{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,25]],"date-time":"2026-04-25T04:54:23Z","timestamp":1777092863944,"version":"3.51.4"},"reference-count":47,"publisher":"AIP Publishing","issue":"6","funder":[{"DOI":"10.13039\/501100004329","name":"The Slovenian Research and Innovation Agency","doi-asserted-by":"publisher","award":["P1-0403"],"award-info":[{"award-number":["P1-0403"]}],"id":[{"id":"10.13039\/501100004329","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["pubs.aip.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2025,6,1]]},"abstract":"<jats:p>Fractal Dimension (FD), a measure of signal complexity, offers unique insights into nonlinear brain dynamics in neurodegenerative disorders. While Electroencephalography (EEG)-based biomarkers for Parkinson\u2019s disease (PD) are emerging, the fractal properties of PD-related neural activity remain underexplored. Here, we introduce FD as a novel nonlinear biomarker to distinguish PD patients (n=74) from healthy controls (n=37) during interval-timing tasks (3\/7\u2009s durations). EEG recordings revealed significantly higher FD values in PD patients during response phases, particularly in frontotemporal, parietal, and motor regions, indicating disrupted neural adaptability. Our findings reveal that short intervals engaged sensorimotor areas, while long intervals implicated frontoparietal networks, which uncovered task-specific effects. These findings highlight FD\u2019s sensitivity to PD-related neural disorganization, offering a robust diagnostic tool for capturing disease-specific complexity changes. This study establishes FD as the first EEG-derived fractal biomarker for PD, advancing our understanding of its neurophysiological mechanisms.<\/jats:p>","DOI":"10.1063\/5.0274411","type":"journal-article","created":{"date-parts":[[2025,6,2]],"date-time":"2025-06-02T14:21:37Z","timestamp":1748874097000},"update-policy":"https:\/\/doi.org\/10.1063\/aip-crossmark-policy-page","source":"Crossref","is-referenced-by-count":10,"title":["Elevated EEG fractal dimension in Parkinson\u2019s during timing tasks"],"prefix":"10.1063","volume":"35","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3184-0582","authenticated-orcid":false,"given":"Raheleh","family":"Davoodi","sequence":"first","affiliation":[{"name":"Faculty of Electrical Engineering, Shahid Beheshti University 1 , Tehran,","place":["Iran"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0336-6553","authenticated-orcid":false,"given":"Mahtab","family":"Mehrabbeik","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, Amirkabir University of Technology (Tehran Polytechnic) 2 , Tehran,","place":["Iran"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6845-7539","authenticated-orcid":false,"given":"Sajad","family":"Jafari","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, Amirkabir University of Technology (Tehran Polytechnic) 2 , Tehran,","place":["Iran"]},{"name":"Center for Research, SRM Easwari Engineering College, Chennai 3 ,","place":["India"]},{"name":"Center for Cognitive Science, Trichy SRM Medical College Hospital and Research Center, Trichy 4 ,","place":["India"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3087-541X","authenticated-orcid":false,"given":"Matja\u017e","family":"Perc","sequence":"additional","affiliation":[{"name":"Faculty of Natural Sciences and Mathematics, University of Maribor 5 , 2000 Maribor,","place":["Slovenia"]},{"name":"Community Healthcare Center Dr. Adolf Drolc Maribor 6 , 2000 Maribor,","place":["Slovenia"]},{"name":"University College, Korea University 7 , 02841 Seoul,","place":["Republic of Korea"]},{"name":"Department of Physics, Kyung Hee University 8 , Seoul 02447,","place":["Republic of Korea"]}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"317","published-online":{"date-parts":[[2025,6,2]]},"reference":[{"key":"2025060210213153800_c1","doi-asserted-by":"publisher","first-page":"S24","DOI":"10.21037\/apm.2019.10.01","article-title":"Patient and caregiver characteristics associated with caregiver burden in Parkinson\u2019s disease: A palliative care approach","volume":"9","year":"2020","journal-title":"Ann. 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