide variety of neuron and synapse models. This flexibility is particularly valuable in the study of biological plasticity phenomena. A recently proposed learning rule based on the Bayesian Confidence Propagation Neural Network (BCPNN) paradigm offers a generic framework for modeling the interaction of different plasticity mechanisms using spiking neurons. However, it can be computationally expensive to simulate large networks with BCPNN learning since it requires multiple state variables for each synapse, each of which needs to be updated every simulation time-step. We discuss the trade-offs in efficiency and accuracy involved in developing an event-based BCPNN implementation for SpiNNaker based on an analytical solution to the BCPNN equations, and detail the steps taken to fit this within the limited computational and memory resources of the SpiNNaker architecture. We demonstrate this learning rule by learning temporal sequences of neural activity within a recurrent attractor network which we simulate at scales of up to 2.0 × 104 neurons and 5.1 × 107 plastic synapses: the largest plastic neural network ever to be simulated on neuromorphic hardware. We also run a comparable simulation on a Cray XC-30 supercomputer system and find that, if it is to match the run-time of our SpiNNaker simulation, the super computer system uses approximately 45× more power. This suggests that cheaper, more power efficient neuromorphic systems are becoming useful discovery tools in the study of plasticity in large-scale brain models. PMID:27092061

  11. Large-Scale Simulations of Plastic Neural Networks on Neuromorphic Hardware.

    PubMed

    Knight, James C; Tully, Philip J; Kaplan, Bernhard A; Lansner, Anders; Furber, Steve B

    2016-01-01

    SpiNNaker is a digital, neuromorphic architecture designed for simulating large-scale spiking neural networks at speeds close to biological real-time. Rather than using bespoke analog or digital hardware, the basic computational unit of a SpiNNaker system is a general-purpose ARM processor, allowing it to be programmed to simulate a wide variety of neuron and synapse models. This flexibility is particularly valuable in the study of biological plasticity phenomena. A recently proposed learning rule based on the Bayesian Confidence Propagation Neural Network (BCPNN) paradigm offers a generic framework for modeling the interaction of different plasticity mechanisms using spiking neurons. However, it can be computationally expensive to simulate large networks with BCPNN learning since it requires multiple state variables for each synapse, each of which needs to be updated every simulation time-step. We discuss the trade-offs in efficiency and accuracy involved in developing an event-based BCPNN implementation for SpiNNaker based on an analytical solution to the BCPNN equations, and detail the steps taken to fit this within the limited computational and memory resources of the SpiNNaker architecture. We demonstrate this learning rule by learning temporal sequences of neural activity within a recurrent attractor network which we simulate at scales of up to 2.0 × 104 neurons and 5.1 × 107 plastic synapses: the largest plastic neural network ever to be simulated on neuromorphic hardware. We also run a comparable simulation on a Cray XC-30 supercomputer system and find that, if it is to match the run-time of our SpiNNaker simulation, the super computer system uses approximately 45× more power. This suggests that cheaper, more power efficient neuromorphic systems are becoming useful discovery tools in the study of plasticity in large-scale brain models. PMID:27092061

  12. Neural Plasticity Underlying Visual Perceptual Learning in Aging

    PubMed Central

    Mishra, Jyoti; Rolle, Camarin; Gazzaley, Adam

    2014-01-01

    Healthy aging is associated with a decline in basic perceptual abilities, as well as higher-level cognitive functions such as working memory. In a recent perceptual training study using moving sweeps of Gabor stimuli, Berry et al. (2010) observed that older adults significantly improved discrimination abilities on the most challenging perceptual tasks that presented paired sweeps at rapid rates of 5 & 10 Hz. Berry et al. further showed that this perceptual training engendered transfer-of-benefit to an untrained working memory task. Here, we investigated the neural underpinnings of the improvements in these perceptual tasks, as assessed by event-related potential (ERP) recordings. Early visual ERP components time-locked to stimulus onset were compared pre- and post- training, as well as relative to a no-contact control group. The visual N1 and N2 components were significantly enhanced after training, and the N1 change correlated with improvements in perceptual discrimination on the task. Further, the change observed for the N1 and N2 was associated with the rapidity of the perceptual challenge; the visual N1 (120–150 ms) was enhanced post-training for 10 Hz sweep pairs, while the N2 (240–280 ms) was enhanced for the 5 Hz sweep pairs. We speculate that these observed post-training neural enhancements reflect improvements by older adults in the allocation of attention that is required to accurately dissociate perceptually overlapping stimuli when presented in rapid sequence. PMID:25218557

  13. Neural plasticity underlying visual perceptual learning in aging.

    PubMed

    Mishra, Jyoti; Rolle, Camarin; Gazzaley, Adam

    2015-07-01

    Healthy aging is associated with a decline in basic perceptual abilities, as well as higher-level cognitive functions such as working memory. In a recent perceptual training study using moving sweeps of Gabor stimuli, Berry et al. (2010) observed that older adults significantly improved discrimination abilities on the most challenging perceptual tasks that presented paired sweeps at rapid rates of 5 and 10 Hz. Berry et al. further showed that this perceptual training engendered transfer-of-benefit to an untrained working memory task. Here, we investigated the neural underpinnings of the improvements in these perceptual tasks, as assessed by event-related potential (ERP) recordings. Early visual ERP components time-locked to stimulus onset were compared pre- and post-training, as well as relative to a no-contact control group. The visual N1 and N2 components were significantly enhanced after training, and the N1 change correlated with improvements in perceptual discrimination on the task. Further, the change observed for the N1 and N2 was associated with the rapidity of the perceptual challenge; the visual N1 (120-150 ms) was enhanced post-training for 10 Hz sweep pairs, while the N2 (240-280 ms) was enhanced for the 5 Hz sweep pairs. We speculate that these observed post-training neural enhancements reflect improvements by older adults in the allocation of attention that is required to accurately dissociate perceptually overlapping stimuli when presented in rapid sequence. This article is part of a Special Issue entitled SI: Memory Å. PMID:25218557

  14. The common neural parasite Pseudoloma neurophilia is associated with altered startle response habituation in adult zebrafish (Danio rerio): Implications for the zebrafish as a model organism.

    PubMed

    Spagnoli, Sean; Xue, Lan; Kent, Michael L

    2015-09-15

    The zebrafish's potential as a model for human neurobehavioral research appears nearly limitless despite its relatively recent emergence as an experimental organism. Since the zebrafish has only been part of the research community for a handful of decades, pathogens from its commercial origins continue to plague laboratory stocks. One such pathogen is Pseudoloma neurophilia, a common microparasite in zebrafish laboratories world-wide that generally produces subclinical infections. Given its high prevalence, its predilection for the host's brain and spinal cord, and the delicate nature of neurobehavioral research, the behavioral consequences of subclinical P. neurophilia infection must be explored. Fish infected via cohabitation were tested for startle response habituation in parallel with controls in a device that administered ten taps over 10 min along with taps at 18 and 60 min to evaluate habituation extinction. After testing, fish were euthanized and evaluated for infection via histopathology. Infected fish had a significantly smaller reduction in startle velocity during habituation compared to uninfected tankmates and controls. Habituation was eliminated in infected and control fish at 18 min, whereas exposed negative fish retained partial habituation at 18 min. Infection was also associated with enhanced capture evasion: Despite the absence of external symptoms, infected fish tended to be caught later than uninfected fish netted from the same tank. The combination of decreased overall habituation, early extinction of habituation compared to uninfected cohorts, and enhanced netting evasion indicates that P. neurophilia infection is associated with a behavioral phenotype distinct from that of controls and uninfected cohorts. Because of its prevalence in zebrafish facilities, P. neurophilia has the potential to insidiously influence a wide range of neurobehavioral studies if these associations are causative. Rigorous health screening is therefore vital to the

  15. The neural plasticity of other-race face recognition.

    PubMed

    Tanaka, James W; Pierce, Lara J

    2009-03-01

    Although it is well established that people are better at recognizing own-race faces than at recognizing other-race faces, the neural mechanisms mediating this advantage are not well understood. In this study, Caucasian participants were trained to differentiate African American (or Hispanic) faces at the individual level (e.g., Joe, Bob) and to categorize Hispanic (or African American) faces at the basic level of race (e.g., Hispanic, African American). Behaviorally, subordinate-level individuation training led to improved performance on a posttraining recognition test, relative to basic-level training. As measured by event-related potentials, subordinate- and basic-level training had relatively little effect on the face N170 component. However, as compared with basic-level training, subordinate-level training elicited an increased response in the posterior expert N250 component. These results demonstrate that learning to discriminate other-race faces at the subordinate level of the individual leads to improved recognition and enhanced activation of the expert N250 component. PMID:19246333

  16. Training-induced neural plasticity in golf novices.

    PubMed

    Bezzola, Ladina; Mérillat, Susan; Gaser, Christian; Jäncke, Lutz

    2011-08-31

    Previous neuroimaging studies in the field of motor learning have shown that learning a new skill induces specific changes of neural gray and white matter in human brain areas necessary to control the practiced task. Former longitudinal studies investigating motor skill learning have used strict training protocols with little ecological validity rather than physical leisure activities, although there are several retrospective and cross-sectional studies suggesting neuroprotective effects of physical leisure activities. In the present longitudinal MRI study, we used voxel-based morphometry to investigate training-induced gray matter changes in golf novices between the age of 40 and 60 years, an age period when an active life style is assumed to counteract cognitive decline. As a main result, we demonstrate that 40 h of golf practice, performed as a leisure activity with highly individual training protocols, are associated with gray matter increases in a task-relevant cortical network encompassing sensorimotor regions and areas belonging to the dorsal stream. A new and striking result is the relationship between training intensity (time needed to complete the 40 training hours) and structural changes observed in the parieto-occipital junction. Thus, we demonstrate that a physical leisure activity induces training-dependent changes in gray matter and assume that a strict and controlled training protocol is not mandatory for training-induced adaptations of gray matter. PMID:21880905

  17. Plasticity in the neural coding of auditory space in the mammalian brain

    NASA Astrophysics Data System (ADS)

    King, Andrew J.; Parsons, Carl H.; Moore, David R.

    2000-10-01

    Sound localization relies on the neural processing of monaural and binaural spatial cues that arise from the way sounds interact with the head and external ears. Neurophysiological studies of animals raised with abnormal sensory inputs show that the map of auditory space in the superior colliculus is shaped during development by both auditory and visual experience. An example of this plasticity is provided by monaural occlusion during infancy, which leads to compensatory changes in auditory spatial tuning that tend to preserve the alignment between the neural representations of visual and auditory space. Adaptive changes also take place in sound localization behavior, as demonstrated by the fact that ferrets raised and tested with one ear plugged learn to localize as accurately as control animals. In both cases, these adjustments may involve greater use of monaural spectral cues provided by the other ear. Although plasticity in the auditory space map seems to be restricted to development, adult ferrets show some recovery of sound localization behavior after long-term monaural occlusion. The capacity for behavioral adaptation is, however, task dependent, because auditory spatial acuity and binaural unmasking (a measure of the spatial contribution to the "cocktail party effect") are permanently impaired by chronically plugging one ear, both in infancy but especially in adulthood. Experience-induced plasticity allows the neural circuitry underlying sound localization to be customized to individual characteristics, such as the size and shape of the head and ears, and to compensate for natural conductive hearing losses, including those associated with middle ear disease in infancy.

  18. High quality garbage: A neural network plastic sorter in hardware and software

    SciTech Connect

    Stanton, S.L.; Alam, M.K.; Hebner, G.A.

    1993-09-01

    In order to produce pure polymer streams from post-consumer waste plastics, a quick, accurate and relatively inexpensive method of sorting needs to be implemented. This technology has been demonstrated by using near-infrared spectroscopy reflectance data and neural network classification techniques. Backpropagation neural network routines have been developed to run real-time sortings in the lab, using a laboratory-grade spectrometer. In addition, a new reflectance spectrometer has been developed which is fast enough for commercial use. Initial training and test sets taken with the laboratory instrument show that a network is capable of learning 100% when classifying 5 groups of plastic (HDPE and LDPE combined), and up to 100% when classifying 6 groups. Initial data sets from the new instrument have classified plastics into all seven groups with varying degrees of success. One of the initial networks has been implemented in hardware, for high speed computations, and thus rapid classification. Two neural accelerator systems have been evaluated, one based on the Intel 8017ONX chip, and another on the AT&T ANNA chip.

  19. Global and local missions of cAMP signaling in neural plasticity, learning, and memory

    PubMed Central

    Lee, Daewoo

    2015-01-01

    The fruit fly Drosophila melanogaster has been a popular model to study cAMP signaling and resultant behaviors due to its powerful genetic approaches. All molecular components (AC, PDE, PKA, CREB, etc) essential for cAMP signaling have been identified in the fly. Among them, adenylyl cyclase (AC) gene rutabaga and phosphodiesterase (PDE) gene dunce have been intensively studied to understand the role of cAMP signaling. Interestingly, these two mutant genes were originally identified on the basis of associative learning deficits. This commentary summarizes findings on the role of cAMP in Drosophila neuronal excitability, synaptic plasticity and memory. It mainly focuses on two distinct mechanisms (global versus local) regulating excitatory and inhibitory synaptic plasticity related to cAMP homeostasis. This dual regulatory role of cAMP is to increase the strength of excitatory neural circuits on one hand, but to act locally on postsynaptic GABA receptors to decrease inhibitory synaptic plasticity on the other. Thus the action of cAMP could result in a global increase in the neural circuit excitability and memory. Implications of this cAMP signaling related to drug discovery for neural diseases are also described. PMID:26300775

  20. Sleep Drive Is Encoded by Neural Plastic Changes in a Dedicated Circuit.

    PubMed

    Liu, Sha; Liu, Qili; Tabuchi, Masashi; Wu, Mark N

    2016-06-01

    Prolonged wakefulness leads to an increased pressure for sleep, but how this homeostatic drive is generated and subsequently persists is unclear. Here, from a neural circuit screen in Drosophila, we identify a subset of ellipsoid body (EB) neurons whose activation generates sleep drive. Patch-clamp analysis indicates these EB neurons are highly sensitive to sleep loss, switching from spiking to burst-firing modes. Functional imaging and translational profiling experiments reveal that elevated sleep need triggers reversible increases in cytosolic Ca(2+) levels, NMDA receptor expression, and structural markers of synaptic strength, suggesting these EB neurons undergo "sleep-need"-dependent plasticity. Strikingly, the synaptic plasticity of these EB neurons is both necessary and sufficient for generating sleep drive, indicating that sleep pressure is encoded by plastic changes within this circuit. These studies define an integrator circuit for sleep homeostasis and provide a mechanism explaining the generation and persistence of sleep drive. PMID:27212237

  1. Calcium dependent plasticity applied to repetitive transcranial magnetic stimulation with a neural field model.

    PubMed

    Wilson, M T; Fung, P K; Robinson, P A; Shemmell, J; Reynolds, J N J

    2016-08-01

    The calcium dependent plasticity (CaDP) approach to the modeling of synaptic weight change is applied using a neural field approach to realistic repetitive transcranial magnetic stimulation (rTMS) protocols. A spatially-symmetric nonlinear neural field model consisting of populations of excitatory and inhibitory neurons is used. The plasticity between excitatory cell populations is then evaluated using a CaDP approach that incorporates metaplasticity. The direction and size of the plasticity (potentiation or depression) depends on both the amplitude of stimulation and duration of the protocol. The breaks in the inhibitory theta-burst stimulation protocol are crucial to ensuring that the stimulation bursts are potentiating in nature. Tuning the parameters of a spike-timing dependent plasticity (STDP) window with a Monte Carlo approach to maximize agreement between STDP predictions and the CaDP results reproduces a realistically-shaped window with two regions of depression in agreement with the existing literature. Developing understanding of how TMS interacts with cells at a network level may be important for future investigation. PMID:27259518

  2. Perspectives of TRPV1 Function on the Neurogenesis and Neural Plasticity

    PubMed Central

    Ramírez-Barrantes, R.; Cordova, C.; Poblete, H.; Muñoz, P.; Marchant, I.; Wianny, F.; Olivero, P.

    2016-01-01

    The development of new strategies to renew and repair neuronal networks using neural plasticity induced by stem cell graft could enable new therapies to cure diseases that were considered lethal until now. In adequate microenvironment a neuronal progenitor must receive molecular signal of a specific cellular context to determine fate, differentiation, and location. TRPV1, a nonselective calcium channel, is expressed in neurogenic regions of the brain like the subgranular zone of the hippocampal dentate gyrus and the telencephalic subventricular zone, being valuable for neural differentiation and neural plasticity. Current data show that TRPV1 is involved in several neuronal functions as cytoskeleton dynamics, cell migration, survival, and regeneration of injured neurons, incorporating several stimuli in neurogenesis and network integration. The function of TRPV1 in the brain is under intensive investigation, due to multiple places where it has been detected and its sensitivity for different chemical and physical agonists, and a new role of TRPV1 in brain function is now emerging as a molecular tool for survival and control of neural stem cells. PMID:26881090

  3. Dynamic neural networking as a basis for plasticity in the control of heart rate.

    PubMed

    Kember, G; Armour, J A; Zamir, M

    2013-01-21

    A model is proposed in which the relationship between individual neurons within a neural network is dynamically changing to the effect of providing a measure of "plasticity" in the control of heart rate. The neural network on which the model is based consists of three populations of neurons residing in the central nervous system, the intrathoracic extracardiac nervous system, and the intrinsic cardiac nervous system. This hierarchy of neural centers is used to challenge the classical view that the control of heart rate, a key clinical index, resides entirely in central neuronal command (spinal cord, medulla oblongata, and higher centers). Our results indicate that dynamic networking allows for the possibility of an interplay among the three populations of neurons to the effect of altering the order of control of heart rate among them. This interplay among the three levels of control allows for different neural pathways for the control of heart rate to emerge under different blood flow demands or disease conditions and, as such, it has significant clinical implications because current understanding and treatment of heart rate anomalies are based largely on a single level of control and on neurons acting in unison as a single entity rather than individually within a (plastically) interconnected network. PMID:23041448

  4. Inactivity-induced respiratory plasticity: protecting the drive to breathe in disorders that reduce respiratory neural activity.

    PubMed

    Strey, K A; Baertsch, N A; Baker-Herman, T L

    2013-11-01

    Multiple forms of plasticity are activated following reduced respiratory neural activity. For example, in ventilated rats, a central neural apnea elicits a rebound increase in phrenic and hypoglossal burst amplitude upon resumption of respiratory neural activity, forms of plasticity called inactivity-induced phrenic and hypoglossal motor facilitation (iPMF and iHMF), respectively. Here, we provide a conceptual framework for plasticity following reduced respiratory neural activity to guide future investigations. We review mechanisms giving rise to iPMF and iHMF, present new data suggesting that inactivity-induced plasticity is observed in inspiratory intercostals (iIMF) and point out gaps in our knowledge. We then survey conditions relevant to human health characterized by reduced respiratory neural activity and discuss evidence that inactivity-induced plasticity is elicited during these conditions. Understanding the physiological impact and circumstances in which inactivity-induced respiratory plasticity is elicited may yield novel insights into the treatment of disorders characterized by reductions in respiratory neural activity. PMID:23816599

  5. Inactivity-induced respiratory plasticity: Protecting the drive to breathe in disorders that reduce respiratory neural activity☆

    PubMed Central

    Strey, K.A.; Baertsch, N.A.; Baker-Herman, T.L.

    2013-01-01

    Multiple forms of plasticity are activated following reduced respiratory neural activity. For example, in ventilated rats, a central neural apnea elicits a rebound increase in phrenic and hypoglossal burst amplitude upon resumption of respiratory neural activity, forms of plasticity called inactivity-induced phrenic and hypoglossal motor facilitation (iPMF and iHMF), respectively. Here, we provide a conceptual framework for plasticity following reduced respiratory neural activity to guide future investigations. We review mechanisms giving rise to iPMF and iHMF, present new data suggesting that inactivity-induced plasticity is observed in inspiratory intercostals (iIMF) and point out gaps in our knowledge. We then survey conditions relevant to human health characterized by reduced respiratory neural activity and discuss evidence that inactivity-induced plasticity is elicited during these conditions. Understanding the physiological impact and circumstances in which inactivity-induced respiratory plasticity is elicited may yield novel insights into the treatment of disorders characterized by reductions in respiratory neural activity. PMID:23816599

  6. A neuromorphic implementation of multiple spike-timing synaptic plasticity rules for large-scale neural networks

    PubMed Central

    Wang, Runchun M.; Hamilton, Tara J.; Tapson, Jonathan C.; van Schaik, André

    2015-01-01

    We present a neuromorphic implementation of multiple synaptic plasticity learning rules, which include both Spike Timing Dependent Plasticity (STDP) and Spike Timing Dependent Delay Plasticity (STDDP). We present a fully digital implementation as well as a mixed-signal implementation, both of which use a novel dynamic-assignment time-multiplexing approach and support up to 226 (64M) synaptic plasticity elements. Rather than implementing dedicated synapses for particular types of synaptic plasticity, we implemented a more generic synaptic plasticity adaptor array that is separate from the neurons in the neural network. Each adaptor performs synaptic plasticity according to the arrival times of the pre- and post-synaptic spikes assigned to it, and sends out a weighted or delayed pre-synaptic spike to the post-synaptic neuron in the neural network. This strategy provides great flexibility for building complex large-scale neural networks, as a neural network can be configured for multiple synaptic plasticity rules without changing its structure. We validate the proposed neuromorphic implementations with measurement results and illustrate that the circuits are capable of performing both STDP and STDDP. We argue that it is practical to scale the work presented here up to 236 (64G) synaptic adaptors on a current high-end FPGA platform. PMID:26041985

  7. Synaptic plasticity in a recurrent neural network for versatile and adaptive behaviors of a walking robot.

    PubMed

    Grinke, Eduard; Tetzlaff, Christian; Wörgötter, Florentin; Manoonpong, Poramate

    2015-01-01

    Walking animals, like insects, with little neural computing can effectively perform complex behaviors. For example, they can walk around their environment, escape from corners/deadlocks, and avoid or climb over obstacles. While performing all these behaviors, they can also adapt their movements to deal with an unknown situation. As a consequence, they successfully navigate through their complex environment. The versatile and adaptive abilities are the result of an integration of several ingredients embedded in their sensorimotor loop. Biological studies reveal that the ingredients include neural dynamics, plasticity, sensory feedback, and biomechanics. Generating such versatile and adaptive behaviors for a many degrees-of-freedom (DOFs) walking robot is a challenging task. Thus, in this study, we present a bio-inspired approach to solve this task. Specifically, the approach combines neural mechanisms with plasticity, exteroceptive sensory feedback, and biomechanics. The neural mechanisms consist of adaptive neural sensory processing and modular neural locomotion control. The sensory processing is based on a small recurrent neural network consisting of two fully connected neurons. Online correlation-based learning with synaptic scaling is applied to adequately change the connections of the network. By doing so, we can effectively exploit neural dynamics (i.e., hysteresis effects and single attractors) in the network to generate different turning angles with short-term memory for a walking robot. The turning information is transmitted as descending steering signals to the neural locomotion control which translates the signals into motor actions. As a result, the robot can walk around and adapt its turning angle for avoiding obstacles in different situations. The adaptation also enables the robot to effectively escape from sharp corners or deadlocks. Using backbone joint control embedded in the the locomotion control allows the robot to climb over small obstacles

  8. Synaptic plasticity in a recurrent neural network for versatile and adaptive behaviors of a walking robot

    PubMed Central

    Grinke, Eduard; Tetzlaff, Christian; Wörgötter, Florentin; Manoonpong, Poramate

    2015-01-01

    Walking animals, like insects, with little neural computing can effectively perform complex behaviors. For example, they can walk around their environment, escape from corners/deadlocks, and avoid or climb over obstacles. While performing all these behaviors, they can also adapt their movements to deal with an unknown situation. As a consequence, they successfully navigate through their complex environment. The versatile and adaptive abilities are the result of an integration of several ingredients embedded in their sensorimotor loop. Biological studies reveal that the ingredients include neural dynamics, plasticity, sensory feedback, and biomechanics. Generating such versatile and adaptive behaviors for a many degrees-of-freedom (DOFs) walking robot is a challenging task. Thus, in this study, we present a bio-inspired approach to solve this task. Specifically, the approach combines neural mechanisms with plasticity, exteroceptive sensory feedback, and biomechanics. The neural mechanisms consist of adaptive neural sensory processing and modular neural locomotion control. The sensory processing is based on a small recurrent neural network consisting of two fully connected neurons. Online correlation-based learning with synaptic scaling is applied to adequately change the connections of the network. By doing so, we can effectively exploit neural dynamics (i.e., hysteresis effects and single attractors) in the network to generate different turning angles with short-term memory for a walking robot. The turning information is transmitted as descending steering signals to the neural locomotion control which translates the signals into motor actions. As a result, the robot can walk around and adapt its turning angle for avoiding obstacles in different situations. The adaptation also enables the robot to effectively escape from sharp corners or deadlocks. Using backbone joint control embedded in the the locomotion control allows the robot to climb over small obstacles

  9. Enabling functional neural circuit simulations with distributed computing of neuromodulated plasticity.

    PubMed

    Potjans, Wiebke; Morrison, Abigail; Diesmann, Markus

    2010-01-01

    A major puzzle in the field of computational neuroscience is how to relate system-level learning in higher organisms to synaptic plasticity. Recently, plasticity rules depending not only on pre- and post-synaptic activity but also on a third, non-local neuromodulatory signal have emerged as key candidates to bridge the gap between the macroscopic and the microscopic level of learning. Crucial insights into this topic are expected to be gained from simulations of neural systems, as these allow the simultaneous study of the multiple spatial and temporal scales that are involved in the problem. In particular, synaptic plasticity can be studied during the whole learning process, i.e., on a time scale of minutes to hours and across multiple brain areas. Implementing neuromodulated plasticity in large-scale network simulations where the neuromodulatory signal is dynamically generated by the network itself is challenging, because the network structure is commonly defined purely by the connectivity graph without explicit reference to the embedding of the nodes in physical space. Furthermore, the simulation of networks with realistic connectivity entails the use of distributed computing. A neuromodulated synapse must therefore be informed in an efficient way about the neuromodulatory signal, which is typically generated by a population of neurons located on different machines than either the pre- or post-synaptic neuron. Here, we develop a general framework to solve the problem of implementing neuromodulated plasticity in a time-driven distributed simulation, without reference to a particular implementation language, neuromodulator, or neuromodulated plasticity mechanism. We implement our framework in the simulator NEST and demonstrate excellent scaling up to 1024 processors for simulations of a recurrent network incorporating neuromodulated spike-timing dependent plasticity. PMID:21151370

  10. Enabling Functional Neural Circuit Simulations with Distributed Computing of Neuromodulated Plasticity

    PubMed Central

    Potjans, Wiebke; Morrison, Abigail; Diesmann, Markus

    2010-01-01

    A major puzzle in the field of computational neuroscience is how to relate system-level learning in higher organisms to synaptic plasticity. Recently, plasticity rules depending not only on pre- and post-synaptic activity but also on a third, non-local neuromodulatory signal have emerged as key candidates to bridge the gap between the macroscopic and the microscopic level of learning. Crucial insights into this topic are expected to be gained from simulations of neural systems, as these allow the simultaneous study of the multiple spatial and temporal scales that are involved in the problem. In particular, synaptic plasticity can be studied during the whole learning process, i.e., on a time scale of minutes to hours and across multiple brain areas. Implementing neuromodulated plasticity in large-scale network simulations where the neuromodulatory signal is dynamically generated by the network itself is challenging, because the network structure is commonly defined purely by the connectivity graph without explicit reference to the embedding of the nodes in physical space. Furthermore, the simulation of networks with realistic connectivity entails the use of distributed computing. A neuromodulated synapse must therefore be informed in an efficient way about the neuromodulatory signal, which is typically generated by a population of neurons located on different machines than either the pre- or post-synaptic neuron. Here, we develop a general framework to solve the problem of implementing neuromodulated plasticity in a time-driven distributed simulation, without reference to a particular implementation language, neuromodulator, or neuromodulated plasticity mechanism. We implement our framework in the simulator NEST and demonstrate excellent scaling up to 1024 processors for simulations of a recurrent network incorporating neuromodulated spike-timing dependent plasticity. PMID:21151370

  11. NMDA Receptors Mediate Stimulus-Timing-Dependent Plasticity and Neural Synchrony in the Dorsal Cochlear Nucleus

    PubMed Central

    Stefanescu, Roxana A.; Shore, Susan E.

    2015-01-01

    Auditory information relayed by auditory nerve fibers and somatosensory information relayed by granule cell parallel fibers converge on the fusiform cells (FCs) of the dorsal cochlear nucleus, the first brain station of the auditory pathway. In vitro, parallel fiber synapses on FCs exhibit spike-timing-dependent plasticity with Hebbian learning rules, partially mediated by the NMDA receptor (NMDAr). Well-timed bimodal auditory-somatosensory stimulation, in vivo equivalent of spike-timing-dependent plasticity, can induce stimulus-timing-dependent plasticity (StTDP) of the FCs spontaneous and tone-evoked firing rates. In healthy guinea pigs, the resulting distribution of StTDP learning rules across a FC neural population is dominated by a Hebbian profile while anti-Hebbian, suppressive and enhancing LRs are less frequent. In this study, we investigate in vivo, the NMDAr contribution to FC baseline activity and long term plasticity. We find that blocking the NMDAr decreases the synchronization of FC- spontaneous activity and mediates differential modulation of FC rate-level functions such that low, and high threshold units are more likely to increase, and decrease, respectively, their maximum amplitudes. Three significant alterations in mean learning-rule profiles were identified: transitions from an initial Hebbian profile towards (1) an anti-Hebbian; (2) a suppressive profile; and (3) transitions from an anti-Hebbian to a Hebbian profile. FC units preserving their learning rules showed instead, NMDAr-dependent plasticity to unimodal acoustic stimulation, with persistent depression of tone-evoked responses changing to persistent enhancement following the NMDAr antagonist. These results reveal a crucial role of the NMDAr in mediating FC baseline activity and long-term plasticity which have important implications for signal processing and auditory pathologies related to maladaptive plasticity of dorsal cochlear nucleus circuitry. PMID:26622224

  12. Effects of cellular homeostatic intrinsic plasticity on dynamical and computational properties of biological recurrent neural networks.

    PubMed

    Naudé, Jérémie; Cessac, Bruno; Berry, Hugues; Delord, Bruno

    2013-09-18

    Homeostatic intrinsic plasticity (HIP) is a ubiquitous cellular mechanism regulating neuronal activity, cardinal for the proper functioning of nervous systems. In invertebrates, HIP is critical for orchestrating stereotyped activity patterns. The functional impact of HIP remains more obscure in vertebrate networks, where higher order cognitive processes rely on complex neural dynamics. The hypothesis has emerged that HIP might control the complexity of activity dynamics in recurrent networks, with important computational consequences. However, conflicting results about the causal relationships between cellular HIP, network dynamics, and computational performance have arisen from machine-learning studies. Here, we assess how cellular HIP effects translate into collective dynamics and computational properties in biological recurrent networks. We develop a realistic multiscale model including a generic HIP rule regulating the neuronal threshold with actual molecular signaling pathways kinetics, Dale's principle, sparse connectivity, synaptic balance, and Hebbian synaptic plasticity (SP). Dynamic mean-field analysis and simulations unravel that HIP sets a working point at which inputs are transduced by large derivative ranges of the transfer function. This cellular mechanism ensures increased network dynamics complexity, robust balance with SP at the edge of chaos, and improved input separability. Although critically dependent upon balanced excitatory and inhibitory drives, these effects display striking robustness to changes in network architecture, learning rates, and input features. Thus, the mechanism we unveil might represent a ubiquitous cellular basis for complex dynamics in neural networks. Understanding this robustness is an important challenge to unraveling principles underlying self-organization around criticality in biological recurrent neural networks. PMID:24048833

  13. Synaptic plasticity, neural circuits, and the emerging role of altered short-term information processing in schizophrenia

    PubMed Central

    Crabtree, Gregg W.; Gogos, Joseph A.

    2014-01-01

    Synaptic plasticity alters the strength of information flow between presynaptic and postsynaptic neurons and thus modifies the likelihood that action potentials in a presynaptic neuron will lead to an action potential in a postsynaptic neuron. As such, synaptic plasticity and pathological changes in synaptic plasticity impact the synaptic computation which controls the information flow through the neural microcircuits responsible for the complex information processing necessary to drive adaptive behaviors. As current theories of neuropsychiatric disease suggest that distinct dysfunctions in neural circuit performance may critically underlie the unique symptoms of these diseases, pathological alterations in synaptic plasticity mechanisms may be fundamental to the disease process. Here we consider mechanisms of both short-term and long-term plasticity of synaptic transmission and their possible roles in information processing by neural microcircuits in both health and disease. As paradigms of neuropsychiatric diseases with strongly implicated risk genes, we discuss the findings in schizophrenia and autism and consider the alterations in synaptic plasticity and network function observed in both human studies and genetic mouse models of these diseases. Together these studies have begun to point toward a likely dominant role of short-term synaptic plasticity alterations in schizophrenia while dysfunction in autism spectrum disorders (ASDs) may be due to a combination of both short-term and long-term synaptic plasticity alterations. PMID:25505409

  14. Unsupervised discrimination of patterns in spiking neural networks with excitatory and inhibitory synaptic plasticity

    PubMed Central

    Srinivasa, Narayan; Cho, Youngkwan

    2014-01-01

    A spiking neural network model is described for learning to discriminate among spatial patterns in an unsupervised manner. The network anatomy consists of source neurons that are activated by external inputs, a reservoir that resembles a generic cortical layer with an excitatory-inhibitory (EI) network and a sink layer of neurons for readout. Synaptic plasticity in the form of STDP is imposed on all the excitatory and inhibitory synapses at all times. While long-term excitatory STDP enables sparse and efficient learning of the salient features in inputs, inhibitory STDP enables this learning to be stable by establishing a balance between excitatory and inhibitory currents at each neuron in the network. The synaptic weights between source and reservoir neurons form a basis set for the input patterns. The neural trajectories generated in the reservoir due to input stimulation and lateral connections between reservoir neurons can be readout by the sink layer neurons. This activity is used for adaptation of synapses between reservoir and sink layer neurons. A new measure called the discriminability index (DI) is introduced to compute if the network can discriminate between old patterns already presented in an initial training session. The DI is also used to compute if the network adapts to new patterns without losing its ability to discriminate among old patterns. The final outcome is that the network is able to correctly discriminate between all patterns—both old and new. This result holds as long as inhibitory synapses employ STDP to continuously enable current balance in the network. The results suggest a possible direction for future investigation into how spiking neural networks could address the stability-plasticity question despite having continuous synaptic plasticity. PMID:25566045

  15. Histone Deacetylase (HDAC) Inhibitors - Emerging Roles in Neuronal Memory, Learning, Synaptic Plasticity and Neural Regeneration

    PubMed Central

    Ahmad Ganai, Shabir; Ramadoss, Mahalakshmi; Mahadevan, Vijayalakshmi

    2016-01-01

    Epigenetic regulation of neuronal signalling through histone acetylation dictates transcription programs that govern neuronal memory, plasticity and learning paradigms. Histone Acetyl Transferases (HATs) and Histone Deacetylases (HDACs) are antagonistic enzymes that regulate gene expression through acetylation and deacetylation of histone proteins around which DNA is wrapped inside a eukaryotic cell nucleus. The epigenetic control of HDACs and the cellular imbalance between HATs and HDACs dictate disease states and have been implicated in muscular dystrophy, loss of memory, neurodegeneration and autistic disorders. Altering gene expression profiles through inhibition of HDACs is now emerging as a powerful technique in therapy. This review presents evolving applications of HDAC inhibitors as potential drugs in neurological research and therapy. Mechanisms that govern their expression profiles in neuronal signalling, plasticity and learning will be covered. Promising and exciting possibilities of HDAC inhibitors in memory formation, fear conditioning, ischemic stroke and neural regeneration have been detailed. PMID:26487502

  16. Histone Deacetylase (HDAC) Inhibitors - emerging roles in neuronal memory, learning, synaptic plasticity and neural regeneration.

    PubMed

    Ganai, Shabir Ahmad; Ramadoss, Mahalakshmi; Mahadevan, Vijayalakshmi

    2016-01-01

    Epigenetic regulation of neuronal signalling through histone acetylation dictates transcription programs that govern neuronal memory, plasticity and learning paradigms. Histone Acetyl Transferases (HATs) and Histone Deacetylases (HDACs) are antagonistic enzymes that regulate gene expression through acetylation and deacetylation of histone proteins around which DNA is wrapped inside a eukaryotic cell nucleus. The epigenetic control of HDACs and the cellular imbalance between HATs and HDACs dictate disease states and have been implicated in muscular dystrophy, loss of memory, neurodegeneration and autistic disorders. Altering gene expression profiles through inhibition of HDACs is now emerging as a powerful technique in therapy. This review presents evolving applications of HDAC inhibitors as potential drugs in neurological research and therapy. Mechanisms that govern their expression profiles in neuronal signalling, plasticity and learning will be covered. Promising and exciting possibilities of HDAC inhibitors in memory formation, fear conditioning, ischemic stroke and neural regeneration have been detailed. PMID:26487502

  17. Self-organized noise resistance of oscillatory neural networks with spike timing-dependent plasticity

    PubMed Central

    Popovych, Oleksandr V.; Yanchuk, Serhiy; Tass, Peter A.

    2013-01-01

    Intuitively one might expect independent noise to be a powerful tool for desynchronizing a population of synchronized neurons. We here show that, intriguingly, for oscillatory neural populations with adaptive synaptic weights governed by spike timing-dependent plasticity (STDP) the opposite is true. We found that the mean synaptic coupling in such systems increases dynamically in response to the increase of the noise intensity, and there is an optimal noise level, where the amount of synaptic coupling gets maximal in a resonance-like manner as found for the stochastic or coherence resonances, although the mechanism in our case is different. This constitutes a noise-induced self-organization of the synaptic connectivity, which effectively counteracts the desynchronizing impact of independent noise over a wide range of the noise intensity. Given the attempts to counteract neural synchrony underlying tinnitus with noisers and maskers, our results may be of clinical relevance. PMID:24113385

  18. Self-organized noise resistance of oscillatory neural networks with spike timing-dependent plasticity

    NASA Astrophysics Data System (ADS)

    Popovych, Oleksandr V.; Yanchuk, Serhiy; Tass, Peter A.

    2013-10-01

    Intuitively one might expect independent noise to be a powerful tool for desynchronizing a population of synchronized neurons. We here show that, intriguingly, for oscillatory neural populations with adaptive synaptic weights governed by spike timing-dependent plasticity (STDP) the opposite is true. We found that the mean synaptic coupling in such systems increases dynamically in response to the increase of the noise intensity, and there is an optimal noise level, where the amount of synaptic coupling gets maximal in a resonance-like manner as found for the stochastic or coherence resonances, although the mechanism in our case is different. This constitutes a noise-induced self-organization of the synaptic connectivity, which effectively counteracts the desynchronizing impact of independent noise over a wide range of the noise intensity. Given the attempts to counteract neural synchrony underlying tinnitus with noisers and maskers, our results may be of clinical relevance.

  19. Predispositions and plasticity in music and speech learning: neural correlates and implications.

    PubMed

    Zatorre, Robert J

    2013-11-01

    Speech and music are remarkable aspects of human cognition and sensory-motor processing. Cognitive neuroscience has focused on them to understand how brain function and structure are modified by learning. Recent evidence indicates that individual differences in anatomical and functional properties of the neural architecture also affect learning and performance in these domains. Here, neuroimaging findings are reviewed that reiterate evidence of experience-dependent brain plasticity, but also point to the predictive validity of such data in relation to new learning in speech and music domains. Indices of neural sensitivity to certain stimulus features have been shown to predict individual rates of learning; individual network properties of brain activity are especially relevant in this regard, as they may reflect anatomical connectivity. Similarly, numerous studies have shown that anatomical features of auditory cortex and other structures, and their anatomical connectivity, are predictive of new sensory-motor learning ability. Implications of this growing body of literature are discussed. PMID:24179219

  20. Different propagation speeds of recalled sequences in plastic spiking neural networks

    NASA Astrophysics Data System (ADS)

    Huang, Xuhui; Zheng, Zhigang; Hu, Gang; Wu, Si; Rasch, Malte J.

    2015-03-01

    Neural networks can generate spatiotemporal patterns of spike activity. Sequential activity learning and retrieval have been observed in many brain areas, and e.g. is crucial for coding of episodic memory in the hippocampus or generating temporal patterns during song production in birds. In a recent study, a sequential activity pattern was directly entrained onto the neural activity of the primary visual cortex (V1) of rats and subsequently successfully recalled by a local and transient trigger. It was observed that the speed of activity propagation in coordinates of the retinotopically organized neural tissue was constant during retrieval regardless how the speed of light stimulation sweeping across the visual field during training was varied. It is well known that spike-timing dependent plasticity (STDP) is a potential mechanism for embedding temporal sequences into neural network activity. How training and retrieval speeds relate to each other and how network and learning parameters influence retrieval speeds, however, is not well described. We here theoretically analyze sequential activity learning and retrieval in a recurrent neural network with realistic synaptic short-term dynamics and STDP. Testing multiple STDP rules, we confirm that sequence learning can be achieved by STDP. However, we found that a multiplicative nearest-neighbor (NN) weight update rule generated weight distributions and recall activities that best matched the experiments in V1. Using network simulations and mean-field analysis, we further investigated the learning mechanisms and the influence of network parameters on recall speeds. Our analysis suggests that a multiplicative STDP rule with dominant NN spike interaction might be implemented in V1 since recall speed was almost constant in an NMDA-dominant regime. Interestingly, in an AMPA-dominant regime, neural circuits might exhibit recall speeds that instead follow the change in stimulus speeds. This prediction could be tested in

  1. Nogo Receptor Signaling Restricts Adult Neural Plasticity by Limiting Synaptic AMPA Receptor Delivery

    PubMed Central

    Jitsuki, Susumu; Nakajima, Waki; Takemoto, Kiwamu; Sano, Akane; Tada, Hirobumi; Takahashi-Jitsuki, Aoi; Takahashi, Takuya

    2016-01-01

    Experience-dependent plasticity is limited in the adult brain, and its molecular and cellular mechanisms are poorly understood. Removal of the myelin-inhibiting signaling protein, Nogo receptor (NgR1), restores adult neural plasticity. Here we found that, in NgR1-deficient mice, whisker experience-driven synaptic α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor (AMPAR) insertion in the barrel cortex, which is normally complete by 2 weeks after birth, lasts into adulthood. In vivo live imaging by two-photon microscopy revealed more AMPAR on the surface of spines in the adult barrel cortex of NgR1-deficient than on those of wild-type (WT) mice. Furthermore, we observed that whisker stimulation produced new spines in the adult barrel cortex of mutant but not WT mice, and that the newly synthesized spines contained surface AMPAR. These results suggest that Nogo signaling limits plasticity by restricting synaptic AMPAR delivery in coordination with anatomical plasticity. PMID:26472557

  2. STAT3 signal that mediates the neural plasticity is involved in willed-movement training in focal ischemic rats*

    PubMed Central

    Tang, Qing-ping; Shen, Qin; Wu, Li-xiang; Feng, Xiang-ling; Liu, Hui; Wu, Bei; Huang, Xiao-song; Wang, Gai-qing; Li, Zhong-hao; Liu, Zun-jing

    2016-01-01

    Willed-movement training has been demonstrated to be a promising approach to increase motor performance and neural plasticity in ischemic rats. However, little is known regarding the molecular signals that are involved in neural plasticity following willed-movement training. To investigate the potential signals related to neural plasticity following willed-movement training, littermate rats were randomly assigned into three groups: middle cerebral artery occlusion, environmental modification, and willed-movement training. The infarct volume was measured 18 d after occlusion of the right middle cerebral artery. Reverse transcription-polymerase chain reaction (PCR) and immunofluorescence staining were used to detect the changes in the signal transducer and activator of transcription 3 (STAT3) mRNA and protein, respectively. A chromatin immunoprecipitation was used to investigate whether STAT3 bound to plasticity-related genes, such as brain-derived neurotrophic factor (BDNF), synaptophysin, and protein interacting with C kinase 1 (PICK1). In this study, we demonstrated that STAT3 mRNA and protein were markedly increased following 15-d willed-movement training in the ischemic hemispheres of the treated rats. STAT3 bound to BDNF, PICK1, and synaptophysin promoters in the neocortical cells of rats. These data suggest that the increased STAT3 levels after willed-movement training might play critical roles in the neural plasticity by directly regulating plasticity-related genes. PMID:27381726

  3. STAT3 signal that mediates the neural plasticity is involved in willed-movement training in focal ischemic rats.

    PubMed

    Tang, Qing-Ping; Shen, Qin; Wu, Li-Xiang; Feng, Xiang-Ling; Liu, Hui; Wu, Bei; Huang, Xiao-Song; Wang, Gai-Qing; Li, Zhong-Hao; Liu, Zun-Jing

    2016-07-01

    Willed-movement training has been demonstrated to be a promising approach to increase motor performance and neural plasticity in ischemic rats. However, little is known regarding the molecular signals that are involved in neural plasticity following willed-movement training. To investigate the potential signals related to neural plasticity following willed-movement training, littermate rats were randomly assigned into three groups: middle cerebral artery occlusion, environmental modification, and willed-movement training. The infarct volume was measured 18 d after occlusion of the right middle cerebral artery. Reverse transcription-polymerase chain reaction (PCR) and immunofluorescence staining were used to detect the changes in the signal transducer and activator of transcription 3 (STAT3) mRNA and protein, respectively. A chromatin immunoprecipitation was used to investigate whether STAT3 bound to plasticity-related genes, such as brain-derived neurotrophic factor (BDNF), synaptophysin, and protein interacting with C kinase 1 (PICK1). In this study, we demonstrated that STAT3 mRNA and protein were markedly increased following 15-d willed-movement training in the ischemic hemispheres of the treated rats. STAT3 bound to BDNF, PICK1, and synaptophysin promoters in the neocortical cells of rats. These data suggest that the increased STAT3 levels after willed-movement training might play critical roles in the neural plasticity by directly regulating plasticity-related genes. PMID:27381726

  4. Pushing the Limits: Cognitive, Affective, and Neural Plasticity Revealed by an Intensive Multifaceted Intervention.

    PubMed

    Mrazek, Michael D; Mooneyham, Benjamin W; Mrazek, Kaita L; Schooler, Jonathan W

    2016-01-01

    Scientific understanding of how much the adult brain can be shaped by experience requires examination of how multiple influences combine to elicit cognitive, affective, and neural plasticity. Using an intensive multifaceted intervention, we discovered that substantial and enduring improvements can occur in parallel across multiple cognitive and neuroimaging measures in healthy young adults. The intervention elicited substantial improvements in physical health, working memory, standardized test performance, mood, self-esteem, self-efficacy, mindfulness, and life satisfaction. Improvements in mindfulness were associated with increased degree centrality of the insula, greater functional connectivity between insula and somatosensory cortex, and reduced functional connectivity between posterior cingulate cortex (PCC) and somatosensory cortex. Improvements in working memory and reading comprehension were associated with increased degree centrality of a region within the middle temporal gyrus (MTG) that was extensively and predominately integrated with the executive control network. The scope and magnitude of the observed improvements represent the most extensive demonstration to date of the considerable human capacity for change. These findings point to higher limits for rapid and concurrent cognitive, affective, and neural plasticity than is widely assumed. PMID:27047361

  5. Pushing the Limits: Cognitive, Affective, and Neural Plasticity Revealed by an Intensive Multifaceted Intervention

    PubMed Central

    Mrazek, Michael D.; Mooneyham, Benjamin W.; Mrazek, Kaita L.; Schooler, Jonathan W.

    2016-01-01

    Scientific understanding of how much the adult brain can be shaped by experience requires examination of how multiple influences combine to elicit cognitive, affective, and neural plasticity. Using an intensive multifaceted intervention, we discovered that substantial and enduring improvements can occur in parallel across multiple cognitive and neuroimaging measures in healthy young adults. The intervention elicited substantial improvements in physical health, working memory, standardized test performance, mood, self-esteem, self-efficacy, mindfulness, and life satisfaction. Improvements in mindfulness were associated with increased degree centrality of the insula, greater functional connectivity between insula and somatosensory cortex, and reduced functional connectivity between posterior cingulate cortex (PCC) and somatosensory cortex. Improvements in working memory and reading comprehension were associated with increased degree centrality of a region within the middle temporal gyrus (MTG) that was extensively and predominately integrated with the executive control network. The scope and magnitude of the observed improvements represent the most extensive demonstration to date of the considerable human capacity for change. These findings point to higher limits for rapid and concurrent cognitive, affective, and neural plasticity than is widely assumed. PMID:27047361

  6. Upper Limb Immobilisation: A Neural Plasticity Model with Relevance to Poststroke Motor Rehabilitation

    PubMed Central

    Furlan, Leonardo; Conforto, Adriana Bastos; Cohen, Leonardo G.; Sterr, Annette

    2016-01-01

    Advances in our understanding of the neural plasticity that occurs after hemiparetic stroke have contributed to the formulation of theories of poststroke motor recovery. These theories, in turn, have underpinned contemporary motor rehabilitation strategies for treating motor deficits after stroke, such as upper limb hemiparesis. However, a relative drawback has been that, in general, these strategies are most compatible with the recovery profiles of relatively high-functioning stroke survivors and therefore do not easily translate into benefit to those individuals sustaining low-functioning upper limb hemiparesis, who otherwise have poorer residual function. For these individuals, alternative motor rehabilitation strategies are currently needed. In this paper, we will review upper limb immobilisation studies that have been conducted with healthy adult humans and animals. Then, we will discuss how the findings from these studies could inspire the creation of a neural plasticity model that is likely to be of particular relevance to the context of motor rehabilitation after stroke. For instance, as will be elaborated, such model could contribute to the development of alternative motor rehabilitation strategies for treating poststroke upper limb hemiparesis. The implications of the findings from those immobilisation studies for contemporary motor rehabilitation strategies will also be discussed and perspectives for future research in this arena will be provided as well. PMID:26843992

  7. Learning to Produce Syllabic Speech Sounds via Reward-Modulated Neural Plasticity

    PubMed Central

    Warlaumont, Anne S.; Finnegan, Megan K.

    2016-01-01

    At around 7 months of age, human infants begin to reliably produce well-formed syllables containing both consonants and vowels, a behavior called canonical babbling. Over subsequent months, the frequency of canonical babbling continues to increase. How the infant’s nervous system supports the acquisition of this ability is unknown. Here we present a computational model that combines a spiking neural network, reinforcement-modulated spike-timing-dependent plasticity, and a human-like vocal tract to simulate the acquisition of canonical babbling. Like human infants, the model’s frequency of canonical babbling gradually increases. The model is rewarded when it produces a sound that is more auditorily salient than sounds it has previously produced. This is consistent with data from human infants indicating that contingent adult responses shape infant behavior and with data from deaf and tracheostomized infants indicating that hearing, including hearing one’s own vocalizations, is critical for canonical babbling development. Reward receipt increases the level of dopamine in the neural network. The neural network contains a reservoir with recurrent connections and two motor neuron groups, one agonist and one antagonist, which control the masseter and orbicularis oris muscles, promoting or inhibiting mouth closure. The model learns to increase the number of salient, syllabic sounds it produces by adjusting the base level of muscle activation and increasing their range of activity. Our results support the possibility that through dopamine-modulated spike-timing-dependent plasticity, the motor cortex learns to harness its natural oscillations in activity in order to produce syllabic sounds. It thus suggests that learning to produce rhythmic mouth movements for speech production may be supported by general cortical learning mechanisms. The model makes several testable predictions and has implications for our understanding not only of how syllabic vocalizations develop

  8. Learning to Produce Syllabic Speech Sounds via Reward-Modulated Neural Plasticity.

    PubMed

    Warlaumont, Anne S; Finnegan, Megan K

    2016-01-01

    At around 7 months of age, human infants begin to reliably produce well-formed syllables containing both consonants and vowels, a behavior called canonical babbling. Over subsequent months, the frequency of canonical babbling continues to increase. How the infant's nervous system supports the acquisition of this ability is unknown. Here we present a computational model that combines a spiking neural network, reinforcement-modulated spike-timing-dependent plasticity, and a human-like vocal tract to simulate the acquisition of canonical babbling. Like human infants, the model's frequency of canonical babbling gradually increases. The model is rewarded when it produces a sound that is more auditorily salient than sounds it has previously produced. This is consistent with data from human infants indicating that contingent adult responses shape infant behavior and with data from deaf and tracheostomized infants indicating that hearing, including hearing one's own vocalizations, is critical for canonical babbling development. Reward receipt increases the level of dopamine in the neural network. The neural network contains a reservoir with recurrent connections and two motor neuron groups, one agonist and one antagonist, which control the masseter and orbicularis oris muscles, promoting or inhibiting mouth closure. The model learns to increase the number of salient, syllabic sounds it produces by adjusting the base level of muscle activation and increasing their range of activity. Our results support the possibility that through dopamine-modulated spike-timing-dependent plasticity, the motor cortex learns to harness its natural oscillations in activity in order to produce syllabic sounds. It thus suggests that learning to produce rhythmic mouth movements for speech production may be supported by general cortical learning mechanisms. The model makes several testable predictions and has implications for our understanding not only of how syllabic vocalizations develop in

  9. Habituation and extinction of fear recruit overlapping forebrain structures.

    PubMed

    Furlong, Teri M; Richardson, Rick; McNally, Gavan P

    2016-02-01

    Establishing the neurocircuitry involved in inhibiting fear is important for understanding and treating anxiety disorders. To date, extinction procedures have been predominately used to examine the inhibition of learned fear, where fear is reduced to a conditioned stimulus (CS) by presenting it in the absence of the unconditioned stimulus (US). However, learned fear can also be reduced by habituation procedures where the US is presented in the absence of the CS. Here we used expression of the activity marker c-Fos in rats to compare the recruitment of several forebrain structures following fear habituation and extinction. Following fear conditioning where a tone CS was paired with a loud noise US, fear was then reduced the following day by either presentation of the CS or US alone (i.e. CS extinction or US habituation, respectively). This extinction and habituation training recruited several common structures, including infralimbic cortex, basolateral amygdala, midline thalamus and medial hypothalamus (orexin neurons). Moreover, this overlap was shared when examining the neural correlates of the expression of habituation and extinction, with common recruitment of infralimbic cortex and midline thalamus. However, there were also important differences. Specifically, acquisition of habituation was associated with greater recruitment of prelimbic cortex whereas expression of habituation was associated with greater recruitment of paraventricular thalamus. There was also less recruitment of central amygdala for habituation compared to extinction in the retention phase. These findings indicate that largely overlapping neurocircuitries underlie habituation and fear extinction and imply common mechanisms for reducing fear across different inhibitory treatments. PMID:26690954

  10. The Neural Cell Adhesion Molecule-Derived Peptide FGL Facilitates Long-Term Plasticity in the Dentate Gyrus in Vivo

    ERIC Educational Resources Information Center

    Dallerac, Glenn; Zerwas, Meike; Novikova, Tatiana; Callu, Delphine; Leblanc-Veyrac, Pascale; Bock, Elisabeth; Berezin, Vladimir; Rampon, Claire; Doyere, Valerie

    2011-01-01

    The neural cell adhesion molecule (NCAM) is known to play a role in developmental and structural processes but also in synaptic plasticity and memory of the adult animal. Recently, FGL, a NCAM mimetic peptide that binds to the Fibroblast Growth Factor Receptor 1 (FGFR-1), has been shown to have a beneficial impact on normal memory functioning, as…

  11. Neonatal EEG/sleep state analyses: a complex phenotype of developmental neural plasticity.

    PubMed

    Scher, Mark S; Loparo, Kenneth A

    2009-01-01

    Computer analyses of EEG/sleep states can be used as physiologic biomarkers of developmental neural plasticity. Frequency- and time-dependent signal processing strategies of cerebral and noncerebral measures can help test current theories of neuronal network maturation in terms of segregation and integration of short-distance versus long-distance neuronal connections throughout the neuroaxis. Specific phenotypic expressions of adaptive or maladaptive neuronal connectivity are proposed based on comparisons of whole-brain EEG/sleep resting states between preterm and full-term cohorts when developmental outcome measures are applied. Combined use of neurophysiological datasets with neuroimaging and genetic methodologies define endophenotypes that will more accurately diagnose children at risk for developmental disorders, as well as design appropriate neuroprotective interventions for the individual's age and disease progress. PMID:19546563

  12. Drug dependence as a disorder of neural plasticity: focus on dopamine and glutamate.

    PubMed

    Pulvirenti, L; Diana, M

    2001-01-01

    Drug addiction, as a disease, has grown to reach the level of a social illness. Psychostimulants, opiates, alcohol, nicotine and cannabis abuse affects millions worldwide and virtually all classes of modern society. In spite of the enormous proportions of its spread, intimate neurobiological mechanisms leading to distintictive features of this pathological status, such as craving for the abused substance and loss of control over intake, remain largely obscure and pharmacotherapies sadly unsatisfactory. In the last decade, preclinical and clinical research in this field has made great progress to improve our understanding of the brain mechanisms which form the basis of this illness. The review of recent literature, which represents the focus of the present paper, leads to the emerging consensus that an alteration of physiological mechanisms of neural plasticity within the brain dopamine and glutamate systems may underlie some of the behavioral abnormalities occurring during the dependence cycle. In particular, a reduction of dopamine neuronal activity and glutamate neurotransmission at the level of the ventrotegmental area, after withdrawal from chronic administration of drugs of abuse, may work in concert with alterations in other forebrain areas, such as the nucleus accumbens and the amygdaloid complex. In addition, following prolonged periods of abstinence, even after somatic withdrawal signs have vanished, responsiveness of these systems to drugs of abuse remains abnormal. This suggests that these two neurotransmitters may play a substantial role in the long-lasting, enduring changes typical of the addictive process and may represent ideal targets for pharmacological intervention aimed at normalizing forms of neural plasticity impaired after chronic drug intake. PMID:11392455

  13. A Neural Circuit That Controls Cortical State, Plasticity, and the Gain of Sensory Responses in Mouse

    PubMed Central

    Stryker, Michael P.

    2015-01-01

    Neurons in the visual cortex were first found to be exquisitely selective for particular properties of visual stimuli in anesthetized animals, including mice. Studies of alert mice in an apparatus that allowed them to stand or run revealed that locomotion causes a change in cortical state that dramatically increases the magnitude of responses in neurons of the visual cortex without altering selectivity, effectively changing the gain of sensory responses. Locomotion also dramatically enhances adult plasticity in the recovery from long-term visual deprivation. We have studied the elements and operation of the neural circuit responsible for the enhancement of activity and shown that it enhances plasticity even in mice not free to run. The circuit consists of projections ascending from the midbrain locomotor region (MLR) to the basal forebrain, activating cholinergic and perhaps other projections to excite inhibitory interneurons expressing vasoactive intestinal peptide (VIP) in the visual cortex. VIP cells activated by locomotion inhibit interneurons that express somatostatin (SST), thereby disinhibiting the excitatory principal neurons and allowing them to respond more strongly to effective visual stimuli. These findings reveal in alert animals how the ascending reticular activating system described in anesthetized animals 50 years ago operates to control cortical state. PMID:25948638

  14. Central Sensitization: A Generator of Pain Hypersensitivity by Central Neural Plasticity

    PubMed Central

    Latremoliere, Alban; Woolf, Clifford J.

    2009-01-01

    Central sensitization represents an enhancement in the function of neurons and circuits in nociceptive pathways caused by increases in membrane excitability and synaptic efficacy as well as to reduced inhibition and is a manifestation of the remarkable plasticity of the somatosensory nervous system in response to activity, inflammation, and neural injury. The net effect of central sensitization is to recruit previously subthreshold synaptic inputs to nociceptive neurons, generating an increased or augmented action potential output: a state of facilitation, potentiation, augmentation, or amplification. Central sensitization is responsible for many of the temporal, spatial, and threshold changes in pain sensibility in acute and chronic clinical pain settings and exemplifies the fundamental contribution of the central nervous system to the generation of pain hypersensitivity. Because central sensitization results from changes in the properties of neurons in the central nervous system, the pain is no longer coupled, as acute nociceptive pain is, to the presence, intensity, or duration of noxious peripheral stimuli. Instead, central sensitization produces pain hypersensitivity by changing the sensory response elicited by normal inputs, including those that usually evoke innocuous sensations. Perspective In this article, we review the major triggers that initiate and maintain central sensitization in healthy individuals in response to nociceptor input and in patients with inflammatory and neuropathic pain, emphasizing the fundamental contribution and multiple mechanisms of synaptic plasticity caused by changes in the density, nature, and properties of ionotropic and metabotropic glutamate receptors. PMID:19712899

  15. Chronic pain resolution after a lucid dream: a case for neural plasticity?

    PubMed

    Zappaterra, Mauro; Jim, Lysander; Pangarkar, Sanjog

    2014-03-01

    Chronic pain is often managed using a multidisciplinary, biopsychosocial approach. Interventions targeting the biological, psychological, and social aspects of both the patient and the pain have been demonstrated to provide objective and subjective improvement in chronic pain symptoms. The mechanism by which pain attenuation occurs after these interventions remains to be elucidated. While there is a relatively large body of empirical literature suggesting that functional and structural changes in the peripheral and central nervous systems are key in the development and maintenance of chronic pain states, less is known about changes that take place in the nervous system as a whole after biopsychosocial interventions. Using as a model the unique case of Mr. S, a patient suffering with chronic pain for 22 years who experienced a complete resolution of pain after a lucid dream following 2 years of biopsychosocial treatments, we postulate that central nervous system (CNS) reorganization (i.e., neural plasticity) serves as a possible mechanism for the therapeutic benefit of multidisciplinary treatments, and may set a neural framework for healing, in this case via a lucid dream. PMID:24398162

  16. Triphasic spike-timing-dependent plasticity organizes networks to produce robust sequences of neural activity

    PubMed Central

    Waddington, Amelia; Appleby, Peter A.; De Kamps, Marc; Cohen, Netta

    2012-01-01

    Synfire chains have long been proposed to generate precisely timed sequences of neural activity. Such activity has been linked to numerous neural functions including sensory encoding, cognitive and motor responses. In particular, it has been argued that synfire chains underlie the precise spatiotemporal firing patterns that control song production in a variety of songbirds. Previous studies have suggested that the development of synfire chains requires either initial sparse connectivity or strong topological constraints, in addition to any synaptic learning rules. Here, we show that this necessity can be removed by using a previously reported but hitherto unconsidered spike-timing-dependent plasticity (STDP) rule and activity-dependent excitability. Under this rule the network develops stable synfire chains that possess a non-trivial, scalable multi-layer structure, in which relative layer sizes appear to follow a universal function. Using computational modeling and a coarse grained random walk model, we demonstrate the role of the STDP rule in growing, molding and stabilizing the chain, and link model parameters to the resulting structure. PMID:23162457

  17. Cognitive-affective neural plasticity following active-controlled mindfulness intervention

    PubMed Central

    Allen, Micah; Dietz, Martin; Blair, Karina S.; van Beek, Martijn; Rees, Geraint; Vestergaard-Poulsen, Peter; Lutz, Antoine; Roepstorff, Andreas

    2015-01-01

    Mindfulness meditation is a set of attention-based, regulatory and self-inquiry training regimes. Although the impact of mindfulness meditation training (MT) on self-regulation is well established, the neural mechanisms supporting such plasticity are poorly understood. MT is thought to act on attention through interoceptive salience and attentional control mechanisms, but until now conflicting evidence from behavioral and neural measures has made it difficult to distinguish the role of these mechanisms. To resolve this question we conducted a fully randomized 6-week longitudinal trial of MT, explicitly controlling for cognitive and treatment effects with an active control group. We measured behavioral metacognition and whole-brain Blood Oxygenation Level Dependent (BOLD) signals using functional MRI during an affective Stroop task before and after intervention. Although both groups improved significantly on a response-inhibition task, only the MT group showed reduced affective Stroop conflict. Moreover, the MT group displayed greater dorsolateral prefrontal cortex (DLPFC) responses during executive processing, consistent with increased recruitment of top-down mechanisms to resolve conflict. In contrast, we did not observe overall group by time interactions on negative affect-related RTs or BOLD responses. However, only participants with the greatest amount of MT practice showed improvements in response-inhibition and increased recruitment of dorsal anterior cingulate cortex (dACC), medial prefrontal cortex (mPFC), and right anterior insula during negative valence processing. Collectively our findings highlight the importance of active control in MT research, and indicate unique neural mechanisms for progressive stages of mindfulness training. PMID:23115195

  18. Self-organization of feed-forward structure and entrainment in excitatory neural networks with spike-timing-dependent plasticity

    NASA Astrophysics Data System (ADS)

    Takahashi, Yuko K.; Kori, Hiroshi; Masuda, Naoki

    2009-05-01

    Spike-timing dependent plasticity (STDP) is an organizing principle of biological neural networks. While synchronous firing of neurons is considered to be an important functional block in the brain, how STDP shapes neural networks possibly toward synchrony is not entirely clear. We examine relations between STDP and synchronous firing in spontaneously firing neural populations. Using coupled heterogeneous phase oscillators placed on initial networks, we show numerically that STDP prunes some synapses and promotes formation of a feedforward network. Eventually a pacemaker, which is the neuron with the fastest inherent frequency in our numerical simulations, emerges at the root of the feedforward network. In each oscillatory cycle, a packet of neural activity is propagated from the pacemaker to downstream neurons along layers of the feedforward network. This event occurs above a clear-cut threshold value of the initial synaptic weight. Below the threshold, neurons are self-organized into separate clusters each of which is a feedforward network.

  19. The Neural Plasticity Theory of Depression: Assessing the Roles of Adult Neurogenesis and PSA-NCAM within the Hippocampus

    PubMed Central

    Wainwright, Steven R.; Galea, Liisa A. M.

    2013-01-01

    Depression is a devastating and prevalent disease, with profound effects on neural structure and function; however the etiology and neuropathology of depression remain poorly understood. Though antidepressant drugs exist, they are not ideal, as only a segment of patients are effectively treated, therapeutic onset is delayed, and the exact mechanism of these drugs remains to be elucidated. Several theories of depression do exist, including modulation of monoaminergic neurotransmission, alterations in neurotrophic factors, and the upregulation of adult hippocampal neurogenesis, and are briefly mentioned in the review. However none of these theories sufficiently explains the pathology and treatment of depression unto itself. Recently, neural plasticity theories of depression have postulated that multiple aspects of brain plasticity, beyond neurogenesis, may bridge the prevailing theories. The term “neural plasticity” encompasses an array of mechanisms, from the birth, survival, migration, and integration of new neurons to neurite outgrowth, synaptogenesis, and the modulation of mature synapses. This review critically assesses the role of adult hippocampal neurogenesis and the cell adhesion molecule, PSA-NCAM (which is known to be involved in many facets of neural plasticity), in depression and antidepressant treatment. PMID:23691371

  20. Child Abuse, Depression, and Methylation in Genes Involved with Stress, Neural Plasticity, and Brain Circuitry

    PubMed Central

    Weder, Natalie; Zhang, Huiping; Jensen, Kevin; Yang, Bao Zhu; Simen, Arthur; Jackowski, Andrea; Lipschitz, Deborah; Douglas-Palumberi, Heather; Ge, Margrat; Perepletchikova, Francheska; O’Laughlin, Kerry; Hudziak, James J.; Gelernter, Joel; Kaufman, Joan

    2014-01-01

    Objectives Determine if epigenetic markers predict dimensional ratings of depression in maltreated children. Method A Genome-wide methylation study was completed using the Illumina 450K BeadChip array in 94 maltreated and 96 non-traumatized children with saliva-derived DNA. The 450K BeadChip does not include any methylation sites in the exact location as sites in candidate genes previously examined in the literature, so a test for replication of prior research findings was not feasible. Results Methylation in three genes emerged as genomewide-significant predictors of depression: DNA-Binding Protein Inhibitor ID-3 (ID3); Glutamate Receptor, Ionotropic NMDA 1 (GRIN1); and Tubulin Polymerization Promoting Protein (TPPP) (p<5.0 × 10−7, all analyses). These genes are all biologically relevant–with ID3 involved in the stress response, GRIN1 involved in neural plasticity, and TPPP involved in neural circuitry development. Methylation in CpG sites in candidate genes were not predictors of depression at significance levels corrected for whole genome testing, but maltreated and control children did have significantly different beta values after Bonferroni correction at multiple methylation sites in these candidate genes (e.g., BDNF, NR3C1, FKBP5). Conclusion This study suggests epigenetic changes in ID3, GRIN1, and TPPP genes, in combination with experiences of maltreatment, may confer risk for depression in children. It adds to a growing body of literature supporting a role for epigenetic mechanisms in the pathophysiology of stress-related psychiatric disorders. While epigenetic changes are frequently long lasting, they are not necessarily permanent. Consequently, interventions to reverse the negative biological and behavioral sequelae associated with child maltreatment are briefly discussed. PMID:24655651

  1. Sex Differences in Fetal Habituation

    ERIC Educational Resources Information Center

    Hepper, Peter G.; Dornan, James C.; Lynch, Catherine

    2012-01-01

    There is some evidence for sex differences in habituation in the human fetus, but it is unknown whether this is due to differences in central processing (habituation) or in more peripheral processes, sensory or motor, involved in the response. This study examined whether the sex of the fetus influenced auditory habituation at 33 weeks of…

  2. Structure and plasticity potential of neural networks in the cerebral cortex

    NASA Astrophysics Data System (ADS)

    Fares, Tarec Edmond

    In this thesis, we first described a theoretical framework for the analysis of spine remodeling plasticity. We provided a quantitative description of two models of spine remodeling in which the presence of a bouton is either required or not for the formation of a new synapse. We derived expressions for the density of potential synapses in the neuropil, the connectivity fraction, which is the ratio of actual to potential synapses, and the number of structurally different circuits attainable with spine remodeling. We calculated these parameters in mouse occipital cortex, rat CA1, monkey V1, and human temporal cortex. We found that on average a dendritic spine can choose among 4-7 potential targets in rodents and 10-20 potential targets in primates. The neuropil's potential for structural circuit remodeling is highest in rat CA1 (7.1-8.6 bits/mum3) and lowest in monkey V1 (1.3-1.5 bits/mum 3 We next studied the role neuron morphology plays in defining synaptic connectivity. As previously stated it is clear that only pairs of neurons with closely positioned axonal and dendritic branches can be synaptically coupled. For excitatory neurons in the cerebral cortex, ). We also evaluated the lower bound of neuron selectivity in the choice of synaptic partners. Post-synaptic excitatory neurons in rodents make synaptic contacts with more than 21-30% of pre-synaptic axons encountered with new spine growth. Primate neurons appear to be more selective, making synaptic connections with more than 7-15% of encountered axons. We next studied the role neuron morphology plays in defining synaptic connectivity. As previously stated it is clear that only pairs of neurons with closely positioned axonal and dendritic branches can be synaptically coupled. For excitatory neurons in the cerebral cortex, such axo-dendritic oppositions, or potential synapses, must be bridged by dendritic spines to form synaptic connections. To explore the rules by which synaptic connections are formed within

  3. Examining neural plasticity and cognitive benefit through the unique lens of musical training.

    PubMed

    Moreno, Sylvain; Bidelman, Gavin M

    2014-02-01

    Training programs aimed to alleviate or improve auditory-cognitive abilities have either experienced mixed success or remain to be fully validated. The limited benefits of such regimens are largely attributable to our weak understanding of (i) how (and which) interventions provide the most robust and long lasting improvements to cognitive and perceptual abilities and (ii) how the neural mechanisms which underlie such abilities are positively modified by certain activities and experience. Recent studies indicate that music training provides robust, long-lasting biological benefits to auditory function. Importantly, the behavioral advantages conferred by musical experience extend beyond simple enhancements to perceptual abilities and even impact non-auditory functions necessary for higher-order aspects of cognition (e.g., working memory, intelligence). Collectively, preliminary findings indicate that alternative forms of arts engagement (e.g., visual arts training) may not yield such widespread enhancements, suggesting that music expertise uniquely taps and refines a hierarchy of brain networks subserving a variety of auditory as well as domain-general cognitive mechanisms. We infer that transfer from specific music experience to broad cognitive benefit might be mediated by the degree to which a listener's musical training tunes lower- (e.g., perceptual) and higher-order executive functions, and the coordination between these processes. Ultimately, understanding the broad impact of music on the brain will not only provide a more holistic picture of auditory processing and plasticity, but may help inform and tailor remediation and training programs designed to improve perceptual and cognitive benefits in human listeners. PMID:24079993

  4. Mechanisms of plasticity in a Caenorhabditis elegans mechanosensory circuit

    PubMed Central

    Bozorgmehr, Tahereh; Ardiel, Evan L.; McEwan, Andrea H.; Rankin, Catharine H.

    2012-01-01

    Despite having a small nervous system (302 neurons) and relatively short lifespan (14–21 days), the nematode Caenorhabditis elegans has a substantial ability to change its behavior in response to experience. The behavior discussed here is the tap withdrawal response, whereby the worm crawls backwards a brief distance in response to a non-localized mechanosensory stimulus from a tap to the side of the Petri plate within which it lives. The neural circuit that underlies this behavior is primarily made up of five sensory neurons and four pairs of interneurons. In this review we describe two classes of mechanosensory plasticity: adult learning and memory and experience dependent changes during development. As worms develop through young adult and adult stages there is a shift toward deeper habituation of response probability that is likely the result of changes in sensitivity to stimulus intensity. Adult worms show short- intermediate- and long-term habituation as well as context dependent habituation. Short-term habituation requires glutamate signaling and auto-phosphorylation of voltage-dependent potassium channels and is modulated by dopamine signaling in the mechanosensory neurons. Long-term memory (LTM) for habituation is mediated by down-regulation of expression of an AMPA-type glutamate receptor subunit. Intermediate memory involves an increase in release of an inhibitory neuropeptide. Depriving larval worms of mechanosensory stimulation early in development leads to fewer synaptic vesicles in the mechanosensory neurons and lower levels of an AMPA-type glutamate receptor subunit in the interneurons. Overall, the mechanosensory system of C. elegans shows a great deal of experience dependent plasticity both during development and as an adult. The simplest form of learning, habituation, is not so simple and is mediated and/or modulated by a number of different processes, some of which we are beginning to understand. PMID:23986713

  5. Protein kinase C substrate phosphorylation in relation to neural growth and synaptic plasticity: a common molecular mechanism underlying multiple neural functions

    SciTech Connect

    Nelson, R.B.

    1987-01-01

    In these studies, we addressed the issues of: (1) whether neural protein kinase C (PKC) substrates might be altered in phosphorylation following induction of long-term potentiation (LTP); (2) whether PKC substrate phosphorylation might be specifically related to a model of neural plasticity other than LTP; and (3) whether the PKC substrates implicated in adult synaptic plasticity might be present in axonal growth cones given reports that high concentrations of PKC are found in these structures. Using quantitative analysis of multiple two-dimensional gels, we found that the two major substrates of exogenous purified PKC in adult hippocampal homogenate are both directly correlated to persistence of LTP. In rhesus monkey cerebral cortex, the proteins corresponding to protein F1 and 80k displayed topographical gradients in /sup 32/P-incorporation along the occipitotemporal visual processing pathway. The phosphorylation of both proteins was 11- and 14-fold higher, respectively, in temporal regions of this pathway implicated in the storage of visual representations, than in occipital regions, which do not appear to directly participate in visual memory functions.

  6. Diverse synaptic plasticity mechanisms orchestrated to form and retrieve memories in spiking neural networks.

    PubMed

    Zenke, Friedemann; Agnes, Everton J; Gerstner, Wulfram

    2015-01-01

    Synaptic plasticity, the putative basis of learning and memory formation, manifests in various forms and across different timescales. Here we show that the interaction of Hebbian homosynaptic plasticity with rapid non-Hebbian heterosynaptic plasticity is, when complemented with slower homeostatic changes and consolidation, sufficient for assembly formation and memory recall in a spiking recurrent network model of excitatory and inhibitory neurons. In the model, assemblies were formed during repeated sensory stimulation and characterized by strong recurrent excitatory connections. Even days after formation, and despite ongoing network activity and synaptic plasticity, memories could be recalled through selective delay activity following the brief stimulation of a subset of assembly neurons. Blocking any component of plasticity prevented stable functioning as a memory network. Our modelling results suggest that the diversity of plasticity phenomena in the brain is orchestrated towards achieving common functional goals. PMID:25897632

  7. Diverse synaptic plasticity mechanisms orchestrated to form and retrieve memories in spiking neural networks

    PubMed Central

    Zenke, Friedemann; Agnes, Everton J.; Gerstner, Wulfram

    2015-01-01

    Synaptic plasticity, the putative basis of learning and memory formation, manifests in various forms and across different timescales. Here we show that the interaction of Hebbian homosynaptic plasticity with rapid non-Hebbian heterosynaptic plasticity is, when complemented with slower homeostatic changes and consolidation, sufficient for assembly formation and memory recall in a spiking recurrent network model of excitatory and inhibitory neurons. In the model, assemblies were formed during repeated sensory stimulation and characterized by strong recurrent excitatory connections. Even days after formation, and despite ongoing network activity and synaptic plasticity, memories could be recalled through selective delay activity following the brief stimulation of a subset of assembly neurons. Blocking any component of plasticity prevented stable functioning as a memory network. Our modelling results suggest that the diversity of plasticity phenomena in the brain is orchestrated towards achieving common functional goals. PMID:25897632

  8. What Habituates in Infant Visual Habituation? A Psychophysiological Analysis

    ERIC Educational Resources Information Center

    Colombo, John; Shaddy, D. Jill; Anderson, Christa J.; Gibson, Linzi J.; Blaga, Otilia M.; Kannass, Kathleen N.

    2010-01-01

    Despite the use of visual habituation over the past half century, relatively little is known about its underlying processes. We analyzed heart rate (HR) taken simultaneous with looking during infant-controlled habituation sessions collected longitudinally at 4, 6, and 8 months of age with the goal of examining how HR and HR-defined phases of…

  9. Neural plasticity in hypocretin neurons: the basis of hypocretinergic regulation of physiological and behavioral functions in animals

    PubMed Central

    Gao, Xiao-Bing; Hermes, Gretchen

    2015-01-01

    The neuronal system that resides in the perifornical and lateral hypothalamus (Pf/LH) and synthesizes the neuropeptide hypocretin/orexin participates in critical brain functions across species from fish to human. The hypocretin system regulates neural activity responsible for daily functions (such as sleep/wake homeostasis, energy balance, appetite, etc.) and long-term behavioral changes (such as reward seeking and addiction, stress response, etc.) in animals. The most recent evidence suggests that the hypocretin system undergoes substantial plastic changes in response to both daily fluctuations (such as food intake and sleep-wake regulation) and long-term changes (such as cocaine seeking) in neuronal activity in the brain. The understanding of these changes in the hypocretin system is essential in addressing the role of the hypocretin system in normal physiological functions and pathological conditions in animals and humans. In this review, the evidence demonstrating that neural plasticity occurs in hypocretin-containing neurons in the Pf/LH will be presented and possible physiological, behavioral, and mental health implications of these findings will be discussed. PMID:26539086

  10. Neuroticism and conscientiousness respectively constrain and facilitate short-term plasticity within the working memory neural network.

    PubMed

    Dima, Danai; Friston, Karl J; Stephan, Klaas E; Frangou, Sophia

    2015-10-01

    Individual differences in cognitive efficiency, particularly in relation to working memory (WM), have been associated both with personality dimensions that reflect enduring regularities in brain configuration, and with short-term neural plasticity, that reflects task-related changes in brain connectivity. To elucidate the relationship of these two divergent mechanisms, we tested the hypothesis that personality dimensions, which reflect enduring aspects of brain configuration, inform about the neurobiological framework within which short-term, task-related plasticity, as measured by effective connectivity, can be facilitated or constrained. As WM consistently engages the dorsolateral prefrontal (DLPFC), parietal (PAR), and anterior cingulate cortex (ACC), we specified a WM network model with bidirectional, ipsilateral, and contralateral connections between these regions from a functional magnetic resonance imaging dataset obtained from 40 healthy adults while performing the 3-back WM task. Task-related effective connectivity changes within this network were estimated using Dynamic Causal Modelling. Personality was evaluated along the major dimensions of Neuroticism, Extraversion, Openness to Experience, Agreeableness, and Conscientiousness. Only two dimensions were relevant to task-dependent effective connectivity. Neuroticism and Conscientiousness respectively constrained and facilitated neuroplastic responses within the WM network. These results suggest individual differences in cognitive efficiency arise from the interplay between enduring and short-term plasticity in brain configuration. PMID:26189566

  11. Modification of tenascin-R expression following unilateral labyrinthectomy in rats indicates its possible role in neural plasticity of the vestibular neural circuit

    PubMed Central

    Gaal, Botond; Jóhannesson, Einar Örn; Dattani, Amit; Magyar, Agnes; Wéber, Ildikó; Matesz, Clara

    2015-01-01

    We have previously found that unilateral labyrinthectomy is accompanied by modification of hyaluronan and chondroitin sulfate proteoglycan staining in the lateral vestibular nucleus of rats and the time course of subsequent reorganization of extracellular matrix assembly correlates to the restoration of impaired vestibular function. The tenascin-R has repelling effect on pathfinding during axonal growth/regrowth, and thus inhibits neural circuit repair. By using immunohistochemical method, we studied the modification of tenascin-R expression in the superior, medial, lateral, and descending vestibular nuclei of the rat following unilateral labyrinthectomy. On postoperative day 1, tenascin-R reaction in the perineuronal nets disappeared on the side of labyrinthectomy in the superior, lateral, medial, and rostral part of the descending vestibular nuclei. On survival day 3, the staining intensity of tenascin-R reaction in perineuronal nets recovered on the operated side of the medial vestibular nucleus, whereas it was restored by the time of postoperative day 7 in the superior, lateral and rostral part of the descending vestibular nuclei. The staining intensity of tenascin-R reaction remained unchanged in the caudal part of the descending vestibular nucleus bilaterally. Regional differences in the modification of tenascin-R expression presented here may be associated with different roles of individual vestibular nuclei in the compensatory processes. The decreased expression of the tenascin-R may suggest the extracellular facilitation of plastic modifications in the vestibular neural circuit after lesion of the labyrinthine receptors. PMID:26604908

  12. Tinnitus and neural plasticity (Tonndorf lecture at XIth International Tinnitus Seminar, Berlin, 2014).

    PubMed

    Eggermont, Jos J

    2015-01-01

    Ten years ago, animal models of noise-induced hearing loss predicted three cortical neural correlates of tinnitus resulting from noise-induced hearing loss: increased spontaneous firing rates, increased neural synchrony, and reorganization of tonotopic maps. Salicylate also induces tinnitus, however, the cortical correlates were reduced spontaneous firing rates, unchanged neural synchrony but some change to the tonotopic map. In both conditions increased central gain, potentially a correlate of hyperacusis, was found. Behavioral animal models suggested that tinnitus occurred, albeit not in all cases. The study of the neural substrates of tinnitus in humans is currently strongly based on network connectivity using either spontaneous EEG or MEG. Brain imaging combined with powerful analyses is now able to provide in excellent detail the lay out of tonotopic maps, and has shown that in people with tinnitus (and clinical normal hearing up to 8 kHz) no changes in tonotopic maps need to occur, dispensing therefore of one of the postulated neural correlates. Patients with hyperacusis and tinnitus showed increased gain, as measured using fMRI, from brainstem to cortex, whereas patients with tinnitus without hyperacusis only showed this in auditory cortex. This suggested that top down mechanisms are also needed. The open problems can be formulated by the following questions. 1) Are the neural substrates of tinnitus etiology dependent? 2) Can animal results based on single unit and local field potentials be validated in humans? 3) Can sufficient vs. necessary neural substrates for tinnitus be established. 4) What is the role of attention and stress in engraining tinnitus in memory? PMID:25316625

  13. Stable learning of functional maps in self-organizing spiking neural networks with continuous synaptic plasticity

    PubMed Central

    Srinivasa, Narayan; Jiang, Qin

    2013-01-01

    This study describes a spiking model that self-organizes for stable formation and maintenance of orientation and ocular dominance maps in the visual cortex (V1). This self-organization process simulates three development phases: an early experience-independent phase, a late experience-independent phase and a subsequent refinement phase during which experience acts to shape the map properties. The ocular dominance maps that emerge accommodate the two sets of monocular inputs that arise from the lateral geniculate nucleus (LGN) to layer 4 of V1. The orientation selectivity maps that emerge feature well-developed iso-orientation domains and fractures. During the last two phases of development the orientation preferences at some locations appear to rotate continuously through ±180° along circular paths and referred to as pinwheel-like patterns but without any corresponding point discontinuities in the orientation gradient maps. The formation of these functional maps is driven by balanced excitatory and inhibitory currents that are established via synaptic plasticity based on spike timing for both excitatory and inhibitory synapses. The stability and maintenance of the formed maps with continuous synaptic plasticity is enabled by homeostasis caused by inhibitory plasticity. However, a prolonged exposure to repeated stimuli does alter the formed maps over time due to plasticity. The results from this study suggest that continuous synaptic plasticity in both excitatory neurons and interneurons could play a critical role in the formation, stability, and maintenance of functional maps in the cortex. PMID:23450808

  14. Habituation of visual adaptation

    PubMed Central

    Dong, Xue; Gao, Yi; Lv, Lili; Bao, Min

    2016-01-01

    Our sensory system adjusts its function driven by both shorter-term (e.g. adaptation) and longer-term (e.g. learning) experiences. Most past adaptation literature focuses on short-term adaptation. Only recently researchers have begun to investigate how adaptation changes over a span of days. This question is important, since in real life many environmental changes stretch over multiple days or longer. However, the answer to the question remains largely unclear. Here we addressed this issue by tracking perceptual bias (also known as aftereffect) induced by motion or contrast adaptation across multiple daily adaptation sessions. Aftereffects were measured every day after adaptation, which corresponded to the degree of adaptation on each day. For passively viewed adapters, repeated adaptation attenuated aftereffects. Once adapters were presented with an attentional task, aftereffects could either reduce for easy tasks, or initially show an increase followed by a later decrease for demanding tasks. Quantitative analysis of the decay rates in contrast adaptation showed that repeated exposure of the adapter appeared to be equivalent to adaptation to a weaker stimulus. These results suggest that both attention and a non-attentional habituation-like mechanism jointly determine how adaptation develops across multiple daily sessions. PMID:26739917

  15. Habituation of visual adaptation.

    PubMed

    Dong, Xue; Gao, Yi; Lv, Lili; Bao, Min

    2016-01-01

    Our sensory system adjusts its function driven by both shorter-term (e.g. adaptation) and longer-term (e.g. learning) experiences. Most past adaptation literature focuses on short-term adaptation. Only recently researchers have begun to investigate how adaptation changes over a span of days. This question is important, since in real life many environmental changes stretch over multiple days or longer. However, the answer to the question remains largely unclear. Here we addressed this issue by tracking perceptual bias (also known as aftereffect) induced by motion or contrast adaptation across multiple daily adaptation sessions. Aftereffects were measured every day after adaptation, which corresponded to the degree of adaptation on each day. For passively viewed adapters, repeated adaptation attenuated aftereffects. Once adapters were presented with an attentional task, aftereffects could either reduce for easy tasks, or initially show an increase followed by a later decrease for demanding tasks. Quantitative analysis of the decay rates in contrast adaptation showed that repeated exposure of the adapter appeared to be equivalent to adaptation to a weaker stimulus. These results suggest that both attention and a non-attentional habituation-like mechanism jointly determine how adaptation develops across multiple daily sessions. PMID:26739917

  16. Helping the Habitually Late Student.

    ERIC Educational Resources Information Center

    Bergman, Jerry

    1978-01-01

    The author gives three major reasons for a student being habitually late to class: resistance, disorganization, or unavoidable schedule conflicts. He makes specific suggestions to teachers for dealing with the disorganized and resistant latecomers. (SJL)

  17. Habituation and 1/f Noise

    NASA Astrophysics Data System (ADS)

    West, Bruce; Grigolini, Paolo

    2010-03-01

    We present a model to explain the psychophysical phenomena of habituation using methods from non-equilibrium statistical physics and complex network theory. Habituation is a ubiquitous and extremely simple from of learning through which animals, including humans; learn to disregard stimuli that are no longer novel, thereby allowing them to attend to new stimuli.Herein we present a statistical habituation model (SHM) based on a generalization of linear response theory and discrete events using renewal theory. The SHM introduces a theory of the effective synaptic weight connecting two neuron networks, with the synaptic weight being described by a time series with inverse power-law statistics. The statistics determine the distribution of time intervals between events, which in a complex neuronal network leads to neuronal avalanches, see e.g., Beggs and Plenz (J. Neurosci 23, 11167, 2003). The SHM establishes that the fundamental mechanism producing habituation in its myriad of forms is the 1/f-nose that is generically produced in individual neurons and in complex neuronal networks. Both simple harmonic and more complicated stimuli are shown to habituate (decay) as inverse power laws with indices determined by the power-law index of the effective synaptic statistical distribution. This is the first theory that directly relates the psychophysical phenomenon of habituation to the dynamics of the brain.

  18. Learning to Perceive Structure from Motion and Neural Plasticity in Patients with Alzheimer's Disease

    ERIC Educational Resources Information Center

    Kim, Nam-Gyoon; Park, Jong-Hee

    2010-01-01

    Recent research has demonstrated that Alzheimer's disease (AD) affects the visual sensory pathways, producing a variety of visual deficits, including the capacity to perceive structure-from-motion (SFM). Because the sensory areas of the adult brain are known to retain a large degree of plasticity, the present study was conducted to explore whether…

  19. Dissociation of Neural Networks for Predisposition and for Training-Related Plasticity in Auditory-Motor Learning.

    PubMed

    Herholz, Sibylle C; Coffey, Emily B J; Pantev, Christo; Zatorre, Robert J

    2016-07-01

    Skill learning results in changes to brain function, but at the same time individuals strongly differ in their abilities to learn specific skills. Using a 6-week piano-training protocol and pre- and post-fMRI of melody perception and imagery in adults, we dissociate learning-related patterns of neural activity from pre-training activity that predicts learning rates. Fronto-parietal and cerebellar areas related to storage of newly learned auditory-motor associations increased their response following training; in contrast, pre-training activity in areas related to stimulus encoding and motor control, including right auditory cortex, hippocampus, and caudate nuclei, was predictive of subsequent learning rate. We discuss the implications of these results for models of perceptual and of motor learning. These findings highlight the importance of considering individual predisposition in plasticity research and applications. PMID:26139842

  20. Cognitive and neural plasticity in older adults’ prospective memory following training with the Virtual Week computer game

    PubMed Central

    Rose, Nathan S.; Rendell, Peter G.; Hering, Alexandra; Kliegel, Matthias; Bidelman, Gavin M.; Craik, Fergus I. M.

    2015-01-01

    Prospective memory (PM) – the ability to remember and successfully execute our intentions and planned activities – is critical for functional independence and declines with age, yet few studies have attempted to train PM in older adults. We developed a PM training program using the Virtual Week computer game. Trained participants played the game in 12, 1-h sessions over 1 month. Measures of neuropsychological functions, lab-based PM, event-related potentials (ERPs) during performance on a lab-based PM task, instrumental activities of daily living, and real-world PM were assessed before and after training. Performance was compared to both no-contact and active (music training) control groups. PM on the Virtual Week game dramatically improved following training relative to controls, suggesting PM plasticity is preserved in older adults. Relative to control participants, training did not produce reliable transfer to laboratory-based tasks, but was associated with a reduction of an ERP component (sustained negativity over occipito-parietal cortex) associated with processing PM cues, indicative of more automatic PM retrieval. Most importantly, training produced far transfer to real-world outcomes including improvements in performance on real-world PM and activities of daily living. Real-world gains were not observed in either control group. Our findings demonstrate that short-term training with the Virtual Week game produces cognitive and neural plasticity that may result in real-world benefits to supporting functional independence in older adulthood. PMID:26578936

  1. Cognitive and neural plasticity in older adults' prospective memory following training with the Virtual Week computer game.

    PubMed

    Rose, Nathan S; Rendell, Peter G; Hering, Alexandra; Kliegel, Matthias; Bidelman, Gavin M; Craik, Fergus I M

    2015-01-01

    Prospective memory (PM) - the ability to remember and successfully execute our intentions and planned activities - is critical for functional independence and declines with age, yet few studies have attempted to train PM in older adults. We developed a PM training program using the Virtual Week computer game. Trained participants played the game in 12, 1-h sessions over 1 month. Measures of neuropsychological functions, lab-based PM, event-related potentials (ERPs) during performance on a lab-based PM task, instrumental activities of daily living, and real-world PM were assessed before and after training. Performance was compared to both no-contact and active (music training) control groups. PM on the Virtual Week game dramatically improved following training relative to controls, suggesting PM plasticity is preserved in older adults. Relative to control participants, training did not produce reliable transfer to laboratory-based tasks, but was associated with a reduction of an ERP component (sustained negativity over occipito-parietal cortex) associated with processing PM cues, indicative of more automatic PM retrieval. Most importantly, training produced far transfer to real-world outcomes including improvements in performance on real-world PM and activities of daily living. Real-world gains were not observed in either control group. Our findings demonstrate that short-term training with the Virtual Week game produces cognitive and neural plasticity that may result in real-world benefits to supporting functional independence in older adulthood. PMID:26578936

  2. Refinement and Pattern Formation in Neural Circuits by the Interaction of Traveling Waves with Spike-Timing Dependent Plasticity.

    PubMed

    Bennett, James E M; Bair, Wyeth

    2015-08-01

    Traveling waves in the developing brain are a prominent source of highly correlated spiking activity that may instruct the refinement of neural circuits. A candidate mechanism for mediating such refinement is spike-timing dependent plasticity (STDP), which translates correlated activity patterns into changes in synaptic strength. To assess the potential of these phenomena to build useful structure in developing neural circuits, we examined the interaction of wave activity with STDP rules in simple, biologically plausible models of spiking neurons. We derive an expression for the synaptic strength dynamics showing that, by mapping the time dependence of STDP into spatial interactions, traveling waves can build periodic synaptic connectivity patterns into feedforward circuits with a broad class of experimentally observed STDP rules. The spatial scale of the connectivity patterns increases with wave speed and STDP time constants. We verify these results with simulations and demonstrate their robustness to likely sources of noise. We show how this pattern formation ability, which is analogous to solutions of reaction-diffusion systems that have been widely applied to biological pattern formation, can be harnessed to instruct the refinement of postsynaptic receptive fields. Our results hold for rich, complex wave patterns in two dimensions and over several orders of magnitude in wave speeds and STDP time constants, and they provide predictions that can be tested under existing experimental paradigms. Our model generalizes across brain areas and STDP rules, allowing broad application to the ubiquitous occurrence of traveling waves and to wave-like activity patterns induced by moving stimuli. PMID:26308406

  3. Refinement and Pattern Formation in Neural Circuits by the Interaction of Traveling Waves with Spike-Timing Dependent Plasticity

    PubMed Central

    Bennett, James E. M.; Bair, Wyeth

    2015-01-01

    Traveling waves in the developing brain are a prominent source of highly correlated spiking activity that may instruct the refinement of neural circuits. A candidate mechanism for mediating such refinement is spike-timing dependent plasticity (STDP), which translates correlated activity patterns into changes in synaptic strength. To assess the potential of these phenomena to build useful structure in developing neural circuits, we examined the interaction of wave activity with STDP rules in simple, biologically plausible models of spiking neurons. We derive an expression for the synaptic strength dynamics showing that, by mapping the time dependence of STDP into spatial interactions, traveling waves can build periodic synaptic connectivity patterns into feedforward circuits with a broad class of experimentally observed STDP rules. The spatial scale of the connectivity patterns increases with wave speed and STDP time constants. We verify these results with simulations and demonstrate their robustness to likely sources of noise. We show how this pattern formation ability, which is analogous to solutions of reaction-diffusion systems that have been widely applied to biological pattern formation, can be harnessed to instruct the refinement of postsynaptic receptive fields. Our results hold for rich, complex wave patterns in two dimensions and over several orders of magnitude in wave speeds and STDP time constants, and they provide predictions that can be tested under existing experimental paradigms. Our model generalizes across brain areas and STDP rules, allowing broad application to the ubiquitous occurrence of traveling waves and to wave-like activity patterns induced by moving stimuli. PMID:26308406

  4. Learning, neural plasticity and sensitive periods: implications for language acquisition, music training and transfer across the lifespan.

    PubMed

    White, Erin J; Hutka, Stefanie A; Williams, Lynne J; Moreno, Sylvain

    2013-01-01

    Sensitive periods in human development have often been proposed to explain age-related differences in the attainment of a number of skills, such as a second language (L2) and musical expertise. It is difficult to reconcile the negative consequence this traditional view entails for learning after a sensitive period with our current understanding of the brain's ability for experience-dependent plasticity across the lifespan. What is needed is a better understanding of the mechanisms underlying auditory learning and plasticity at different points in development. Drawing on research in language development and music training, this review examines not only what we learn and when we learn it, but also how learning occurs at different ages. First, we discuss differences in the mechanism of learning and plasticity during and after a sensitive period by examining how language exposure versus training forms language-specific phonetic representations in infants and adult L2 learners, respectively. Second, we examine the impact of musical training that begins at different ages on behavioral and neural indices of auditory and motor processing as well as sensorimotor integration. Third, we examine the extent to which childhood training in one auditory domain can enhance processing in another domain via the transfer of learning between shared neuro-cognitive systems. Specifically, we review evidence for a potential bi-directional transfer of skills between music and language by examining how speaking a tonal language may enhance music processing and, conversely, how early music training can enhance language processing. We conclude with a discussion of the role of attention in auditory learning for learning during and after sensitive periods and outline avenues of future research. PMID:24312022

  5. Learning, neural plasticity and sensitive periods: implications for language acquisition, music training and transfer across the lifespan

    PubMed Central

    White, Erin J.; Hutka, Stefanie A.; Williams, Lynne J.; Moreno, Sylvain

    2013-01-01

    Sensitive periods in human development have often been proposed to explain age-related differences in the attainment of a number of skills, such as a second language (L2) and musical expertise. It is difficult to reconcile the negative consequence this traditional view entails for learning after a sensitive period with our current understanding of the brain’s ability for experience-dependent plasticity across the lifespan. What is needed is a better understanding of the mechanisms underlying auditory learning and plasticity at different points in development. Drawing on research in language development and music training, this review examines not only what we learn and when we learn it, but also how learning occurs at different ages. First, we discuss differences in the mechanism of learning and plasticity during and after a sensitive period by examining how language exposure versus training forms language-specific phonetic representations in infants and adult L2 learners, respectively. Second, we examine the impact of musical training that begins at different ages on behavioral and neural indices of auditory and motor processing as well as sensorimotor integration. Third, we examine the extent to which childhood training in one auditory domain can enhance processing in another domain via the transfer of learning between shared neuro-cognitive systems. Specifically, we review evidence for a potential bi-directional transfer of skills between music and language by examining how speaking a tonal language may enhance music processing and, conversely, how early music training can enhance language processing. We conclude with a discussion of the role of attention in auditory learning for learning during and after sensitive periods and outline avenues of future research. PMID:24312022

  6. Reaction-diffusion-like formalism for plastic neural networks reveals dissipative solitons at criticality

    NASA Astrophysics Data System (ADS)

    Grytskyy, Dmytro; Diesmann, Markus; Helias, Moritz

    2016-06-01

    Self-organized structures in networks with spike-timing dependent synaptic plasticity (STDP) are likely to play a central role for information processing in the brain. In the present study we derive a reaction-diffusion-like formalism for plastic feed-forward networks of nonlinear rate-based model neurons with a correlation sensitive learning rule inspired by and being qualitatively similar to STDP. After obtaining equations that describe the change of the spatial shape of the signal from layer to layer, we derive a criterion for the nonlinearity necessary to obtain stable dynamics for arbitrary input. We classify the possible scenarios of signal evolution and find that close to the transition to the unstable regime metastable solutions appear. The form of these dissipative solitons is determined analytically and the evolution and interaction of several such coexistent objects is investigated.

  7. Neural Plasticity following Abacus Training in Humans: A Review and Future Directions.

    PubMed

    Li, Yongxin; Chen, Feiyan; Huang, Wenhua

    2016-01-01

    The human brain has an enormous capacity to adapt to a broad variety of environmental demands. Previous studies in the field of abacus training have shown that this training can induce specific changes in the brain. However, the neural mechanism underlying these changes remains elusive. Here, we reviewed the behavioral and imaging findings of comparisons between abacus experts and average control subjects and focused on changes in activation patterns and changes in brain structure. Finally, we noted the limitations and the future directions of this field. We concluded that although current studies have provided us with information about the mechanisms of abacus training, more research on abacus training is needed to understand its neural impact. PMID:26881089

  8. Neural Plasticity following Abacus Training in Humans: A Review and Future Directions

    PubMed Central

    Li, Yongxin; Chen, Feiyan; Huang, Wenhua

    2016-01-01

    The human brain has an enormous capacity to adapt to a broad variety of environmental demands. Previous studies in the field of abacus training have shown that this training can induce specific changes in the brain. However, the neural mechanism underlying these changes remains elusive. Here, we reviewed the behavioral and imaging findings of comparisons between abacus experts and average control subjects and focused on changes in activation patterns and changes in brain structure. Finally, we noted the limitations and the future directions of this field. We concluded that although current studies have provided us with information about the mechanisms of abacus training, more research on abacus training is needed to understand its neural impact. PMID:26881089

  9. Spatiotemporal discrimination in neural networks with short-term synaptic plasticity

    NASA Astrophysics Data System (ADS)

    Shlaer, Benjamin; Miller, Paul

    2015-03-01

    Cells in recurrently connected neural networks exhibit bistability, which allows for stimulus information to persist in a circuit even after stimulus offset, i.e. short-term memory. However, such a system does not have enough hysteresis to encode temporal information about the stimuli. The biophysically described phenomenon of synaptic depression decreases synaptic transmission strengths due to increased presynaptic activity. This short-term reduction in synaptic strengths can destabilize attractor states in excitatory recurrent neural networks, causing the network to move along stimulus dependent dynamical trajectories. Such a network can successfully separate amplitudes and durations of stimuli from the number of successive stimuli. Stimulus number, duration and intensity encoding in randomly connected attractor networks with synaptic depression. Front. Comput. Neurosci. 7:59., and so provides a strong candidate network for the encoding of spatiotemporal information. Here we explicitly demonstrate the capability of a recurrent neural network with short-term synaptic depression to discriminate between the temporal sequences in which spatial stimuli are presented.

  10. Bridging across cognitive training and brain plasticity: a neurally inspired computational model of interactive skill learning.

    PubMed

    Fu, Wai-Tat; Lee, Hyunkyu; Boot, Walter R; Kramer, Arthur F

    2013-03-01

    This article reviews recent empirical and brain imaging data on effects of cognitive training methods on complex interactive skill learning, and presents a neurally inspired computational model that characterizes the effects of these training methods. In particular, the article focuses on research that shows that variable priority training (VPT), which requires learners to shift their priorities to different task components during training, often leads to better acquisition and retention of skills than fixed priority training (FPT). However, there is only weak evidence that shows that VPT can enhance transfer of complex interactive skills to untrained situations. Brain imaging studies show that VPT leads to significantly lower activations and a higher reduction of activities in attentional control areas after training than FPT. Research also shows that the volume of the striatum predicts the learning effects, but only in VPT. The computational model, developed based on learning mechanisms at the neural level, bridges across the empirical and the braining imaging results by explaining the effects of VPT and FPT at both the behavioral and neural levels. The results were discussed in the context of previous findings on cognitive training. WIREs Cogn Sci 2013, 4:225-236. doi: 10.1002/wcs.1214 For further resources related to this article, please visit the WIREs website. PMID:26304197

  11. Neurosecretory Habituation in PC12 Cells: Modulation During Parallel Habituation

    NASA Astrophysics Data System (ADS)

    Martin, Paul T.; Koshland, Daniel E., Jr.

    1995-05-01

    PC12 cells habituate during repetitive stimulation with acetylcholine, bradykinin, or high potassium. Interspersing these stimulants did not affect the rate of habituation of the others, but it could modulate the amplitude of the norepinephrine secretion each could achieve. Stimulation with acetylcholine inhibited norepinephrine secretion caused by high potassium and bradykinin stimulation, while high potassium had no effect on acetylcholine or bradykinin, and bradykinin increased secretion caused by acetylcholine. Changes in norepinephrine secretion resulting from any of these stimulants correlated with changes in internal calcium levels. Cyclic AMP-, protein kinase C-, and calmodulin-dependent second messenger pathways all modulated norepinephrine secretion caused by acetylcholine and high potassium and showed a distinct hierarchy in their effectiveness. These data demonstrate that different receptor pathways can change the norepinephrine response of one another while not changing the levels of the molecules responsible for habituation.

  12. Social and Hormonal Triggers of Neural Plasticity in Naked Mole-Rats

    PubMed Central

    Holmes, Melissa M.; Seney, Marianne L.; Goldman, Bruce D.; Forger, Nancy G.

    2010-01-01

    Naked mole-rats are eusocial rodents that live in large social groups with a strict reproductive hierarchy. In each colony only a few individuals breed; all others are non-reproductive subordinates. We previously showed that breeders have increased volume of several brain regions linked to reproduction: the paraventricular nucleus of the hypothalamus (PVN), the principal nucleus of the bed nucleus of the stria terminalis (BSTp), and the medial amygdala (MeA). Breeders also have more large motoneurons in Onuf’s nucleus (ON) in the spinal cord, a cell group innervating perineal muscles that attach to the genitalia. Here, we sought to determine triggers for the neural changes seen in breeders. Specifically, we compared four groups of animals: subordinates, paired animals that did not reproduce, gonadally intact breeders, and gonadectomized breeders. We find that pairing alone is sufficient to cause breeder-like changes in volume of the PVN and cell size distribution in ON. In contrast, increases in BSTp volume were seen only in animals that actually reproduced. Those changes that were seen in successful breeders appear to be independent of gonadal steroids because long-term gonadectomy did not reverse the breeder-like neural changes in the PVN, BSTp or ON, although a trend for gonadectomized animals having larger MeA volumes was detected. Thus, neural changes associated with breeding status in naked mole-rats may be triggered by different aspects of the social and reproductive environment; once changes occur they are largely independent of gonadal hormones and may be permanent. PMID:21130812

  13. Habituation, sensitization, and Pavlovian conditioning

    PubMed Central

    Çevik, Münire Özlem

    2014-01-01

    In this brief review, I argue that the impact of a stimulus on behavioral control increase as the distance of the stimulus to the body decreases. Habituation, i.e., decrement in response intensity repetition of the triggering stimulus, is the default state for sensory processing, and the likelihood of habituation is higher for distal stimuli. Sensitization, i.e., increment in response intensity upon stimulus repetition, occurs in a state dependent manner for proximal stimuli that make direct contact with the body. In Pavlovian conditioning paradigms, the unconditioned stimulus (US) is always a more proximal stimulus than the conditioned stimulus (CS). The mechanisms of associative and non-associative learning are not independent. CS−US pairings lead to formation of associations if sensitizing modulation from a proximal US prevents the habituation for a distal anticipatory CS. PMID:24574983

  14. Habituation, sensitization, and Pavlovian conditioning.

    PubMed

    Cevik, Münire Özlem

    2014-01-01

    In this brief review, I argue that the impact of a stimulus on behavioral control increase as the distance of the stimulus to the body decreases. Habituation, i.e., decrement in response intensity repetition of the triggering stimulus, is the default state for sensory processing, and the likelihood of habituation is higher for distal stimuli. Sensitization, i.e., increment in response intensity upon stimulus repetition, occurs in a state dependent manner for proximal stimuli that make direct contact with the body. In Pavlovian conditioning paradigms, the unconditioned stimulus (US) is always a more proximal stimulus than the conditioned stimulus (CS). The mechanisms of associative and non-associative learning are not independent. CS-US pairings lead to formation of associations if sensitizing modulation from a proximal US prevents the habituation for a distal anticipatory CS. PMID:24574983

  15. Neural and Molecular Features on Charcot-Marie-Tooth Disease Plasticity and Therapy

    PubMed Central

    Juárez, Paula; Palau, Francesc

    2012-01-01

    In the peripheral nervous system disorders plasticity is related to changes on the axon and Schwann cell biology, and the synaptic formations and connections, which could be also a focus for therapeutic research. Charcot-Marie-Tooth disease (CMT) represents a large group of inherited peripheral neuropathies that involve mainly both motor and sensory nerves and induce muscular atrophy and weakness. Genetic analysis has identified several pathways and molecular mechanisms involving myelin structure and proper nerve myelination, transcriptional regulation, protein turnover, vesicle trafficking, axonal transport and mitochondrial dynamics. These pathogenic mechanisms affect the continuous signaling and dialogue between the Schwann cell and the axon, having as final result the loss of myelin and nerve maintenance; however, some late onset axonal CMT neuropathies are a consequence of Schwann cell specific changes not affecting myelin. Comprehension of molecular pathways involved in Schwann cell-axonal interactions is likely not only to increase the understanding of nerve biology but also to identify the molecular targets and cell pathways to design novel therapeutic approaches for inherited neuropathies but also for most common peripheral neuropathies. These approaches should improve the plasticity of the synaptic connections at the neuromuscular junction and regenerate cell viability based on improving myelin and axon interaction. PMID:22745917

  16. Cholecystokinin from the entorhinal cortex enables neural plasticity in the auditory cortex

    PubMed Central

    Li, Xiao; Yu, Kai; Zhang, Zicong; Sun, Wenjian; Yang, Zhou; Feng, Jingyu; Chen, Xi; Liu, Chun-Hua; Wang, Haitao; Guo, Yi Ping; He, Jufang

    2014-01-01

    Patients with damage to the medial temporal lobe show deficits in forming new declarative memories but can still recall older memories, suggesting that the medial temporal lobe is necessary for encoding memories in the neocortex. Here, we found that cortical projection neurons in the perirhinal and entorhinal cortices were mostly immunopositive for cholecystokinin (CCK). Local infusion of CCK in the auditory cortex of anesthetized rats induced plastic changes that enabled cortical neurons to potentiate their responses or to start responding to an auditory stimulus that was paired with a tone that robustly triggered action potentials. CCK infusion also enabled auditory neurons to start responding to a light stimulus that was paired with a noise burst. In vivo intracellular recordings in the auditory cortex showed that synaptic strength was potentiated after two pairings of presynaptic and postsynaptic activity in the presence of CCK. Infusion of a CCKB antagonist in the auditory cortex prevented the formation of a visuo-auditory association in awake rats. Finally, activation of the entorhinal cortex potentiated neuronal responses in the auditory cortex, which was suppressed by infusion of a CCKB antagonist. Together, these findings suggest that the medial temporal lobe influences neocortical plasticity via CCK-positive cortical projection neurons in the entorhinal cortex. PMID:24343575

  17. Behavioral and neural plasticity caused by early social experiences: the case of the honeybee

    PubMed Central

    Arenas, Andrés; Ramírez, Gabriela P.; Balbuena, María Sol; Farina, Walter M.

    2013-01-01

    Cognitive experiences during the early stages of life play an important role in shaping future behavior. Behavioral and neural long-term changes after early sensory and associative experiences have been recently reported in the honeybee. This invertebrate is an excellent model for assessing the role of precocious experiences on later behavior due to its extraordinarily tuned division of labor based on age polyethism. These studies are mainly focused on the role and importance of experiences occurred during the first days of the adult lifespan, their impact on foraging decisions, and their contribution to coordinate food gathering. Odor-rewarded experiences during the first days of honeybee adulthood alter the responsiveness to sucrose, making young hive bees more sensitive to assess gustatory features about the nectar brought back to the hive and affecting the dynamic of the food transfers and the propagation of food-related information within the colony. Early olfactory experiences lead to stable and long-term associative memories that can be successfully recalled after many days, even at foraging ages. Also they improve memorizing of new associative learning events later in life. The establishment of early memories promotes stable reorganization of the olfactory circuits inducing structural and functional changes in the antennal lobe (AL). Early rewarded experiences have relevant consequences at the social level too, biasing dance and trophallaxis partner choice and affecting recruitment. Here, we revised recent results in bees' physiology, behavior, and sociobiology to depict how the early experiences affect their cognition abilities and neural-related circuits. PMID:23986708

  18. Physiological, Molecular and Genetic Mechanisms of Long-Term Habituation

    SciTech Connect

    Calin-Jageman, Robert J

    2009-09-12

    Work funded on this grant has explored the mechanisms of long-term habituation, a ubiquitous form of learning that plays a key role in basic cognitive functioning. Specifically, behavioral, physiological, and molecular mechanisms of habituation have been explored using a simple model system, the tail-elicited siphon-withdrawal reflex (T-SWR) in the marine mollusk Aplysia californica. Substantial progress has been made on the first and third aims, providing some fundamental insights into the mechanisms by which memories are stored. We have characterized the physiological correlates of short- and long-term habituation. We found that short-term habituation is accompanied by a robust sensory adaptation, whereas long-term habituation is accompanied by alterations in sensory and interneuron synaptic efficacy. Thus, our data indicates memories can be shifted between different sites in a neural network as they are consolidated from short to long term. At the molecular level, we have accomplished microarray analysis comparing gene expression in both habituated and control ganglia. We have identified a network of putatively regulated transcripts that seems particularly targeted towards synaptic changes (e.g. SNAP25, calmodulin) . We are now beginning additional work to confirm regulation of these transcripts and build a more detailed understanding of the cascade of molecular events leading to the permanent storage of long-term memories. On the third aim, we have fostered a nascent neuroscience program via a variety of successful initiatives. We have funded over 11 undergraduate neuroscience scholars, several of whom have been recognized at national and regional levels for their research. We have also conducted a pioneering summer research program for community college students which is helping enhance access of underrepresented groups to life science careers. Despite minimal progress on the second aim, this project has provided a) novel insight into the network mechanisms by

  19. Effects of bursting dynamic features on the generation of multi-clustered structure of neural network with symmetric spike-timing-dependent plasticity learning rule.

    PubMed

    Liu, Hui; Song, Yongduan; Xue, Fangzheng; Li, Xiumin

    2015-11-01

    In this paper, the generation of multi-clustered structure of self-organized neural network with different neuronal firing patterns, i.e., bursting or spiking, has been investigated. The initially all-to-all-connected spiking neural network or bursting neural network can be self-organized into clustered structure through the symmetric spike-timing-dependent plasticity learning for both bursting and spiking neurons. However, the time consumption of this clustering procedure of the burst-based self-organized neural network (BSON) is much shorter than the spike-based self-organized neural network (SSON). Our results show that the BSON network has more obvious small-world properties, i.e., higher clustering coefficient and smaller shortest path length than the SSON network. Also, the results of larger structure entropy and activity entropy of the BSON network demonstrate that this network has higher topological complexity and dynamical diversity, which benefits for enhancing information transmission of neural circuits. Hence, we conclude that the burst firing can significantly enhance the efficiency of clustering procedure and the emergent clustered structure renders the whole network more synchronous and therefore more sensitive to weak input. This result is further confirmed from its improved performance on stochastic resonance. Therefore, we believe that the multi-clustered neural network which self-organized from the bursting dynamics has high efficiency in information processing. PMID:26627568

  20. Effects of bursting dynamic features on the generation of multi-clustered structure of neural network with symmetric spike-timing-dependent plasticity learning rule

    SciTech Connect

    Liu, Hui; Song, Yongduan; Xue, Fangzheng; Li, Xiumin

    2015-11-15

    In this paper, the generation of multi-clustered structure of self-organized neural network with different neuronal firing patterns, i.e., bursting or spiking, has been investigated. The initially all-to-all-connected spiking neural network or bursting neural network can be self-organized into clustered structure through the symmetric spike-timing-dependent plasticity learning for both bursting and spiking neurons. However, the time consumption of this clustering procedure of the burst-based self-organized neural network (BSON) is much shorter than the spike-based self-organized neural network (SSON). Our results show that the BSON network has more obvious small-world properties, i.e., higher clustering coefficient and smaller shortest path length than the SSON network. Also, the results of larger structure entropy and activity entropy of the BSON network demonstrate that this network has higher topological complexity and dynamical diversity, which benefits for enhancing information transmission of neural circuits. Hence, we conclude that the burst firing can significantly enhance the efficiency of clustering procedure and the emergent clustered structure renders the whole network more synchronous and therefore more sensitive to weak input. This result is further confirmed from its improved performance on stochastic resonance. Therefore, we believe that the multi-clustered neural network which self-organized from the bursting dynamics has high efficiency in information processing.

  1. Effects of bursting dynamic features on the generation of multi-clustered structure of neural network with symmetric spike-timing-dependent plasticity learning rule

    NASA Astrophysics Data System (ADS)

    Liu, Hui; Song, Yongduan; Xue, Fangzheng; Li, Xiumin

    2015-11-01

    In this paper, the generation of multi-clustered structure of self-organized neural network with different neuronal firing patterns, i.e., bursting or spiking, has been investigated. The initially all-to-all-connected spiking neural network or bursting neural network can be self-organized into clustered structure through the symmetric spike-timing-dependent plasticity learning for both bursting and spiking neurons. However, the time consumption of this clustering procedure of the burst-based self-organized neural network (BSON) is much shorter than the spike-based self-organized neural network (SSON). Our results show that the BSON network has more obvious small-world properties, i.e., higher clustering coefficient and smaller shortest path length than the SSON network. Also, the results of larger structure entropy and activity entropy of the BSON network demonstrate that this network has higher topological complexity and dynamical diversity, which benefits for enhancing information transmission of neural circuits. Hence, we conclude that the burst firing can significantly enhance the efficiency of clustering procedure and the emergent clustered structure renders the whole network more synchronous and therefore more sensitive to weak input. This result is further confirmed from its improved performance on stochastic resonance. Therefore, we believe that the multi-clustered neural network which self-organized from the bursting dynamics has high efficiency in information processing.

  2. In vivo reactive neural plasticity investigation by means of correlative two photon: electron microscopy

    NASA Astrophysics Data System (ADS)

    Allegra Mascaro, A. L.; Cesare, P.; Sacconi, L.; Grasselli, G.; Mandolesi, G.; Maco, B.; Knott, G.; Huang, L.; De Paola, V.; Strata, P.; Pavone, F. S.

    2013-02-01

    In the adult nervous system, different populations of neurons correspond to different regenerative behavior. Although previous works showed that olivocerebellar fibers are capable of axonal regeneration in a suitable environment as a response to injury1, we have hitherto no details about the real dynamics of fiber regeneration. We set up a model of singularly axotomized climbing fibers (CF) to investigate their reparative properties in the adult central nervous system (CNS) in vivo. Time lapse two-photon imaging has been combined to laser nanosurgery2, 3 to define a temporal pattern of the degenerative event and to follow the structural rearrangement after injury. To characterize the damage and to elucidate the possible formation of new synaptic contacts on the sprouted branches of the lesioned CF, we combined two-photon in vivo imaging with block face scanning electron microscopy (FIB-SEM). Here we describe the approach followed to characterize the reactive plasticity after injury.

  3. Speech Sound Processing Deficits and Training-Induced Neural Plasticity in Rats with Dyslexia Gene Knockdown

    PubMed Central

    Centanni, Tracy M.; Chen, Fuyi; Booker, Anne M.; Engineer, Crystal T.; Sloan, Andrew M.; Rennaker, Robert L.; LoTurco, Joseph J.; Kilgard, Michael P.

    2014-01-01

    In utero RNAi of the dyslexia-associated gene Kiaa0319 in rats (KIA-) degrades cortical responses to speech sounds and increases trial-by-trial variability in onset latency. We tested the hypothesis that KIA- rats would be impaired at speech sound discrimination. KIA- rats needed twice as much training in quiet conditions to perform at control levels and remained impaired at several speech tasks. Focused training using truncated speech sounds was able to normalize speech discrimination in quiet and background noise conditions. Training also normalized trial-by-trial neural variability and temporal phase locking. Cortical activity from speech trained KIA- rats was sufficient to accurately discriminate between similar consonant sounds. These results provide the first direct evidence that assumed reduced expression of the dyslexia-associated gene KIAA0319 can cause phoneme processing impairments similar to those seen in dyslexia and that intensive behavioral therapy can eliminate these impairments. PMID:24871331

  4. Phantom lower limb as a perceptual marker of neural plasticity in the mature human brain.

    PubMed

    Aglioti, S; Bonazzi, A; Cortese, F

    1994-03-22

    Three lower limb amputees, who reported phantom sensations, referred somatic stimuli delivered to skin regions proximal to the stump to select points on the phantom limb. Stimuli on the rectum and anus (e.g. during defecation) and on genital areas (e.g. during sexual intercourse) induced analogous, although less precise, mislocation to the phantom limb. Although the representation of the stump in the somatosensory pathway is lateral to that of the amputated lower limb, both anus and genitals are mapped medially to the areas formerly subserving the amputated lower limb. Therefore the mislocalization phenomenon can be considered as a perceptual landmark of new functional connections between the deprived areas and the adjacent ones, thus suggesting a dynamic neural remodelling in the mature nervous system, which was previously considered as a static entity. PMID:8022843

  5. Language-experience plasticity in neural representation of changes in pitch salience.

    PubMed

    Krishnan, Ananthanarayan; Gandour, Jackson T; Suresh, Chandan H

    2016-04-15

    Neural representation of pitch-relevant information at the brainstem and cortical levels of processing is influenced by language experience. A well-known attribute of pitch is its salience. Brainstem frequency following responses and cortical pitch specific responses, recorded concurrently, were elicited by a pitch salience continuum spanning weak to strong pitch of a dynamic, iterated rippled noise pitch contour-homolog of a Mandarin tone. Our aims were to assess how language experience (Chinese, English) affects i) enhancement of neural activity associated with pitch salience at brainstem and cortical levels, ii) the presence of asymmetry in cortical pitch representation, and iii) patterns of relative changes in magnitude along the pitch salience continuum. Peak latency (Fz: Na, Pb, and Nb) was shorter in the Chinese than the English group across the continuum. Peak-to-peak amplitude (Fz: Na-Pb, Pb-Nb) of the Chinese group grew larger with increasing pitch salience, but an experience-dependent advantage was limited to the Na-Pb component. At temporal sites (T7/T8), the larger amplitude of the Chinese group across the continuum was both limited to the Na-Pb component and the right temporal site. At the brainstem level, F0 magnitude gets larger as you increase pitch salience, and it too reveals Chinese superiority. A direct comparison of cortical and brainstem responses for the Chinese group reveals different patterns of relative changes in magnitude along the pitch salience continuum. Such differences may point to a transformation in pitch processing at the cortical level presumably mediated by local sensory and/or extrasensory influence overlaid on the brainstem output. PMID:26903418

  6. Activity-dependent plasticity in the isolated embryonic avian brainstem following manipulations of rhythmic spontaneous neural activity.

    PubMed

    Vincen-Brown, Michael A; Revill, Ann L; Pilarski, Jason Q

    2016-07-15

    When rhythmic spontaneous neural activity (rSNA) first appears in the embryonic chick brainstem and cranial nerve motor axons it is principally driven by nicotinic neurotransmission (NT). At this early age, the nicotinic acetylcholine receptor (nAChR) agonist nicotine is known to critically disrupt rSNA at low concentrations (0.1-0.5μM), which are levels that mimic the blood plasma levels of a fetus following maternal cigarette smoking. Thus, we quantified the effect of persistent exposure to exogenous nicotine on rSNA using an in vitro developmental model. We found that rSNA was eliminated by continuous bath application of exogenous nicotine, but rSNA recovered activity within 6-12h despite the persistent activation and desensitization of nAChRs. During the recovery period rSNA was critically driven by chloride-mediated membrane depolarization instead of nicotinic NT. To test whether this observed compensation was unique to the antagonism of nicotinic NT or whether the loss of spiking behavior also played a role, we eliminated rSNA by lowering overall excitatory drive with a low [K(+)]o superfusate. In this context, rSNA again recovered, although the recovery time was much quicker, and exhibited a lower frequency, higher duration, and an increase in the number of bursts per episode when compared to control embryos. Importantly, we show that the main compensatory response to lower overall excitatory drive, similar to nicotinergic block, is a result of potentiated chloride mediated membrane depolarization. These results support increasing evidence that early neural circuits sense spiking behavior to maintain primordial bioelectric rhythms. Understanding the nature of developmental plasticity in the nervous system, especially versions that preserve rhythmic behaviors following clinically meaningful environmental stimuli, both normal and pathological, will require similar studies to determine the consequences of feedback compensation at more mature chronological ages

  7. Generalized Habituation of Concept Stimuli in Toddlers

    ERIC Educational Resources Information Center

    Faulkender, Patricia J.; And Others

    1974-01-01

    An evaluation of selective generalization of habituation on the basis of meaningful categories of stimuli. Also explored are the sex differences in conceptual generalization of habituation. Subjects were 36 toddlers with a mean age of 40 months. (SDH)

  8. Criminal Careers of Habitual Felons.

    ERIC Educational Resources Information Center

    Petersilia, Joan; And Others

    The criminal development of habitual felons was examined by means of lengthy interviews with 49 prison inmates, all armed robbers serving at least their second prison terms. Results are not considered generalized, but should be regarded as 49 case studies. Although some of the findings were consistent with traditional images (juvenile offender…

  9. A Spiking Neural Network Model of the Medial Superior Olive Using Spike Timing Dependent Plasticity for Sound Localization

    PubMed Central

    Glackin, Brendan; Wall, Julie A.; McGinnity, Thomas M.; Maguire, Liam P.; McDaid, Liam J.

    2010-01-01

    Sound localization can be defined as the ability to identify the position of an input sound source and is considered a powerful aspect of mammalian perception. For low frequency sounds, i.e., in the range 270 Hz–1.5 KHz, the mammalian auditory pathway achieves this by extracting the Interaural Time Difference between sound signals being received by the left and right ear. This processing is performed in a region of the brain known as the Medial Superior Olive (MSO). This paper presents a Spiking Neural Network (SNN) based model of the MSO. The network model is trained using the Spike Timing Dependent Plasticity learning rule using experimentally observed Head Related Transfer Function data in an adult domestic cat. The results presented demonstrate how the proposed SNN model is able to perform sound localization with an accuracy of 91.82% when an error tolerance of ±10° is used. For angular resolutions down to 2.5°, it will be demonstrated how software based simulations of the model incur significant computation times. The paper thus also addresses preliminary implementation on a Field Programmable Gate Array based hardware platform to accelerate system performance. PMID:20802855

  10. Acoustic Emission Source Location in Unidirectional Carbon-Fibre-Reinforced Plastic Plates Using Virtually Trained Artificial Neural Networks

    SciTech Connect

    Caprino, G.; Lopresto, V.; Leone, C.; Papa, I.

    2010-06-02

    Acoustic emission source location in a unidirectional carbon-fibre-reinforced plastic plate was attempted employing Artificial Neural Network (ANN) technology. The acoustic emission events were produced by a lead break, and the response wave received by piezoelectric sensors, type VS150-M resonant at 150 kHz. The waves were detected by a Vallen AMSY4 eight-channel instrumentation. The time of arrival, determined through the conventional threshold crossing technique, was used to measure the dependence of wave velocity on fibre orientation. A simple empirical formula, relying on classical lamination and suggested by wave propagation theory, was able to accurately model the experimental trend. Based on the formula, virtual training and testing data sets were generated for the case of a plate monitored by three transducers, and adopted to select two potentially effective ANN architectures. For final validation, experimental tests were carried out, positioning the source at predetermined points evenly distributed within the plate area. A very satisfactory correlation was found between the actual source locations and the ANN predictions.

  11. Prediction of Damage Factor in end Milling of Glass Fibre Reinforced Plastic Composites Using Artificial Neural Network

    NASA Astrophysics Data System (ADS)

    Erkan, Ömer; Işık, Birhan; Çiçek, Adem; Kara, Fuat

    2013-08-01

    Glass fibre reinforced plastic (GFRP) composites are an economic alternative to engineering materials because of their superior properties. Some damages on the surface occur due to their complex cutting mechanics in cutting process. Minimisation of the damages is fairly important in terms of product quality. In this study, a GFRP composite material was milled to experimentally minimise the damages on the machined surfaces, using two, three and four flute end mills at different combinations of cutting parameters. Experimental results showed that the damage factor increased with increasing cutting speed and feed rate, on the other hand, it was found that the damage factor decreased with increasing depth of cut and number of the flutes. In addition, analysis of variance (ANOVA) results clearly revealed that the feed rate was the most influential parameter affecting the damage factor in end milling of GFRP composites. Also, in present study, Artificial Neural Network (ANN) models with five learning algorithms were used in predicting the damage factor to reduce number of expensive and time-consuming experiments. The highest performance was obtained by 4-10-1 network structure with LM learning algorithm. ANN was notably successful in predicting the damage factor due to higher R2 and lower RMSE and MEP.

  12. Neural Plasticity and Memory: Is Memory Encoded in Hydrogen Bonding Patterns?

    PubMed

    Amtul, Zareen; Rahman, Atta-Ur

    2016-02-01

    Current models of memory storage recognize posttranslational modification vital for short-term and mRNA translation for long-lasting information storage. However, at the molecular level things are quite vague. A comprehensive review of the molecular basis of short and long-lasting synaptic plasticity literature leads us to propose that the hydrogen bonding pattern at the molecular level may be a permissive, vital step of memory storage. Therefore, we propose that the pattern of hydrogen bonding network of biomolecules (glycoproteins and/or DNA template, for instance) at the synapse is the critical edifying mechanism essential for short- and long-term memories. A novel aspect of this model is that nonrandom impulsive (or unplanned) synaptic activity functions as a synchronized positive-feedback rehearsal mechanism by revising the configurations of the hydrogen bonding network by tweaking the earlier tailored hydrogen bonds. This process may also maintain the elasticity of the related synapses involved in memory storage, a characteristic needed for such networks to alter intricacy and revise endlessly. The primary purpose of this review is to stimulate the efforts to elaborate the mechanism of neuronal connectivity both at molecular and chemical levels. PMID:25168338

  13. In vivo imaging of neural reactive plasticity after laser axotomy in cerebellar cortex

    NASA Astrophysics Data System (ADS)

    Allegra Mascaro, A. L.; Sacconi, L.; Maco, B.; Knott, G. W.; Pavone, F. S.

    2014-03-01

    Multi-photon imaging provides valuable insights into the continuous reshaping of neuronal connectivity in live brain. We previously showed that single neuron or even single spine ablation can be achieved by laser-mediated dissection. Furthermore, single axonal branches can be dissected avoiding collateral damage to the adjacent dendrite and the formation of a persistent glial scar. Here, we describe the procedure to address the structural plasticity of cerebellar climbing fibers by combining two-photon in vivo imaging with laser axotomy in a mouse model. This method is a powerful tool to study the basic mechanisms of axonal rewiring after single branch axotomy in vivo. In fact, despite the denervated area being very small, the injured axons consistently reshape the connectivity with surrounding neurons, as indicated by the increase in the turnover of synaptic boutons. In addition, time-lapse imaging reveals the sprouting of new branches from the injured axon. Newly formed branches with varicosities suggest the possible formation of synaptic contacts. Correlative light and electron microscopy revealed that the sprouted branch contains large numbers of vesicles, with varicosities in the close vicinity of Purkinje dendrites.

  14. Cortical stimulation consolidates and reactivates visual experience: neural plasticity from magnetic entrainment of visual activity.

    PubMed

    Liao, Hsin-I; Wu, Daw-An; Halelamien, Neil; Shimojo, Shinsuke

    2013-01-01

    Delivering transcranial magnetic stimulation (TMS) shortly after the end of a visual stimulus can cause a TMS-induced 'replay' or 'visual echo' of the visual percept. In the current study, we find an entrainment effect that after repeated elicitations of TMS-induced replay with the same visual stimulus, the replay can be induced by TMS alone, without the need for the physical visual stimulus. In Experiment 1, we used a subjective rating task to examine the phenomenal aspects of TMS-entrained replays. In Experiment 2, we used an objective masking paradigm to quantitatively validate the phenomenon and to examine the involvement of low-level mechanisms. Results showed that the TMS-entrained replay was not only phenomenally experienced (Exp.1), but also able to hamper letter identification (Exp.2). The findings have implications in several directions: (1) the visual cortical representation and iconic memory, (2) experience-based plasticity in the visual cortex, and (3) their relationship to visual awareness. PMID:23863977

  15. Excessive Sensory Stimulation during Development Alters Neural Plasticity and Vulnerability to Cocaine in Mice.

    PubMed

    Ravinder, Shilpa; Donckels, Elizabeth A; Ramirez, Julian S B; Christakis, Dimitri A; Ramirez, Jan-Marino; Ferguson, Susan M

    2016-01-01

    Early life experiences affect the formation of neuronal networks, which can have a profound impact on brain function and behavior later in life. Previous work has shown that mice exposed to excessive sensory stimulation during development are hyperactive and novelty seeking, and display impaired cognition compared with controls. In this study, we addressed the issue of whether excessive sensory stimulation during development could alter behaviors related to addiction and underlying circuitry in CD-1 mice. We found that the reinforcing properties of cocaine were significantly enhanced in mice exposed to excessive sensory stimulation. Moreover, although these mice displayed hyperactivity that became more pronounced over time, they showed impaired persistence of cocaine-induced locomotor sensitization. These behavioral effects were associated with alterations in glutamatergic transmission in the nucleus accumbens and amygdala. Together, these findings suggest that excessive sensory stimulation in early life significantly alters drug reward and the neural circuits that regulate addiction and attention deficit hyperactivity. These observations highlight the consequences of early life experiences and may have important implications for children growing up in today's complex technological environment. PMID:27588306

  16. Excessive Sensory Stimulation during Development Alters Neural Plasticity and Vulnerability to Cocaine in Mice

    PubMed Central

    Ravinder, Shilpa; Christakis, Dimitri A.

    2016-01-01

    Abstract Early life experiences affect the formation of neuronal networks, which can have a profound impact on brain function and behavior later in life. Previous work has shown that mice exposed to excessive sensory stimulation during development are hyperactive and novelty seeking, and display impaired cognition compared with controls. In this study, we addressed the issue of whether excessive sensory stimulation during development could alter behaviors related to addiction and underlying circuitry in CD-1 mice. We found that the reinforcing properties of cocaine were significantly enhanced in mice exposed to excessive sensory stimulation. Moreover, although these mice displayed hyperactivity that became more pronounced over time, they showed impaired persistence of cocaine-induced locomotor sensitization. These behavioral effects were associated with alterations in glutamatergic transmission in the nucleus accumbens and amygdala. Together, these findings suggest that excessive sensory stimulation in early life significantly alters drug reward and the neural circuits that regulate addiction and attention deficit hyperactivity. These observations highlight the consequences of early life experiences and may have important implications for children growing up in today’s complex technological environment. PMID:27588306

  17. Odor Experiences during Preimaginal Stages Cause Behavioral and Neural Plasticity in Adult Honeybees.

    PubMed

    Ramírez, Gabriela; Fagundez, Carol; Grosso, Juan P; Argibay, Pablo; Arenas, Andrés; Farina, Walter M

    2016-01-01

    In eusocial insects, experiences acquired during the development have long-term consequences on mature behavior. In the honeybee that suffers profound changes associated with metamorphosis, the effect of odor experiences at larval instars on the subsequent physiological and behavioral response is still unclear. To address the impact of preimaginal experiences on the adult honeybee, colonies containing larvae were fed scented food. The effect of the preimaginal experiences with the food odor was assessed in learning performance, memory retention and generalization in 3-5- and 17-19 day-old bees, in the regulation of their expression of synaptic-related genes and in the perception and morphology of their antennae. Three-five day old bees that experienced 1-hexanol (1-HEX) as food scent responded more to the presentation of the odor during the 1-HEX conditioning than control bees (i.e., bees reared in colonies fed unscented food). Higher levels of proboscis extension response (PER) to 1-HEX in this group also extended to HEXA, the most perceptually similar odor to the experienced one that we tested. These results were not observed for the group tested at older ages. In the brain of young adults, larval experiences triggered similar levels of neurexins (NRXs) and neuroligins (Nlgs) expression, two proteins that have been involved in synaptic formation after associative learning. At the sensory periphery, the experience did not alter the number of the olfactory sensilla placoidea, but did reduce the electrical response of the antennae to the experienced and novel odor. Our study provides a new insight into the effects of preimaginal experiences in the honeybee and the mechanisms underlying olfactory plasticity at larval stage of holometabolous insects. PMID:27375445

  18. Odor Experiences during Preimaginal Stages Cause Behavioral and Neural Plasticity in Adult Honeybees

    PubMed Central

    Ramírez, Gabriela; Fagundez, Carol; Grosso, Juan P.; Argibay, Pablo; Arenas, Andrés; Farina, Walter M.

    2016-01-01

    In eusocial insects, experiences acquired during the development have long-term consequences on mature behavior. In the honeybee that suffers profound changes associated with metamorphosis, the effect of odor experiences at larval instars on the subsequent physiological and behavioral response is still unclear. To address the impact of preimaginal experiences on the adult honeybee, colonies containing larvae were fed scented food. The effect of the preimaginal experiences with the food odor was assessed in learning performance, memory retention and generalization in 3–5- and 17–19 day-old bees, in the regulation of their expression of synaptic-related genes and in the perception and morphology of their antennae. Three-five day old bees that experienced 1-hexanol (1-HEX) as food scent responded more to the presentation of the odor during the 1-HEX conditioning than control bees (i.e., bees reared in colonies fed unscented food). Higher levels of proboscis extension response (PER) to 1-HEX in this group also extended to HEXA, the most perceptually similar odor to the experienced one that we tested. These results were not observed for the group tested at older ages. In the brain of young adults, larval experiences triggered similar levels of neurexins (NRXs) and neuroligins (Nlgs) expression, two proteins that have been involved in synaptic formation after associative learning. At the sensory periphery, the experience did not alter the number of the olfactory sensilla placoidea, but did reduce the electrical response of the antennae to the experienced and novel odor. Our study provides a new insight into the effects of preimaginal experiences in the honeybee and the mechanisms underlying olfactory plasticity at larval stage of holometabolous insects. PMID:27375445

  19. MicroRNA dysregulation following spinal cord contusion: implications for neural plasticity and repair

    PubMed Central

    Strickland, Eric R.; Hook, Michelle A.; Balaraman, Sridevi; Huie, J. Russell; Grau, James W.; Miranda, Rajesh C.

    2011-01-01

    Spinal cord injury (SCI) is medically and socioeconomically debilitating. Currently, there is a paucity of effective therapies that promote regeneration at the injury site, and limited understanding of mechanisms that can be utilized to therapeutically manipulate spinal cord plasticity. MicroRNAs (miRNAs) constitute novel targets for therapeutic intervention to promote repair and regeneration. Microarray comparisons of the injury sites of contused and sham rat spinal cords, harvested 4 and 14 days following SCI, showed that 32 miRNAs, including miR124, miR129, and miR1, were significantly down-regulated, whereas SNORD2, a translation-initiation factor, was induced. Additionally, 3 miRNAs including miR21 were significantly induced, indicating adaptive induction of an anti-apoptotic response in the injured cord. Validation of miRNA expression by qRT-PCR and in situ hybridization assays revealed that the influence of SCI on miRNA expression persists up to 14 days and expands both anteriorly and caudally beyond the lesion site. Specifically, changes in miR129-2 and miR146a expression significantly explained the variability in initial injury severity, suggesting that these specific miRNAs may serve as biomarkers and therapeutic targets for SCI. Moreover, the pattern of miRNA changes coincided spatially and temporally with the appearance of SOX2, nestin, and REST immunoreactivity, suggesting that aberrant expression of these miRNAs may not only reflect the emergence of stem cell niches, but also the reemergence in surviving neurons of a pre-neuronal phenotype. Finally, bioinformatics analysis of validated miRNA-targeted genes indicates that miRNA dysregulation may explain apoptosis susceptibility and aberrant cell cycle associated with a loss of neuronal identity, which underlies the pathogenesis of secondary SCI. PMID:21513774

  20. Brain lateralization and neural plasticity for musical and cognitive abilities in an epileptic musician.

    PubMed

    Trujillo-Pozo, Isabel; Martín-Monzón, Isabel; Rodríguez-Romero, Rafael

    2013-01-01

    The use of intracarotid propofol procedure (IPP) when assessing musical lateralization has not been reported in literature up to now. This procedure (similar to Wada Test) has provided the opportunity to investigate not only lateralization of language and memory functions on epileptic patients but also offers a functional mapping approach with superior spatial and temporal resolution to analyze the lateralization of musical abilities. Findings in literature suggest that musical training modifies functional and structural brain organization. We studied hemispheric lateralization in a professional musician, a 33 years old woman with refractory left medial temporal lobe (MTL) epilepsy (TLE). A longitudinal neuropsychological study was performed over a period of 21 months. Before epilepsy surgery, musical abilities, language and memory were tested during IPP by means of a novel and exhaustive neuropsychological battery focusing on the processing of music. We used a selection of stimuli to analyze listening, score reading, and tempo discrimination. Our results suggested that IPP is an excellent method to determine not only language, semantic, and episodic memory, but also musical dominance in a professional musician who may be candidate for epilepsy surgery. Neuropsychological testing revealed that right hemisphere's patient is involved in semantic and episodic musical memory processes, whereas her score reading and tempo processing require contribution from both hemispheres. At one-year follow-up, outcome was excellent with respect to seizures and professional skills, meanwhile cognitive abilities improved. These findings indicate that IPP helps to predict who might be at risk for postoperative musical, language, and memory deficits after epilepsy surgery. Our research suggests that musical expertise and epilepsy critically modifies long-term memory processes and induces brain structural and functional plasticity. PMID:24367312

  1. MicroRNA dysregulation following spinal cord contusion: implications for neural plasticity and repair.

    PubMed

    Strickland, E R; Hook, M A; Balaraman, S; Huie, J R; Grau, J W; Miranda, R C

    2011-07-14

    Spinal cord injury (SCI) is medically and socioeconomically debilitating. Currently, there is a paucity of effective therapies that promote regeneration at the injury site, and limited understanding of mechanisms that can be utilized to therapeutically manipulate spinal cord plasticity. MicroRNAs (miRNAs) constitute novel targets for therapeutic intervention to promote repair and regeneration. Microarray comparisons of the injury sites of contused and sham rat spinal cords, harvested 4 and 14 days following SCI, showed that 32 miRNAs, including miR124, miR129, and miR1, were significantly down-regulated, whereas SNORD2, a translation-initiation factor, was induced. Additionally, three miRNAs including miR21 were significantly induced, indicating adaptive induction of an anti-apoptotic response in the injured cord. Validation of miRNA expression by qRT-PCR and in situ hybridization assays revealed that the influence of SCI on miRNA expression persists up to 14 days and expands both anteriorly and caudally beyond the lesion site. Specifically, changes in miR129-2 and miR146a expression significantly explained the variability in initial injury severity, suggesting that these specific miRNAs may serve as biomarkers and therapeutic targets for SCI. Moreover, the pattern of miRNA changes coincided spatially and temporally with the appearance of SOX2, nestin, and REST immunoreactivity, suggesting that aberrant expression of these miRNAs may not only reflect the emergence of stem cell niches, but also the reemergence in surviving neurons of a pre-neuronal phenotype. Finally, bioinformatics analysis of validated miRNA-targeted genes indicates that miRNA dysregulation may explain apoptosis susceptibility and aberrant cell cycle associated with a loss of neuronal identity, which underlies the pathogenesis of secondary SCI. PMID:21513774

  2. Brain lateralization and neural plasticity for musical and cognitive abilities in an epileptic musician

    PubMed Central

    Trujillo-Pozo, Isabel; Martín-Monzón, Isabel; Rodríguez-Romero, Rafael

    2013-01-01

    The use of intracarotid propofol procedure (IPP) when assessing musical lateralization has not been reported in literature up to now. This procedure (similar to Wada Test) has provided the opportunity to investigate not only lateralization of language and memory functions on epileptic patients but also offers a functional mapping approach with superior spatial and temporal resolution to analyze the lateralization of musical abilities. Findings in literature suggest that musical training modifies functional and structural brain organization. We studied hemispheric lateralization in a professional musician, a 33 years old woman with refractory left medial temporal lobe (MTL) epilepsy (TLE). A longitudinal neuropsychological study was performed over a period of 21 months. Before epilepsy surgery, musical abilities, language and memory were tested during IPP by means of a novel and exhaustive neuropsychological battery focusing on the processing of music. We used a selection of stimuli to analyze listening, score reading, and tempo discrimination. Our results suggested that IPP is an excellent method to determine not only language, semantic, and episodic memory, but also musical dominance in a professional musician who may be candidate for epilepsy surgery. Neuropsychological testing revealed that right hemisphere's patient is involved in semantic and episodic musical memory processes, whereas her score reading and tempo processing require contribution from both hemispheres. At one-year follow-up, outcome was excellent with respect to seizures and professional skills, meanwhile cognitive abilities improved. These findings indicate that IPP helps to predict who might be at risk for postoperative musical, language, and memory deficits after epilepsy surgery. Our research suggests that musical expertise and epilepsy critically modifies long-term memory processes and induces brain structural and functional plasticity. PMID:24367312

  3. The superiority in voice processing of the blind arises from neural plasticity at sensory processing stages.

    PubMed

    Föcker, Julia; Best, Anna; Hölig, Cordula; Röder, Brigitte

    2012-07-01

    Blind people rely much more on voices compared to sighted individuals when identifying other people. Previous research has suggested a faster processing of auditory input in blind individuals than sighted controls and an enhanced activation of temporal cortical regions during voice processing. The present study used event-related potentials (ERPs) to single out the sub-processes of auditory person identification that change and allow for superior voice processing after congenital blindness. A priming paradigm was employed in which two successive voices (S1 and S2) of either the same (50% of the trials) or different actors were presented. Congenitally blind and matched sighted participants made an old-young decision on the S2. During the pre-experimental familiarization with the stimuli, congenitally blind individuals showed faster learning rates than sighted controls. Reaction times were shorter in person-congruent trials than in person-incongruent trials in both groups. ERPs to S2 stimuli in person-incongruent as compared to person-congruent trials were significantly enhanced at early processing stages (100-160 ms) in congenitally blind participants only. A later negative ERP effect (>200 ms) was found in both groups. The scalp topographies of the experimental effects were characterized by a central and parietal distribution in the sighted but a more posterior distribution in the congenitally blind. These results provide evidence for an improvement of early voice processing stages and a reorganization of the person identification system as a neural correlate of compensatory behavioral improvements following congenital blindness. PMID:22588063

  4. Distinct Neural Mechanisms Mediate Olfactory Memory Formation at Different Timescales

    ERIC Educational Resources Information Center

    McNamara, Ann Marie; Magidson, Phillip D.; Linster, Christiane; Wilson, Donald A.; Cleland, Thomas A.

    2008-01-01

    Habituation is one of the oldest forms of learning, broadly expressed across sensory systems and taxa. Here, we demonstrate that olfactory habituation induced at different timescales (comprising different odor exposure and intertrial interval durations) is mediated by different neural mechanisms. First, the persistence of habituation memory is…

  5. Performance enhancement at the cost of potential brain plasticity: neural ramifications of nootropic drugs in the healthy developing brain

    PubMed Central

    Urban, Kimberly R.; Gao, Wen-Jun

    2014-01-01

    Cognitive enhancement is perhaps one of the most intriguing and controversial topics in neuroscience today. Currently, the main classes of drugs used as potential cognitive enhancers include psychostimulants (methylphenidate (MPH), amphetamine), but wakefulness-promoting agents (modafinil) and glutamate activators (ampakine) are also frequently used. Pharmacologically, substances that enhance the components of the memory/learning circuits—dopamine, glutamate (neuronal excitation), and/or norepinephrine—stand to improve brain function in healthy individuals beyond their baseline functioning. In particular, non-medical use of prescription stimulants such as MPH and illicit use of psychostimulants for cognitive enhancement have seen a recent rise among teens and young adults in schools and college campuses. However, this enhancement likely comes with a neuronal, as well as ethical, cost. Altering glutamate function via the use of psychostimulants may impair behavioral flexibility, leading to the development and/or potentiation of addictive behaviors. Furthermore, dopamine and norepinephrine do not display linear effects; instead, their modulation of cognitive and neuronal function maps on an inverted-U curve. Healthy individuals run the risk of pushing themselves beyond optimal levels into hyperdopaminergic and hypernoradrenergic states, thus vitiating the very behaviors they are striving to improve. Finally, recent studies have begun to highlight potential damaging effects of stimulant exposure in healthy juveniles. This review explains how the main classes of cognitive enhancing drugs affect the learning and memory circuits, and highlights the potential risks and concerns in healthy individuals, particularly juveniles and adolescents. We emphasize the performance enhancement at the potential cost of brain plasticity that is associated with the neural ramifications of nootropic drugs in the healthy developing brain. PMID:24860437

  6. Habituation and 1/f-noise

    NASA Astrophysics Data System (ADS)

    West, B. J.; Grigolini, P.

    2010-12-01

    Habituation is the reversible decrement in the behavior response to a novel and repeating stimulus without a corresponding change in the strength of the stimulus. Dishabituation is a complementary phenomenon in which a habituated process is revitalized by presenting a complex stimulus that is distinct from the original. Herein we propose a statistical habituation model (SHM); a phenomenological model based on a generalization of linear response theory and discrete events. The SHM suggests that the fundamental mechanism producing habituation in its myriad of forms, as well as the associated dishabituation, is the 1/f-noise that is generically produced in complex neuronal networks.

  7. Differential Role of Inhibition in Habituation of Two Independent Afferent Pathways to a Common Motor Output

    ERIC Educational Resources Information Center

    Bristol, Adam S.; Carew, Thomas J.

    2005-01-01

    Many studies of the neural mechanisms of learning have focused on habituation, a simple form of learning in which a response decrements with repeated stimulation. In the siphon-elicited siphon withdrawal reflex (S-SWR) of the marine mollusk "Aplysia," the prevailing view is that homosynaptic depression of primary sensory afferents underlies…

  8. Impaired Visual Habituation in Adults with ADHD

    ERIC Educational Resources Information Center

    Massa, Jacqueline; O'Desky, Ilyse H.

    2012-01-01

    Objective: Habituation has an important role in attention. By reducing one's sensitivity to a constant source of stimulation, it frees up attention resources to process new distinct items. Impaired habituation may disrupt sustained attention via inability to modulate the repeated intrusion of irrelevant stimuli. Method: Using Troxler fading, this…

  9. Habituation of vestibular responses: An overview

    NASA Technical Reports Server (NTRS)

    Collins, W. E.

    1973-01-01

    An historical survey of vestibular habituation experiments has been undertaken. Methodological problems are presented briefly, and the influence of arousal on vestibular responses is detailed. Data obtained from animals and from man are treated separately. At least for man, the term habituation may be better defined by a dynamic change in the form of vestibular responses than by a simple response reduction.

  10. Cultivating Sentimental Dispositions through Aristotelian Habituation

    ERIC Educational Resources Information Center

    Steutel, Jan; Spiecker, Ben

    2004-01-01

    The beliefs both that sentimental education is a vital part of moral education and that habituation is a vital part of sentimental education can be counted as being at the hard core of the Aristotelian tradition of moral thought and action. On the basis of an explanation of the defining characteristics of Aristotelian habituation, this paper…

  11. Habitual routines in task-performing groups

    NASA Technical Reports Server (NTRS)

    Gersick, C. J.; Hackman, J. R.

    1990-01-01

    Groups, like individuals, often develop habitual routines for dealing with frequently encountered stimuli. Although such routines are consequential for group life and work, little is known about them. This paper reconnoiters the territory of habitual behavior in groups that perform work within organizations. We offer a definition of group habits, identify their functions and dysfunctions, suggest how they develop and are maintained, and identify the circumstances when they are likely to be altered or abandoned. Throughout, we give special attention to the social nature of habitual routines in groups, to the interaction between habitual behavior and group life cycle phenomena, and to the role of the organizational context in prompting, shaping, and terminating habitual routines.

  12. Neural stem cells and neuro/gliogenesis in the central nervous system: understanding the structural and functional plasticity of the developing, mature, and diseased brain.

    PubMed

    Yamaguchi, Masahiro; Seki, Tatsunori; Imayoshi, Itaru; Tamamaki, Nobuaki; Hayashi, Yoshitaka; Tatebayashi, Yoshitaka; Hitoshi, Seiji

    2016-05-01

    Neurons and glia in the central nervous system (CNS) originate from neural stem cells (NSCs). Knowledge of the mechanisms of neuro/gliogenesis from NSCs is fundamental to our understanding of how complex brain architecture and function develop. NSCs are present not only in the developing brain but also in the mature brain in adults. Adult neurogenesis likely provides remarkable plasticity to the mature brain. In addition, recent progress in basic research in mental disorders suggests an etiological link with impaired neuro/gliogenesis in particular brain regions. Here, we review the recent progress and discuss future directions in stem cell and neuro/gliogenesis biology by introducing several topics presented at a joint meeting of the Japanese Association of Anatomists and the Physiological Society of Japan in 2015. Collectively, these topics indicated that neuro/gliogenesis from NSCs is a common event occurring in many brain regions at various ages in animals. Given that significant structural and functional changes in cells and neural networks are accompanied by neuro/gliogenesis from NSCs and the integration of newly generated cells into the network, stem cell and neuro/gliogenesis biology provides a good platform from which to develop an integrated understanding of the structural and functional plasticity that underlies the development of the CNS, its remodeling in adulthood, and the recovery from diseases that affect it. PMID:26578509

  13. Multimodal Plasticity in Dorsal Striatum While Learning a Lateralized Navigation Task.

    PubMed

    Hawes, Sarah L; Evans, Rebekah C; Unruh, Benjamin A; Benkert, Elizabeth E; Gillani, Fawad; Dumas, Theodore C; Blackwell, Kim T

    2015-07-22

    Growing evidence supports a critical role for the dorsal striatum in cognitive as well as motor control. Both lesions and in vivo recordings demonstrate a transition in the engaged dorsal striatal subregion, from dorsomedial to dorsolateral, as skill performance shifts from an attentive phase to a more automatic or habitual phase. What are the neural mechanisms supporting the cognitive and behavioral transitions in skill learning? To pursue this question, we used T-maze training during which rats transition from early, attentive (dorsomedial) to late habitual (dorsolateral) performance. Following early or late training, we performed the first direct comparison of bidirectional synaptic plasticity in striatal brain slices, and the first evaluation of striatal synaptic plasticity by hemisphere relative to a learned turn. Consequently, we find that long-term potentiation and long-term depression are independently modulated with learning rather than reciprocally linked as previously suggested. Our results establish that modulation of evoked synaptic plasticity with learning depends on striatal subregion, training stage, and hemisphere relative to the learned turn direction. Exclusive to the contralateral hemisphere, intrinsic excitability is enhanced in dorsomedial relative to dorsolateral medium spiny neurons early in training and population responses are dampened late in training. Neuronal reconstructions indicate dendritic remodeling after training, which may represent a novel form of pruning. In conclusion, we describe region- and hemisphere-specific changes in striatal synaptic, intrinsic, and morphological plasticity which correspond to T-maze learning stages, and which may play a role in the cognitive transition between attentive and habitual strategies. Significance statement: We investigated neural plasticity in dorsal striatum from rats that were briefly or extensively trained on a directional T-maze task. Our results demonstrate that both the extent of

  14. A fronto-striato-subthalamic-pallidal network for goal-directed and habitual inhibition.

    PubMed

    Jahanshahi, Marjan; Obeso, Ignacio; Rothwell, John C; Obeso, José A

    2015-12-01

    Classically, the basal ganglia have been considered to have a role in producing habitual and goal-directed behaviours. In this article, we review recent evidence that expands this role, indicating that the basal ganglia are also involved in neural and behavioural inhibition in the motor and non-motor domains. We then distinguish between goal-directed and habitual (also known as automatic) inhibition mediated by fronto-striato-subthalamic-pallido-thalamo-cortical networks. We also suggest that imbalance between goal-directed and habitual action and inhibition contributes to some manifestations of Parkinson's disease, Tourette syndrome and obsessive-compulsive disorder. Finally, we propose that basal ganglia surgery improves these disorders by restoring a functional balance between facilitation and inhibition. PMID:26530468

  15. Stress habituation, body shape and cardiovascular mortality.

    PubMed

    Peters, Achim; McEwen, Bruce S

    2015-09-01

    High cardiovascular mortality is well documented in lean phenotypes exhibiting visceral fat accumulation. In contrast, corpulent phenotypes with predominantly subcutaneous fat accumulation display a surprisingly low mortality. The term 'obesity paradox' reflects the difficulty in understanding the biological mechanisms underlying these clinical observations. The allostatic load model of chronic stress focuses on glucocorticoid dysregulation as part of a 'network of allostasis' involving autonomic, endocrine, metabolic, and immune mediators. Here, we expand upon the energetic demands of the brain and show that 'habituators' and 'non-habituators' develop divergent patterns of fat distribution. Central to this process is the recurrent rise in the cerebral energy need (arousal) that non-habituators experience during chronic stress. These neuroenergetic alterations promote visceral fat accumulation, subcutaneous fat loss, and atherogenesis with subsequent cardiovascular events. Habituators are more or less protected against such cardiovascular complications, but there is a metabolic trade-off that we shall discuss in the present paper. PMID:26148986

  16. Habituation as a determinant of human food intake

    PubMed Central

    Epstein, Leonard H.; Temple, Jennifer L.; Roemmich, James N.; Bouton, Mark E.

    2009-01-01

    Research has shown that animals and humans habituate on a variety of behavioral and physiological responses to repeated presentations of food cues, and habituation is related to amount of food consumed and cessation of eating. The purpose of this article is to provide an overview of experimental paradigms used to study habituation, integrate a theoretical approach to habituation to food based on memory and associative conditioning models, and review research on factors that influence habituation. Individual differences in habituation as they related to obesity and eating disorders are reviewed, along with research on how individual differences in memory can influence habituation. Other associative conditioning approaches to ingestive behavior are reviewed, as well as how habituation provides novel approaches to preventing or treating obesity. Finally, new directions for habituation research are presented. Habituation provides a novel theoretical framework from which to understand factors that regulate ingestive behavior. PMID:19348547

  17. The first juvenile specimens of Plateosaurus engelhardti from Frick, Switzerland: isolated neural arches and their implications for developmental plasticity in a basal sauropodomorph

    PubMed Central

    Sander, P. Martin

    2014-01-01

    The dinosaur Plateosaurus engelhardti is the most abundant dinosaur in the Late Triassic of Europe and the best known basal sauropodomorph. Plateosaurus engelhardti was one of the first sauropodomorph dinosaurs to display a large body size. Remains can be found in the Norian stage of the Late Triassic in over 40 localities in Central Europe (France, Germany, and Switzerland) and in Greenland. Since the first discovery of P. engelhardti no juvenile specimens of this species had been described in detail. Here we describe the first remains of juvenile individuals, isolated cervical and dorsal neural arches from Switzerland. These were separated postmortem from their respective centra because of unfused neurocentral sutures. However the specimens share the same neural arch morphology found in adults. Morphometric analysis suggests body lengths of the juvenile individuals that is greater than those of most adult specimens. This supports the hypothesis of developmental plasticity in Plateosaurus engelhardti that previously had been based on histological data only. Alternative hypotheses for explaining the poor correlation between ontogenetic stage and size in this taxon are multiple species or sexual morphs with little morphological variance or time-averaging of individuals from populations differing in body size. PMID:25071987

  18. Synergistic effects of transplanted adult neural stem/progenitor cells, chondroitinase, and growth factors promote functional repair and plasticity of the chronically injured spinal cord.

    PubMed

    Karimi-Abdolrezaee, Soheila; Eftekharpour, Eftekhar; Wang, Jian; Schut, Desiree; Fehlings, Michael G

    2010-02-01

    The transplantation of neural stem/progenitor cells (NPCs) is a promising therapeutic strategy for spinal cord injury (SCI). However, to date NPC transplantation has exhibited only limited success in the treatment of chronic SCI. Here, we show that chondroitin sulfate proteoglycans (CSPGs) in the glial scar around the site of chronic SCI negatively influence the long-term survival and integration of transplanted NPCs and their therapeutic potential for promoting functional repair and plasticity. We targeted CSPGs in the chronically injured spinal cord by sustained infusion of chondroitinase ABC (ChABC). One week later, the same rats were treated with transplants of NPCs and transient infusion of growth factors, EGF, bFGF, and PDGF-AA. We demonstrate that perturbing CSPGs dramatically optimizes NPC transplantation in chronic SCI. Engrafted NPCs successfully integrate and extensively migrate within the host spinal cord and principally differentiate into oligodendrocytes. Furthermore, this combined strategy promoted the axonal integrity and plasticity of the corticospinal tract and enhanced the plasticity of descending serotonergic pathways. These neuroanatomical changes were also associated with significantly improved neurobehavioral recovery after chronic SCI. Importantly, this strategy did not enhance the aberrant synaptic connectivity of pain afferents, nor did it exacerbate posttraumatic neuropathic pain. For the first time, we demonstrate key biological and functional benefits for the combined use of ChABC, growth factors, and NPCs to repair the chronically injured spinal cord. These findings could potentially bring us closer to the application of NPCs for patients suffering from chronic SCI or other conditions characterized by the formation of a glial scar. PMID:20130176

  19. Interaction Between Optical and Neural Factors Affecting Visual Performance

    NASA Astrophysics Data System (ADS)

    Sabesan, Ramkumar

    The human eye suffers from higher order aberrations, in addition to conventional spherical and cylindrical refractive errors. Advanced optical techniques have been devised to correct them in order to achieve superior retinal image quality. However, vision is not completely defined by the optical quality of the eye, but also depends on how the image quality is processed by the neural system. In particular, how neural processing is affected by the past visual experience with optical blur has remained largely unexplored. The objective of this thesis was to investigate the interaction of optical and neural factors affecting vision. To achieve this goal, pathological keratoconic eyes were chosen as the ideal population to study since they are severely afflicted by degraded retinal image quality due to higher order aberrations and their neural system has been exposed to that habitually for a long period of time. Firstly, we have developed advanced customized ophthalmic lenses for correcting the higher order aberration of keratoconic eyes and demonstrated their feasibility in providing substantial visual benefit over conventional corrective methodologies. However, the achieved visual benefit was significantly smaller than that predicted optically. To better understand this, the second goal of the thesis was set to investigate if the neural system optimizes its underlying mechanisms in response to the long-term visual experience with large magnitudes of higher order aberrations. This study was facilitated by a large-stroke adaptive optics vision simulator, enabling us to access the neural factors in the visual system by manipulating the limit imposed by the optics of the eye. Using this instrument, we have performed a series of experiments to establish that habitual exposure to optical blur leads to an alteration in neural processing thereby alleviating the visual impact of degraded retinal image quality, referred to as neural compensation. However, it was also found that

  20. Postural dynamics and habituation to seasickness.

    PubMed

    Tal, Dror; Bar, Ronen; Nachum, Zohar; Gil, Amnon; Shupak, Avi

    2010-07-26

    The computerized dynamic posturography (CDP) test examines the response pattern to simultaneous, multimodal sensory stimulation. The purpose of this prospective, controlled study was to investigate whether postural dynamics evaluated by CDP are related to seasickness severity and the process of habituation to sea conditions. Subjects included 74 naval personnel assigned to service aboard ship and 29 controls designated for shore-based positions. Study participants performed a baseline CDP test, and subsequent follow-up examinations 6 and 12 months after completion of their training. On those occasions they also completed a seasickness severity questionnaire. Longitudinal changes in postural parameters were examined, as well as a possible correlation between baseline CDP results and final seasickness severity scores. The results indicated longitudinal habituation to seasickness. Reduced scores were found for sensory organization sub-tests 3 and 5 in the first follow-up examination, reflecting increased weighting of visual and somatosensory input in the maintenance of balance. Scores in the second follow-up examination were above baseline values, indicating increased reliance on vestibular cues. These significant bimodal changes were found only in study subjects having the highest degree of habituation to seasickness. A significant decrease in motor response strength was found in parallel with increased habituation to seasickness. Baseline CDP results and postural control dynamics were not correlated with subjects' final seasickness severity score. These results suggest a potential role for CDP in monitoring the process of habituation to unusual motion conditions. PMID:20493235

  1. Habituation of motion sickness in the cat

    NASA Technical Reports Server (NTRS)

    Crampton, George H.; Lucot, James B.

    1991-01-01

    Thirty femal cats were subjected to a motion sickness stimulus in three series of tests. A series consisted of five tests given biweekly, weekly, or daily. Each test consisted of 30 min of stimulation followed by 1 min of rest, and series were separated by a period of not less than 14 d. Retching was the dependent variable. No habituation (reduction in the incidence of retching) was found with biweekly testing but pronounced habituation was observed with weekly and daily testing. The 30 cats were divided evenly into high and low susceptibility groups based on the results of the biweekly tests. The rate of habituation was the same for the two susceptibility groups in both the weekly and daily series.

  2. Habitual control of goal selection in humans

    PubMed Central

    Cushman, Fiery; Morris, Adam

    2015-01-01

    Humans choose actions based on both habit and planning. Habitual control is computationally frugal but adapts slowly to novel circumstances, whereas planning is computationally expensive but can adapt swiftly. Current research emphasizes the competition between habits and plans for behavioral control, yet many complex tasks instead favor their integration. We consider a hierarchical architecture that exploits the computational efficiency of habitual control to select goals while preserving the flexibility of planning to achieve those goals. We formalize this mechanism in a reinforcement learning setting, illustrate its costs and benefits, and experimentally demonstrate its spontaneous application in a sequential decision-making task. PMID:26460050

  3. Reading in the dark: neural correlates and cross-modal plasticity for learning to read entire words without visual experience.

    PubMed

    Sigalov, Nadine; Maidenbaum, Shachar; Amedi, Amir

    2016-03-01

    Cognitive neuroscience has long attempted to determine the ways in which cortical selectivity develops, and the impact of nature vs. nurture on it. Congenital blindness (CB) offers a unique opportunity to test this question as the brains of blind individuals develop without visual experience. Here we approach this question through the reading network. Several areas in the visual cortex have been implicated as part of the reading network, and one of the main ones among them is the VWFA, which is selective to the form of letters and words. But what happens in the CB brain? On the one hand, it has been shown that cross-modal plasticity leads to the recruitment of occipital areas, including the VWFA, for linguistic tasks. On the other hand, we have recently demonstrated VWFA activity for letters in contrast to other visual categories when the information is provided via other senses such as touch or audition. Which of these tasks is more dominant? By which mechanism does the CB brain process reading? Using fMRI and visual-to-auditory sensory substitution which transfers the topographical features of the letters we compare reading with semantic and scrambled conditions in a group of CB. We found activation in early auditory and visual cortices during the early processing phase (letter), while the later phase (word) showed VWFA and bilateral dorsal-intraparietal activations for words. This further supports the notion that many visual regions in general, even early visual areas, also maintain a predilection for task processing even when the modality is variable and in spite of putative lifelong linguistic cross-modal plasticity. Furthermore, we find that the VWFA is recruited preferentially for letter and word form, while it was not recruited, and even exhibited deactivation, for an immediately subsequent semantic task suggesting that despite only short sensory substitution experience orthographic task processing can dominate semantic processing in the VWFA. On a wider

  4. The intimate relationship of gonadotropin-releasing hormone neurons with the polysialylated neural cell adhesion molecule revisited across development and adult plasticity.

    PubMed

    Franceschini, Isabelle; Desroziers, Elodie; Caraty, Alain; Duittoz, Anne

    2010-12-01

    The neurohormone gonadotropin-releasing hormone (GnRH) is critical for all the aspects of reproductive life in vertebrates. GnRH is secreted by a small number of neurons dispersed within the preoptic-hypothalamic region. These neurons are derived from the embryonic olfactory pit. They then migrate along olfactory, vomeronasal and terminal nerves to their final destination. Classical approaches to study the regulation of GnRH secretion during the reproductive cycle have focused on the various neuronal inputs on GnRH neurons and their regulation by ovarian steroids. However, it is well known that steroids will change the microenvironment of neuronal networks and can induce plasticity and functional changes. In this review, we will focus on the intimate relationship of developing and adult GnRH neurons with the polysialylated form of neural cell adhesion molecule (PSA-NCAM), a major molecular actor in the morphogenesis and adult plasticity of the nervous system. We will first recapitulate the spatiotemporal relationship between PSA-NCAM and migrating GnRH neurons during embryogenesis of various vertebrate species and discuss its importance for GnRH neuron development as shown by various loss of function studies. In the adult, we will review the relationships between PSA-NCAM and GnRH neurons across various physiological states, and open the discussion to the use of new model systems that can help to unravel the function and mechanism of action of PSA-NCAM on GnRH neuronal network activity and GnRH release. PMID:21143658

  5. High neuronal/astroglial differentiation plasticity of adult rat hippocampal neural stem/progenitor cells in response to the effects of embryonic and adult cerebrospinal fluids

    PubMed Central

    Peirouvi, T.; Yekani, F.; Azarnia, M.; Massumi, M.

    2015-01-01

    Hippocampal neural stem/progenitor cells (hipp-NS/PCs) of the adult mammalian brain are important sources of neuronal and gial cell production. In this study, the main goal is to investigate the plasticity of these cells in neuronal/astroglial differentiations. To this end, the differentiation of the hipp-NS/PCs isolated from 3-month-old Wistar rats was investigated in response to the embryonic cerebrospinal fluid (E-CSF) including E13.5, E17-CSF and the adult cerebrospinal fluid (A-CSF), all extracted from rats. CSF samples were selected based on their effects on cell behavioral parameters. Primary cell culture was performed in the presence of either normal or high levels of KCL in a culture medium. High levels of KCL cause cell depolarization, and thus the activation of quiescent NSCs. Results from immunocytochemistry (ICC) and semi-quantitative RT-PCR (sRT-PCR) techniques showed that in E-CSF-treated groups, neuronal differentiation increased (E17>E13.5). In contrast, A-CSF decreased and increased neuronal and astroglial differentiations, respectively. Cell survivability and/or proliferation (S/P), evaluated by an MTT assay, increased by E13.5 CSF, but decreased by both E17 CSF and A-CSF. Based on the results, it is finally concluded that adult rat hippocampal proliferative cells are not restricted progenitors but rather show high plasticity in neuronal/astroglial differentiation according to the effects of CSF samples. In addition, using high concentrations of KCL in the primary cell culture led to an increase in the number of NSCs, which in turn resulted in the increase in neuronal or astroglial differentiations after CSF treatment. PMID:27175157

  6. Short-Term Memory in Habituation and Dishabituation

    ERIC Educational Resources Information Center

    Whitlow, Jesse William, Jr.

    1975-01-01

    The present research evaluated the refractorylike response decrement, as found in habituation of auditory evoked peripheral vasoconstriction in rabbits, to determine whether or not it represents a short-term habituation process distinct from effector fatigue or sensory adaptation. (Editor)

  7. Experience-dependent plasticity in the inferior colliculus: a site for visual calibration of the neural representation of auditory space in the barn owl.

    PubMed

    Brainard, M S; Knudsen, E I

    1993-11-01

    The optic tectum (homolog of the superior colliculus) contains mutually aligned neural maps of auditory and visual space. During development, the organization of the auditory map is guided by spatial information provided by vision: barn owls raised wearing prismatic spectacles, which optically shift the visual field and the visual map in the optic tectum, develop an auditory map that is shifted by an approximately equivalent amount, such that alignment between the two maps is preserved (Knudsen and Brainard, 1991). In this study we investigated whether this shift in the auditory map is intrinsic to the optic tectum or whether it reflects plasticity at an earlier stage in the auditory pathway. Owls were raised wearing prismatic spectacles that displaced the visual field by 23 degrees to the left or right. This manipulation alters the normal correspondence between locations in the visual field and interaural time difference (ITD), the primary cue for the azimuth of a sound source. In normal owls and in owls with at least 150 d of prism experience, extracellular unit recordings were used to assess the representations of ITD at anatomically and physiologically defined sites in the optic tectum and in the two prior stages of the auditory pathway, the external and central nuclei of the inferior colliculus (ICx and ICc). In the optic tectum of normal owls, the values of ITD to which units responded most strongly (best ITDs) varied systematically with the azimuths of unit visual receptive fields (VRFs). In the prism-reared owls, best ITDs were shifted from normal toward the values of ITD produced by sounds at the locations of the units' optically displaced VRFs. In the ICx of prism-reared owls, the representation of ITD also was shifted from normal, by an amount and in a direction that could completely account for the shift in ITD measured in the optic tectum. At some sites in the ICx, the shift in ITD tuning was apparent within the first 7-8 msec of the response; shifted

  8. Habituation to a stressor predicts adolescents' adiposity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background and Objectives: Stress is associated with gains in adiposity. One factor that determines how much stress is experienced is how quickly an adolescent reduces responding (habituates) across repeated stressors. The purpose of this study was to determine the association of body mass index pe...

  9. From episodic to habitual prospective memory: ERP-evidence for a linear transition

    PubMed Central

    Meier, Beat; Matter, Sibylle; Baumann, Brigitta; Walter, Stefan; Koenig, Thomas

    2014-01-01

    Performing a prospective memory task repeatedly changes the nature of the task from episodic to habitual. The goal of the present study was to investigate the neural basis of this transition. In two experiments, we contrasted event-related potentials (ERPs) evoked by correct responses to prospective memory targets in the first, more episodic part of the experiment with those of the second, more habitual part of the experiment. Specifically, we tested whether the early, middle, or late ERP-components, which are thought to reflect cue detection, retrieval of the intention, and post-retrieval processes, respectively, would be changed by routinely performing the prospective memory task. The results showed a differential ERP effect in the middle time window (450–650 ms post-stimulus). Source localization using low resolution brain electromagnetic tomography analysis suggests that the transition was accompanied by an increase of activation in the posterior parietal and occipital cortex. These findings indicate that habitual prospective memory involves retrieval processes guided more strongly by parietal brain structures. In brief, the study demonstrates that episodic and habitual prospective memory tasks recruit different brain areas. PMID:25071519

  10. Habituation as a Determinant of Human Food Intake

    ERIC Educational Resources Information Center

    Epstein, Leonard H.; Temple, Jennifer L.; Roemmich, James N.; Bouton, Mark E.

    2009-01-01

    Research has shown that animals and humans habituate on a variety of behavioral and physiological responses to repeated presentations of food cues, and habituation is related to amount of food consumed and cessation of eating. The purpose of this article is to provide an overview of experimental paradigms used to study habituation, integrate a…

  11. Fetal Habituation Performance: Gestational Age and Sex Effects

    ERIC Educational Resources Information Center

    McCorry, Noleen K.; Hepper, Peter G.

    2007-01-01

    Habituation is the decrement in response to repeated stimulation. Fetal habituation performance may reflect the functioning of the central nervous system (CNS) prenatally. However, basic characteristics of the prenatal habituation phenomena remain unclear, such as the relationship with gestational age (GA) and fetal sex. The current study…

  12. Using Dynamic Field Theory to Rethink Infant Habituation

    ERIC Educational Resources Information Center

    Schoner, Gregor; Thelen, Esther

    2006-01-01

    Much of what psychologists know about infant perception and cognition is based on habituation, but the process itself is still poorly understood. Here the authors offer a dynamic field model of infant visual habituation, which simulates the known features of habituation, including familiarity and novelty effects, stimulus intensity effects, and…

  13. Habituation of Backward Escape Swimming in the Marbled Crayfish.

    PubMed

    Kasuya, Azusa; Nagayama, Toshiki

    2016-02-01

    In the present study, we performed behavioral analyses of the habituation of backward escape swimming in the marbled crayfish, Procambarus fallax. Application of rapid mechanical stimulation to the rostrum elicited backward swimming following rapid abdominal flexion of crayfish. Response latency was very short-tens of msec-suggesting that backward swimming is mediated by MG neurons. When stimulation was repeated with 10 sec interstimulus intervals the MG-like tailflip did not occur, as the animals showed habituation. Retention of habituation was rather short, with most animals recovering from habituation within 10 min. Previous experience of habituation was remembered and animals habituated faster during a second series of experiments with similar repetitive stimuli. About half the number of stimulus trials was necessary to habituate in the second test compared to the first test. This promotion of habituation was observed in animals with delay periods of rest within 60 min following the first habituation. After 90 min of rest from the first habitation, animals showed a similar time course for the second habituation. With five stimuli at 15 min interval during 90 min of the rest, trained animals showed rapid habituation, indicating reinforcement of the memory of previous experiments. Crayfish also showed dishabituation when mechanical stimulation was applied to the tail following habituation. PMID:26853863

  14. Noise Trauma Induced Neural Plasticity Throughout the Auditory System of Mongolian Gerbils: Differences between Tinnitus Developing and Non-Developing Animals.

    PubMed

    Tziridis, Konstantin; Ahlf, Sönke; Jeschke, Marcus; Happel, Max F K; Ohl, Frank W; Schulze, Holger

    2015-01-01

    In this study, we describe differences between neural plasticity in auditory cortex (AC) of animals that developed subjective tinnitus (group T) after noise-induced hearing loss (NIHL) compared to those that did not [group non-tinnitus (NT)]. To this end, our analysis focuses on the input activity of cortical neurons based on the temporal and spectral analysis of local field potential (LFP) recordings and an in-depth analysis of auditory brainstem responses (ABR) in the same animals. In response to NIHL in NT animals we find a significant general reduction in overall cortical activity and spectral power as well as changes in all ABR wave amplitudes as a function of loudness. In contrast, T-animals show no significant change in overall cortical activity as assessed by root mean square analysis of LFP amplitudes, but a specific increase in LFP spectral power and in the amplitude of ABR wave V reflecting activity in the inferior colliculus (IC). Based on these results, we put forward a refined model of tinnitus prevention after NIHL that acts via a top-down global (i.e., frequency-unspecific) inhibition reducing overall neuronal activity in AC and IC, thereby counteracting NIHL-induced bottom-up frequency-specific neuroplasticity suggested in current models of tinnitus development. PMID:25713557

  15. Neural Plastic Effects of Working Memory Training Influenced by Self-perceived Stress in Stroke: A Case Illustration

    PubMed Central

    Leung, Ada W. S.; Barrett, Lauren M.; Butterworth, Darcy; Werther, Karin; Dawson, Deirdre R.; Brintnell, E. Sharon

    2016-01-01

    This case study examined the effects of auditory working memory (WM) training on neuroplastic changes in stroke survivors and how such effects might be influenced by self-perceived stress. Two participants with a history of stroke participated in the study. One of them had a higher level of self-perceived stress. Both participants underwent a course of auditory WM training and completed baseline and post-training assessments such as self-perceived stress, performance satisfaction questionnaires, behavioral task performance, and functional magnetic resonance imaging. They were trained on a computerized auditory WM task (n-back) 5 days a week for 6 weeks, for a total of 20 h. Participant 1 had high levels of perceived stress, both pre- and post-training, and showed improvement on the satisfaction aspect of functional engagement only. Participant 2 had lower levels of perceived stress and demonstrated improvements on all performance tasks. Neuroimaging results showed evidence of improved neural efficiency on the trained task for participant 2. The results shed light on the need to evaluate psychological influences, e.g., stress, when studying the neuroplastic changes in people with stroke. However, the case design approach and other factors that might have positively influenced outcomes mean that these results must be interpreted with a great deal of caution. Future studies using a larger sample are recommended to verify the findings. PMID:27625614

  16. Emergence of Resonances in Neural Systems: The Interplay between Adaptive Threshold and Short-Term Synaptic Plasticity

    PubMed Central

    Mejias, Jorge F.; Torres, Joaquin J.

    2011-01-01

    In this work we study the detection of weak stimuli by spiking (integrate-and-fire) neurons in the presence of certain level of noisy background neural activity. Our study has focused in the realistic assumption that the synapses in the network present activity-dependent processes, such as short-term synaptic depression and facilitation. Employing mean-field techniques as well as numerical simulations, we found that there are two possible noise levels which optimize signal transmission. This new finding is in contrast with the classical theory of stochastic resonance which is able to predict only one optimal level of noise. We found that the complex interplay between adaptive neuron threshold and activity-dependent synaptic mechanisms is responsible for this new phenomenology. Our main results are confirmed by employing a more realistic FitzHugh-Nagumo neuron model, which displays threshold variability, as well as by considering more realistic stochastic synaptic models and realistic signals such as poissonian spike trains. PMID:21408148

  17. Neural Plastic Effects of Working Memory Training Influenced by Self-perceived Stress in Stroke: A Case Illustration.

    PubMed

    Leung, Ada W S; Barrett, Lauren M; Butterworth, Darcy; Werther, Karin; Dawson, Deirdre R; Brintnell, E Sharon

    2016-01-01

    This case study examined the effects of auditory working memory (WM) training on neuroplastic changes in stroke survivors and how such effects might be influenced by self-perceived stress. Two participants with a history of stroke participated in the study. One of them had a higher level of self-perceived stress. Both participants underwent a course of auditory WM training and completed baseline and post-training assessments such as self-perceived stress, performance satisfaction questionnaires, behavioral task performance, and functional magnetic resonance imaging. They were trained on a computerized auditory WM task (n-back) 5 days a week for 6 weeks, for a total of 20 h. Participant 1 had high levels of perceived stress, both pre- and post-training, and showed improvement on the satisfaction aspect of functional engagement only. Participant 2 had lower levels of perceived stress and demonstrated improvements on all performance tasks. Neuroimaging results showed evidence of improved neural efficiency on the trained task for participant 2. The results shed light on the need to evaluate psychological influences, e.g., stress, when studying the neuroplastic changes in people with stroke. However, the case design approach and other factors that might have positively influenced outcomes mean that these results must be interpreted with a great deal of caution. Future studies using a larger sample are recommended to verify the findings. PMID:27625614

  18. Astrocytes: Orchestrating synaptic plasticity?

    PubMed

    De Pittà, M; Brunel, N; Volterra, A

    2016-05-26

    Synaptic plasticity is the capacity of a preexisting connection between two neurons to change in strength as a function of neural activity. Because synaptic plasticity is the major candidate mechanism for learning and memory, the elucidation of its constituting mechanisms is of crucial importance in many aspects of normal and pathological brain function. In particular, a prominent aspect that remains debated is how the plasticity mechanisms, that encompass a broad spectrum of temporal and spatial scales, come to play together in a concerted fashion. Here we review and discuss evidence that pinpoints to a possible non-neuronal, glial candidate for such orchestration: the regulation of synaptic plasticity by astrocytes. PMID:25862587

  19. Habituation: a non-associative learning rule design for spiking neurons and an autonomous mobile robots implementation.

    PubMed

    Cyr, André; Boukadoum, Mounir

    2013-03-01

    This paper presents a novel bio-inspired habituation function for robots under control by an artificial spiking neural network. This non-associative learning rule is modelled at the synaptic level and validated through robotic behaviours in reaction to different stimuli patterns in a dynamical virtual 3D world. Habituation is minimally represented to show an attenuated response after exposure to and perception of persistent external stimuli. Based on current neurosciences research, the originality of this rule includes modulated response to variable frequencies of the captured stimuli. Filtering out repetitive data from the natural habituation mechanism has been demonstrated to be a key factor in the attention phenomenon, and inserting such a rule operating at multiple temporal dimensions of stimuli increases a robot's adaptive behaviours by ignoring broader contextual irrelevant information. PMID:23385344

  20. Caffeine Promotes Global Spatial Processing in Habitual and Non-Habitual Caffeine Consumers

    PubMed Central

    Giles, Grace E.; Mahoney, Caroline R.; Brunyé, Tad T.; Taylor, Holly A.; Kanarek, Robin B.

    2013-01-01

    Information processing is generally biased toward global cues, often at the expense of local information. Equivocal extant data suggests that arousal states may accentuate either a local or global processing bias, at least partially dependent on the nature of the manipulation, task, and stimuli. To further differentiate the conditions responsible for such equivocal results we varied caffeine doses to alter physiological arousal states and measured their effect on tasks requiring the retrieval of local versus global spatial knowledge. In a double-blind, repeated-measures design, non-habitual (Experiment 1; N = 36, M = 42.5 ± 28.7 mg/day caffeine) and habitual (Experiment 2; N = 34, M = 579.5 ± 311.5 mg/day caffeine) caffeine consumers completed four test sessions corresponding to each of four caffeine doses (0, 100, 200, 400 mg). During each test session, participants consumed a capsule containing one of the three doses of caffeine or placebo, waited 60 min, and then completed two spatial tasks, one involving memorizing maps and one spatial descriptions. A spatial statement verification task tested local versus global spatial knowledge by differentially probing memory for proximal versus distal landmark relationships. On the map learning task, results indicated that caffeine enhanced memory for distal (i.e., global) compared to proximal (i.e., local) comparisons at 100 (marginal), 200, and 400 mg caffeine in non-habitual consumers, and marginally beginning at 200 mg caffeine in habitual consumers. On the spatial descriptions task, caffeine enhanced memory for distal compared to proximal comparisons beginning at 100 mg in non-habitual but not habitual consumers. We thus provide evidence that caffeine-induced physiological arousal amplifies global spatial processing biases, and these effects are at least partially driven by habitual caffeine consumption. PMID:24146646

  1. Socially learned habituation to human observers in wild chimpanzees.

    PubMed

    Samuni, Liran; Mundry, Roger; Terkel, Joseph; Zuberbühler, Klaus; Hobaiter, Catherine

    2014-07-01

    Habituation to human observers is an essential tool in animal behaviour research. Habituation occurs when repeated and inconsequential exposure to a human observer gradually reduces an animal's natural aversive response. Despite the importance of habituation, little is known about the psychological mechanisms facilitating it in wild animals. Although animal learning theory offers some account, the patterns are more complex in natural than in laboratory settings, especially in large social groups in which individual experiences vary and individuals influence each other. Here, we investigate the role of social learning during the habituation process of a wild chimpanzee group, the Waibira community of Budongo Forest, Uganda. Through post hoc hypothesis testing, we found that the immigration of two well-habituated, young females from the neighbouring Sonso community had a significant effect on the behaviour of non-habituated Waibira individuals towards human observers, suggesting that habituation is partially acquired via social learning. PMID:24500498

  2. Modification of Male Courtship Motivation by Olfactory Habituation via the GABAA Receptor in Drosophila melanogaster

    PubMed Central

    Tachibana, Shin-Ichiro; Touhara, Kazushige; Ejima, Aki

    2015-01-01

    A male-specific component, 11-cis-vaccenyl acetate (cVA) works as an anti-aphrodisiac pheromone in Drosophila melanogaster. The presence of cVA on a male suppresses the courtship motivation of other males and contributes to suppression of male-male homosexual courtship, while the absence of cVA on a female stimulates the sexual motivation of nearby males and enhances the male-female interaction. However, little is known how a male distinguishes the presence or absence of cVA on a target fly from either self-produced cVA or secondhand cVA from other males in the vicinity. In this study, we demonstrate that male flies have keen sensitivity to cVA; therefore, the presence of another male in the area reduces courtship toward a female. This reduced level of sexual motivation, however, could be overcome by pretest odor exposure via olfactory habituation to cVA. Real-time imaging of cVA-responsive sensory neurons using the neural activity sensor revealed that prolonged exposure to cVA decreased the levels of cVA responses in the primary olfactory center. Pharmacological and genetic screening revealed that signal transduction via GABAA receptors contributed to this olfactory habituation. We also found that the habituation experience increased the copulation success of wild-type males in a group. In contrast, transgenic males, in which GABA input in a small subset of local neurons was blocked by RNAi, failed to acquire the sexual advantage conferred by habituation. Thus, we illustrate a novel phenomenon in which olfactory habituation positively affects sexual capability in a competitive environment. PMID:26252206

  3. Dietary Variety Impairs Habituation in Children

    PubMed Central

    Temple, Jennifer L.; Giacomelli, April M.; Roemmich, James N.; Epstein, Leonard H.

    2008-01-01

    Objective The purpose of these studies was to test the hypothesis that dietary variety decreases the rate of habituation and increases energy intake in children. Design In Experiment 1, salivation in response to the same or a variety of food cues was measured followed by consumption of the study food(s). In Experiment 2, children responded in a computer task to earn points for the same or a variety of low or high energy density foods, which were then consumed. Main Outcome Measures Salivation, number of responses, and energy intake were measured. Results Participants in the same groups habituated faster than those in the variety groups (p < .05), and in Experiment 2, the effect of variety was independent of energy density. Participants in the variety groups also consumed more energy than those in the same groups in both experiments (p < .05). Conclusions Dietary variety disrupted habituation and increased energy intake in children. In addition, the response to dietary variety was independent of energy density, suggesting that increasing variety of low energy density foods may increase consumption. PMID:18248101

  4. Alaskan brown bears, humans, and habituation

    USGS Publications Warehouse

    Smith, Thomas; Herrero, Stephen; DeBruyn, Terry D.

    2005-01-01

    We present a new paradigm for understanding habituation and the role it plays in brown bear (Ursus arctos) populations and interactions with humans in Alaska. We assert that 3 forms of habituation occur in Alaska: bear-to-bear, bear-to-human, and human-to-bear. We present data that supports our theory that bear density is an important factor influencing a bear’s overt reaction distance (ORD); that as bear density increases, overt reaction distance decreases, as does the likelihood of bear– human interactions. We maintain that the effects of bear-to-bear habituation are largely responsible for not only shaping bear aggregations but also for creating the relatively safe environment for bear viewing experienced at areas where there are high densities of brown bears. By promoting a better understanding of the forces that shape bear social interactions within populations and with humans that mingle with them, we can better manage human activities and minimize bear–human conflict.

  5. Individual differences in the habitual use of cognitive reappraisal predict the reward-related processing.

    PubMed

    Sai, Liyang; Wang, Sisi; Ward, Anne; Ku, Yixuan; Sang, Biao

    2015-01-01

    Recent studies have shown that instructed cognitive reappraisal can regulate the neural processing of reward. However, it is still unclear whether the habitual use of cognitive reappraisal in everyday life is related to brain activity involved in reward processing. In the present study, participants' neural responses to reward were measured using electroencephalography (EEG) recorded during a gambling task and their tendency to use cognitive reappraisal was assessed using the Emotion Regulation Questionnaire (ERQ). Event-related potential (ERP) results indicated that losses on the gambling task elicited greater negative reward-related feedback negativity (FN) than gains. The differential FN between losses and gains was significantly correlated with cognitive reappraisal scores across participants such that individuals with a higher tendency to use cognitive reappraisal showed stronger reward processing (i.e., amplified FN difference between losses and gains). This correlation remained significant after controlling for expressive suppression scores. However, expressive suppression per se was not correlated with FN differences. Taken together, these results suggest that the habitual use of cognitive reappraisal is associated with increased neural processing of reward. PMID:26388796

  6. Individual differences in the habitual use of cognitive reappraisal predict the reward-related processing

    PubMed Central

    Sai, Liyang; Wang, Sisi; Ward, Anne; Ku, Yixuan; Sang, Biao

    2015-01-01

    Recent studies have shown that instructed cognitive reappraisal can regulate the neural processing of reward. However, it is still unclear whether the habitual use of cognitive reappraisal in everyday life is related to brain activity involved in reward processing. In the present study, participants’ neural responses to reward were measured using electroencephalography (EEG) recorded during a gambling task and their tendency to use cognitive reappraisal was assessed using the Emotion Regulation Questionnaire (ERQ). Event-related potential (ERP) results indicated that losses on the gambling task elicited greater negative reward-related feedback negativity (FN) than gains. The differential FN between losses and gains was significantly correlated with cognitive reappraisal scores across participants such that individuals with a higher tendency to use cognitive reappraisal showed stronger reward processing (i.e., amplified FN difference between losses and gains). This correlation remained significant after controlling for expressive suppression scores. However, expressive suppression per se was not correlated with FN differences. Taken together, these results suggest that the habitual use of cognitive reappraisal is associated with increased neural processing of reward. PMID:26388796

  7. Modeling novelty habituation during exploratory activity in Drosophila.

    PubMed

    Soibam, Benjamin; Shah, Shishir; Gunaratne, Gemunu H; Roman, Gregg W

    2013-07-01

    Habituation is a common form of non-associative learning in which the organism gradually decreases its response to repeated stimuli. The decrease in exploratory activity of many animal species during exposure to a novel open field arena is a widely studied habituation paradigm. However, a theoretical framework to quantify how the novelty of the arena is learned during habituation is currently missing. Drosophila melanogaster display a high mean absolute activity and a high probability for directional persistence when first introduced to a novel arena. Both measures decrease during habituation to the arena. Here, we propose a phenomenological model of habituation for Drosophila exploration based on two principles: Drosophila form a spatial representation of the arena edge as a set of connected local patches, and repeated exposure to these patches is essential for the habituation of the novelty. The level of exposure depends on the number of visitations and is quantified by a variable referred to as "coverage". This model was tested by comparing predictions against the experimentally measured behavior of wild type Drosophila. The novelty habituation of wild type Canton-S depends on coverage and is specifically independent of the arena radius. Our model describes the time dependent locomotor activity, ΔD, of Canton-S using an experimentally established stochastic process Pn(ΔD), which depends on the coverage. The quantitative measures of exploration and habituation were further applied to three mutant genotypes. Consistent with a requirement for vision in novelty habituation, blind no receptor potential A(7) mutants display a failure in the decay of probability for directional persistence and mean absolute activity. The rutabaga(2080) habituation mutant also shows defects in these measures. The kurtz(1) non-visual arrestin mutant demonstrates a rapid decay in these measures, implying reduced motivation. The model and the habituation measures offer a powerful

  8. Temporomandibular Disorders: The Habitual Chewing Side Syndrome

    PubMed Central

    Santana-Mora, Urbano; López-Cedrún, José; Mora, María J.; Otero, Xosé L.; Santana-Penín, Urbano

    2013-01-01

    Background Temporomandibular disorders are the most common cause of chronic orofacial pain, but, except where they occur subsequent to trauma, their cause remains unknown. This cross-sectional study assessed chewing function (habitual chewing side) and the differences of the chewing side and condylar path and lateral anterior guidance angles in participants with chronic unilateral temporomandibular disorder. This is the preliminary report of a randomized trial that aimed to test the effect of a new occlusal adjustment therapy. Methods The masticatory function of 21 randomly selected completely dentate participants with chronic temporomandibular disorders (all but one with unilateral symptoms) was assessed by observing them eat almonds, inspecting the lateral horizontal movement of the jaw, with kinesiography, and by means of interview. The condylar path in the sagittal plane and the lateral anterior guidance angles with respect to the Frankfort horizontal plane in the frontal plane were measured on both sides in each individual. Results Sixteen of 20 participants with unilateral symptoms chewed on the affected side; the concordance (Fisher’s exact test, P = .003) and the concordance-symmetry level (Kappa coefficient κ = 0.689; 95% confidence interval [CI], 0.38 to 0.99; P = .002) were significant. The mean condylar path angle was steeper (53.47(10.88) degrees versus 46.16(7.25) degrees; P = .001), and the mean lateral anterior guidance angle was flatter (41.63(13.35) degrees versus 48.32(9.53) degrees P = .036) on the symptomatic side. Discussion The results of this study support the use of a new term based on etiology, “habitual chewing side syndrome”, instead of the nonspecific symptom-based “temporomandibular joint disorders”; this denomination is characterized in adults by a steeper condylar path, flatter lateral anterior guidance, and habitual chewing on the symptomatic side. PMID:23593156

  9. Goal-directed, habitual and Pavlovian prosocial behavior

    PubMed Central

    Gęsiarz, Filip; Crockett, Molly J.

    2015-01-01

    Although prosocial behaviors have been widely studied across disciplines, the mechanisms underlying them are not fully understood. Evidence from psychology, biology and economics suggests that prosocial behaviors can be driven by a variety of seemingly opposing factors: altruism or egoism, intuition or deliberation, inborn instincts or learned dispositions, and utility derived from actions or their outcomes. Here we propose a framework inspired by research on reinforcement learning and decision making that links these processes and explains characteristics of prosocial behaviors in different contexts. More specifically, we suggest that prosocial behaviors inherit features of up to three decision-making systems employed to choose between self- and other- regarding acts: a goal-directed system that selects actions based on their predicted consequences, a habitual system that selects actions based on their reinforcement history, and a Pavlovian system that emits reflexive responses based on evolutionarily prescribed priors. This framework, initially described in the field of cognitive neuroscience and machine learning, provides insight into the potential neural circuits and computations shaping prosocial behaviors. Furthermore, it identifies specific conditions in which each of these three systems should dominate and promote other- or self- regarding behavior. PMID:26074797

  10. Habituation to painful stimulation involves the antinociceptive system.

    PubMed

    Bingel, U; Schoell, E; Herken, W; Büchel, C; May, A

    2007-09-01

    The perception of pain results from an interaction between nociceptive and antinociceptive mechanisms. A better understanding of the neural circuitry underlying these physiological interactions provides an important opportunity to develop better treatment strategies for and ultimately even prevent pain. Here, we investigated how repeated painful stimulation over several days is processed, perceived and finally modulated in the healthy human brain. Twenty healthy subjects were stimulated daily with a 20min pain paradigm for 8 consecutive days, and functional MRI performed on days 1, 8 and 22. Repeated painful stimulation over several days resulted in substantially decreased pain ratings to identical painful stimuli. The decreased perception of pain over time is reflected in decreased BOLD responses to nociceptive stimuli in classical pain areas, including thalamus, insula, SII and the putamen. In contrast to this finding, we found that pain-related responses in the rACC, specifically the subgenual anterior cingulate cortex (sgACC), significantly increased over time. Given this area's predominant role in endogenous pain control, this response pattern suggests that habituation to pain is at least in part mediated by increased antinociceptive activity. PMID:17258858

  11. The Habituation/Cross-Habituation Test Revisited: Guidance from Sniffing and Video Tracking

    PubMed Central

    Coronas-Samano, G.; Ivanova, A. V.

    2016-01-01

    The habituation/cross-habituation test (HaXha) is a spontaneous odor discrimination task that has been used for many decades to evaluate olfactory function in animals. Animals are presented repeatedly with the same odorant after which a new odorant is introduced. The time the animal explores the odor object is measured. An animal is considered to cross-habituate during the novel stimulus trial when the exploration time is higher than the prior trial and indicates the degree of olfactory patency. On the other hand, habituation across the repeated trials involves decreased exploration time and is related to memory patency, especially at long intervals. Classically exploration is timed using a stopwatch when the animal is within 2 cm of the object and aimed toward it. These criteria are intuitive, but it is unclear how they relate to olfactory exploration, that is, sniffing. We used video tracking combined with plethysmography to improve accuracy, avoid observer bias, and propose more robust criteria for exploratory scoring when sniff measures are not available. We also demonstrate that sniff rate combined with proximity is the most direct measure of odorant exploration and provide a robust and sensitive criterion. PMID:27516910

  12. Attentional Focus Moderates Habituation-Language Relationships: Slow Habituation May Be a Good Thing

    ERIC Educational Resources Information Center

    Dixon, Wallace E., Jr.; Smith, P. Hull

    2008-01-01

    An interesting paradox in the developmental literature has emerged in which fast-habituating babies tend to be temperamentally difficult and fast language learners, even though temperamentally difficult babies tend to be slow language learners. The purpose of the present investigation was to examine whether the paradoxical relationships among…

  13. MAGI-1 modulates AMPA receptor synaptic localization and behavioral plasticity in response to prior experience.

    PubMed

    Emtage, Lesley; Chang, Howard; Tiver, Rebecca; Rongo, Christopher

    2009-01-01

    It is well established that the efficacy of synaptic connections can be rapidly modified by neural activity, yet how the environment and prior experience modulate such synaptic and behavioral plasticity is only beginning to be understood. Here we show in C. elegans that the broadly conserved scaffolding molecule MAGI-1 is required for the plasticity observed in a glutamatergic circuit. This mechanosensory circuit mediates reversals in locomotion in response to touch stimulation, and the AMPA-type receptor (AMPAR) subunits GLR-1 and GLR-2, which are required for reversal behavior, are localized to ventral cord synapses in this circuit. We find that animals modulate GLR-1 and GLR-2 localization in response to prior mechanosensory stimulation; a specific isoform of MAGI-1 (MAGI-1L) is critical for this modulation. We show that MAGI-1L interacts with AMPARs through the intracellular domain of the GLR-2 subunit, which is required for the modulation of AMPAR synaptic localization by mechanical stimulation. In addition, mutations that prevent the ubiquitination of GLR-1 prevent the decrease in AMPAR localization observed in previously stimulated magi-1 mutants. Finally, we find that previously-stimulated animals later habituate to subsequent mechanostimulation more rapidly compared to animals initially reared without mechanical stimulation; MAGI-1L, GLR-1, and GLR-2 are required for this change in habituation kinetics. Our findings demonstrate that prior experience can cause long-term alterations in both behavioral plasticity and AMPAR localization at synapses in an intact animal, and indicate a new, direct role for MAGI/S-SCAM proteins in modulating AMPAR localization and function in the wake of variable sensory experience. PMID:19242552

  14. Reduced habituation of auditory evoked potentials indicate cortical hyper-excitability in Fragile X Syndrome.

    PubMed

    Ethridge, L E; White, S P; Mosconi, M W; Wang, J; Byerly, M J; Sweeney, J A

    2016-01-01

    Sensory hypersensitivities are common, clinically distressing features of Fragile X Syndrome (FXS). Preclinical evidence suggests this abnormality may result from synaptic hyper-excitability in sensory systems. This model predicts reduced sensory habituation to repeated stimulus presentation. Fourteen adolescents and adults with FXS and 15 age-matched controls participated in a modified auditory gating task using trains of 4 identical tones during dense array electroencephalography (EEG). Event-related potential and single trial time-frequency analyses revealed decreased habituation of the N1 event-related potential response in FXS, and increased gamma power coupled with decreases in gamma phase-locking during the early-stimulus registration period. EEG abnormalities in FXS were associated with parent reports of heightened sensory sensitivities and social communication deficits. Reduced habituation and altered gamma power and phase-locking to auditory cues demonstrated here in FXS patients parallels preclinical findings with Fmr1 KO mice. Thus, the EEG abnormalities seen in FXS patients support the model of neocortical hyper-excitability in FXS, and may provide useful translational biomarkers for evaluating novel treatment strategies targeting its neural substrate. PMID:27093069

  15. Saliency mapping in the optic tectum and its relationship to habituation.

    PubMed

    Dutta, Arkadeb; Gutfreund, Yoram

    2014-01-01

    Habituation of the orienting response has long served as a model system for studying fundamental psychological phenomena such as learning, attention, decisions, and surprise. In this article, we review an emerging hypothesis that the evolutionary role of the superior colliculus (SC) in mammals or its homolog in birds, the optic tectum (OT), is to select the most salient target and send this information to the appropriate brain regions to control the body and brain orienting responses. Recent studies have begun to reveal mechanisms of how saliency is computed in the OT/SC, demonstrating a striking similarity between mammals and birds. The saliency of a target can be determined by how different it is from the surrounding objects, by how different it is from its history (that is habituation) and by how relevant it is for the task at hand. Here, we will first review evidence, mostly from primates and barn owls, that all three types of saliency computations are linked in the OT/SC. We will then focus more on neural adaptation in the OT and its possible link to temporal saliency and habituation. PMID:24474908

  16. Reduced habituation of auditory evoked potentials indicate cortical hyper-excitability in Fragile X Syndrome

    PubMed Central

    Ethridge, L E; White, S P; Mosconi, M W; Wang, J; Byerly, M J; Sweeney, J A

    2016-01-01

    Sensory hypersensitivities are common, clinically distressing features of Fragile X Syndrome (FXS). Preclinical evidence suggests this abnormality may result from synaptic hyper-excitability in sensory systems. This model predicts reduced sensory habituation to repeated stimulus presentation. Fourteen adolescents and adults with FXS and 15 age-matched controls participated in a modified auditory gating task using trains of 4 identical tones during dense array electroencephalography (EEG). Event-related potential and single trial time–frequency analyses revealed decreased habituation of the N1 event-related potential response in FXS, and increased gamma power coupled with decreases in gamma phase-locking during the early-stimulus registration period. EEG abnormalities in FXS were associated with parent reports of heightened sensory sensitivities and social communication deficits. Reduced habituation and altered gamma power and phase-locking to auditory cues demonstrated here in FXS patients parallels preclinical findings with Fmr1 KO mice. Thus, the EEG abnormalities seen in FXS patients support the model of neocortical hyper-excitability in FXS, and may provide useful translational biomarkers for evaluating novel treatment strategies targeting its neural substrate. PMID:27093069

  17. Saliency mapping in the optic tectum and its relationship to habituation

    PubMed Central

    Dutta, Arkadeb; Gutfreund, Yoram

    2014-01-01

    Habituation of the orienting response has long served as a model system for studying fundamental psychological phenomena such as learning, attention, decisions, and surprise. In this article, we review an emerging hypothesis that the evolutionary role of the superior colliculus (SC) in mammals or its homolog in birds, the optic tectum (OT), is to select the most salient target and send this information to the appropriate brain regions to control the body and brain orienting responses. Recent studies have begun to reveal mechanisms of how saliency is computed in the OT/SC, demonstrating a striking similarity between mammals and birds. The saliency of a target can be determined by how different it is from the surrounding objects, by how different it is from its history (that is habituation) and by how relevant it is for the task at hand. Here, we will first review evidence, mostly from primates and barn owls, that all three types of saliency computations are linked in the OT/SC. We will then focus more on neural adaptation in the OT and its possible link to temporal saliency and habituation. PMID:24474908

  18. Neonatal Habituation and Dishabituation to Tactile Stimulation during Sleep.

    ERIC Educational Resources Information Center

    Kisilevsky, Barbara S.; Muir, Darwin W.

    1984-01-01

    Two experiments were conducted to (1) replicate the findings of habituation of behavioral responding to a tactile stimulus assuring state control and (2) demonstrate dishabituation either by reinstatement of responding to the original, habituated stimulus or to novel stimuli either within or between modalities. Subjects were newborn Caucasian…

  19. Interspeaker Variation in Habitual Speaking Rate: Additional Evidence

    ERIC Educational Resources Information Center

    Tsao, Ying-Chiao; Weismer, Gary; Iqbal, Kamran

    2006-01-01

    Purpose: The purpose of the present study was to test the hypothesis that talkers previously classified by Y.-C. Tsao and G. Weismer (1997) as habitually fast versus habitually slow would show differences in the way they manipulated articulation rate across the rate continuum. Method: Thirty talkers previously classified by Tsao and Weismer (1997)…

  20. Protection from Premature Habituation Requires Functional Mushroom Bodies in "Drosophila"

    ERIC Educational Resources Information Center

    Acevedo, Summer F.; Froudarakis, Emmanuil I.; Kanellopoulos, Alexandros; Skoulakis, Efthimios M. C.

    2007-01-01

    Diminished responses to stimuli defined as habituation can serve as a gating mechanism for repetitive environmental cues with little predictive value and importance. We demonstrate that wild-type animals diminish their responses to electric shock stimuli with properties characteristic of short- and long-term habituation. We used spatially…

  1. Infant Temperament and Subject Loss in a Habituation Procedure.

    ERIC Educational Resources Information Center

    Wachs, Theodore D.; Smitherman, Colleen H.

    1985-01-01

    A total of 114 infants at three age levels (11, 18, and 28 weeks) were rated by their mothers on a termperament questionnaire and subjected to a habituation procedure. Results suggest that subject loss in habituation studies may be the result of nonrandom individual difference factors and not just the result of temporary fluctuations in state.…

  2. [Prevention of habitual abortion by buffycoat transfusions].

    PubMed

    Neumeyer, H; Kuhn, W; Götze, O; Hinney, B

    1985-01-01

    From an immunological point of view the product of pregnancy may be regarded as a haplo-different allotransplant. A system possibly closely linked to the HLA-region is postulated to lead to the immunological recognition of the fetus by the mother and, paradoxically, to a take of the "transplant". The postulated system apparently codes for antigens present on both trophoblast and adult lymphocytes (TLX = trophoblast-lymphocyte-crossreacting). The prevention of rejection is thought to be effected by blocking factors (BF) present in the serum or plasma of the mother. There may be different kinds of BF: a specific BF (detectable only in an autologous assay system), appearing late in pregnancy, which inhibits several lymphocyte-dependent reactions (e.g. production of MIF, MLC). This BF has been identified as an IgG-class antibody. a nonspecific BF, appearing early in pregnancy which inhibits the MLC in vitro. c) may be a third BF, also specific, which is found only in plasma but not in serum. All described BF-activities were absent in women with habitual abortions. HLA-identity or partial identity could imply TLX-identity. The consequence of such an identity could be: non-detection of the trophoblast by the immune system of the mother, no production of BF, abortion. However several investigators could not find any HLA-identity of the partners with habitual abortions. A protective effect on the fetus has been seen when pregnant women were immunised with adult leukocytes, using either buffycoats from various HLA-different but bloodgroup-compatible donors or isolated leukocytes from the spouse.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:4072314

  3. Adult myelination: wrapping up neuronal plasticity

    PubMed Central

    O’Rourke, Megan; Gasperini, Robert; Young, Kaylene M.

    2014-01-01

    In this review, we outline the major neural plasticity mechanisms that have been identified in the adult central nervous system (CNS), and offer a perspective on how they regulate CNS function. In particular we examine how myelin plasticity can operate alongside neurogenesis and synaptic plasticity to influence information processing and transfer in the mature CNS. PMID:25221576

  4. Habituation of LG-mediated tailflip in the crayfish.

    PubMed

    Nagayama, Toshiki; Araki, Makoto

    2015-06-01

    Crayfish escape from threatening stimuli by tailflipping. If a stimulus is applied to the rear, crayfish escape up and forwards in a summersault maneuver that is mediated by the activation of lateral giant (LG) interneurons. The occurrence probability of LG-mediated tailflip, however, diminishes and habituates if a stimulus is repeatedly applied. Since crayfish have a relatively simple CNS with many identifiable neurons, crayfish represent a good animal to analyze the cellular basis of habituation. A reduction in the amplitude of the EPSP in the LGs, caused by direct chemical synaptic connection from sensory afferents by repetitive stimulations, is essential to bring about an inactivation of the LGs. The spike response of the LGs recovers within several minutes of habituation, but the LGs subsequently fail to spike when an additional stimulus is applied after specific periods following habituation. These results indicate that a decline in synaptic efficacy from the mechanosensory afferents recovers readily after a short delay, but then the excitability of the LGs themselves decreases. Furthermore, the processes underlying habituation are modulated depending on a social status. When two crayfish encounter each other, a winner-loser relationship is established. With a short interstimulus interval of 5 s, the rate of habituation of the LG in both socially dominant and subordinate crayfish becomes lower than in socially isolated animals. Serotonin and octopamine affect this social status-dependent modulation of habituation by means of activation of downstream second messenger system of cAMP and IP3 cascades, respectively. PMID:25796506

  5. Plastic Surgery

    MedlinePlus

    ... How Can I Help a Friend Who Cuts? Plastic Surgery KidsHealth > For Teens > Plastic Surgery Print A ... her forehead lightened with a laser? What Is Plastic Surgery? Just because the name includes the word " ...

  6. Sensory specific satiety: More than 'just' habituation?

    PubMed

    Wilkinson, Laura L; Brunstrom, Jeffrey M

    2016-08-01

    Sensory specific satiety (SSS) describes the decline in pleasantness associated with a food as it is eaten relative to a food that has not been eaten (the 'eaten' and 'uneaten' foods, respectively). The prevailing view is that SSS is governed by habituation. Nevertheless, the extent to which SSS results solely from this 'low-level' process remains unclear. Three experiments were conducted to explore the hypothesis that 'top-down' cognitive activity affects the expression of SSS; specifically, we manipulated participants' expectations about whether or not they would have access to alternative test foods (uneaten foods) after consuming a test meal (eaten food). This manipulation was motivated by 'Commodity Theory,' which describes the relative increase in value of a commodity when it becomes unavailable. We tested the hypothesis that a decline in the pleasantness and desire to eat the eaten food is exaggerated when uneaten foods are unavailable to participants. None of our findings supported this proposition - we found no evidence that SSS is dependent on top-down processes associated with the availability of other uneaten test foods. PMID:27105584

  7. Relationship between food habituation and reinforcing efficacy of food

    PubMed Central

    Carr, Katelyn A.; Epstein, Leonard H.

    2011-01-01

    Reinforcing value and habituation are two processes that have been used to study eating behaviors, but no research has examined their relationship, how they relate to energy intake, and whether they respond in a similar manner to food deprivation. Twenty-two female subjects were randomized to food deprived or non-deprived conditions, and assessed for food reinforcement, habituation to food and ad libitum eating. Results showed food reinforcement and habituation are correlated (r = 0.62, p = 0.002) and both independently predict energy intake. Hierarchical regression showed that the rate of habituation accounted for 30 percent of the variance in eating (p = 0.008), and adding food reinforcement increased the amount of variance accounted for up to 57.5 percent (p < 0.05). This suggests that both processes may influence energy intake in a meal. PMID:21423567

  8. Computing with Neural Synchrony

    PubMed Central

    Brette, Romain

    2012-01-01

    Neurons communicate primarily with spikes, but most theories of neural computation are based on firing rates. Yet, many experimental observations suggest that the temporal coordination of spikes plays a role in sensory processing. Among potential spike-based codes, synchrony appears as a good candidate because neural firing and plasticity are sensitive to fine input correlations. However, it is unclear what role synchrony may play in neural computation, and what functional advantage it may provide. With a theoretical approach, I show that the computational interest of neural synchrony appears when neurons have heterogeneous properties. In this context, the relationship between stimuli and neural synchrony is captured by the concept of synchrony receptive field, the set of stimuli which induce synchronous responses in a group of neurons. In a heterogeneous neural population, it appears that synchrony patterns represent structure or sensory invariants in stimuli, which can then be detected by postsynaptic neurons. The required neural circuitry can spontaneously emerge with spike-timing-dependent plasticity. Using examples in different sensory modalities, I show that this allows simple neural circuits to extract relevant information from realistic sensory stimuli, for example to identify a fluctuating odor in the presence of distractors. This theory of synchrony-based computation shows that relative spike timing may indeed have computational relevance, and suggests new types of neural network models for sensory processing with appealing computational properties. PMID:22719243

  9. Dynamic role of postsynaptic caspase-3 and BIRC4 in zebra finch song-response habituation.

    PubMed

    Huesmann, Graham R; Clayton, David F

    2006-12-21

    Activation of the protease caspase-3 is commonly thought to cause apoptotic cell death. Here, we show that caspase-3 activity is regulated at postsynaptic sites in brain following stimuli associated with memory (neural activation and subsequent response habituation) instead of cell death. In the zebra finch auditory forebrain, the concentration of caspase-3 active sites increases briefly within minutes after exposure to tape-recorded birdsong. With confocal and immunoelectron microscopy, we localize the activated enzyme to dendritic spines. The activated caspase-3 protein is present even in unstimulated brain but bound to an endogenous inhibitor, BIRC4 (xIAP), suggesting a mechanism for rapid release and sequestering at specific synaptic sites. Caspase-3 activity is necessary to consolidate a persistent physiological trace of the song stimulus, as demonstrated using pharmacological interference and the zenk gene habituation assay. Thus, the brain appears to have adapted a core component of cell death machinery to serve a unique role in learning and memory. PMID:17178408

  10. One night of partial sleep deprivation affects habituation of hypothalamus and skin conductance responses.

    PubMed

    Peters, Anja C; Blechert, Jens; Sämann, Philipp G; Eidner, Ines; Czisch, Michael; Spoormaker, Victor I

    2014-09-15

    Sleep disturbances are prevalent in clinical anxiety, but it remains unclear whether they are cause and/or consequence of this condition. Fear conditioning constitutes a valid laboratory model for the acquisition of normal and pathological anxiety. To explore the relationship between disturbed sleep and anxiety in more detail, the present study evaluated the effect of partial sleep deprivation (SD) on fear conditioning in healthy individuals. The neural correlates of 1) nonassociative learning and physiological processing and 2) associative learning (differential fear conditioning) were addressed. Measurements entailed simultaneous functional MRI, EEG, skin conductance response (SCR), and pulse recordings. Regarding nonassociative learning, partial SD resulted in a generalized failure to habituate during fear conditioning, as evidenced by reduced habituation of SCR and hypothalamus responses to all stimuli. Furthermore, SCR and hypothalamus activity were correlated, supporting their functional relationship. Regarding associative learning, effects of partial SD on the acquisition of conditioned fear were weaker and did not reach statistical significance. The hypothalamus plays an integral role in the regulation of sleep and autonomic arousal. Thus sleep disturbances may play a causal role in the development of normal and possibly pathological fear by increasing the susceptibility of the sympathetic nervous system to stressful experiences. PMID:24920020