An Overview of Pain in Autism: Investigating Differences in Sensation, Feeling and Behaviours

Background:   In contrast to the well-known and extensively studied social communication challenges that characterize ASD, sensory atypicalities, which are also included in the core diagnostic criteria, are not well understood. In DSM-V criteria insensitivity to pain is cited as an example of these sensory atypicalities, however there is limited research evidence or consideration of what aspects of pain perception are measurable in this population.

Objectives:  In a systematic review, a comprehensive search was utilized to identify research articles addressing the topic of pain in ASD.

Methods:   Studies were identified using a range of relevant search terms including ‘(pain OR noxious OR nociception OR nociceptive OR C-fibers) & (Autism OR Asperger syndrome OR ASD OR Autistic)’, in addition, hand searches from relevant journals, screening the reference sections of articles considered, and consultation from other experts in the field. Articles were eligible for inclusion if they included a well-defined sample of individuals with ASD, were written in English, and included a quantifiable measure of pain response or perception. Included articles used a variety of methods to assess pain sensitivity, including self-report, observations of behavioural changes in response to pain, and response to experimental pain models. 

Results:   The findings of the review show that both self/parent report and clinical observations appeared to report hyposensitivity to pain, whereas observations of medical procedures and experimental manipulation suggested normal or hypersensitive responses to pain. 

Conclusions:  The current state of the research leaves a large number of questions unanswered and fails to consider the reasons for or implications of altered pain perception in ASD. This introductory talk and the symposium at large will begin to address these core concerns. Further, in consideration of these limitations, we will also report preliminary data from our lab, which systematically considers response to a range of experimental pain models and motivational aspects of pain in individuals with ASD.