Abatement of intractable vocal stereotypy using an overcorrection procedure

We conducted a series of reversals to compare the effects of four different treatments on vocal stereotypy emitted by a 7‐year‐old boy with autism. The results showed that (1) the level of vocal stereotypy decreased during exposure to matched stimulation but returned to high levels immediately upon its removal; (2) stereotypy did not significantly decrease during differential reinforcement of other behavior; and (3) contingent withdrawal of movies and music (i.e., response cost) was only moderately effective. However, positive practice overcorrection decreased vocal stereotypy by clinically significant levels. Further, when differential reinforcement of engagement in a Lego ® building task was implemented, the level of engagement was significantly higher when positive practice overcorrection was in place than when overcorrection was withdrawn.