A Comparison of Medium Probability Versus High Probability Instructions to Increase Cooperation in the Context of the High Probability Instructional Sequence

The high-probability instructional sequence has been shown to be effective to increase cooperation with low-probability requests. However, for some individuals, it may be difficult to identify high-probability instructions, and some high-probability instructions may become less likely to evoke cooperation over time. Thus, under some circumstances medium probability instructions, or instructions which may be less likely to evoke cooperation than high-probability instructions, may be a useful temporary alternative to increase cooperation. In the current study, we compared medium probability instructions to high probability instructions to increase cooperation among three children with autism spectrum disorder. The results showed that for two participants, the medium probability instructions improved cooperation as much as the high-probability instructions. For a third participant, the medium probability instructions improved cooperation over baseline, but not to the level observed with the high-probability instructions. Results are discussed in terms of the mechanisms responsible for the effects of instructional sequences.