Zhou, L., Goff, G. A., & Iwata, B. A. (2000).
Effects of increased response effort on self- injury and object manipulation as competing responses.
Journal of Applied Behavior Analysis,
33, 29-40.
We evaluated the effects of a response-effort intervention on the
occurrence of self-injurious hand mouthing and a competing
response (object manipulation) with 4 individuals who had
profound developmental disabilities. During Phase 1, results of
functional analyses showed that all participants engaged in high
levels of hand mouthing in the absence of social contingencies,
suggesting that the behavior was maintained by automatic
reinforcement. In Phase 2, preferred leisure items were
identified for participants during assessments in which duration
of leisure item manipulation was used as the index of preference.
In Phase 3, participants were observed to engage in high levels
of hand mouthing and in varying levels of object manipulation
when they had free access to their most preferred leisure items
during baseline. The effects of increased response effort on hand
mouthing and object manipulation were then evaluated in mixed
multiple baseline and reversal designs. The response-effort
condition was identical to baseline, except that participants
wore soft, flexible sleeves that increased resistance for elbow
flexion but still enabled participants to engage in hand
mouthing. Results showed consistent decreases in SIB and
increases in object manipulation during the response-effort
condition for all participants. These results suggested that a
less preferred reinforcer (produced by object manipulation) may
substitute for a more highly preferred reinforcer (produced by
hand mouthing) when response effort for hand mouthing was
increased.
DESCRIPTORS: _self-injurious behavior, automatic reinforcement,
reinforcer substitutability, response effort