In contatto con il Disturbo dello Spettro Autistico: comprendere il ruolo del Tocco Affettivo nell'ASD

Social interaction is a crucial and complex aspect of human behaviour that involves the cooperation of at least two individuals in a wide variety of contexts. It plays an important role in shaping people’s emotions, behaviour, and well-being, and includes various elements such as interpersonal distance, interoception and affective touch. Affective touch is essential in influencing people’s physical, social and emotional well-being, as it involves both sensory and socio-emotional factors. Social touch is therefore a multifaceted process, and tactile stimuli can be discriminative, involving the perceptual aspect of touch, or affective, involving both the perceptual and emotional experiences of touch. However, social interaction, particularly affective touch, can be impaired in conditions such as Autism Spectrum Disorder (ASD). ASD is characterised by impaired social communication, interaction, and stereotyped behaviour. Affective touch is a valuable area of investigation in ASD, as its complex nature provides insight into both sensory abnormalities and atypical socio-emotional behaviour. This study aimed to further the understanding of affective touch in ASD through the analysis of behavioural and physiological measures across a range of tasks. After completing four questionnaires (SIAS, STQ, AQ, BPQ), autistic and control participants underwent an interoception and an affective/discriminative touch task while their psychophysiological activity, namely electrodermal activity (EDA) and heart rate (BPM), was recorded. The results revealed behavioural peculiarities in ASD in comparison to controls and psychophysiological differences between the groups, highlighting the critical importance of affective touch. Specifically, at the explicit level, ASD subjects had difficulty distinguishing between the touch of a real hand and a fake hand, consistently reporting that they were touched by the real hand; at the implicit level, both ASD and control participants showed increased psychophysiological responses to affective touch compared to the discriminative stimulus. These findings can be explained using the predictive coding framework, specifically the High, Inflexible Precision of Prediction Errors in Autism (HIPPEA), which posits that individuals with ASD struggle to make precise and adaptive predictions about rapidly evolving social contexts. This study’s contribution to the predictive coding line of research advances our understanding of ASD social interaction.