Spatio-temporal processing of tactile stimuli in autistic children

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.

Investigating Visual–Tactile Interactions over Time and Space in Adults with Autism

“…Increased noise is believed to contribute to sensory symptomology in ASC (Pellicano 2013), for instance, vision may have an atypical effect on the experience, or expectation of being touched. Our findings also fit with the recent observation that tactile judgements are less affected in participants with ASC when the arms are crossed over the body midline (Wada et al 2014). This suggests that tactile spatial representations may be less affected by a visual frame-of-reference in ASC.…”

“…A recent study examining tactile temporal order judgements between the hands has indicated that children with ASC do not produce the typical performance detriment when their hands are crossed (Wada et al 2014). Although this is a purely tactile task, the hands crossed effect has been attributed to the visual frame of reference affecting tactile perception, which suggests that this multisensory effect may be atypical in ASC.…”

Salivary Oxytocin Concentration Associates with the Subjective Feeling of Body Ownership during the Rubber Hand Illusion

“…The result was partly consistent with previous studies reporting that individuals with ASD have disturbances in body representations (Cascio et al, 2012a; Paton et al, 2012; Palmer et al, 2015). Previous studies investigating motor learning (Haswell et al, 2009) and tactile temporal order judgment (Wada et al, 2014) suggested that the disturbances of body representations reported in individuals with ASD are explainable by a strong weight on proprioception. Interestingly, in the present study, we found that a subjective feeling of difficulty in social skills and communications (subscales of the AQ score) was strongly correlated with weak body ownership of the rubber hand.…”

Spatiotemporal processing of somatosensory stimuli in schizotypy

“…This is indeed the case in autistic children. They are characterized by greater reliance on proprioceptive information39, and show a significantly smaller crossed-hand effect than neurotypical children30. Hence, the greater reliance in proprioception of children with autism generates a bias in the weighting of anatomical and external spatial information during the TOJ crossed-hand task.…”

“…Moreover, to assess increases in the judgment reversals caused by the arm crossing manipulation, we computed the so-called sum of confusions ( SC ), defined as the sum of the differences between the response functions in the crossed and uncrossed conditions (respectively, P c and P u ) using the formula described in Wada and colleagues30, and reported in the Supplementary Materials. We also contrasted the differences between the response functions in the uncrossed and crossed conditions across the schizotypy groups.…”