The proposed research will evaluate the effectiveness of the opiate antagonist naltrexone and positive behavioral intervention programs in treating self-injurious behavior in 24 adults with developmental disabilities in community residential settings. Several converging lines of evidence suggest that self-injurious behavior is a multiply determined phenomenon with several distinct etiologies and/or current regulatory mechanisms. While many forms of self-injury appear to be maintained by environmental consequences (e.g., attention from others, escape from unpleasant or demanding tasks, access to preferred objects or activities), others appear to have a neurochemical basis. Recent research reveals that some forms of self-injury are responsive to treatment with opiate antagonist drugs, suggesting the involvement of the endorphin/enkephalin ligand system in the maintenance of self-injurious behavior. In addition to attenuating pain, endorphins serve as powerful reinforcing stimuli. It is proposed that after repeated self-injury, with associated endorphin release, an individual becomes physically dependent upon the endogenous opioid chemicals. Because discontinuation of self-injury would induce an opiate-type abstinence syndrome, the individual may continue to engage in self-injury to avoid withdrawal distress. Our preliminary work on this topic, together with the results of several published reports, implicate opioid mechanisms in self-injury in people with developmental disabilities. In a majority of cases, treatment with opiate antagonist drugs reduce or eliminate self-injury. However, some patterns of self-injury are not responsive to opiate antagonists, suggesting the involvement of other factors. Recent evidence indicates that patterns of self-injury can be distinguished on the basis of the environmental circumstances under which it occurs, which may provide a basis for isolating distinct subgroups of self-injurious individuals. The goal of the proposed research is to integrate these environment-based approaches with those based on opioid mechanisms in the treatment of self-injurious behavior. A two-phase experimental/treatment strategy is proposed, wherein two groups of 12 subjects each will receive either naltrexone or behavioral interventions during one phase and a combination of both treatments during a second phase. The naltrexone trial will consist of a double-blind crossover design with placebo and 100 mg/day naltrexone. The behavioral interventions will focus on replacing self-injurious behavior with functional, adaptive skills. Frequency and intensity of self-injury constitute primary dependent variables, as measured by direct observational methods and by staff ratings. In addition, the present research will include a detailed microanalysis of the ongoing environmental circumstances accompanying both self-injury and other response classes that covary with self-injury. This will not permit greater specification of the environmental mechanisms through which self-injury occurs under normal (pre-intervention) conditions, it will also reveal how the ongoing stream of behavior, including adaptive functioning, is modified by naltrexone, by behavioral interventions, and by their combination.

Agency
National Institute of Health (NIH)
Institute
Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD)
Type
Research Project (R01)
Project #
5R01HD022415-05
Application #
3321936
Study Section
Human Development and Aging Subcommittee 3 (HUD)
Project Start
1987-01-01
Project End
1995-03-31
Budget Start
1992-04-01
Budget End
1993-03-31
Support Year
5
Fiscal Year
1992
Total Cost
Indirect Cost
Name
Vanderbilt University Medical Center
Department
Type
Schools of Education
DUNS #
004413456
City
Nashville
State
TN
Country
United States
Zip Code
37212
Symons, F J; Davis, M L; Thompson, T (2000) Self-injurious behavior and sleep disturbance in adults with developmental disabilities. Res Dev Disabil 21:115-23
Symons, F J; Thompson, T (1997) Self-injurious behaviour and body site preference. J Intellect Disabil Res 41 ( Pt 6):456-68
Thompson, T; Hackenberg, T; Cerutti, D et al. (1994) Opioid antagonist effects on self-injury in adults with mental retardation: response form and location as determinants of medication effects. Am J Ment Retard 99:85-102