Microswitches are critical tools that can help people with multiple disabilities control aspects of their environment, including their favorite environmental stimuli through simple responses (Crawford & Schuster, 1993; Gutowski, 1996). One such response may be vocalization (that is, any brief sound emission) (Lancioni, O?Reilly, Oliva, & Coppa, 2001). Such a response can be present in children who have little motor behavior and seems to be highly valued by staff and parents, probably because it is closely linked to verbalization or speech (McCathren, Yoder, & Warren, 1999).