“…However, this approach is impractical for teaching children with autism because failure to present instructional demands virtually eliminates learning opportunities. As a result, several studies have shown that it is possible to alter the demands and then re-introduce them along a variety of dimensions including task difficulty (Cameron, Ainsleigh, & Bird, 1992;Weeks & Gaylord-Ross, 1981), number of low probability requests (Ducharme & Worling, 1994), response effort Richman, Wacker, & Winborn, 2001;Wacker et al, 1990;Weld & Evans, 1990) and number or rate of instructional trials (Kennedy, 1994;Pace, Iwata, Cowdery, Andree, & McIntyre, 1993;Zarcone, Iwata, Smith, Mazaleski, & Lerman, 1994;Zarcone, Iwata, Vollmer, Jagtiani, Smith, & Mazaleski, 1993). For example, Pace et al (1993) used a combination of extinction and fading instructional demands to reduce escape-motivated problem behaviors.…”