The Experts below are selected from a list of 52269 Experts worldwide ranked by ideXlab platform
Thomas Wichmann - One of the best experts on this subject based on the ideXlab platform.
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Basal Ganglia circuits as targets for neuromodulation in parkinson disease
JAMA Neurology, 2015Co-Authors: Mahlon R Delong, Thomas WichmannAbstract:Importance The revival of stereotactic surgery for Parkinson disease (PD) in the 1990s, with pallidotomy and then with high-frequency deep brain stimulation (DBS), has led to a renaissance in functional surgery for movement and other neuropsychiatric disorders. Objective To examine the scientific foundations and rationale for the use of ablation and DBS for treatment of neurologic and psychiatric diseases, using PD as the primary example. Evidence Review A summary of the large body of relevant literature is presented on anatomy, physiology, pathophysiology, and functional surgery for PD and other Basal Ganglia disorders. Findings The signs and symptoms of movement disorders appear to result largely from signature abnormalities in one of several parallel and largely segregated Basal Ganglia thalamocortical circuits (ie, the motor circuit). The available evidence suggests that the varied movement disorders resulting from dysfunction of this circuit result from propagated disruption of downstream network activity in the thalamus, cortex, and brainstem. Ablation and DBS act to free downstream networks to function more normally. The Basal Ganglia thalamocortical circuit may play a key role in the expression of disordered movement, and the Basal Ganglia–brainstem projections may play roles in akinesia and disturbances of gait. Efforts are under way to target circuit dysfunction in brain areas outside of the traditionally implicated Basal Ganglia thalamocortical system, in particular, the pedunculopontine nucleus, to address gait disorders that respond poorly to levodopa and conventional DBS targets. Conclusions and Relevance Deep brain stimulation is now the treatment of choice for many patients with advanced PD and other movement disorders. The success of DBS and other forms of neuromodulation for neuropsychiatric disorders is the result of the ability to modulate circuit activity in discrete functional domains within the Basal Ganglia circuitry with highly focused interventions, which spare uninvolved areas that are often disrupted with drugs.
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pathological Basal Ganglia activity in movement disorders
Neuroscience, 2011Co-Authors: Thomas Wichmann, Jonathan O DostrovskyAbstract:Our understanding of the pathophysiology of movement disorders and associated changes in Basal Ganglia activities has significantly changed during the last few decades. This process began with the development of detailed anatomical models of the Basal Ganglia, followed by studies of Basal Ganglia activity patterns in animal models of common movement disorders and electrophysiological recordings in movement disorder patients undergoing functional neurosurgical procedures. These investigations first resulted in an appreciation of global activity changes in the Basal Ganglia in parkinsonism and other disorders, and later in the detailed description of pathological Basal Ganglia activity patterns, specifically burst patterns and oscillatory synchronous discharge of Basal Ganglia neurons. In this review, we critically summarize our current knowledge of the pathological discharge patterns of Basal Ganglia neurons in Parkinson's disease, dystonia, and dyskinesias.
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update on models of Basal Ganglia function and dysfunction
Parkinsonism & Related Disorders, 2009Co-Authors: Mahlon R Delong, Thomas WichmannAbstract:Circuit models of Basal Ganglia function and dysfunction have undergone significant changes over time. The previous view that the Basal Ganglia are centers in which massive convergence of cortical information occurred has now been replaced by a view in which these structures process information in a highly specific manner, participating in anatomical and functional modules that also involve cortex and thalamus. In addition, much has been learned about the intrinsic connections of the Basal Ganglia. While the Basal Ganglia-thalamocortical circuitry was originally seen almost exclusively in its relationship to the control of movement, these structures are now viewed as essential for higher level behavioral control, for instance in the regulation of habit learning or action selection. Probably the greatest benefit of these models has been that they have motivated a wealth of studies of the pathophysiology of movement disorders of Basal Ganglia origin, such as Parkinson's disease. Such studies, in turn, have helped to reshape the existing circuit models. In this paper we review these fascinating changes of our appreciation of the Basal Ganglia circuitry, and comment on the current state of our knowledge in this field.
Ann M. Graybiel - One of the best experts on this subject based on the ideXlab platform.
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Pathogenesis of dystonia: is it of cerebellar or Basal Ganglia origin?
Journal of Neurology Neurosurgery & Psychiatry, 2017Co-Authors: Ryuji Kaji, Kailash P. Bhatia, Ann M. GraybielAbstract:Dystonia is a disorder of motor programmes controlling semiautomatic movements or postures, with clinical features such as sensory trick , which suggests sensorimotor mismatch as the basis. Dystonia was originally classified as a Basal Ganglia disease. It is now regarded as a ‘ network’ disorder including the cerebellum, but the exact pathogenesis being unknown. Rare autopsy studies have found pathology both in the striatum and the cerebellum, and functional disorganisation was reported in the somatosensory cortex in patients. Recent animal studies showed physiologically tight di synaptic connections between the cerebellum and the striatum. We review clinical evidence in light of this new functional interaction between the cerebellum and Basal Ganglia, and put forward a hypothesis that dystonia is a Basal Ganglia disorder that can be induced by aberrant afferent inputs from the cerebellum.
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the Basal Ganglia learning new tricks and loving it
Current Opinion in Neurobiology, 2005Co-Authors: Ann M. GraybielAbstract:The field of Basal Ganglia research is exploding on every level — from discoveries at the molecular level to those based on human brain imaging. A remarkable series of new findings support the view that the Basal Ganglia are essential for some forms of learning-related plasticity. Other new findings are challenging some of the basic tenets of the field as it now stands. Combined with the new evidence on learning-related functions of the Basal Ganglia, these studies suggest that the Basal Ganglia are parts of a brain-wide set of adaptive neural systems promoting optimal motor and cognitive control.
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the Basal Ganglia and chunking of action repertoires
Neurobiology of Learning and Memory, 1998Co-Authors: Ann M. GraybielAbstract:The Basal Ganglia have been shown to contribute to habit and stimulus-response (S-R) learning. These forms of learning have the property of slow acquisition and, in humans, can occur without conscious awareness. This paper proposes that one aspect of Basal Ganglia-based learning is the recoding of cortically derived information within the striatum. Modular corticostriatal projection patterns, demonstrated experimentally, are viewed as producing recoded templates suitable for the gradual selection of new input-output relations in cortico-Basal Ganglia loops. Recordings from striatal projection neurons and interneurons show that activity patterns in the striatum are modified gradually during the course of S-R learning. It is proposed that this recoding within the striatum can chunk the representations of motor and cognitive action sequences so that they can be implemented as performance units. This scheme generalizes Miller's notion of information chunking to action control. The formation and the efficient implementation of action chunks are viewed as being based on predictive signals. It is suggested that information chunking provides a mechanism for the acquisition and the expression of action repertoires that, without such information compression would be biologically unwieldy or difficult to implement. The learning and memory functions of the Basal Ganglia are thus seen as core features of the Basal Ganglia's influence on motor and cognitive pattern generators.
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building action repertoires memory and learning functions of the Basal Ganglia
Current Opinion in Neurobiology, 1995Co-Authors: Ann M. GraybielAbstract:Research on the Basal Ganglia suggests that they are critically involved in building up sequences of behavior into meaningful, goal-directed repertoires. Work on rodents, monkeys and humans suggests that the Basal Ganglia act as part of a distributed forebrain system that helps to encode such repertoires through behavioral learning, and that is engaged in the expression of such repertoires once they have been internalized. The Basal Ganglia also may be critical to the expression of innate behavioral routines. Experimental findings on reward-based learning suggest that neural activity in the striatum and substantia nigra, pars compacta changes during behavioral learning. New evidence also suggests extreme specificity in the neural connections interrelating the Basal Ganglia, cerebral cortex and thalamus. Adaptive control of behavior may centrally depend on these circuits and the evaluator-reinforcement circuits that modulate them.
Peter L Strick - One of the best experts on this subject based on the ideXlab platform.
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the Basal Ganglia and the cerebellum nodes in an integrated network
Nature Reviews Neuroscience, 2018Co-Authors: Andreea C Bostan, Peter L StrickAbstract:The Basal Ganglia and the cerebellum are considered to be distinct subcortical systems that perform unique functional operations. The outputs of the Basal Ganglia and the cerebellum influence many of the same cortical areas but do so by projecting to distinct thalamic nuclei. As a consequence, the two subcortical systems were thought to be independent and to communicate only at the level of the cerebral cortex. Here, we review recent data showing that the Basal Ganglia and the cerebellum are interconnected at the subcortical level. The subthalamic nucleus in the Basal Ganglia is the source of a dense disynaptic projection to the cerebellar cortex. Similarly, the dentate nucleus in the cerebellum is the source of a dense disynaptic projection to the striatum. These observations lead to a new functional perspective that the Basal Ganglia, the cerebellum and the cerebral cortex form an integrated network. This network is topographically organized so that the motor, cognitive and affective territories of each node in the network are interconnected. This perspective explains how synaptic modifications or abnormal activity at one node can have network-wide effects. A future challenge is to define how the unique learning mechanisms at each network node interact to improve performance.
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functional anatomy of Basal Ganglia circuits with the cerebral cortex and the cerebellum
Progress in neurological surgery, 2018Co-Authors: Andreea C Bostan, Richard P Dum, Peter L StrickAbstract:The neural connections of the Basal Ganglia provide important insights into their function. Here, we discuss the current perspective on Basal Ganglia connections with the cerebral cortex and with the cerebellum. We review the evidence that the Basal Ganglia participate in functionally segregated circuits with motor and non-motor areas of the cerebral cortex. We then discuss the data that the Basal Ganglia are interconnected with the cerebellum. These results provide the anatomical substrate for Basal Ganglia contributions not only to the control of movement, but also to a variety of cognitive and affective functions. Furthermore, these findings indicate that abnormal activity in Basal Ganglia circuits with the cerebral cortex and with the cerebellum may contribute to both motor and non-motor deficits associated with several neurologic and psychiatric conditions.
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the Basal Ganglia communicate with the cerebellum
Proceedings of the National Academy of Sciences of the United States of America, 2010Co-Authors: Andreea C Bostan, Peter L StrickAbstract:The Basal Ganglia and cerebellum are major subcortical structures that influence not only movement, but putatively also cognition and affect. Both structures receive input from and send output to the cerebral cortex. Thus, the Basal Ganglia and cerebellum form multisynaptic loops with the cerebral cortex. Basal Ganglia and cerebellar loops have been assumed to be anatomically separate and to perform distinct functional operations. We investigated whether there is any direct route for Basal Ganglia output to influence cerebellar function that is independent of the cerebral cortex. We injected rabies virus (RV) into selected regions of the cerebellar cortex in cebus monkeys and used retrograde transneuronal transport of the virus to determine the origin of multisynaptic inputs to the injection sites. We found that the subthalamic nucleus of the Basal Ganglia has a substantial disynaptic projection to the cerebellar cortex. This pathway provides a means for both normal and abnormal signals from the Basal Ganglia to influence cerebellar function. We previously showed that the dentate nucleus of the cerebellum has a disynaptic projection to an input stage of Basal Ganglia processing, the striatum. Taken together these results provide the anatomical substrate for substantial two-way communication between the Basal Ganglia and cerebellum. Thus, the two subcortical structures may be linked together to form an integrated functional network.
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the cerebellum communicates with the Basal Ganglia
Nature Neuroscience, 2005Co-Authors: Leon Tremblay, Eiji Hoshi, Jean Feger, Peter L Carras, Peter L StrickAbstract:The cerebral cortex is interconnected with two major subcortical structures: the Basal Ganglia and the cerebellum. How and where cerebellar circuits interact with Basal Ganglia circuits has been a longstanding question. Using transneuronal transport of rabies virus in macaques, we found that a disynaptic pathway links an output stage of cerebellar processing, the dentate nucleus, with an input stage of Basal Ganglia processing, the striatum.
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Basal Ganglia and cerebellar loops motor and cognitive circuits
Brain Research Reviews, 2000Co-Authors: Frank A Middleton, Peter L StrickAbstract:The traditional view that the Basal Ganglia and cerebellum are simply involved in the control of movement has been challenged in recent years. One of the pivotal reasons for this reappraisal has been new information about Basal Ganglia and cerebellar connections with the cerebral cortex. In essence, recent anatomical studies have revealed that these connections are organized into discrete circuits or 'loops'. Rather than serving as a means for widespread cortical areas to gain access to the motor system, these loops reciprocally interconnect a large and diverse set of cerebral cortical areas with the Basal Ganglia and cerebellum. The properties of neurons within the Basal Ganglia or cerebellar components of these circuits resembles the properties of neurons within the cortical areas subserved by these loops. For example, neuronal activity within Basal Ganglia and cerebellar loops with motor areas of the cerebral cortex is highly correlated with parameters of movement, while neuronal activity within Basal Ganglia and cerebellar loops with areas of the prefrontal cortex is more related to aspects of cognitive function. Thus, individual loops appear to be involved in distinct behavioral functions. Studies of Basal Ganglia and cerebellar pathology support this conclusion. Damage to the Basal Ganglia or cerebellar components of circuits with motor areas of cortex leads to motor symptoms, whereas damage of the subcortical components of circuits with non-motor areas of cortex causes higher-order deficits. In this report, we review some of the new anatomical, physiological and behavioral findings that have contributed to a reappraisal of function concerning the Basal Ganglia and cerebellar loops with the cerebral cortex.
Anatol C Kreitzer - One of the best experts on this subject based on the ideXlab platform.
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cortico Basal Ganglia circuit function in psychiatric disease
Annual Review of Physiology, 2016Co-Authors: Lisa A Gunaydin, Anatol C KreitzerAbstract:Circuit dysfunction models of psychiatric disease posit that pathological behavior results from abnormal patterns of electrical activity in specific cells and circuits in the brain. Many psychiatric disorders are associated with abnormal activity in the prefrontal cortex and in the Basal Ganglia, a set of subcortical nuclei implicated in cognitive and motor control. Here we discuss the role of the Basal Ganglia and connected prefrontal regions in the etiology and treatment of obsessive-compulsive disorder, anxiety, and depression, emphasizing mechanistic work in rodent behavioral models to dissect causal cortico–Basal Ganglia circuits underlying discrete behavioral symptom domains relevant to these complex disorders.
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control of Basal Ganglia output by direct and indirect pathway projection neurons
The Journal of Neuroscience, 2013Co-Authors: Benjamin S Freeze, Alexxai V Kravitz, Nora Hammack, Joshua D Berke, Anatol C KreitzerAbstract:The direct and indirect efferent pathways from striatum ultimately reconverge to influence Basal Ganglia output nuclei, which in turn regulate behavior via thalamocortical and brainstem motor circuits. However, the distinct contributions of these two efferent pathways in shaping Basal Ganglia output are not well understood. We investigated these processes using selective optogenetic control of the direct and indirect pathways, in combination with single-unit recording in the Basal Ganglia output nucleus substantia nigra pars reticulata (SNr) in mice. Optogenetic activation of striatal direct and indirect pathway projection neurons produced diverse cellular responses in SNr neurons, with stimulation of each pathway eliciting both excitations and inhibitions. Despite this response heterogeneity, the effectiveness of direct pathway stimulation in producing movement initiation correlated selectively with the subpopulation of inhibited SNr neurons. In contrast, effective indirect pathway-mediated motor suppression was most strongly influenced by excited SNr neurons. Our results support the theory that key Basal Ganglia output neurons serve as an inhibitory gate over motor output that can be opened or closed by striatal direct and indirect pathways, respectively.
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striatal plasticity and Basal Ganglia circuit function
Neuron, 2008Co-Authors: Anatol C Kreitzer, Robert C MalenkaAbstract:The dorsal striatum, which consists of the caudate and putamen, is the gateway to the Basal Ganglia. It receives convergent excitatory afferents from cortex and thalamus and forms the origin of the direct and indirect pathways, which are distinct Basal Ganglia circuits involved in motor control. It is also a major site of activity-dependent synaptic plasticity. Striatal plasticity alters the transfer of information throughout Basal Ganglia circuits and may represent a key neural substrate for adaptive motor control and procedural memory. Here, we review current understanding of synaptic plasticity in the striatum and its role in the physiology and pathophysiology of Basal Ganglia function.
Jose A Obeso - One of the best experts on this subject based on the ideXlab platform.
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functional neuroanatomy of the Basal Ganglia
Cold Spring Harbor Perspectives in Medicine, 2012Co-Authors: Jose L Lanciego, Natasha Luquin, Jose A ObesoAbstract:The “Basal Ganglia” refers to a group of subcortical nuclei responsible primarily for motor control, as well as other roles such as motor learning, executive functions and behaviors, and emotions. Proposed more than two decades ago, the classical Basal Ganglia model shows how information flows through the Basal Ganglia back to the cortex through two pathways with opposing effects for the proper execution of movement. Although much of the model has remained, the model has been modified and amplified with the emergence of new data. Furthermore, parallel circuits subserve the other functions of the Basal Ganglia engaging associative and limbic territories. Disruption of the Basal Ganglia network forms the basis for several movement disorders. This article provides a comprehensive account of Basal Ganglia functional anatomy and chemistry and the major pathophysiological changes underlying disorders of movement. We try to answer three key questions related to the Basal Ganglia, as follows: What are the Basal Ganglia? What are they made of? How do they work? Some insight on the canonical Basal Ganglia model is provided, together with a selection of paradoxes and some views over the horizon in the field.
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pathophysiology of the Basal Ganglia in parkinson s disease
Trends in Neurosciences, 2000Co-Authors: Jose A Obeso, Jose L Lanciego, Manuel Rodriguez, Maria C Rodriguezoroz, J Artieda, Nancy Gonzalo, Warren C OlanowAbstract:Insight into the organization of the Basal Ganglia in the normal, parkinsonian and L-dopa-induced dyskinesia states is critical for the development of newer and more effective therapies for Parkinson's disease. We believe that the Basal Ganglia can no longer be thought of as a unidirectional linear system that transfers information based solely on a firing-rate code. Rather, we propose that the Basal Ganglia is a highly organized network, with operational characteristics that simulate a non-linear dynamic system.
