Environmental enrichment and response cost: immediate and subsequent effects on stereotypy.

Watkins et al. (2014) tested whether adding response cost to environmental enrichment would cut stereotypy faster than enrichment alone. They ran a single-case design with several participants whose diagnoses were not specified. Sessions alternated between enrichment-only and enrichment-plus-cost conditions.

Stereotypy dropped right away when response cost was added. Most participants kept low levels even after the cost was removed. Enrichment by itself did not give the same quick suppression.

Reid et al. (2003) seems to tell the opposite story. They gave kids highly preferred items on a steady schedule and saw stereotypy grow stronger. The difference is function: their behavior was automatically reinforced; no social payoff was involved. Adding cost in the 2014 study likely blocked that automatic payoff, turning the tide.

Hagopian et al. (2000) also used noncontingent reinforcement alone and wiped out problem behavior. Their target behaviors served social functions, so free toys acted as substitutes. Stereotypy that feeds on its own sensation needs the extra punch of cost, exactly what Nicholas showed.

WEINER (1964) first mapped the nuts and bolts of response cost in a token lab. Nicholas moved the same lever into a clinical setting and hit stereotypy instead of lever presses.

If you run enrichment sessions and stereotypy barely budges, do not toss the toys yet. Pair preferred items with a small, immediate cost—loss of a point, token, or minute of screen time. The combo gives the child something better to do and a reason to stop the repetitive movement. Start with one behavior, one cost, and watch the data; you can thin the cost later once low rates hold steady.