Contactless optical decoding of cortical language responses via region-transferable speckle dynamics

Contactless optical decoding of cortical language responses via region-transferable speckle dynamics | 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 Contactless optical decoding of cortical language responses via region-transferable speckle dynamics Natalya Segal, Moshe Bar, Daniel Rubinstein, Yehor Krapovnytskyi, and 4 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9141990/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 Remote decoding of human brain activity without surgery or physical contact remains a major challenge for brain-computer interfaces. Using laser speckle dynamics, we show that cortical responses during language processing can be decoded contactlessly. Across two independent experimental paradigms involving 17 healthy participants, 23 sessions, and 462 recordings, a classifier distinguished responses to intelligible versus incomprehensible speech in Wernicke’s area with a mean accuracy of 95.69% and an AUC of 0.98, using 40-ms input segments and requiring less than 1 minute of calibration (20s of labelled data per category). Importantly, the decoding representations were derived from a self-supervised model trained on a different task, inner speech, and from a different cortical region, Broca’s area, demonstrating transfer across both language tasks and anatomically distinct cortical areas. These findings support the feasibility of contactless optical decoding of cortical language responses and indicate that speckle-derived representations of cortical hemodynamics capture response structure that generalizes across regions, substantially reducing calibration requirements and providing a foundation for practical contactless cortical decoding. Biological sciences/Biological techniques/Software Biological sciences/Computational biology and bioinformatics/Computational neuroscience/Neural decoding Biological sciences/Computational biology and bioinformatics/Machine learning Biological sciences/Neuroscience/Computational neuroscience/Neural decoding Biological sciences/Neuroscience/Computational neuroscience/Learning algorithms Full Text Additional Declarations There is NO Competing Interest. 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. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-9141990","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":609653142,"identity":"d34b1f38-eabc-4f99-aa71-ec13de1a59e4","order_by":0,"name":"Natalya 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