The new study contradicts the popular opinion that people with autism are apparently "indifferent to pain"
A new study examined the pain perception of people with autism and found that they experience pain at a higher intensity than the general population, and adapt less to the feeling of pain. This finding is contrary to the popular opinion that people with autism are apparently 'indifferent to pain', and the researchers hypothesize that the finding is related to one of the distinct characteristics of autism: a sensory dysregulation disorder. The researchers express hope that the findings of the study will lead to a more appropriate attitude on the part of medical teams, caregivers, and parents towards people with autism, who do not always express the experience of pain in acceptable ways.
The research was funded by the National Science Foundation, and was led by four researchers: Dr. Tami Bar-Shalita From the Faculty of Medicine of Tel Aviv University who initiated the research, in collaboration with Dr. Yelena Granovsky from the Technion and the Rambam Medical Center and Prof. Irit Weissman-Fogel and Prof. Einat Gal from the University of Haifa. This study formed a framework for the doctoral theses of doctoral students Tzala Hoffman and Mary Klingel-Levi, and three articles based on it have been published or accepted for publication so far. The current study was published in the prestigious journal PAIN.
Dr. Bar-Shalita explains: "About 10% of the general population suffer from sensory dysregulation disorder, which means sensory sensitivity at a level that impairs daily functioning. These people find it difficult, for example, to ignore or adapt to the buzzing and flashing of neon lights, the whirring of the air conditioner or fan, or the popcorn of the person sitting next to them in the cinema. In previous studies in the laboratory we found that these people have more pain compared to people without a sensory regulation disorder. Since it is known that sensory dysregulation is very common among people with autism - about 90-70% suffer from it, it is a criterion for diagnosing autism, and is even related to the severity of autism - we wanted to examine the perception of pain in autism. In other words, we asked: do people with autism also have more pain like all those suffering from a sensory dysregulation disorder? This issue was hardly explored before we set out."
Self-harm does not indicate indifference to pain
According to the researchers, for many years the opinion prevailed that 'people with autism have less pain' or that they are 'indifferent to pain'. In fact, 'indifference to pain' is one of the characteristics in the current definition of autism. The proof of this, apparently, was that they used to hurt themselves by self-harm. "This assumption is not necessarily correct," says Dr. Bar-Shalita, "We know that self-harm may actually stem from an attempt to suppress pain, and it is possible that they hurt themselves in order to activate, unconsciously, a physical mechanism of 'pain suppresses pain'."
This study is a laboratory pain study approved by the ethics committee of the academic institutions. The study included 52 adults with high-functioning autism, with normal intelligence - the largest sample in the world to date in studies of pain among people with autism. The study used psychophysical tests to assess pain, which are accepted in the field of pain research. These methods examine the relationship between stimulus and response, where the researcher, using a computer, controls the duration and intensity of the stimulus and the subject is asked to rate the intensity of the pain he feels on a scale of 0 to 100. The findings unequivocally proved that people with autism are more painful. Furthermore, the pain suppression mechanism is less effective in them.
The researchers explain: "We conducted a variety of measurements, the purpose of which, among other things, is to examine whether the hypersensitivity results from overexcitation of the nervous system, or rather from the suppression of mechanisms that are supposed to allow adaptation and reduce the response to stimulation over time. We found that in the case of people with autism it is a combination of the two: amplification of the pain signal alongside a less effective pain suppression mechanism."
"Our study comprehensively and in-depth examined the level of pain experienced by people with autism. The popular opinion was that they were supposedly 'indifferent to pain', and medical and other teams even treated them accordingly. The results of the study indicate that in most cases, the sensitivity to pain of people with autism is actually higher than that of the majority of the population, and at the same time they fail to effectively suppress a painful stimulus. We hope that our findings will serve the professionals and doctors treating this population, and will contribute to the promotion of personalized treatment," concludes Dr. Bar-Shalita.
In additional articles that will be published soon, the researchers examined the brain activity of people with autism during pain stimuli, and examined subgroups within this population in regards to the perception of pain.
