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loops of the basal ganglia

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https://www.readbyqxmd.com/read/29236966/neuronal-inhibition-and-synaptic-plasticity-of-basal-ganglia-neurons-in-parkinson-s-disease
#1
Luka Milosevic, Suneil K Kalia, Mojgan Hodaie, Andres M Lozano, Alfonso Fasano, Milos R Popovic, William D Hutchison
Deep brain stimulation of the subthalamic nucleus is an effective treatment for Parkinson's disease symptoms. The therapeutic benefits of deep brain stimulation are frequency-dependent, but the underlying physiological mechanisms remain unclear. To advance deep brain stimulation therapy an understanding of fundamental mechanisms is critical. The objectives of this study were to (i) compare the frequency-dependent effects on cell firing in subthalamic nucleus and substantia nigra pars reticulata; (ii) quantify frequency-dependent effects on short-term plasticity in substantia nigra pars reticulata; and (iii) investigate effects of continuous long-train high frequency stimulation (comparable to conventional deep brain stimulation) on synaptic plasticity...
December 11, 2017: Brain: a Journal of Neurology
https://www.readbyqxmd.com/read/29236724/the-role-of-cortical-oscillations-in-a-spiking-neural-network-model-of-the-basal-ganglia
#2
Zafeirios Fountas, Murray Shanahan
Although brain oscillations involving the basal ganglia (BG) have been the target of extensive research, the main focus lies disproportionally on oscillations generated within the BG circuit rather than other sources, such as cortical areas. We remedy this here by investigating the influence of various cortical frequency bands on the intrinsic effective connectivity of the BG, as well as the role of the latter in regulating cortical behaviour. To do this, we construct a detailed neural model of the complete BG circuit based on fine-tuned spiking neurons, with both electrical and chemical synapses as well as short-term plasticity between structures...
2017: PloS One
https://www.readbyqxmd.com/read/29224175/thalamic-interactions-of-cerebellum-and-basal-ganglia
#3
REVIEW
Andreas Hintzen, Esther Annegret Pelzer, Marc Tittgemeyer
Cerebellum and basal ganglia are reciprocally interconnected with the neocortex via oligosynaptic loops. The signal pathways of these loops predominantly converge in motor areas of the frontal cortex and are mainly segregated on subcortical level. Recent evidence, however, indicates subcortical interaction of these systems. We have reviewed literature that addresses the question whether, and to what extent, projections of main output nuclei of basal ganglia (reticular part of the substantia nigra, internal segment of the globus pallidus) and cerebellum (deep cerebellar nuclei) interact with each other in the thalamus...
December 9, 2017: Brain Structure & Function
https://www.readbyqxmd.com/read/29157667/a-case-of-multiple-system-atrophy-parkinsonian-type-with-stuttering-and-palilalia-like-dysfluencies-and-putaminal-atrophy
#4
Yoshikazu Kikuchi, Toshiro Umezaki, Taira Uehara, Hiroo Yamaguchi, Koji Yamashita, Akio Hiwatashi, Motohiro Sawatsubashi, Kazuo Adachi, Yumi Yamaguchi, Daisuke Murakami, Jun-Ichi Kira, Takashi Nakagawa
Both developmental and acquired stuttering are related to the function of the basal ganglia-thalamocortical loop, which includes the putamen. Here, we present a case of stuttering- and palilalia-like dysfluencies that manifested as an early symptom of multiple system atrophy-parkinsonian type (MSA-P) and bilateral atrophy of the putamen. The patient was a 72-year-old man with no history of developmental stuttering who presented with a stutter for consultation with our otorhinolaryngology department. The patient was diagnosed with MSA-P based on parkinsonism, autonomic dysfunction, and bilateral putaminal atrophy revealed by T2-weighted magnetic resonance imaging...
November 14, 2017: Journal of Fluency Disorders
https://www.readbyqxmd.com/read/29156412/a-system-level-mathematical-model-of-basal-ganglia-motor-circuit-for-kinematic-planning-of-arm-movements
#5
Armin Salimi-Badr, Mohammad Mehdi Ebadzadeh, Christian Darlot
In this paper, a novel system-level mathematical model of the Basal Ganglia (BG) for kinematic planning, is proposed. An arm composed of several segments presents a geometric redundancy. Thus, selecting one trajectory among an infinite number of possible ones requires overcoming redundancy, according to some kinds of optimization. Solving this optimization is assumed to be the function of BG in planning. In the proposed model, first, a mathematical solution of kinematic planning is proposed for movements of a redundant arm in a plane, based on minimizing energy consumption...
November 10, 2017: Computers in Biology and Medicine
https://www.readbyqxmd.com/read/29138510/high-fat-diet-induced-obesity-and-insulin-resistance-are-characterized-by-differential-beta-oscillatory-signaling-of-the-limbic-cortico-basal-ganglia-loop
#6
Lukas Maurer, Hui Tang, Jens K Haumesser, Jennifer Altschüler, Andrea A Kühn, Joachim Spranger, Christoph van Riesen
The concept of brain circuit disorders has been proposed for a variety of neuropsychiatric diseases, characterized by pathological disturbances of neuronal networks including changes in oscillatory signaling of re-entrant cortico-subcortical loops in the basal ganglia system. Parts of this circuitry play a pivotal role in energy homeostasis. We therefore investigated whether high-fat diet (HFD) induced obesity is associated with changes in oscillatory signaling in the limbic cortico-basal ganglia loop. We performed multi-site in-vivo electrophysiological recordings of local field potentials within this network under urethane anesthesia in adult rats after 4 weeks of HFD feeding compared to age-matched controls...
November 14, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29130551/a-localized-pallidal-physiomarker-in-cervical-dystonia
#7
Wolf-Julian Neumann, Andreas Horn, Siobhan Ewert, Julius Huebl, Christof Brücke, Colleen Slentz, Gerd-Helge Schneider, Andrea A Kühn
OBJECTIVE: Deep brain stimulation (DBS) allows for direct recordings of neuronal activity from the human basal ganglia. In Parkinson's disease, a disease-specific physiomarker was identified that is now used to investigate adaptive closed-loop stimulation in first studies. In dystonia such a physiomarker is missing. METHODS: Pallidal oscillations were recorded from 153 contact pairs in 27 patients. We investigated whether power amplitudes in theta and beta bands correlate with dystonic symptom severity across patients...
November 11, 2017: Annals of Neurology
https://www.readbyqxmd.com/read/29060276/closed-loop-low-frequency-dbs-restores-thalamocortical-relay-fidelity-in-a-computational-model-of-the-motor-loop
#8
Han D Huang, Sabato Santaniello
Closed-loop modulation of deep brain stimulation (DBS) of the subthalamic nucleus (STN) in Parkinson's disease (PD) is investigated to automatically adjust the stimulation to the patients' conditions, optimize the clinical outcomes, and reduce the energy requirements. This study proposes a closed-loop control system for real-time adaptation of the STN-DBS amplitude based on the neural activity in the motor thalamus. Population-averaged post-stimulus time histograms are used to measure the average effects of STN-DBS on the thalamocortical neurons and a L2-norm minimization problem is solved to design the control algorithm, while the frequency of stimulation is kept constant...
July 2017: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/29038241/sensorimotor-processing-in-the-basal-ganglia-leads-to-transient-beta-oscillations-during-behavior
#9
Amin Mirzaei, Arvind Kumar, Daniel Leventhal, Nicolas Mallet, Ad Aertsen, Joshua Berke, Robert Schmidt
Brief epochs of beta oscillations have been implicated in sensorimotor control in the basal ganglia of task-performing healthy animals. However, which neural processes underlie their generation and how they are affected by sensorimotor processing remains unclear. To determine the mechanisms underlying transient beta oscillations in the local field potential (LFP), we combined computational modeling of the subthalamo-pallidal network for the generation of beta oscillations with realistic stimulation patterns derived from single unit data...
October 16, 2017: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
https://www.readbyqxmd.com/read/29028949/pyramidal-cell-subtypes-and-their-synaptic-connections-in-layer-5-of-rat-frontal-cortex
#10
Yasuo Kawaguchi
The frontal cortical areas make a coordinated response that generates appropriate behavior commands, using individual local circuits with corticostriatal and corticocortical connections in longer time scales than sensory areas. In secondary motor cortex (M2), situated between the prefrontal and primary motor areas, major subtypes of layer 5 corticostriatal cells are crossed-corticostriatal (CCS) cells innervating both sides of striatum, and corticopontine (CPn) cells projecting to the ipsilateral striatum and pontine nuclei...
December 1, 2017: Cerebral Cortex
https://www.readbyqxmd.com/read/29017141/premonitory-urges-and-tics-in-tourette-syndrome-computational-mechanisms-and-neural-correlates
#11
REVIEW
Vasco A Conceição, Ângelo Dias, Ana C Farinha, Tiago V Maia
Tourette syndrome is characterized by open motor behaviors - tics - but another crucial aspect of the disorder is the presence of premonitory urges: uncomfortable sensations that typically precede tics and are temporarily alleviated by tics. We review the evidence implicating the somatosensory cortices and the insula in premonitory urges and the motor cortico-basal ganglia-thalamo-cortical loop in tics. We consider how these regions interact during tic execution, suggesting that the insula plays an important role as a nexus linking the sensory and emotional character of premonitory urges with their translation into tics...
October 2017: Current Opinion in Neurobiology
https://www.readbyqxmd.com/read/28945119/reduced-structural-connectivity-in-frontostriatal-white-matter-tracts-in-the-associative-loop-in-schizophrenia
#12
James J Levitt, Paul G Nestor, Laura Levin, Paula Pelavin, Pan Lin, Marek Kubicki, Robert W McCarley, Martha E Shenton, Yogesh Rathi
OBJECTIVE: The striatum receives segregated and integrative white matter tracts from the cortex facilitating information processing in the cortico-basal ganglia network. The authors examined both types of input tracts in the striatal associative loop in chronic schizophrenia patients and healthy control subjects. METHOD: Structural and diffusion MRI scans were acquired on a 3-T system from 26 chronic schizophrenia patients and 26 matched healthy control subjects...
November 1, 2017: American Journal of Psychiatry
https://www.readbyqxmd.com/read/28915150/tics-and-tourette-a-clinical-pathophysiological-and-etiological-review
#13
Russell C Dale
PURPOSE OF REVIEW: Describe developments in the etiological understanding of Tourette syndrome. RECENT FINDINGS: Tourette syndrome is a complex heterogenous clinical syndrome, which is not a unitary entity. Pathophysiological models describe gamma-aminobutyric acid-ergic-associated disinhibition of cortico-basal ganglia motor, sensory and limbic loops. MRI studies support basal ganglia volume loss, with additional white matter and cerebellar changes. Tourette syndrome cause likely involves multiple vulnerability genes and environmental factors...
December 2017: Current Opinion in Pediatrics
https://www.readbyqxmd.com/read/28904447/levodopa-induced-dyskinesia-clinical-features-pathophysiology-and-medical-management
#14
Sanjay Pandey, Prachaya Srivanitchapoom
Levodopa-induced dyskinesia (LID) is commonly seen in Parkinson's disease patients treated with levodopa. This side effect is usually encountered after long duration of treatment, but occasionally, this may be seen even after few days or months of treatment. LID is broadly classified as peak-dose dyskinesia, wearing-off or off-period dyskinesia, and diphasic dyskinesia. Pathogenesis of LID is complex, and different neurotransmitters such as dopamine, glutamine, adenosine, and gamma-aminobutyric acid play important role altering the normal physiology of direct and indirect pathway of cortico-basal ganglia-thalamic loop responsible for fine motor control...
July 2017: Annals of Indian Academy of Neurology
https://www.readbyqxmd.com/read/28893517/differential-effects-of-levodopa-and-apomorphine-on-neuronal-population-oscillations-in-the-cortico-basal-ganglia-loop-circuit-in-vivo-in-experimental-parkinsonism
#15
Johanna Kühn, Jens K Haumesser, Maximilian H Beck, Jennifer Altschüler, Andrea A Kühn, Vadim V Nikulin, Christoph van Riesen
The current pharmacotherapy of Parkinson's disease (PD) is primarily based on two classes of drugs: dopamine precursors, namely levodopa, and dopamine receptor agonists, such as apomorphine. Although both types of agents exert their beneficial clinical effects on motor and non-motor symptoms in PD via dopamine receptors, clinical efficiency and side effects differ substantially between levodopa and apomorphine. Levodopa can provide a greater symptomatic relief than dopamine receptor agonists. However, because long-term levodopa use is associated with early debilitating motor fluctuations, dopamine receptor agonists are often recommended in younger patients...
December 2017: Experimental Neurology
https://www.readbyqxmd.com/read/28871419/thalamic-and-basal-ganglia-regions-are-involved-in-attentional-processing-of-behaviorally-significant-events-evidence-from-simultaneous-depth-and-scalp-eeg
#16
Anne-Kathrin Beck, Götz Lütjens, Kerstin Schwabe, Reinhard Dengler, Joachim K Krauss, Pascale Sandmann
Extensive descriptions exist on cortical responses to change in the acoustic environment. However, the involvement of subcortical regions is not well understood. Here we present simultaneous recordings of cortical and subcortical event-related potentials (ERPs) to different pure tones in patients undergoing surgery for deep brain stimulation (DBS). These patients had externalized electrodes in the subthalamic nucleus (STN), the ventrolateral posterior thalamus (VLp) or the globus pallidus internus (GPi). Subcortical and cortical ERPs were analyzed upon presentation of one frequent non-target stimulus and two infrequent stimuli, either being a target or a distractor stimulus...
September 4, 2017: Brain Structure & Function
https://www.readbyqxmd.com/read/28836295/microglia-may-compensate-for-dopaminergic-neuron-loss-in-experimental-parkinsonism-through-selective-elimination-of-glutamatergic-synapses-from-the-subthalamic-nucleus
#17
Hitomi Aono, Mohammed Emamussalehin Choudhury, Hiromi Higaki, Kazuya Miyanishi, Yuka Kigami, Kohdai Fujita, Jun-Ichi Akiyama, Hisaaki Takahashi, Hajime Yano, Madoka Kubo, Noriko Nishikawa, Masahiro Nomoto, Junya Tanaka
Parkinson's disease (PD) symptoms do not become apparent until most dopaminergic neurons in the substantia nigra pars compacta (SNc) degenerate, suggesting that compensatory mechanisms play a role. Here, we investigated the compensatory involvement of activated microglia in the SN pars reticulata (SNr) and the globus pallidus (GP) in a 6-hydroxydopamine-induced rat hemiparkinsonism model. Activated microglia accumulated more markedly in the SNr than in the SNc in the model. The cells had enlarged somata and expressed phagocytic markers CD68 and NG2 proteoglycan in a limited region of the SNr, where synapsin I- and postsynaptic density 95-immunoreactivities were reduced...
August 24, 2017: Glia
https://www.readbyqxmd.com/read/28835526/parkinsonism-and-vigilance-alteration-in-neural-oscillatory-activity-and-phase-amplitude-coupling-in-the-basal-ganglia-and-motor-cortex
#18
David Escobar Sanabria, Luke A Johnson, Shane D Nebeck, Jianyu Zhang, Matthew D Johnson, Kenneth B Baker, Gregory F Molnar, Jerrold L Vitek
Oscillatory neural activity in different frequency bands and phase-amplitude coupling (PAC) are hypothesized to be biomarkers of Parkinson's disease (PD) that could explain dysfunction in the motor circuit and be used for closed-loop deep brain stimulation (DBS). How these putative biomarkers change from the normal to the parkinsonian state across nodes in the motor circuit and within the same subject, however, remains unknown. In this study, we characterized how parkinsonism and vigilance altered oscillatory activity and PAC within the primary motor cortex (M1), subthalamic nucleus (STN), and globus pallidus (GP) in two nonhuman primates...
November 1, 2017: Journal of Neurophysiology
https://www.readbyqxmd.com/read/28833676/the-subthalamic-nucleus-external-globus-pallidus-loop-biases-exploratory-decisions-towards-known-alternatives-a-neuro-computational-study
#19
Javier Baladron, Atsushi Nambu, Fred H Hamker
Theories and models of the basal ganglia have mainly focused on the role of three different cortico-thalamic pathways: direct, indirect and hyperdirect. Although the indirect and the hyperdirect pathways are linked through the bidirectional connections between the subthalamic nucleus (STN) and the external globus pallidus (GPe), the role of their interactions has been mainly discussed in the context of a dysfunction (abnormal oscillations in Parkinson's disease) and not of its function. We here propose a novel role for the loop formed by the STN and the GPe...
August 22, 2017: European Journal of Neuroscience
https://www.readbyqxmd.com/read/28813460/mechanisms-for-pattern-specificity-of-deep-brain-stimulation-in-parkinson-s-disease
#20
Osvaldo Matías Velarde, Germán Mato, Damián Dellavale
Deep brain stimulation (DBS) has become a widely used technique for treating advanced stages of neurological and psychiatric illness. In the case of motor disorders related to basal ganglia (BG) dysfunction, several mechanisms of action for the DBS therapy have been identified which might be involved simultaneously or in sequence. However, the identification of a common key mechanism underlying the clinical relevant DBS configurations has remained elusive due to the inherent complexity related to the interaction between the electrical stimulation and the neural tissue, and the intricate circuital structure of the BG-thalamocortical network...
2017: PloS One
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