Atypical Interpersonal Motor Synchrony and Intrapersonal Movement Variability in Autism: Pose Estimation Analysis of Free-play

Atypical Interpersonal Motor Synchrony and Intrapersonal Movement Variability in Autism: Pose Estimation Analysis of Free-play | 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 Atypical Interpersonal Motor Synchrony and Intrapersonal Movement Variability in Autism: Pose Estimation Analysis of Free-play Sara Akhavan, Nada Kojovic, Julie Segers, Thomas Maillart, Marie Schaer This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7435901/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 Socio-motor behaviours, like interpersonal motor synchrony (IMS), are widely thought to be atypical in autism, yet they remain poorly defined, mechanistically unclear, and difficult to detect by eye. Studies exploring IMS have predominantly required participants to be stationary, making them ill-suited to observing the diverse behaviours and phenotypes associated with autism, especially in young children and naturalistic settings. We analysed 60 autistic and 27 typically developing young children aged 1 - 4 years during free-play segments of ADOS-2 diagnostic sessions. To measure IMS between child-assessor dyads, we applied 2-D pose estimation technology, OpenPose, and dynamic time warping (DTW). Our results show that child-assessor dyads with autistic children exhibited lower IMS than controls did in both trunk regions and head regions. Autistic children also demonstrated higher levels of intrapersonal movement variability (IMV). IMS and IMV were negatively correlated, which is a novel observation. Both lower IMS and higher IMV in autistic children were associated with higher levels of autistic traits, lower cognitive functioning skills, and lower adaptive functioning skills. Our findings highlight the potential of pose estimation and DTW to reliably detect atypical IMS and IMV in autistic children. Combined, these methods show promise as early behavioural markers, bringing us closer to non-invasive, digital tools for precise autism phenotyping in naturalistic settings. Biological sciences/Neuroscience Biological sciences/Psychology Social science/Psychology Full Text Additional Declarations No competing interests reported. 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-7435901","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":504985449,"identity":"cacbd19b-a8b7-4699-9ce4-b0d4247e259f","order_by":0,"name":"Sara Akhavan","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABHklEQVRIiWNgGAWjYHCDBGZmMM3eAGSDGBJEa+E5QLIWiQSoAA4t8u1nH35g+GOT2M+e/Ni4oOawvLnkG7MHD37ZMPDPbsCqxeBMurEEY1ta4syeZ8bJM44dNtw5O8fcILEvjUHizgHsWhiAcowNhxM33EgwPszDlsa44XaOmURiz2EGA7gL0RzW/4z5B8Of/4n7b6R/PszzL81+w80zIC3/cWphuJHGJsHAdiBxg0SOcTJvmw3QOh4ziYQfB3BqMbjxjM0isS3ZeMaZN8XGvH02yRvOpJVJJDYk80jcwOWwNOYbH/7Yyfa3p2+W5vkmYbvh+OFtkj/+2Mnxz8DhMBAASjk2oIgwtjHw4FYPAfZo/D+ENIyCUTAKRsEIAgAtcWFs5cYUiQAAAABJRU5ErkJggg==","orcid":"","institution":"University of Geneva","correspondingAuthor":true,"prefix":"","firstName":"Sara","middleName":"","lastName":"Akhavan","suffix":""},{"id":504985450,"identity":"200c1710-7956-4cf9-a83d-3e20345a61ef","order_by":1,"name":"Nada Kojovic","email":"","orcid":"","institution":"University of Geneva","correspondingAuthor":false,"prefix":"","firstName":"Nada","middleName":"","lastName":"Kojovic","suffix":""},{"id":504985451,"identity":"e75a53a6-5d87-44b6-a5bf-76af2608e3fa","order_by":2,"name":"Julie Segers","email":"","orcid":"","institution":"University of Antwerp","correspondingAuthor":false,"prefix":"","firstName":"Julie","middleName":"","lastName":"Segers","suffix":""},{"id":504985452,"identity":"00290793-8165-4066-856e-e6ae67ceec31","order_by":3,"name":"Thomas Maillart","email":"","orcid":"","institution":"University of Geneva","correspondingAuthor":false,"prefix":"","firstName":"Thomas","middleName":"","lastName":"Maillart","suffix":""},{"id":504985453,"identity":"f3e5d6ad-3ad8-48ae-9d5b-7da85777809c","order_by":4,"name":"Marie Schaer","email":"","orcid":"","institution":"University of Geneva","correspondingAuthor":false,"prefix":"","firstName":"Marie","middleName":"","lastName":"Schaer","suffix":""}],"badges":[],"createdAt":"2025-08-22 15:38:14","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7435901/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7435901/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":90870552,"identity":"73b27346-24c1-49bc-a141-c3f864c50834","added_by":"auto","created_at":"2025-09-09 08:08:49","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":4957217,"visible":true,"origin":"","legend":"","description":"","filename":"Akhavanetal2025forsubmission.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7435901/v1_covered_a8d03560-0046-4a84-b36e-6d835d35f421.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Atypical Interpersonal Motor Synchrony and Intrapersonal Movement Variability in Autism: Pose Estimation Analysis of Free-play","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-7435901/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7435901/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"Socio-motor behaviours, like interpersonal motor synchrony (IMS), are widely thought to be atypical in autism, yet they remain poorly defined, mechanistically unclear, and difficult to detect by eye. \nStudies exploring IMS have predominantly required participants to be stationary, making them ill-suited to observing the diverse behaviours and phenotypes associated with autism, especially in young children and naturalistic settings. 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