[PS-1.21] Aberrant Statistical Learning Impairs Sensorimotor Synchronization in Autism Spectrum Disorders

Vishne, G. 1 , Jacoby, N. 2 , Frenkel, O. 1 & Ahissar, M. 1

1 Hebrew University of Jerusalem
2 Columbia University

Autism is characterized by deficits in social communication and repetitive patterns of behavior and actions. Much attention has been put on the social aspect of the disorder, but recently there is growing understanding that atypical sensory processing and motor deficits are core to the disorder. Several studies have identified impaired sensorimotor synchronization in individuals with autism, but the underlying cause remained elusive. We addressed this question by testing 30 individuals with autism and 47 neurotypical individuals on a finger-tapping task. In addition to blocks with fixed tempo, we used a novel manipulation of the external tempo to assess how individuals with autism learn environmental changes. There was substantially higher variability between taps in the autism group (p=0.006, W=1571). Using computational modelling we show that this impairment is the result of decreased use of recent stimuli for guiding behavior. Additionally, individuals with autism manifested reduced adaptation to changes in tempo (p=0.002, W=2036). Our novel analysis approach shows this stems from impaired mechanisms for fast correction, while long term learning of the new tempo is intact. Together these results show that individuals with autism are slow to learn environmental statistics, in line with behavioral reports of difficulties in the face of changes.