{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,13]],"date-time":"2026-05-13T05:04:19Z","timestamp":1778648659659,"version":"3.51.4"},"reference-count":33,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2021,10,4]],"date-time":"2021-10-04T00:00:00Z","timestamp":1633305600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001691","name":"Japan Society for the Promotion of Science","doi-asserted-by":"publisher","award":["17K17908"],"award-info":[{"award-number":["17K17908"]}],"id":[{"id":"10.13039\/501100001691","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001691","name":"Japan Society for the Promotion of Science","doi-asserted-by":"publisher","award":["20K19448"],"award-info":[{"award-number":["20K19448"]}],"id":[{"id":"10.13039\/501100001691","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001691","name":"Japan Society for the Promotion of Science","doi-asserted-by":"publisher","award":["1082626"],"award-info":[{"award-number":["1082626"]}],"id":[{"id":"10.13039\/501100001691","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004329","name":"Javna Agencija za Raziskovalno Dejavnost RS","doi-asserted-by":"publisher","award":["J2-1731"],"award-info":[{"award-number":["J2-1731"]}],"id":[{"id":"10.13039\/501100004329","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004329","name":"Javna Agencija za Raziskovalno Dejavnost RS","doi-asserted-by":"publisher","award":["L7-9421"],"award-info":[{"award-number":["L7-9421"]}],"id":[{"id":"10.13039\/501100004329","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004329","name":"Javna Agencija za Raziskovalno Dejavnost RS","doi-asserted-by":"publisher","award":["P2-0041"],"award-info":[{"award-number":["P2-0041"]}],"id":[{"id":"10.13039\/501100004329","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The relationship between motor unit (MU) firing behavior and the severity of neurodegeneration in Parkinson\u2019s disease (PD) is not clear. This study aimed to elucidate the association between degeneration with dopaminergic pathways and MU firing behavior in people with PD. Fourteen females with PD (age, 72.6 \u00b1 7.2 years, disease duration, 3.5 \u00b1 2.1 years) were enrolled in this study. All participants performed a submaximal, isometric knee extension ramp-up contraction from 0% to 80% of their maximal voluntary contraction strength. We used high-density surface electromyography with 64 electrodes to record the muscle activity of the vastus lateralis muscle and decomposed the signals with the convolution kernel compensation technique to extract the signals of individual MUs. We calculated the degree of degeneration of the central lesion-specific binding ratio by dopamine transporter single-photon emission computed tomography. The primary, novel results were as follows: (1) moderate-to-strong correlations were observed between the degree of degeneration of the central lesion and MU firing behavior; (2) a moderate correlation was observed between clinical measures of disease severity and MU firing behavior; and (3) the methods of predicting central nervous system degeneration from MU firing behavior abnormalities had a high detection accuracy with an area under the curve &gt;0.83. These findings suggest that abnormalities in MU activity can be used to predict central nervous system degeneration following PD.<\/jats:p>","DOI":"10.3390\/s21196615","type":"journal-article","created":{"date-parts":[[2021,10,10]],"date-time":"2021-10-10T21:37:49Z","timestamp":1633901869000},"page":"6615","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Association between the Degree of Pre-Synaptic Dopaminergic Pathway Degeneration and Motor Unit Firing Behavior in Parkinson\u2019s Disease Patients"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0088-8447","authenticated-orcid":false,"given":"Yuichi","family":"Nishikawa","sequence":"first","affiliation":[{"name":"Faculty of Frontier Engineering, Institute of Science & Engineering, Kanazawa University, Kanazawa 920-1192, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8918-5181","authenticated-orcid":false,"given":"Kohei","family":"Watanabe","sequence":"additional","affiliation":[{"name":"Laboratory of Neuromuscular Biomechanics, School of Health and Sport Sciences, Chukyo University, Toyota 470-0393, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8338-5978","authenticated-orcid":false,"given":"Ale\u0161","family":"Holobar","sequence":"additional","affiliation":[{"name":"Faculty of Electrical Engineering and Computer Science, University of Maribor, 2000 Maribor, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tetsuya","family":"Takahashi","sequence":"additional","affiliation":[{"name":"Department of Rehabilitation, Faculty of Rehabilitation, Hiroshima International University, Higashihiroshima 739-2695, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4447-8917","authenticated-orcid":false,"given":"Noriaki","family":"Maeda","sequence":"additional","affiliation":[{"name":"Division of Sports Rehabilitation, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima 734-8553, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hirofumi","family":"Maruyama","sequence":"additional","affiliation":[{"name":"Department of Clinical Neuroscience and Therapeutics, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima 734-8551, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shinobu","family":"Tanaka","sequence":"additional","affiliation":[{"name":"Faculty of Frontier Engineering, Institute of Science & Engineering, Kanazawa University, Kanazawa 920-1192, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Allison S","family":"Hyngstrom","sequence":"additional","affiliation":[{"name":"Department of Physical Therapy, Marquette University, Milwaukee, WI 53201, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,10,4]]},"reference":[{"key":"ref_1","first-page":"S21","article-title":"Prevalence of Parkinson\u2019s disease in Europe: A collaborative study of population-based cohorts. 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