Autism is a developmental disorder characterized by impaired social skills and accompanied by motor and perceptual atypicalities. Its etiology is an open question, partly due to the diverse range of associated difficulties. Based on recent observations that individuals with autism are slow in updating perceptual priors, we now hypothesized that motor updating is also slow. Slow motor updating is expected to hamper the ability to synchronize to external events, since asynchronies are corrected sluggishly. Since sensorimotor synchronization is important for social bonding and cooperation, its impairment is expected to impair social skills. To test this hypothesis, we measured paced finger tapping to a metronome in neurotypical, ASD, and dyslexia groups. Dyslexia was assessed as a control group with a non-social neurodevelopmental atypicality. Only the ASD group showed reduced sensorimotor synchronization. Trial-by-trial computational modelling revealed that their ability to form controlled motor responses and to maintain reliable temporal representations was adequate. Only their rate of error-correction was slow and was correlated with the severity of their social difficulties. Taken together, these findings suggest that slow updating in autism contributes to both sloppy sensorimotor performance and difficulties in forming social bonds.
bioRxiv Subject Collection: Neuroscience