Self-injury: How and if pain is perceived could be a key

Matt, a 10-year-old boy living at home and attending a special education classroom for students with cognitive impairments in a public school, spends much of his waking hours biting his hands, arms, and legs, scratching and pinching his face, and banging his head against hard surfaces like desks and doors. Sometimes he draws blood, and permanent scarring is evident on his hands and wrists. Matt has been injuring himself like this since he was about three years old.

Nothing has consistently reduced Matt’s self-injurious behavior and his parents and teachers are desperate for help to prevent him from continuing to harm himself. Children like Matt are among the most disturbing and difficult educational, clinical, and scientific puzzles. Self-injurious behavior (SIB) is one of the most devastating behavior problems faced by children and adults with developmental disabilities and their families.

Frank Symons, associate professor of special education, is working to understand possible biological underpinnings for the severe self-injurious behavior of children like Matt, primarily those with developmental disabilities and emotional or behavioral disorders.

Symons is a primary researcher in a five-year federal study that will be integrating two worlds of research—behavioral research into self-injury and biologically-based pain research.

“One question you have when you see someone injuring themselves is, ‘Why do they do it? Doesn’t it hurt?’” Symons says. “But with a person who is noncommunicative or unable to reliably communicate, this is a difficult question to answer. Right now we really don’t have answers to questions such as, ‘Do some people with severe self-injurious behavior have altered levels of brain chemicals that influence their ability or inability to feel pain?’ We don’t know if altered pain perception influences whether a treatment will be effective.”

From a behavioral learning theory perspective, some forms of self-inflicted injury among persons with developmental disabilities are, in part, learned phenomena related to a lack of ability to effectively communicate.

Symons explains. “When a person who cannot communicate does something to hurt himself, it usually produces immediate social consequences. For many individuals, the behavior becomes learned as a way of communication, however imperfect. This model predicts, and much research confirms, that teaching the person to communicate more effectively will reduce self-injury.”

Alternative theories, however, are based on biological mechanisms. Evidence indicates that self-injury represents altered neurochemistry involving neurotransmitters like dopamine and serotonin, and the endogenous opioid peptides, our bodies’ natural “pain killers.”

Symons is interested in discovering the possible role of underlying neural sensory pathways that might prevent a person from feeling pain or interpreting it correctly and whether this might be related to self-injury.

“I see an artificial dichotomy between the behavioral and biological concepts,” Symons says. “It is most likely that there is an interaction between the social and biological that can lead to self-injurious behavior. Because you can show that social consequences can affect a behavior problem does not mean biology is irrelevant and vice versa.”

To try to untangle the questions involved, Symons will look at the longstanding problem of self-injury through the relatively new lens of pain mechanisms. For the study, he is recruiting children and adults with severe and profound developmental disabilities who engage in tissue-damaging self-injury.

“One marker for pain is facial action,” Symons says. “We can code changes of facial expression as an objective measure of pain to determine if pain is being expressed during an act of self-injury compared to facial expression during routine vaccinations, for example.”

Symons hopes the research will lead to more effective and targeted treatment for those individuals whose self-injury does not appear related to communicative barriers or learned behavior.

“Right now for individuals with chronic tissue-damaging self-injury for which communication does not seem to be a factor, the standard treatments include physical restraints or some level of sedation,” Symons says. “But if we find that the behavior has a biological basis in the brain and neural system, we might be able to devise treatments that won’t require those restrictive measures. It might also have broader implications for management of chronic pain in the general population.”

—Peggy Rader