Spatio-temporal processing of tactile stimuli in autistic children

TLDR

Autism is associated with altered multisensory integration, yet the spatio‑temporal processing of tactile stimuli, such as the crossed‑hand temporal‑order illusion, remains poorly understood. We investigated the crossed‑hands illusion in autistic children. Autistic children exhibited a markedly reduced crossed‑hand temporal‑order illusion, with higher AQ scores linked to an even smaller deficit, indicating that while basic spatio‑temporal tactile processing is present, it is altered compared to neurotypical peers.

Abstract

Abstract Altered multisensory integration has been reported in autism; however, little is known concerning how the autistic brain processes spatio-temporal information concerning tactile stimuli. We report a study in which a crossed-hands illusion was investigated in autistic children. Neurotypical individuals often experience a subjective reversal of temporal order judgments when their hands are stimulated while crossed and the illusion is known to be acquired in early childhood. However, under those conditions where the somatotopic representation is given priority over the actual spatial location of the hands, such reversals may not occur. Here, we showed that a significantly smaller illusory reversal was demonstrated in autistic children than in neurotypical children. Furthermore, in an additional experiment, the young boys who had higher Autism Spectrum Quotient (AQ) scores generally showed a smaller crossed hands deficit. These results suggest that rudimentary spatio-temporal processing of tactile stimuli exists in autistic children and the altered processing may interfere with the development of an external frame of reference in real-life situations.