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Nature Reviews. Neuroscience Jun 2018The basal ganglia and the cerebellum are considered to be distinct subcortical systems that perform unique functional operations. The outputs of the basal ganglia and... (Review)
Review
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.
Topics: Animals; Basal Ganglia; Cerebellum; Humans; Models, Neurological; Motivation; Nervous System Diseases; Neural Pathways; Reward; Subthalamic Nucleus; Thalamus
PubMed: 29643480
DOI: 10.1038/s41583-018-0002-7 -
Nature Oct 2021The cortico-basal ganglia-thalamo-cortical loop is one of the fundamental network motifs in the brain. Revealing its structural and functional organization is critical...
The cortico-basal ganglia-thalamo-cortical loop is one of the fundamental network motifs in the brain. Revealing its structural and functional organization is critical to understanding cognition, sensorimotor behaviour, and the natural history of many neurological and neuropsychiatric disorders. Classically, this network is conceptualized to contain three information channels: motor, limbic and associative. Yet this three-channel view cannot explain the myriad functions of the basal ganglia. We previously subdivided the dorsal striatum into 29 functional domains on the basis of the topography of inputs from the entire cortex. Here we map the multi-synaptic output pathways of these striatal domains through the globus pallidus external part (GPe), substantia nigra reticular part (SNr), thalamic nuclei and cortex. Accordingly, we identify 14 SNr and 36 GPe domains and a direct cortico-SNr projection. The striatonigral direct pathway displays a greater convergence of striatal inputs than the more parallel striatopallidal indirect pathway, although direct and indirect pathways originating from the same striatal domain ultimately converge onto the same postsynaptic SNr neurons. Following the SNr outputs, we delineate six domains in the parafascicular and ventromedial thalamic nuclei. Subsequently, we identify six parallel cortico-basal ganglia-thalamic subnetworks that sequentially transduce specific subsets of cortical information through every elemental node of the cortico-basal ganglia-thalamic loop. Thalamic domains relay this output back to the originating corticostriatal neurons of each subnetwork in a bona fide closed loop.
Topics: Animals; Basal Ganglia; Cerebral Cortex; Male; Mice; Mice, Inbred C57BL; Neural Pathways; Neurons; Thalamus
PubMed: 34616074
DOI: 10.1038/s41586-021-03993-3 -
Seminars in Pediatric Neurology Apr 2018Movement disorders typically arise from dysfunction of the basal ganglia (BG), cerebellum, or both. The BG-a group of deep, subcortical structures-form complex circuits... (Review)
Review
Movement disorders typically arise from dysfunction of the basal ganglia (BG), cerebellum, or both. The BG-a group of deep, subcortical structures-form complex circuits that shape motor control and motor learning, as well as limbic and associative functions. In this article, we summarize the anatomy and physiology of the BG and cerebellum, and briefly highlight the clinical syndromes that may arise in the context of their injury or dysfunction.
Topics: Animals; Basal Ganglia; Humans; Movement Disorders; Neural Pathways; Syndrome
PubMed: 29735113
DOI: 10.1016/j.spen.2017.12.005 -
The Lancet. Child & Adolescent Health Dec 2019The diagnosis and management of movement disorders in children can be improved by understanding the pathways, neurons, ion channels, and receptors involved in motor... (Review)
Review
The diagnosis and management of movement disorders in children can be improved by understanding the pathways, neurons, ion channels, and receptors involved in motor learning and control. In this Review, we use a localisation approach to examine the anatomy, physiology, and circuitry of the basal ganglia and highlight the mechanisms that underlie some of the major movement disorders in children. We review the connections between the basal ganglia and the thalamus and cortex, address the basic clinical definitions of movement disorders, and then place diseases within an anatomical or physiological framework that highlights basal ganglia function. We discuss how new pharmacological, behavioural, and electrophysiological approaches might benefit children with movement disorders by modifying synaptic function. A better understanding of the mechanisms underlying movement disorders allows improved diagnostic and treatment decisions.
Topics: Adolescent; Basal Ganglia; Cerebral Cortex; Child; Cognitive Behavioral Therapy; Dopamine; Electrophysiological Phenomena; Humans; Motor Neurons; Movement Disorders; Synapses; Thalamus; Young Adult
PubMed: 31653548
DOI: 10.1016/S2352-4642(19)30330-X -
Arquivos de Neuro-psiquiatria Dec 2020
Topics: Basal Ganglia; Basal Ganglia Diseases; Humans; Parkinsonian Disorders
PubMed: 33263640
DOI: 10.1590/0004-282X20200103 -
Neuropharmacology Aug 2017Brain circuits that include the cortex and basal ganglia make up the bulk of the forebrain, and influence behaviors related to almost all aspects of affective, cognitive... (Review)
Review
Brain circuits that include the cortex and basal ganglia make up the bulk of the forebrain, and influence behaviors related to almost all aspects of affective, cognitive and sensorimotor functions. The learning of new actions as well as association of existing action repertoires with environmental events are key functions of this circuitry. Unfortunately, the cortico-basal ganglia circuitry is also the target for all drugs of abuse, including alcohol. This makes the circuitry susceptible to the actions of chronic alcohol exposure that impairs circuit function in ways that contribute to cognitive dysfunction and drug use disorders. In the present review, we describe the connectivity and functions of the associative, limbic and sensorimotor cortico-basal ganglia circuits. We then review the effects of acute and chronic alcohol exposure on circuit function. Finally, we review studies examining the roles of the different circuits and circuit elements in alcohol use and abuse. We attempt to synthesize information from a variety of studies in laboratory animals and humans to generate hypotheses about how the three circuits interact with each other and with the other brain circuits during exposure to alcohol and during the development of alcohol use disorders. This article is part of the Special Issue entitled "Alcoholism".
Topics: Alcohol Drinking; Alcoholism; Animals; Basal Ganglia; Cerebral Cortex; Ethanol; Learning; Limbic System; Models, Animal; Neural Pathways; Neurons
PubMed: 28341206
DOI: 10.1016/j.neuropharm.2017.03.023 -
The Neuroscientist : a Review Journal... Jun 2017The basal ganglia (BG) are the major subcortical nuclei in the brain. Disorders implicating the BG are characterized by diverse symptoms, but it remains unclear what... (Review)
Review
The basal ganglia (BG) are the major subcortical nuclei in the brain. Disorders implicating the BG are characterized by diverse symptoms, but it remains unclear what these symptoms have in common or how they can be explained by changes in the BG circuits. This review summarizes recent findings that not only question traditional assumptions about the role of the BG in movement but also elucidate general computations performed by these circuits. To explain these findings, a new conceptual framework is introduced for understanding the role of the BG in behavior. According to this framework, the cortico-BG networks implement transition control in an extended hierarchy of closed loop negative feedback control systems. The transition control model provides a solution to the posture/movement problem, by postulating that BG outputs send descending signals to alter the reference states of downstream position control systems for orientation and body configuration. It also explains major neurological symptoms associated with BG pathology as a result of changes in system parameters such as multiplicative gain and damping.
Topics: Animals; Basal Ganglia; Humans; Models, Neurological; Movement; Neural Pathways
PubMed: 27306757
DOI: 10.1177/1073858416654115 -
Proceedings of the Japan Academy.... 2018Involuntary movements and parkinsonism have been interesting and important topics in neurology since the last century. The development of anatomical and physiological... (Review)
Review
Involuntary movements and parkinsonism have been interesting and important topics in neurology since the last century. The development of anatomical and physiological studies of the neural circuitry of motor systems has encouraged the study of movement disorders by means of pathophysiology and brain imaging.Multichannel electromyography from affected muscles has generated objective and analytical data on chorea, ballism, athetosis, and dystonia. Studies using floor reaction forces revealed the pathophysiology of freezing of gait in parkinsonism. Akinesia and bradykinesia are attributable to dysfunctions in the basal ganglia, frontal lobe, and parieto-occipital visual association cortex.Reciprocal innervation is an essential mechanism of smooth voluntary movement. Spinal reflexes on reciprocal innervation has been investigated in awake humans, and the pathophysiology of spasticity and Parkinson's disease were revealed as a result. Clinical applications for the treatment and evaluation of status have been developed.For future studies, detailed neural mechanisms underlying the development of motor disorders in basal ganglia diseases and recovery by interventions including surgery and neurorehabilitation are important.
Topics: Basal Ganglia; Humans; Movement Disorders; Posture
PubMed: 30078828
DOI: 10.2183/pjab.94.019 -
Medicina (Kaunas, Lithuania) May 2023Perivascular spaces (PVS) and their enlargement (EPVS) have been gaining interest as EPVS can be visualized non-invasively by magnetic resonance imaging (MRI) when... (Review)
Review
Perivascular spaces (PVS) and their enlargement (EPVS) have been gaining interest as EPVS can be visualized non-invasively by magnetic resonance imaging (MRI) when viewing T-2-weighted images. EPVS are most commonly observed in the regions of the basal ganglia and the centrum semiovale; however, they have also been identified in the frontal cortex and hippocampal regions. EPVS are known to be increased in aging and hypertension, and are considered to be a biomarker of cerebral small vessel disease (SVD). Interest in EPVS has been significantly increased because these PVS are now considered to be an essential conduit necessary for the glymphatic pathway to provide the necessary efflux of metabolic waste. Metabolic waste includes misfolded proteins of amyloid beta and tau that are known to accumulate in late-onset Alzheimer's disease (LOAD) within the interstitial fluid that is delivered to the subarachnoid space and eventually the cerebral spinal fluid (CSF). The CSF acts as a sink for accumulating neurotoxicities and allows clinical screening to potentially detect if LOAD may be developing early on in its clinical progression via spinal fluid examination. EPVS are thought to occur by obstruction of the PVS that associates with excessive neuroinflammation, oxidative stress, and vascular stiffening that impairs flow due to a dampening of the arterial and arteriolar pulsatility that aids in the convective flow of the metabolic debris within the glymphatic effluxing system. Additionally, increased EPVS has also been associated with Parkinson's disease and non-age-related multiple sclerosis (MS).
Topics: Humans; Amyloid beta-Peptides; Magnetic Resonance Imaging; Aging; Basal Ganglia; Arteries
PubMed: 37241149
DOI: 10.3390/medicina59050917 -
Social Cognitive and Affective... Jul 2020The basal ganglia (BG) and the cerebellum historically have been relegated to a functional role in producing or modulating motor output. Recent research, however, has... (Review)
Review
The basal ganglia (BG) and the cerebellum historically have been relegated to a functional role in producing or modulating motor output. Recent research, however, has emphasized the importance of these subcortical structures in multiple functional domains, including affective processes such as emotion recognition, subjective feeling elicitation and reward valuation. The pathways through the thalamus that connect the BG and cerebellum directly to each other and with extensive regions of the cortex provide a structural basis for their combined influence on limbic function. By regulating cortical oscillations to guide learning and strengthening rewarded behaviors or thought patterns to achieve a desired goal state, these regions can shape the way an individual processes emotional stimuli. This review will discuss the basic structure and function of the BG and cerebellum and propose an updated view of their functional role in human affective processing.
Topics: Basal Ganglia; Cerebellum; Emotions; Humans; Learning; Motivation; Neural Pathways; Neuroimaging
PubMed: 32507876
DOI: 10.1093/scan/nsaa076