Evaluation of Body-Pressure Intervention for Self Injury in Autism

Article excerpt

There is an increasing interest in developing interventions for problem behavior in autism due in part to the recent rise in diagnosis of the disorder (e.g., Yeargin-Allsopp, Rice, Karapurkar, Doernberg, Boyle, & Murphy, 2003). Self injury is the problem behavior that is of primary concern in this population (Bodfish & Lewis, 2002). Self injury can have damaging effects both in the short and long term. In addition to the physical effects of self injury, such behavior also prevents the successful application of teaching techniques. Effective interventions for self injury associated with autism, therefore, can be beneficial along several lines. A hallmark feature of interventions designed by applied behavior analysts is the emphasis placed on an understanding of the function of the problem behavior (e.g., Carr, 1977; Iwata, Dorsey, Slifer, Bauman, and Richman (1982/1994). Self injury, in some cases, is maintained by the automatic stimulation provided by the behavior itself and, thus, is said to be stereotypical.

Because individuals with autism often are treated in a multi-disciplinary setting, including by applied behavior analysts and occupational therapists, and given the interest in sensory stimulation by occupational therapists, interventions for sensory-maintained self injury allow for collaboration across service providers. Occupational therapists interested in reducing problem behavior in autism often attribute the causes of such problem behavior to sensory disturbances. Accordingly, sensory-integration therapy is used to treat problem behavior. This therapy involves providing physiological stimulation through tactile, visual, auditory, propioceptive, and/or vestibular means. This stimulation includes, but is not limited to: swinging, auditory integration therapy, rocking, holding, brushing, "sensory diets," and deep-pressure therapies, such as the use of a weighted vest (Case-Smith & Bryan, 1999; Mason & Iwata, 1990).

Collaboration across service providers from different perspectives (e.g., applied behavior analysts and occupational therapists) may be challenged by their different training histories and their different technical vocabularies. Nevertheless, bringing different perspectives to bear on a common problem may enhance treatment, through a variation and selection process, so long as a common ground for judging the treatment is agreed upon. We believe this common ground ought to be a reliance on evidence-based practice (e.g., Horner et al., 2005; Richman, Reese, & Daniels, 1999).

There is limited research involving sensory-integration therapy in general, or involving its components specifically (Case-Smith & Bryan, 1999). Nevertheless, in one report 99% of occupational therapists surveyed considered themselves to have a "sensory-integration" orientation (Watling, Deitz, Kanny, & McLaughlin, 1999) and, therefore, might use more controversial or relatively undocumented techniques such as a weighted vest to reduce problem behavior. It is difficult to interpret many of the studies involving deep-pressure therapy, as well as other sensory-integration techniques, because of their methodological limitations, such as their use of AB designs (e.g., Case-Smith & Bryan, 1999; VandenBerg, 2001; Zisserman, 1992). In a study employing an ABA design, Fertel-Daly, Bedell, and Hinojosa (2001) found inconclusive results because in some cases problem behavior was not substantially different across phases and in other cases there was not a reversal of behavior during the return to baseline conditions.

Mason and Iwata (1990) addressed several of the methodological limitations of the studies described above and assessed the effects of sensory-integration therapy on self-injury in three individuals with intellectual disabilities. Sensory-integration therapy resulted in an increase in problem behavior for one individual and a decrease in problem behavior for the other two individuals. …