{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T06:56:01Z","timestamp":1790751361190,"version":"4.1.0"},"reference-count":61,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T00:00:00Z","timestamp":1790726400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Hum. Neurosci."],"abstract":"<jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>In motor tasks with repetitive trials, motor vigor varies substantially from trial to trial in people with Parkinson's disease (PD). A key question is whether neural variability reflects behavioral variability or whether additional variability emerges as the neural signal is translated into movement. We aimed to identify a vigor-related neural network that could provide a candidate target for brain stimulation.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We analyzed individual-trial fMRI data from 18 participants with PD who performed an overlearned ballistic hand-squeeze task in OFF- and ON-medication sessions while receiving subthreshold galvanic vestibular stimulation (GVS) with different stimulus waveforms. Single-trial fMRI responses were estimated using GLMsingle and entered into a constrained optimisation framework designed to identify a network that was task-active, encoded behavior, showed low trial-to-trial variability, and was spatially coherent.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>The analysis identified a distributed vigor network whose activity remained related to behavioral vigor while showing lower variability than behavior itself. The network included motor, striatal, cerebellar, thalamic, parietal, temporal-limbic, and orbitofrontal regions and showed limited overlap with the standard task-activation map. GVS waveforms associated with faster responses were accompanied by corresponding changes in vigor-network activity, but not in the broader task-activation network. Dopaminergic medication was also associated with stronger local functional connectivity within the vigor network.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Discussion<\/jats:title>\n                    <jats:p>These findings suggest that movement variability in PD may arise partly when a relatively stable central vigor-related command is translated downstream into movement. The identified network may therefore provide a potential target for neuromodulation approaches aimed at increasing motor vigor in people with PD. Independent validation and future causal testing are needed.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fnhum.2026.1928519","type":"journal-article","created":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T06:03:40Z","timestamp":1790748220000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["A consistent vigor network in Parkinson's disease: a potential target for brain stimulation effects"],"prefix":"10.3389","volume":"20","author":[{"given":"Zahra","family":"Kavian","sequence":"first","affiliation":[{"name":"Pacific Parkinson's Research Center, Djavad Mowafaghian Center for Brain Health, University of British Columbia","place":["Vancouver, BC, Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sepideh","family":"Hajipour Sardouie","sequence":"additional","affiliation":[{"name":"Pacific Parkinson's Research Center, Djavad Mowafaghian Center for Brain Health, University of British Columbia","place":["Vancouver, BC, Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Emad","family":"Arasteh","sequence":"additional","affiliation":[{"name":"Pacific Parkinson's Research Center, Djavad Mowafaghian Center for Brain Health, University of British Columbia","place":["Vancouver, BC, Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maryam S.","family":"Mirian","sequence":"additional","affiliation":[{"name":"Pacific Parkinson's Research Center, Djavad Mowafaghian Center for Brain Health, University of British Columbia","place":["Vancouver, BC, Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Varsha","family":"Sreenivasan","sequence":"additional","affiliation":[{"name":"Pacific Parkinson's Research Center, Djavad Mowafaghian Center for Brain Health, University of British Columbia","place":["Vancouver, BC, Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Milad","family":"Yazdani","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, University of British Columbia","place":["Vancouver, BC, Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Martin J.","family":"McKeown","sequence":"additional","affiliation":[{"name":"Pacific Parkinson's Research Center, Djavad Mowafaghian Center for Brain Health, University of British Columbia","place":["Vancouver, BC, Canada"]},{"name":"Faculty of Medicine (Neurology), University of British Columbia","place":["Vancouver, BC, Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,9,30]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1007\/s00221-012-3226-1","article-title":"Electrocorticographic (ECoG) correlates of human arm movements","volume":"223","author":"Anderson","year":"2012","journal-title":"Exp. 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