scholarly journals Interaction of Indirect and Hyperdirect Pathways on Synchrony and Tremor-Related Oscillation in the Basal Ganglia

2021 ◽  
Vol 2021 ◽  
pp. 1-16
Author(s):  
Xia Shi ◽  
Danwen Du ◽  
Yuan Wang
Keyword(s):  
Basal Ganglia ◽  
Globus Pallidus ◽  
Subthalamic Nucleus ◽  
Low Frequency ◽  
Oscillatory Activity ◽  
Theta Band ◽  
Dynamical Mechanism ◽  
Parkinsonian Tremor ◽  
Cortical Input ◽  
Novel Treatments

Low-frequency oscillatory activity (3-9 Hz) and increased synchrony in the basal ganglia (BG) are recognized to be crucial for Parkinsonian tremor. However, the dynamical mechanism underlying the tremor-related oscillations still remains unknown. In this paper, the roles of the indirect and hyperdirect pathways on synchronization and tremor-related oscillations are considered based on a modified Hodgkin-Huxley model. Firstly, the effects of indirect and hyperdirect pathways are analysed individually, which show that increased striatal activity to the globus pallidus external (GPe) or strong cortical gamma input to the subthalamic nucleus (STN) is sufficient to promote synchrony and tremor-related oscillations in the BG network. Then, the mutual effects of both pathways are analysed by adjusting the related currents simultaneously. Our results suggest that synchrony and tremor-related oscillations would be strengthened if the current of these two paths are in relative imbalance. And the network tends to be less synchronized and less tremulous when the frequency of cortical input is in the theta band. These findings may provide novel treatments in the cortex and striatum to alleviate symptoms of tremor in Parkinson’s disease.

scholarly journals The Subthalamic Nucleus in Primary Dystonia: Single-Unit Discharge Characteristics

2009 ◽  
Vol 102 (6) ◽  
pp. 3740-3752 ◽  
Author(s):  
Lauren E. Schrock ◽  
Jill L. Ostrem ◽  
Robert S. Turner ◽  
Shoichi A. Shimamoto ◽  
Philip A. Starr
Keyword(s):  
Basal Ganglia ◽  
Globus Pallidus ◽  
Subthalamic Nucleus ◽  
Single Unit ◽  
Discharge Rate ◽  
Receptive Fields ◽  
Principal Component ◽  
Oscillatory Activity ◽  
Inhibitory Input ◽  
Primary Dystonia

Most models of dystonia pathophysiology predict alterations of activity in the basal ganglia thalamocortical motor circuit. The globus pallidus interna (GPi) shows bursting and oscillatory neuronal discharge in both human dystonia and in animal models, but it is not clear which intrinsic basal ganglia pathways are implicated in this abnormal output. The subthalamic nucleus (STN) receives prominent excitatory input directly from cortical areas implicated in dystonia pathogenesis and inhibitory input from the external globus pallidus. The goal of this study was to elucidate the role of the STN in dystonia by analyzing STN neuronal discharge in patients with idiopathic dystonia. Data were collected in awake patients undergoing microelectrode recording for implantation of STN deep brain stimulation electrodes. We recorded 62 STN neurons in 9 patients with primary dystonia. As a comparison group, we recorded 143 STN neurons in 20 patients with Parkinson's disease (PD). Single-unit activity was discriminated off-line by principal component analysis and evaluated with respect to discharge rate, bursting, and oscillatory activity. The mean STN discharge rate in dystonia patients was 26.3 Hz (SD 13.6), which was lower than that in the PD patients (35.6 Hz, SD 15.2), but higher than published values for subjects without basal ganglia dysfunction. Oscillatory activity was found in both disorders, with a higher proportion of units oscillating in the beta range in PD. Bursting discharge was a prominent feature of both dystonia and PD, whereas sensory receptive fields were expanded in PD compared with dystonia. The STN firing characteristics, in conjunction with those previously published for GPi, suggest that bursting and oscillatory discharge in basal ganglia output may be transmitted via pathways involving the STN and provide a pathophysiologic rationale for STN as a surgical target in dystonia.

Subthalamo-Pallidal Circuit

2017 ◽  
pp. 143-150
Author(s):  
Charles J. Wilson
Keyword(s):  
Basal Ganglia ◽  
Substantia Nigra ◽  
Globus Pallidus ◽  
Subthalamic Nucleus ◽  
Substantia Nigra Pars Reticulata ◽  
Modern Methods

The subthalamo-pallidal system constitutes the second layer of circuitry in the basal ganglia, downstream of the striatum. It consists of four nuclei. Two of them, the external segment of the globus pallidus (GPe) and subthalamic nucleus (STN), make their connections primarily within the basal ganglia. The others, the internal segment of the globus pallidus (GPi) and the substantia nigra pars reticulata (SNr), are the output nuclei of the basal ganglia. Collectively, their axons distribute collaterals to all the targets of the basal ganglia. Rare interneurons have been reported in each of them from studies of Golgi-stained preparations, but they have not so far been confirmed using more modern methods. The circuit as described here is based primarily on studies of the axonal arborizations of neurons stained individually by intracellular or juxtacellular labeling.

scholarly journals The primate subthalamic nucleus. II. Neuronal activity in the MPTP model of parkinsonism

1994 ◽  
Vol 72 (2) ◽  
pp. 507-520 ◽  
Author(s):  
H. Bergman ◽  
T. Wichmann ◽  
B. Karmon ◽  
M. R. DeLong
Keyword(s):  
Firing Rate ◽  
Subthalamic Nucleus ◽  
Neuronal Activity ◽  
Low Frequency ◽  
Oscillatory Activity ◽  
Autocorrelation Analysis ◽  
Periodic Activity ◽  
Average Firing Rate ◽  
Mptp Treatment ◽  
Highly Correlated

1. The neuronal mechanisms underlying the major motor signs of Parkinson's disease were studied in the basal ganglia of parkinsonian monkeys. Three African green monkeys were systemically treated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) until parkinsonian signs, including akinesia, rigidity, and a prominent 4- to 8-Hz tremor, appeared. The activity of neurons in the subthalamic nucleus (STN) and in the internal segment of the globus pallidus (GPi) was recorded before (STN, n = 220 cells; GPi, n = 175 cells) and after MPTP treatment (STN, n = 326 cells; GPi, n = 154 cells). 2. In STN the spontaneous firing rate was significantly increased from 19 +/- 10 (SD) spikes/s before to 26 +/- 15 spikes/s after MPTP treatment. Division of STN neurons recorded after MPTP treatment into cells with rhythmic bursts of discharge occurring at 4–8 Hz (as defined by autocorrelation analysis) and neurons without 4- to 8-Hz periodic activity revealed an even more prominent increase in the firing rate of the 4- to 8-Hz oscillatory neurons. 3. In GPi overall changes in the average firing rate of cells were inconsistent between different animals and behavioral states. However, the average firing rate of the subpopulation of neurons with 4- to 8-Hz periodic oscillatory activity after treatment with MPTP was significantly increased over that of all neurons before MPTP treatment (from 53 to 76 spikes/s, averaged across monkeys). 4. In the normal state the percentage of neurons with burst discharges (as defined by autocorrelation analysis) was 69% and 78% in STN and GPi, respectively. After MPTP treatment the percentage of cells that discharged in bursts was increased to 79% and 89%, respectively. At the same time the average burst duration decreased (from 121 +/- 98 to 81 +/- 99 ms in STN and from 213 +/- 120 to 146 +/- 134 ms in GPi) with no significant change in the average number of spikes per burst. 5. Periodic oscillatory neuronal activity at low frequency, highly correlated with tremor, was detected in a large number of cells in STN and GPi after MPTP treatment (average oscillation frequency 6.0 and 5.1 Hz, respectively). The autocorrelograms of spike trains of these neurons confirm that the periodic oscillatory activity was very stable. The percentage of cells with 4- to 8-Hz periodic activity significantly increased from 2% to 16% in STN and from 0.6% to 25% in GPi with the MPTP treatment.(ABSTRACT TRUNCATED AT 400 WORDS)

scholarly journals Basal ganglia and cerebellar contributions to vocal emotion processing: a high resolution fMRI study

2020 ◽  
Author(s):  
Leonardo Ceravolo ◽  
Sascha Frühholz ◽  
Jordan Pierce ◽  
Didier Grandjean ◽  
Julie Péron
Keyword(s):  
Basal Ganglia ◽  
High Resolution ◽  
Globus Pallidus ◽  
Subthalamic Nucleus ◽  
Effective Connectivity ◽  
Emotion Processing ◽  
Brain Regions ◽  
Fmri Study ◽  
Vocal Emotion

AbstractUntil recently, brain networks underlying emotional voice prosody decoding and processing were focused on modulations in primary and secondary auditory, ventral frontal and prefrontal cortices, and the amygdala. Growing interest for a specific role of the basal ganglia and cerebellum was recently brought into the spotlight. In the present study, we aimed at characterizing the role of such subcortical brain regions in vocal emotion processing, at the level of both brain activation and functional and effective connectivity, using high resolution functional magnetic resonance imaging. Variance explained by low-level acoustic parameters (fundamental frequency, voice energy) was also modelled. Wholebrain data revealed expected contributions of the temporal and frontal cortices, basal ganglia and cerebellum to vocal emotion processing, while functional connectivity analyses highlighted correlations between basal ganglia and cerebellum, especially for angry voices. Seed-to-seed and seed-to-voxel effective connectivity revealed direct connections within the basal ganglia ̶ especially between the putamen and external globus pallidus ̶ and between the subthalamic nucleus and the cerebellum. Our results speak in favour of crucial contributions of the basal ganglia, especially the putamen, external globus pallidus and subthalamic nucleus, and several cerebellar lobules and nuclei for an efficient decoding of and response to vocal emotions.

Understanding Parkinsonian Handwriting Through a Computational Model of Basal Ganglia

2008 ◽  
Vol 20 (10) ◽  
pp. 2491-2525 ◽  
Author(s):  
Garipelli Gangadhar ◽  
Denny Joseph ◽  
V. Srinivasa Chakravarthy
Keyword(s):  
Basal Ganglia ◽  
Computational Model ◽  
Globus Pallidus ◽  
Subthalamic Nucleus ◽  
Line Contour ◽  
Velocity Fluctuations ◽  
Signaling Model ◽  
Tip Velocity ◽  
Handwriting Generation

Handwriting in Parkinson's disease (PD) is typically characterized by micrographia, jagged line contour, and unusual fluctuations in pen tip velocity. Although PD handwriting features have been used for diagnostics, they are not based on a signaling model of basal ganglia (BG). In this letter, we present a computational model of handwriting generation that highlights the role of BG. When PD conditions like reduced dopamine and altered dynamics of the subthalamic nucleus and globus pallidus externa subsystems are simulated, the handwriting produced by the model manifested characteristic PD handwriting distortions like micrographia and velocity fluctuations. Our approach to PD modeling is in tune with the perspective that PD is a dynamic disease.

scholarly journals Hypersynchrony despite pathologically reduced beta oscillations in patients with Parkinson's disease: a pharmaco-magnetoencephalography study

2014 ◽  
Vol 112 (7) ◽  
pp. 1739-1747 ◽  
Author(s):  
Elizabeth Heinrichs-Graham ◽  
Max J. Kurz ◽  
Katherine M. Becker ◽  
Pamela M. Santamaria ◽  
Howard E. Gendelman ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Basal Ganglia ◽  
Subthalamic Nucleus ◽  
Neurodegenerative Disorder ◽  
Oscillatory Activity ◽  
Cortical Motor ◽  
Motor Network ◽  
Neurophysiological Studies ◽  
Gait Abnormalities

Parkinson's disease (PD) is a progressive debilitating neurodegenerative disorder clinically manifest by motor, posture and gait abnormalities. Human neurophysiological studies recording local field potentials within the subthalamic nucleus and scalp-based electroencephalography have shown pathological beta synchrony throughout the basal ganglia-thalamic-cortical motor network in PD. Notably, suppression of this pathological beta synchrony by dopamine replacement therapy or deep-brain stimulation has been associated with improved motor function. However, due to the invasive nature of these studies, it remains unknown whether this “pathological beta” is actually stronger than that observed in healthy demographically matched controls. We used magnetoencephalography to investigate neuronal synchrony and oscillatory amplitude in the beta range and lower frequencies during the resting state in patients with PD and a matched group of patients without neurological disease. Patients with PD were studied both in the practically defined drug “OFF” state, and after administration of dopamine replacements. We found that beta oscillatory amplitude was reduced bilaterally in the primary motor regions of unmedicated patients with PD compared with controls. Administration of dopaminergic medications significantly increased beta oscillatory activity, thus having a normalizing effect. Interestingly, we also found significantly stronger beta synchrony (i.e., hypersynchrony) between the primary motor regions in unmedicated patients with PD compared with controls, and that medication reduced this coupling which is in agreement with the intraoperative studies. These results are consistent with the known functionality of the basal ganglia-thalamic-cortical motor circuit and the likely consequences of beta hypersynchrony in the subthalamic nucleus of patients with PD.

Early-onset cortico-cortical synchronization in the hemiparkinsonian rat model

2015 ◽  
Vol 113 (3) ◽  
pp. 925-936 ◽  
Author(s):  
B. N. Jávor-Duray ◽  
M. Vinck ◽  
M. van der Roest ◽  
A. B. Mulder ◽  
C. J. Stam ◽  
...  
Keyword(s):  
Basal Ganglia ◽  
Motor Cortex ◽  
Granger Causality ◽  
Subthalamic Nucleus ◽  
Spectral Power ◽  
Field Potential ◽  
Cell Loss ◽  
Oscillatory Activity ◽  
Connectivity Pattern ◽  
Phase Lag

Changes in synchronized neuronal oscillatory activity are reported in both cortex and basal ganglia of Parkinson's disease patients. The origin of these changes, in particular their relationship with the progressive nigrostriatal dopaminergic denervation, is unknown. Therefore, in the present study we studied interregional neuronal synchronization in motor cortex and basal ganglia during the development of dopaminergic degeneration induced by a unilateral infusion of 6-hydroxydopamine (6-OHDA) into the rat medial forebrain bundle. We performed serial local field potential recordings bilaterally in the motor cortex and the subthalamic nucleus of the lesioned hemisphere prior to, during, and after development of the nigrostriatal dopaminergic cell loss. We obtained signal from freely moving rats in both resting and walking conditions, and we computed local spectral power, interregional synchronization (using phase lag index), and directionality (using Granger causality). After neurotoxin injection the first change in phase lag index was an increment in cortico-cortical synchronization. We observed increased bidirectional Granger causality in the beta frequency band between cortex and subthalamic nucleus within the lesioned hemisphere. In the walking condition, the 6-OHDA lesion-induced changes in synchronization resembled that of the resting state, whereas the changes in Granger causality were less pronounced after the lesion. Considering the relatively preserved connectivity pattern of the cortex contralateral to the lesioned side and the early emergence of increased cortico-cortical synchronization during development of the 6-OHDA lesion, we suggest a putative compensatory role of cortico-cortical coupling.

A basal ganglia pacemaker formed by the subthalamic nucleus and external globus pallidus

Nature ◽  
10.1038/23281 ◽  
1999 ◽  
Vol 400 (6745) ◽  
pp. 677-682 ◽  
Author(s):  
Dietmar Plenz ◽  
Stephen T. Kital
Keyword(s):  
Basal Ganglia ◽  
Globus Pallidus ◽  
Subthalamic Nucleus
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