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The FEBS Journal Apr 2022The synaptic pathways in the striatum are central to basal ganglia functions including motor control, learning and organization, action selection, acquisition of motor... (Review)
Review
The synaptic pathways in the striatum are central to basal ganglia functions including motor control, learning and organization, action selection, acquisition of motor skills, cognitive function, and emotion. Here, we review the role of the striatum and its connections in motor learning and performance. The development of new techniques to record neuronal activity and animal models of motor disorders using neurotoxin, pharmacological, and genetic manipulations are revealing pathways that underlie motor performance and motor learning, as well as how they are altered by pathophysiological mechanisms. We discuss approaches that can be used to analyze complex motor skills, particularly in rodents, and identify specific questions central to understanding how striatal circuits mediate motor learning.
Topics: Animals; Basal Ganglia; Corpus Striatum
PubMed: 33977645
DOI: 10.1111/febs.15908 -
Annual Review of Neuroscience 2014The basal ganglia are a series of interconnected subcortical nuclei. The function and dysfunction of these nuclei have been studied intensively in motor control, but... (Review)
Review
The basal ganglia are a series of interconnected subcortical nuclei. The function and dysfunction of these nuclei have been studied intensively in motor control, but more recently our knowledge of these functions has broadened to include prominent roles in cognition and affective control. This review summarizes historical models of basal ganglia function, as well as findings supporting or conflicting with these models, while emphasizing recent work in animals and humans directly testing the hypotheses generated by these models.
Topics: Animals; Basal Ganglia; Basal Ganglia Diseases; Humans; Models, Neurological; Neural Pathways
PubMed: 25032493
DOI: 10.1146/annurev-neuro-071013-013916 -
Brain Structure & Function Jan 2017Basal ganglia and the cerebellum are part of a densely interconnected network. While both subcortical structures process information in basically segregated loops that...
Basal ganglia and the cerebellum are part of a densely interconnected network. While both subcortical structures process information in basically segregated loops that primarily interact in the neocortex, direct subcortical interaction has been recently confirmed by neuroanatomical studies using viral transneuronal tracers in non-human primate brains. The thalamus is thought to be the main relay station of both projection systems. Yet, our understanding of subcortical basal ganglia and cerebellar interconnectivity within the human thalamus is rather sparse, primarily due to limitation in the acquisition of in vivo tracing. Consequently, we strive to characterize projections of both systems and their potential overlap within the human thalamus by diffusion MRI and tractography. Our analysis revealed a decreasing anterior-to-posterior gradient for pallido-thalamic connections in: (1) the ventral-anterior thalamus, (2) the intralaminar nuclei, and (3) midline regions. Conversely, we found a decreasing posterior-to-anterior gradient for dentato-thalamic projections predominantly in: (1) the ventral-lateral and posterior nucleus; (2) dorsal parts of the intralaminar nuclei and the subparafascicular nucleus, and (3) the medioventral and lateral mediodorsal nucleus. A considerable overlap of connectivity pattern was apparent in intralaminar nuclei and midline regions. Notably, pallidal and cerebellar projections were both hemispherically lateralized to the left thalamus. While strikingly consistent with findings from transneuronal studies in non-human primates as well as with pre-existing anatomical studies on developmentally expressed markers or pathological human brains, our assessment provides distinctive connectional fingerprints that illustrate the anatomical substrate of integrated functional networks between basal ganglia and the cerebellum. Thereby, our findings furnish useful implications for cerebellar contributions to the clinical symptomatology of movement disorders.
Topics: Adult; Basal Ganglia; Cerebellum; Diffusion Magnetic Resonance Imaging; Female; Globus Pallidus; Humans; Male; Neural Pathways; Thalamus; Young Adult
PubMed: 27089884
DOI: 10.1007/s00429-016-1223-z -
European Journal of Paediatric... Mar 2018Basal ganglia circuits are organized to selected desired actions and to inhibit potentially competing unwanted actions. This is accomplished through a complex circuitry... (Review)
Review
Basal ganglia circuits are organized to selected desired actions and to inhibit potentially competing unwanted actions. This is accomplished through a complex circuitry that is modified through development and learning. Mechanisms of neural plasticity underlying these modifications are increasingly understood, but new mechanisms continue to be discovered. Dystonia, a movement disorder characterized by involuntary muscle contractions that cause abnormal postures and movements. Emerging evidence points to important links between mechanisms of plasticity and the manifestations of dystonia. Investigation of these mechanisms has improved understanding of the action of currently used medication and is informing the development of new treatments.
Topics: Basal Ganglia; Dystonia; Humans; Neuronal Plasticity
PubMed: 29396175
DOI: 10.1016/j.ejpn.2018.01.005 -
The European Journal of Neuroscience May 2016The external globus pallidus (GPe) of the basal ganglia is in a unique and powerful position to influence processing of motor information by virtue of its widespread... (Review)
Review
The external globus pallidus (GPe) of the basal ganglia is in a unique and powerful position to influence processing of motor information by virtue of its widespread projections to all basal ganglia nuclei. Despite the clinical importance of the GPe in common motor disorders such as Parkinson's disease, there is only limited information about its cellular composition and organizational principles. In this review, recent advances in the understanding of the diversity in the molecular profile, anatomy, physiology and corresponding behaviour during movement of GPe neurons are described. Importantly, this study attempts to build consensus and highlight commonalities of the cellular classification based on existing but contentious literature. Additionally, an analysis of the literature concerning the intricate reciprocal loops formed between the GPe and major synaptic partners, including both the striatum and the subthalamic nucleus, is provided. In conclusion, the GPe has emerged as a crucial node in the basal ganglia macrocircuit. While subtleties in the cellular makeup and synaptic connection of the GPe create new challenges, modern research tools have shown promise in untangling such complexity, and will provide better understanding of the roles of the GPe in encoding movements and their associated pathologies.
Topics: Animals; Basal Ganglia; Brain Diseases; Globus Pallidus; Humans; Movement; Neural Pathways; Neurons; Subthalamic Nucleus
PubMed: 26841063
DOI: 10.1111/ejn.13196 -
Current Opinion in Neurobiology Aug 2015Many behaviors necessary for organism survival are learned anew and become organized as complex sequences of actions. Recent studies suggest that cortico-basal ganglia... (Review)
Review
Many behaviors necessary for organism survival are learned anew and become organized as complex sequences of actions. Recent studies suggest that cortico-basal ganglia circuits are important for chunking isolated movements into precise and robust action sequences that permit the achievement of particular goals. During sequence learning many neurons in the basal ganglia develop sequence-related activity-related to the initiation, execution, and termination of sequences-suggesting that action sequences are processed as action units. Corticostriatal plasticity is critical for the crystallization of action sequences, and for the development of sequence-related neural activity. Furthermore, this sequence-related activity is differentially expressed in direct and indirect basal ganglia pathways. These findings have implications for understanding the symptoms associated with movement and psychiatric disorders.
Topics: Animals; Basal Ganglia; Humans; Models, Neurological; Movement; Nerve Net
PubMed: 26189204
DOI: 10.1016/j.conb.2015.06.011 -
Neuroradiology Jul 2021Incidental basal ganglia calcifications are a common finding on computed tomography (CT). We investigated the histological characteristics of these calcifications and...
Incidental basal ganglia calcifications are a common finding on computed tomography (CT). We investigated the histological characteristics of these calcifications and their association with CT findings, using post-mortem basal ganglia tissue from 22 patients. Eight patients had basal ganglia calcifications on histology, and six patients had calcifications on CT, varying from mild to severe. Four patients had calcifications identified by both histology and CT, and two patients had calcifications detected by CT but not by histology, possibly because of insufficient tissue available. Calcifications were found mainly in the tunica media of arterioles located in the globus pallidus, which suggests that incidental CT calcifications are vascular in nature. However, tunica media calcifications, and thereby incidental basal ganglia calcifications, are probably not related to atherosclerosis.
Topics: Basal Ganglia; Basal Ganglia Diseases; Calcinosis; Globus Pallidus; Humans; Tomography, X-Ray Computed
PubMed: 33745004
DOI: 10.1007/s00234-021-02680-4 -
Journal of Neurophysiology Apr 2016Viral vectors were originally developed to deliver genes into host cells for therapeutic potential. However, viral vector use in neuroscience research has increased... (Review)
Review
Viral vectors were originally developed to deliver genes into host cells for therapeutic potential. However, viral vector use in neuroscience research has increased because they enhance interpretation of the anatomy and physiology of brain circuits compared with conventional tract tracing or electrical stimulation techniques. Viral vectors enable neuronal or glial subpopulations to be labeled or stimulated, which can be spatially restricted to a single target nucleus or pathway. Here we review the use of viral vectors to examine the structure and function of motor and limbic basal ganglia (BG) networks in normal and pathological states. We outline the use of viral vectors, particularly lentivirus and adeno-associated virus, in circuit tracing, optogenetic stimulation, and designer drug stimulation experiments. Key studies that have used viral vectors to trace and image pathways and connectivity at gross or ultrastructural levels are reviewed. We explain how optogenetic stimulation and designer drugs used to modulate a distinct pathway and neuronal subpopulation have enhanced our mechanistic understanding of BG function in health and pathophysiology in disease. Finally, we outline how viral vector technology may be applied to neurological and psychiatric conditions to offer new treatments with enhanced outcomes for patients.
Topics: Animals; Basal Ganglia; Dependovirus; Genetic Vectors; Humans; Lentivirus; Neuroimaging; Neurons; Optogenetics
PubMed: 26888111
DOI: 10.1152/jn.01131.2015 -
Brain and Cognition Mar 2000The traditional view that the basal ganglia are simply involved in the control of movement has been challenged in recent years. Three lines of evidence indicate that the... (Review)
Review
The traditional view that the basal ganglia are simply involved in the control of movement has been challenged in recent years. Three lines of evidence indicate that the basal ganglia also are involved in nonmotor operations. First, the results of anatomical studies clearly indicate that the basal ganglia participate in multiple circuits or 'loops' with cognitive areas of the cerebral cortex. Second, the activity of neurons within selected portions of the basal ganglia is more related to cognitive or sensory operations than to motor functions. Finally, in some instances basal ganglia lesions cause primarily cognitive or sensory disturbances without gross motor impairments. In this report, we briefly review some of these data and present a new anatomical framework for understanding the basal ganglia contributions to nonmotor function.
Topics: Basal Ganglia; Cognition; Humans; Movement; Neural Pathways
PubMed: 10744919
DOI: 10.1006/brcg.1999.1099 -
Scientific Reports Nov 2021Recent studies have shown that temporal stability of the neuronal activity over time can be estimated by the structure of the spike-count autocorrelation of neuronal...
Recent studies have shown that temporal stability of the neuronal activity over time can be estimated by the structure of the spike-count autocorrelation of neuronal populations. This estimation, called the intrinsic timescale, has been computed for several cortical areas and can be used to propose a cortical hierarchy reflecting a scale of temporal receptive windows between areas. In this study, we performed an autocorrelation analysis on neuronal populations of three basal ganglia (BG) nuclei, including the striatum and the subthalamic nucleus (STN), the input structures of the BG, and the external globus pallidus (GPe). The analysis was performed during the baseline period of a motivational visuomotor task in which monkeys had to apply different amounts of force to receive different amounts of reward. We found that the striatum and the STN have longer intrinsic timescales than the GPe. Moreover, our results allow for the placement of these subcortical structures within the already-defined scale of cortical temporal receptive windows. Estimates of intrinsic timescales are important in adding further constraints in the development of computational models of the complex dynamics among these nuclei and throughout cortico-BG-thalamo-cortical loops.
Topics: Animals; Basal Ganglia; Cognition; Corpus Striatum; Globus Pallidus; Macaca mulatta; Male; Nerve Net; Subthalamic Nucleus; Time Factors
PubMed: 34725371
DOI: 10.1038/s41598-021-00512-2