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Trends in Neurosciences Oct 1989Basal ganglia disorders are a heterogeneous group of clinical syndromes with a common anatomic locus within the basal ganglia. To account for the variety of clinical... (Review)
Review
Basal ganglia disorders are a heterogeneous group of clinical syndromes with a common anatomic locus within the basal ganglia. To account for the variety of clinical manifestations associated with insults to various parts of the basal ganglia we propose a model in which specific types of basal ganglia disorders are associated with changes in the function of subpopulations of striatal projection neurons. This model is based on a synthesis of experimental animal and post-mortem human anatomic and neurochemical data. Hyperkinetic disorders, which are characterized by an excess of abnormal movements, are postulated to result from the selective impairment of striatal neurons projecting to the lateral globus pallidus. Hypokinetic disorders, such as Parkinson's disease, are hypothesized to result from a complex series of changes in the activity of striatal projection neuron subpopulations resulting in an increase in basal ganglia output. This model suggests that the activity of subpopulations of striatal projection neurons is differentially regulated by striatal afferents and that different striatal projection neuron subpopulations may mediate different aspects of motor control.
Topics: Basal Ganglia; Basal Ganglia Diseases; Humans; Movement Disorders
PubMed: 2479133
DOI: 10.1016/0166-2236(89)90074-x -
Neuron Nov 2008The 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... (Review)
Review
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.
Topics: Animals; Basal Ganglia; Basal Ganglia Diseases; Cerebral Cortex; Humans; Memory; Movement; Neostriatum; Neural Pathways; Neuronal Plasticity; Synaptic Transmission; Thalamus
PubMed: 19038213
DOI: 10.1016/j.neuron.2008.11.005 -
Nature Neuroscience Aug 2014The basal ganglia are subcortical nuclei controlling voluntary actions and have been implicated in Parkinson's disease (PD). The prevailing model of basal ganglia... (Review)
Review
The basal ganglia are subcortical nuclei controlling voluntary actions and have been implicated in Parkinson's disease (PD). The prevailing model of basal ganglia function states that two circuits, the direct and indirect pathways, originate from distinct populations of striatal medium spiny neurons (MSNs) and project to different output structures. These circuits are believed to have opposite effects on movement. Specifically, the activity of direct pathway MSNs is postulated to promote movement, whereas the activation of indirect pathway MSNs is hypothesized to inhibit it. Recent findings have revealed that this model might not fully account for the concurrent activation of both pathways during movement. Accordingly, we propose a model in which intrastriatal connections are critical and the two pathways are structurally and functionally intertwined. Thus, all MSNs might either facilitate or inhibit movement depending on the form of synaptic plasticity expressed at a certain moment. In PD, alterations of dopamine-dependent synaptic plasticity could alter this coordinated activity.
Topics: Animals; Basal Ganglia; Humans; Models, Neurological; Movement; Neural Pathways; Neurons
PubMed: 25065439
DOI: 10.1038/nn.3743 -
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 -
European Journal of Paediatric... Mar 2018Basal ganglia are subcortical structures specialized at very early age, functionally different according to the right or left side. They are part of complex distributed... (Review)
Review
Basal ganglia are subcortical structures specialized at very early age, functionally different according to the right or left side. They are part of complex distributed network composed by parallel segregated loops where specific information are processed and open loops where different information are integrated. These loops are connected to specialized cortical areas thus entering into distributed processing of higher order cognitive functions and behaviours. Lesion or malfunction of basal ganglia nuclei cause deficits in different neuropsychological functions and neurobehavioural diseases, such Autism Spectrum Disorder, Attention Deficit/Hyperactivity Disorder, Tourette syndrome, etc., for the reciprocal connections from and to the limbic system and the frontal system. Basal ganglia have a computational functioning, working by activation and inhibition sequences, coded in time and space and regulated by inhibitory and excitatory mechanisms, with such accuracy to guarantee an effective and elegant product.
Topics: Basal Ganglia; Cognition; Humans; Nervous System Diseases
PubMed: 29396173
DOI: 10.1016/j.ejpn.2018.01.009 -
Neuroimaging Clinics of North America Aug 2022Conventional MR imaging does not discriminate basal ganglia and thalamic internal anatomy well. Radiology reports describe anatomic locations but not specific functional... (Review)
Review
Conventional MR imaging does not discriminate basal ganglia and thalamic internal anatomy well. Radiology reports describe anatomic locations but not specific functional structures. Functional neurosurgery uses indirect targeting based on commissural coordinates or atlases that do not fully account for individual variability. We describe innovative MR imaging sequences that improve the visualization of normal anatomy in this complex brain region and may increase our understanding of basal ganglia and thalamic function. Better visualization also may improve treatments for movement disorders and other emerging functional neurosurgery targets. We aim to provide an accessible review of the most clinically-relevant neuroanatomy within the thalamus and basal ganglia.
Topics: Basal Ganglia; Brain; Humans; Magnetic Resonance Imaging; Neurosurgical Procedures; Thalamus
PubMed: 35843660
DOI: 10.1016/j.nic.2022.05.003 -
Trends in Neurosciences Feb 1995
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Reviews of Oculomotor Research 1989
Review
Topics: Animals; Basal Ganglia; Caudate Nucleus; Humans; Ocular Motility Disorders; Saccades; Substantia Nigra; Superior Colliculi
PubMed: 2486325
DOI: No ID Found -
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 -
European Journal of Radiology May 2013The term "basal ganglia" refers to caudate and lentiform nuclei, the latter composed of putamen and globus pallidus, substantia nigra and subthalamic nuclei and these... (Review)
Review
The term "basal ganglia" refers to caudate and lentiform nuclei, the latter composed of putamen and globus pallidus, substantia nigra and subthalamic nuclei and these deep gray matter structures belong to the extrapyramidal system. Many diseases may present as basal ganglia abnormalities. Magnetic resonance imaging (MRI) and computed tomography (CT) - to a lesser degree - allow for detection of basal ganglia injury. In many cases, MRI alone does not usually allow to establish diagnosis but together with the knowledge of age and circumstances of onset and clinical course of the disease is a powerful tool of differential diagnosis. The lesions may be unilateral: in Rassmussen encephalitis, diabetes with hemichorea/hemiballism and infarction or - more frequently - bilateral in many pathologic conditions. Restricted diffusion is attributable to infarction, acute hypoxic-ischemic injury, hypoglycemia, Leigh disease, encephalitis and CJD. Contrast enhancement may be seen in cases of infarction and encephalitis. T1-hyperintensity of the lesions is uncommon and may be observed unilaterally in case of hemichorea/hemiballism and bilaterally in acute asphyxia in term newborns, in hypoglycemia, NF1, Fahr disease and manganese intoxication. Decreased signal intensity on GRE/T2*-weighted images and/or SWI indicating iron, calcium or hemosiderin depositions is observed in panthotenate kinase-associated neurodegeneration, Parkinson variant of multiple system atrophy, Fahr disease (and other calcifications) as well as with the advancing age. There are a few papers in the literature reviewing basal ganglia lesions. The authors present a more detailed review with rich iconography from the own archive.
Topics: Basal Ganglia; Basal Ganglia Diseases; Humans; Magnetic Resonance Imaging; Tomography, X-Ray Computed
PubMed: 23313708
DOI: 10.1016/j.ejrad.2012.12.006