On the relation between object manipulation and stereotypic self-injuriousbehavior

Results from a number of studies have shown an inverse relationship between stereotypic behavior and object manipulation. The purposes of this study w ere to determine whether techniques similar to those used previously (promp ting and reinforcement) would be effective in increasing object manipulatio n under both prompted and unprompted conditions, and to ascertain whether i ncreases in object manipulation would result in decreases in stereotypic se lf-injurious behavior (SIB). Two individuals with developmental disabilitie s who engaged in SIE maintained by automatic reinforcement participated. Re sults showed that object manipulation increased From baseline levels when e xperimenters prompted participants to manipulate leisure items, but that ob ject manipulation was not maintained under unprompted conditions, and rates of SIE stayed within baseline level. We then attempted to increase object manipulation Further by (a) reinforcing object manipulation, (b) blocking S IE while reinforcing manipulation, and (c) preventing SIE by applying prote ctive equipment while reinforcing object manipulation. Reinforcing object m anipulation alone did not affect levels of object manipulation. Blocking ef fectively reduced attempts to engage in SIE for 1 participant but produced no increase in object manipulation. When the 2nd participant was prevented from engaging in SIE through the use of protective equipment, rates of obje ct manipulation increased dramatically but were not maintained when the equ ipment was removed. These results suggest that stimulation derived from obj ect manipulation, even when supplemented with arbitrary reinforcement, may not compete with stimulation produced by stereotypic SIE; therefore, direct interventions to reduce SIE are required.