An overreliance on proprioceptive (intrinsic) sensory input from the body, compared to visual (extrinsic) input from the environment, may underpin core features of autism spectrum disorder (ASD). We developed an engaging videogame (HaptiKart) as a tool to examine differences in proprioceptive vs. visual bias in children and adults with ASD and whether bias correlates with age, core autism features, and intellectual ability. Eighty-one participants (33 ASD, 48 typically-developing, TD) aged 8 to 31 years played HaptiKart, a driving videogame with a force-feedback steering wheel that provided steering assist during gameplay. In separate trials, proprioceptive and visual feedback were selectively delayed, and differences in driving error between the conditions were used to calculate perceptual bias scores. Effects of autism diagnosis and age on perceptual (proprioceptive vs. visual) bias scores were examined, controlling for sex, as were associations of perceptual bias with autism symptom severity (ADOS-2, SRS-2), attention-deficit symptom severity (Conners4 ADHD Total Scores) ratings, and IQ (general ability index, GAI). The ASD group exhibited significantly higher proprioceptive bias than did the TD group (p=0.002). There was a trend for decreasing proprioceptive bias with age, but no significant diagnosis-by-age interaction. Increased proprioceptive bias correlated with higher autism severity and with lower IQ, but not ADHD symptoms. HaptiKart provides a highly scalable approach for measuring sensory-motor bias, revealing that individuals with ASD show elevated proprioceptive bias, correlating with autism severity. The HaptiKart sensory-motor bias measure may thereby serve as a digital biomarker for addressing autism heterogeneity in ways that can improve targeted intervention.

The authors declare that there are no conflicts of interest regarding the publication of this manuscript. However, we wish to disclose that we are in the process of trademarking the name of the videogame "HaptiKart." This project is part of our ongoing research efforts to assess sensory bias in children with autism. The authors believe that this potential trademark does not influence the objectivity of the research presented in this manuscript.

This research was supported by NIH/NIMH under Grants R21 MH127501 (PI: Eggebrecht) and R21 MH129899 (PI: Isik), and by NIH/NICHD under Grants P50 HD103538 (PI: Schlaggar) and the IDDRC R01 Project. Additional support came from the National Science Foundation (Grant 2124276, PI: Mostofsky), the Simons Foundation (Grant 724867, PI: Mostofsky), and The Eagles Autism Foundation (Grant WU-24-0499, PI: Eggebrecht).

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Ethics approval was received from the Johns Hopkins University School of Medicine Institutional Review Board before the study (IRB00269589).

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