Neurophysiological Fluctuation Detects Mental Fatigue Prior to Subjective Awareness

Neurophysiological Fluctuation Detects Mental Fatigue Prior to Subjective Awareness | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Neurophysiological Fluctuation Detects Mental Fatigue Prior to Subjective Awareness Kaniska Samanta, KongFatt Wong-Lin, Girijesh Prasad, Saugat Bhattacharyya This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7358429/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Objective and timely detection of mental fatigue is critical to its understanding and intervention. However, previous studies did not clearly dissociate mental fatigue from other arousal states. Here, we propose an adaptive, cognitively demanding memory recall task to induce mental fatigue, taking into account individual variability while maintaining task engagement. We found a decrease in pupil size and response speed, and enhanced frontal and frontotemporal beta- and gamma-band power of electroencephalography (EEG) after mental fatigue induction, while maintaining a constant level of boredom and motivation. Crucially, we found increased gamma-band power fluctuation, regardless of task difficulty, to robustly detect mental fatigue minutes before self-reported indication. We also found EEG's hyperconnectivity, and its enhanced fluctuation to align with our arousal-cortical model prediction. Overall, this study lays the foundation for effective assessment of mental fatigue and its impacts on cognition. Biological sciences/Neuroscience/Cognitive neuroscience/Motivation Biological sciences/Biological techniques/Electrophysiology/Electroencephalography – EEG Mental fatigue brain-computer interface BCI electroencephalography EEG adaptive cognitive task paradigm psychomotor vigilance mathematical model machine learning Full Text Additional Declarations There is NO Competing Interest. Supplementary Files Samanta2025MentalFatigueEEGNHBSupplementaryInformation.pdf Neurophysiological Fluctuation Detects Mental Fatigue Prior to Subjective Awareness - Supplementary Information Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7358429","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":500209517,"identity":"55b6366b-4271-4368-86a5-8c119b7e643f","order_by":0,"name":"Kaniska Samanta","email":"","orcid":"https://orcid.org/0000-0002-2806-9881","institution":"Ulster University","correspondingAuthor":false,"prefix":"","firstName":"Kaniska","middleName":"","lastName":"Samanta","suffix":""},{"id":500209518,"identity":"346224f6-da67-4bec-a9a5-20c8d291e4fb","order_by":1,"name":"KongFatt Wong-Lin","email":"","orcid":"https://orcid.org/0000-0001-8724-4398","institution":"Intelligent Systems Research Centre, Ulster University, Magee Campus, Derry~Londonderry, Northern Ireland, UK","correspondingAuthor":false,"prefix":"","firstName":"KongFatt","middleName":"","lastName":"Wong-Lin","suffix":""},{"id":500209519,"identity":"14a85d72-017c-4ebc-a63d-a29c32979e1a","order_by":2,"name":"Girijesh Prasad","email":"","orcid":"https://orcid.org/0000-0003-3284-9589","institution":"Ulster University","correspondingAuthor":false,"prefix":"","firstName":"Girijesh","middleName":"","lastName":"Prasad","suffix":""},{"id":500209516,"identity":"056b55db-e3bb-4283-9016-e80b8daa0ad2","order_by":3,"name":"Saugat Bhattacharyya","email":"data:image/png;base64,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","orcid":"https://orcid.org/0000-0001-9191-3670","institution":"Ulster University","correspondingAuthor":true,"prefix":"","firstName":"Saugat","middleName":"","lastName":"Bhattacharyya","suffix":""}],"badges":[],"createdAt":"2025-08-12 18:10:07","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7358429/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7358429/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":89840171,"identity":"3fda6fbd-5072-4006-be79-19fc61ef073e","added_by":"auto","created_at":"2025-08-25 15:12:50","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":5696121,"visible":true,"origin":"","legend":"Article File","description":"","filename":"Samanta2025MentalFatigueEEGNHBManuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7358429/v1_covered_de7ee2b1-65fa-4ef0-97cc-70fa8f5935d4.pdf"},{"id":89250165,"identity":"18042c37-8773-4bc5-a35a-782c0efc0672","added_by":"auto","created_at":"2025-08-18 03:22:09","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":9252228,"visible":true,"origin":"","legend":"Neurophysiological Fluctuation Detects Mental Fatigue Prior to Subjective Awareness - 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