Autistic and nonautistic adolescents do not differ in adaptation to gaze direction

Predictive processing accounts of autism posit that autistic individuals' perception is less biased by expectations than nonautistic individuals', perhaps through stronger precision-weighting of prediction errors. Since precision-weighting is fundamental to all information processing, under this theory, the differences between autistic and nonautistic individuals should be domain-general and observable in both behavior and brain responses. This study used EEG, behavioral responses, and eye-tracking co-registration during gaze-direction adaptation, to investigate whether increased precision-weighting of prediction errors is evident through smaller adaptation after-effects in autistic adolescents compared with nonautistic peers. Multilevel modeling showed that autistic and nonautistic adolescents' responses were consistent with behavioral adaptation, with Bayesian statistics providing extremely strong evidence for the absence of a group difference. Cluster-based permutation testing of ERP responses did not show the expected adaptation after-effect but did show habituation to repeated stimulus presentation, and no group difference was detected, a result not consistent with the theoretical account. Combined with the few other available studies, the current findings raise challenges for the theory, suggesting no fundamental difference in precision-weighting of prediction errors in autism. Some researchers claim that we never see the world exactly as it is, but instead we always interpret things based on what we have seen before. Recently, some researchers have tried to explain autism as the result of differences in this system of interpreting the world based on what we have seen before. This experiment used a visual illusion to test this idea, because the strength of the illusion can show us how much participants are interpreting pictures based on what they have seen before. We used this illusion to test whether autistic teenagers were influenced less by the previous pictures we had showed them than nonautistic teenagers were. We found very strong evidence that the autistic and nonautistic teenagers were equally influenced by what they had seen before, which does not support the theory, and we ask for updates to the theory.