Autonomic and hedonic response to affective touch in autism spectrum disorder.
Adults with autism show no skin-conductance reaction to pleasant touch yet call it unpleasant—so ask, don’t assume.
01Research in Context
What this study did
Capiotto et al. (2024) brought adults with autism and typical adults into a lab.
A researcher stroked each person’s forearm with a soft brush.
Sometimes the stroke was slow and gentle, the kind that usually feels nice.
Other times it was faster and neutral.
The team measured tiny sweat changes on the skin and asked, “How pleasant was that?”
What they found
Typical adults’ skin showed a small jump in sweat during the nice touch.
Adults with autism showed almost no skin change to either touch.
Yet the same adults with autism rated the nice touch as more unpleasant.
Their bodies stayed flat while their words said “I don’t like it.”
How this fits with other research
Bölte et al. (2008) saw a similar body-word split when they showed emotional pictures instead of touch.
Gadow et al. (2006) found typical skin reactions to pictures in autistic kids, but Francesca’s adults showed blunted reactions to touch.
The difference is age and stimulus: kids reacted to pictures, adults did not react to touch.
Kylliäinen et al. (2006) reported bigger skin spikes to eye contact in autistic kids, the opposite of the flat response seen here.
Together the papers map a shift: some social cues spike arousal early in life, while pleasant touch stays flat in adulthood.
Why it matters
If you use gentle touch to calm clients, check their reaction each time.
A flat sweat reading does not mean they feel neutral; they may feel discomfort they cannot easily name.
Pair touch trials with simple rating cards or icons so clients can show “I like it” or “stop.”
Consider alternate sensory tools such as deep pressure or weighted items that may bypass the unpleasant-light-touch response.
Want CEUs on This Topic?
The ABA Clubhouse has 60+ free CEUs — live every Wednesday. Ethics, supervision & clinical topics.
Join Free →Add a quick 1-to-5 “like it” card after every light-touch activity and drop the touch if the rating dips below 3.
02At a glance
03Original abstract
Interpersonal touch plays a crucial role in shaping relationships and encouraging social connections. Failure in processing tactile input or abnormal tactile sensitivity may hamper social behaviors and have severe consequences in individuals' relational lives. Autism Spectrum Disorder (ASD) is characterized by both sensory disruptions and social impairments, making affective touch an ideal meeting point for understanding these features in ASD individuals. By integrating behavioral and physiological measures, we investigated the effects of affective touch on adult individuals with ASD from both an implicit and explicit perspective. Specifically, at an implicit level, we investigated whether and how receiving an affective touch influenced participants' skin conductance tonic and phasic components. At the explicit level, we delved into the affective and unpleasant features of affective touch. Overall, we observed lower skin conductance level in ASD compared to TD subjects. Interestingly, the typically developing (TD) group showed an increased autonomic response for affective touch compared to a control touch, while ASD subjects' autonomic response did not differ between the two conditions. Furthermore, ASD participants provided higher ratings for both the affective and unpleasant components of the touch, compared to TD subjects. Our results reveal a noteworthy discrepancy in ASD population between the subjective experience, characterized by amplified hedonic but also unpleasant responses, and the physiological response, marked by a lack of autonomic activation related to affective touch. This insightful dissociation seems crucial for a deeper understanding of the distinctive challenges characterizing people with ASD and may have implications for diagnosis and therapeutic approaches.
Autism research : official journal of the International Society for Autism Research, 2024 · doi:10.1002/aur.3143