Psilocybin’s Kinematic Effect on Manual Dexterity

Psilocybin’s Kinematic Effect on Manual Dexterity | 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 Research Article Psilocybin’s Kinematic Effect on Manual Dexterity Pierre Klintefors, Chiranth Bhagavan, Richard Kanaan, Alexander Bryson, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9291780/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 Rationale Clinical interest in psilocybin-assisted rehabilitation for motor disorders is growing. However, psilocybin’s motor effects are under-researched, and quantifying them is essential for assessing treatment risks and outcomes. Objectives This study aims to clarify whether acute effects of psilocybin disrupts established patterns of manual dexterity and coordination. Specifically, we evaluate the impact of psilocybin on velocity, smoothness and kinematic synergies. Methods In a randomised, blinded trial, healthy participants received three doses of psilo-cybin (5–20 mg) administered one week apart. Manual dexterity was assessed using the Box and Block Test (BBT) at baseline and 1.5, 3, and 4.5 hours post-drug administration. Task performance was analysed using a Bayesian mixed-effects model. For kinematic analysis, 21 hand landmarks were tracked from video recordings obtained at baseline and 1.5 hours post-administration. Principal component analysis (PCA) was the basis for evaluating the stability and dimensionality of kinematic synergies. Results BBT performance showed a modest biphasic dose–response pattern at higher doses (10–20 mg), with slight impairment during peak effects and slight improvement 4.5 hours post-administration relative to baseline. Effect sizes were small compared to inter-individual baseline variability. Kinematic analyses revealed no substantial changes in movement smoothness or velocity. Dimensionality metrics indicated a stable coordination structure, although finger movements showed a subtle increase in complexity. Conclusions Low to moderate doses of psilocybin did not meaningfully disrupt manual dexterity or the latent structure of hand coordination. These findings support the feasibility of combining psilocybin administration with active motor rehabilitation. Trial Registration: Australian New Zealand Clinical Trials Registry: ACTRN12621000560897 Date registered: 12 May 2021 URL: https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id= 381526&isReview=true Psilocybin Psilocin Motor Function Box and Block Test PCA Kinematic Synergies Manual Dexterity Motor Control Full Text Additional Declarations No competing interests reported. Supplementary Files CONSORTDiagram.jpg 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. 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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-9291780","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":621800068,"identity":"e7edec75-57c4-4e9b-819a-8b109f4d42ce","order_by":0,"name":"Pierre 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Motor Control","lastPublishedDoi":"10.21203/rs.3.rs-9291780/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9291780/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"Rationale Clinical interest in psilocybin-assisted rehabilitation for motor disorders is growing. However, psilocybin’s motor effects are under-researched, and quantifying them is essential for assessing treatment risks and outcomes. Objectives This study aims to clarify whether acute effects of psilocybin disrupts established patterns of manual dexterity and coordination. Specifically, we evaluate the impact of psilocybin on velocity, smoothness and kinematic synergies. Methods In a randomised, blinded trial, healthy participants received three doses of psilo-cybin (5–20 mg) administered one week apart. Manual dexterity was assessed using the Box and Block Test (BBT) at baseline and 1.5, 3, and 4.5 hours post-drug administration. Task performance was analysed using a Bayesian mixed-effects model. For kinematic analysis, 21 hand landmarks were tracked from video recordings obtained at baseline and 1.5 hours post-administration. Principal component analysis (PCA) was the basis for evaluating the stability and dimensionality of kinematic synergies. Results BBT performance showed a modest biphasic dose–response pattern at higher doses (10–20 mg), with slight impairment during peak effects and slight improvement 4.5 hours post-administration relative to baseline. Effect sizes were small compared to inter-individual baseline variability. Kinematic analyses revealed no substantial changes in movement smoothness or velocity. Dimensionality metrics indicated a stable coordination structure, although finger movements showed a subtle increase in complexity. Conclusions Low to moderate doses of psilocybin did not meaningfully disrupt manual dexterity or the latent structure of hand coordination. These findings support the feasibility of combining psilocybin administration with active motor rehabilitation. 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