Synaptic network structure shapes cortically evoked spatio-temporal responses of STN and GPe neurons in a computational model

IntroductionThe basal ganglia (BG) are involved in motor control and play an essential role in movement disorders such as hemiballismus, dystonia, and Parkinson's disease. Neurons in the motor part of the BG respond to passive movement or stimulation of different body parts and to stimulation o...

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Main Authors: Justus A. Kromer, Hemant Bokil, Peter A. Tass
Format: Article
Language:English
Published: Frontiers Media S.A. 2023-08-01
Series:Frontiers in Neuroinformatics
Subjects:
Online Access:https://www.frontiersin.org/articles/10.3389/fninf.2023.1217786/full
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author Justus A. Kromer
Hemant Bokil
Peter A. Tass
author_facet Justus A. Kromer
Hemant Bokil
Peter A. Tass
author_sort Justus A. Kromer
collection DOAJ
description IntroductionThe basal ganglia (BG) are involved in motor control and play an essential role in movement disorders such as hemiballismus, dystonia, and Parkinson's disease. Neurons in the motor part of the BG respond to passive movement or stimulation of different body parts and to stimulation of corresponding cortical regions. Experimental evidence suggests that the BG are organized somatotopically, i.e., specific areas of the body are associated with specific regions in the BG nuclei. Signals related to the same body part that propagate along different pathways converge onto the same BG neurons, leading to characteristic shapes of cortically evoked responses. This suggests the existence of functional channels that allow for the processing of different motor commands or information related to different body parts in parallel. Neurological disorders such as Parkinson's disease are associated with pathological activity in the BG and impaired synaptic connectivity, together with reorganization of somatotopic maps. One hypothesis is that motor symptoms are, at least partly, caused by an impairment of network structure perturbing the organization of functional channels.MethodsWe developed a computational model of the STN-GPe circuit, a central part of the BG. By removing individual synaptic connections, we analyzed the contribution of signals propagating along different pathways to cortically evoked responses. We studied how evoked responses are affected by systematic changes in the network structure. To quantify the BG's organization in the form of functional channels, we suggested a two-site stimulation protocol.ResultsOur model reproduced the cortically evoked responses of STN and GPe neurons and the contributions of different pathways suggested by experimental studies. Cortical stimulation evokes spatio-temporal response patterns that are linked to the underlying synaptic network structure. Our two-site stimulation protocol yielded an approximate functional channel width.Discussion/conclusionThe presented results provide insight into the organization of BG synaptic connectivity, which is important for the development of computational models. The synaptic network structure strongly affects the processing of cortical signals and may impact the generation of pathological rhythms. Our work may motivate further experiments to analyze the network structure of BG nuclei and their organization in functional channels.
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spelling doaj.art-2a9c847358204a1aa49a93d4cd4915e72023-08-22T07:55:42ZengFrontiers Media S.A.Frontiers in Neuroinformatics1662-51962023-08-011710.3389/fninf.2023.12177861217786Synaptic network structure shapes cortically evoked spatio-temporal responses of STN and GPe neurons in a computational modelJustus A. Kromer0Hemant Bokil1Peter A. Tass2Department of Neurosurgery, Stanford University, Stanford, CA, United StatesBoston Scientific Neuromodulation, Valencia, CA, United StatesDepartment of Neurosurgery, Stanford University, Stanford, CA, United StatesIntroductionThe basal ganglia (BG) are involved in motor control and play an essential role in movement disorders such as hemiballismus, dystonia, and Parkinson's disease. Neurons in the motor part of the BG respond to passive movement or stimulation of different body parts and to stimulation of corresponding cortical regions. Experimental evidence suggests that the BG are organized somatotopically, i.e., specific areas of the body are associated with specific regions in the BG nuclei. Signals related to the same body part that propagate along different pathways converge onto the same BG neurons, leading to characteristic shapes of cortically evoked responses. This suggests the existence of functional channels that allow for the processing of different motor commands or information related to different body parts in parallel. Neurological disorders such as Parkinson's disease are associated with pathological activity in the BG and impaired synaptic connectivity, together with reorganization of somatotopic maps. One hypothesis is that motor symptoms are, at least partly, caused by an impairment of network structure perturbing the organization of functional channels.MethodsWe developed a computational model of the STN-GPe circuit, a central part of the BG. By removing individual synaptic connections, we analyzed the contribution of signals propagating along different pathways to cortically evoked responses. We studied how evoked responses are affected by systematic changes in the network structure. To quantify the BG's organization in the form of functional channels, we suggested a two-site stimulation protocol.ResultsOur model reproduced the cortically evoked responses of STN and GPe neurons and the contributions of different pathways suggested by experimental studies. Cortical stimulation evokes spatio-temporal response patterns that are linked to the underlying synaptic network structure. Our two-site stimulation protocol yielded an approximate functional channel width.Discussion/conclusionThe presented results provide insight into the organization of BG synaptic connectivity, which is important for the development of computational models. The synaptic network structure strongly affects the processing of cortical signals and may impact the generation of pathological rhythms. Our work may motivate further experiments to analyze the network structure of BG nuclei and their organization in functional channels.https://www.frontiersin.org/articles/10.3389/fninf.2023.1217786/fullbasal gangliaevoked responsesfunctional channelsnetwork connectivitymultichannel stimulationneural networks
spellingShingle Justus A. Kromer
Hemant Bokil
Peter A. Tass
Synaptic network structure shapes cortically evoked spatio-temporal responses of STN and GPe neurons in a computational model
Frontiers in Neuroinformatics
basal ganglia
evoked responses
functional channels
network connectivity
multichannel stimulation
neural networks
title Synaptic network structure shapes cortically evoked spatio-temporal responses of STN and GPe neurons in a computational model
title_full Synaptic network structure shapes cortically evoked spatio-temporal responses of STN and GPe neurons in a computational model
title_fullStr Synaptic network structure shapes cortically evoked spatio-temporal responses of STN and GPe neurons in a computational model
title_full_unstemmed Synaptic network structure shapes cortically evoked spatio-temporal responses of STN and GPe neurons in a computational model
title_short Synaptic network structure shapes cortically evoked spatio-temporal responses of STN and GPe neurons in a computational model
title_sort synaptic network structure shapes cortically evoked spatio temporal responses of stn and gpe neurons in a computational model
topic basal ganglia
evoked responses
functional channels
network connectivity
multichannel stimulation
neural networks
url https://www.frontiersin.org/articles/10.3389/fninf.2023.1217786/full
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AT hemantbokil synapticnetworkstructureshapescorticallyevokedspatiotemporalresponsesofstnandgpeneuronsinacomputationalmodel
AT peteratass synapticnetworkstructureshapescorticallyevokedspatiotemporalresponsesofstnandgpeneuronsinacomputationalmodel