Effects of prior access and environmental enrichment on stereotypy

A young boy's stereotypy was first evaluated in two daily 30 min sessions (one in the morning and one in the afternoon) during a free operant (FO) condition. Results from the two daily sessions during FO showed that stereotypy was lower during the second session of the day, suggesting that prior access had affected later engagement in stereotypy. The effects of environmental enrichment (EE) with music, EE music plus a guitar, and EE music plus a guitar plus contingent music loss on stereotypy were also evaluated. Unexpectedly, the results showed that the presence of music increased stereotypy during both daily sessions; however, contingent music loss decreased stereotypy and simultaneously increased untargeted guitar play. Increases in stereotypy during both daily sessions suggest that music may have increased the reinforcing value of stereotypy. Copyright © 2004 John Wiley & Sons, Ltd.