-
Movement Disorders : Official Journal... Sep 2018
Topics: Basal Ganglia; Humans; Parkinson Disease
PubMed: 30311976
DOI: 10.1002/mds.27483 -
Frontiers in Neural Circuits 2015When Hubel (1982) referred to layer 1 of primary visual cortex as "… a 'crowning mystery' to keep area-17 physiologists busy for years to come …" he could have been... (Review)
Review
When Hubel (1982) referred to layer 1 of primary visual cortex as "… a 'crowning mystery' to keep area-17 physiologists busy for years to come …" he could have been talking about any cortical area. In the 80's and 90's there were no methods to examine this neuropile on the surface of the cortex: a tangled web of axons and dendrites from a variety of different places with unknown specificities and doubtful connections to the cortical output neurons some hundreds of microns below. Recently, three changes have made the crowning enigma less of an impossible mission: the clear presence of neurons in layer 1 (L1), the active conduction of voltage along apical dendrites and optogenetic methods that might allow us to look at one source of input at a time. For all of those reasons alone, it seems it is time to take seriously the function of L1. The functional properties of this layer will need to wait for more experiments but already L1 cells are GAD67 positive, i.e., inhibitory! They could reverse the sign of the thalamic glutamate (GLU) input for the entire cortex. It is at least possible that in the near future normal activity of individual sources of L1 could be detected using genetic tools. We are at the outset of important times in the exploration of thalamic functions and perhaps the solution to the crowning enigma is within sight. Our review looks forward to that solution from the solid basis of the anatomy of the basal ganglia output to motor thalamus. We will focus on L1, its afferents, intrinsic neurons and its influence on responses of pyramidal neurons in layers 2/3 and 5. Since L1 is present in the whole cortex we will provide a general overview considering evidence mainly from the somatosensory (S1) cortex before focusing on motor cortex.
Topics: Animals; Basal Ganglia; Motor Cortex; Thalamus
PubMed: 26582979
DOI: 10.3389/fncir.2015.00071 -
Dialogues in Clinical Neuroscience Mar 2016Many studies have suggested that the striatum, located at the interface of the cortico-basal ganglia-thalamic circuit, consists of separate circuits that serve distinct...
Many studies have suggested that the striatum, located at the interface of the cortico-basal ganglia-thalamic circuit, consists of separate circuits that serve distinct functions It plays an important role in motor planning, value processing, and decision making.
Topics: Basal Ganglia; Decision Making; Dopamine; Humans; Reward
PubMed: 27069375
DOI: 10.31887/DCNS.2016.18.1/fthibaut -
Appetite Jan 2020Reward-centred models have proposed that anomalies in the basal ganglia circuitry that underlies reward learning and habit formation perpetuate anorexia nervosa (AN)....
BACKGROUND
Reward-centred models have proposed that anomalies in the basal ganglia circuitry that underlies reward learning and habit formation perpetuate anorexia nervosa (AN). The present study aimed to investigate the volume and shape of key basal ganglia regions, including the bilateral caudate, putamen, nucleus accumbens (NAcc), and globus pallidus in AN.
METHODS
The present study combined data from two existing studies resulting in a sample size of 46 women with AN and 56 age-matched healthy comparison (HC) women. Group differences in volume and shape of the regions of interest were examined. Within the AN group, the impact of eating disorder characteristics on volume and shape of the basal ganglia regions were also explored.
RESULTS
The shape analyses revealed inward deformations in the left caudate, right NAcc, and bilateral ventral and internus globus pallidus, and outward deformations in the right middle and posterior globus pallidus in the AN group.
CONCLUSIONS
The present findings appear to fit with the theoretical models suggesting that there are alterations in the basal ganglia regions associated with habit formation and reward processing in AN. Further investigation of structural and functional connectivity of these regions in AN as well as their role in recovery would be of interest.
Topics: Adult; Anorexia Nervosa; Basal Ganglia; Case-Control Studies; Caudate Nucleus; Female; Humans; Magnetic Resonance Imaging; Nucleus Accumbens; Organ Size; Putamen; Reward
PubMed: 31586464
DOI: 10.1016/j.appet.2019.104480 -
Progress in Brain Research 2007This is the introductory chapter to an edited volume comprising 18 chapters written by 38 specially selected authors covering the anatomy, physiology,... (Review)
Review
This is the introductory chapter to an edited volume comprising 18 chapters written by 38 specially selected authors covering the anatomy, physiology, biochemistry/pharmacology and behavioral aspects of GABA in the basal ganglia. In this chapter the various nuclei of the basal ganglia are defined and their cellular structure, connections and function reviewed in brief in order to provide an orientation for the subsequent 17 chapters.
Topics: Animals; Basal Ganglia; Corpus Striatum; Humans; Neural Inhibition; Neural Pathways; Neurotransmitter Agents; Substantia Nigra; Subthalamic Nucleus; Synaptic Transmission; gamma-Aminobutyric Acid
PubMed: 17499105
DOI: 10.1016/S0079-6123(06)60001-0 -
Journal of Neural Transmission (Vienna,... Jul 2016Besides their fundamental movement function evidenced by Parkinsonian deficits, the basal ganglia are involved in processing closely linked non-motor, cognitive and... (Review)
Review
Besides their fundamental movement function evidenced by Parkinsonian deficits, the basal ganglia are involved in processing closely linked non-motor, cognitive and reward information. This review describes the reward functions of three brain structures that are major components of the basal ganglia or are closely associated with the basal ganglia, namely midbrain dopamine neurons, pedunculopontine nucleus, and striatum (caudate nucleus, putamen, nucleus accumbens). Rewards are involved in learning (positive reinforcement), approach behavior, economic choices and positive emotions. The response of dopamine neurons to rewards consists of an early detection component and a subsequent reward component that reflects a prediction error in economic utility, but is unrelated to movement. Dopamine activations to non-rewarded or aversive stimuli reflect physical impact, but not punishment. Neurons in pedunculopontine nucleus project their axons to dopamine neurons and process sensory stimuli, movements and rewards and reward-predicting stimuli without coding outright reward prediction errors. Neurons in striatum, besides their pronounced movement relationships, process rewards irrespective of sensory and motor aspects, integrate reward information into movement activity, code the reward value of individual actions, change their reward-related activity during learning, and code own reward in social situations depending on whose action produces the reward. These data demonstrate a variety of well-characterized reward processes in specific basal ganglia nuclei consistent with an important function in non-motor aspects of motivated behavior.
Topics: Animals; Basal Ganglia; Dopamine; Dopamine Agents; Dopaminergic Neurons; Humans; Motivation; Reward
PubMed: 26838982
DOI: 10.1007/s00702-016-1510-0 -
Current Biology : CB Oct 2016The lamprey belongs to the phylogenetically oldest group of vertebrates that diverged from the mammalian evolutionary line 560 million years ago. A comparison between... (Review)
Review
The lamprey belongs to the phylogenetically oldest group of vertebrates that diverged from the mammalian evolutionary line 560 million years ago. A comparison between the lamprey and mammalian basal ganglia establishes a detailed similarity regarding its input from cortex/pallium and thalamus, as well as its intrinsic organisation and projections of the output nuclei. This means that the basal ganglia circuits now present in rodents and primates most likely had evolved already at the dawn of vertebrate evolution. This includes the 'direct pathway' with striatal projection neurons (SPNs) expressing dopamine D1 receptors, which act to inhibit the tonically active GABAergic output neurons in globus pallidus interna and substantia nigra pars reticulata that at rest keep the brainstem motor centres under tonic inhibition. The 'indirect pathway' with dopamine D2 receptor-expressing SPNs and intrinsic basal ganglia nuclei is also conserved. The net effect of the direct pathway is to disinhibit brainstem motor centres and release motor programs, while the indirect pathway instead will suppress motor activity. Transmitters, connectivity and membrane properties are virtually identical in lamprey and rodent basal ganglia. We predict that the basal ganglia contains a series of modules each controlling a given pattern of behaviour including locomotion, eye-movements, posture, and chewing that contain both the direct pathway to release a motor program and the indirect pathway to inhibit competing behaviours. The phasic dopamine input serves value-based decisions and motor learning. During vertebrate evolution with a progressively more diverse motor behaviour, the number of modules will have increased progressively. These new modules with a similar design will be used to control newly developed patterns of behaviour - a process referred to as exaptation.
Topics: Animals; Basal Ganglia; Biological Evolution; Lampreys; Mammals; Vertebrates
PubMed: 27780050
DOI: 10.1016/j.cub.2016.06.041 -
Parkinsonism & Related Disorders Feb 2019Drawing on the seminal work of DeLong, Albin, and Young, we have now entered an era of basal ganglia neuromodulation. Understanding, re-evaluating, and leveraging the... (Review)
Review
INTRODUCTION
Drawing on the seminal work of DeLong, Albin, and Young, we have now entered an era of basal ganglia neuromodulation. Understanding, re-evaluating, and leveraging the lessons learned from neuromodulation will be crucial to facilitate an increased and improved application of neuromodulation in human disease.
METHODS
We will focus on deep brain stimulation (DBS) - the most common form of basal ganglia neuromodulation - however, similar principles can apply to other neuromodulation modalities. We start with a brief review of DBS for Parkinson's disease, essential tremor, dystonia, and Tourette syndrome. We then review hallmark studies on basal ganglia circuits and electrophysiology resulting from decades of experience in neuromodulation. The organization and content of this paper follow Dr. Okun's Lecture from the 2018 Parkinsonism and Related Disorders World Congress.
RESULTS
Information gained from neuromodulation has led to an expansion of the basal ganglia rate model, an enhanced understanding of nuclei dynamics, an emerging focus on pathological oscillations, a revision of the tripartite division of the basal ganglia, and a redirected focus toward individualized symptom-specific stimulation. Though there have been many limitations of the basal ganglia "box model," the construct provided the necessary foundation to advance the field. We now understand that information in the basal ganglia is encoded through complex neural responses that can be reliably measured and used to infer disease states for clinical translation.
CONCLUSIONS
Our deepened understanding of basal ganglia physiology will drive new neuromodulation strategies such as adaptive DBS or cell-specific neuromodulation through the use of optogenetics.
Topics: Animals; Basal Ganglia; Deep Brain Stimulation; Humans; Movement Disorders; Neural Pathways
PubMed: 30658883
DOI: 10.1016/j.parkreldis.2019.01.009 -
Journal of Neuroscience Research Jul 2022Complex regional pain syndrome (CRPS) is a painful condition commonly accompanied by movement disturbances and often affects the upper limbs. The basal ganglia motor...
Complex regional pain syndrome (CRPS) is a painful condition commonly accompanied by movement disturbances and often affects the upper limbs. The basal ganglia motor loop is central to movement, however, non-motor basal ganglia loops are involved in pain, sensory integration, visual processing, cognition, and emotion. Systematic evaluation of each basal ganglia functional loop and its relation to motor and non-motor disturbances in CRPS has not been investigated. We recruited 15 upper limb CRPS and 45 matched healthy control subjects. Using functional magnetic resonance imaging, infraslow oscillations (ISO) and resting-state functional connectivity in motor and non-motor basal ganglia loops were investigated using putamen and caudate seeds. Compared to controls, CRPS subjects displayed increased ISO power in the putamen contralateral to the CRPS affected limb, specifically, in contralateral putamen areas representing the supplementary motor area hand, motor hand, and motor tongue. Furthermore, compared to controls, CRPS subjects displayed increased resting connectivity between these putaminal areas as well as from the caudate body to cortical areas such as the primary motor cortex, supplementary and cingulate motor areas, parietal association areas, and the orbitofrontal cortex. These findings demonstrate changes in basal ganglia loop function in CRPS subjects and may underpin motor disturbances of CRPS.
Topics: Basal Ganglia; Complex Regional Pain Syndromes; Hand; Humans; Magnetic Resonance Imaging; Movement
PubMed: 35441738
DOI: 10.1002/jnr.25057 -
Journal of Neural Transmission (Vienna,... Apr 2021Dystonia is a disabling movement disorder characterized by abnormal postures or patterned and repetitive movements due to co-contraction of muscles in proximity to... (Review)
Review
Dystonia is a disabling movement disorder characterized by abnormal postures or patterned and repetitive movements due to co-contraction of muscles in proximity to muscles desired for a certain movement. Important and well-established pathophysiological concepts are the impairment of sensorimotor integration, a loss of inhibitory control on several levels of the central nervous system and changes in synaptic plasticity. These mechanisms collectively contribute to an impairment of the gating function of the basal ganglia which results in an insufficient suppression of noisy activity and an excessive activation of cortical areas. In addition to this traditional view, a plethora of animal, genetic, imaging and electrophysiological studies highlight the role of the (1) cerebellum, (2) the cerebello-thalamic connection and (3) the functional interplay between basal ganglia and the cerebellum in the pathophysiology of dystonia. Another emerging topic is the better understanding of the microarchitecture of the striatum and its implications for dystonia. The striosomes are of particular interest as they likely control the dopamine release via inhibitory striato-nigral projections. Striosomal dysfunction has been implicated in hyperkinetic movement disorders including dystonia. This review will provide a comprehensive overview about the current understanding of the functional neuroanatomy and pathophysiology of dystonia and aims to move the traditional view of a 'basal ganglia disorder' to a network perspective with a dynamic interplay between cortex, basal ganglia, thalamus, brainstem and cerebellum.
Topics: Animals; Basal Ganglia; Corpus Striatum; Dystonia; Dystonic Disorders; Neuroanatomy
PubMed: 33486625
DOI: 10.1007/s00702-021-02299-y