Date of Award


Degree Name

Master of Arts



First Advisor

Dr. James E. Carr

Second Advisor

Dr. Linda A. LeBlanc

Third Advisor

Dr. Jack Michael

Access Setting

Masters Thesis-Open Access


Tangible superimposition and withdrawal is a reductive procedure in which a new stimulus is delivered following behavior already maintained by a different controlling stimulus. The new stimulus is then removed in an attempt to reduce behavior. The current investigation sought to extend previous research on this procedure by evaluating its efficacy and durability as a treatment for stereotypy in three children diagnosed with autism. First, automatic reinforcement functions for stereotypic behaviors were identified via functional analyses. Next, for two participants, tangible items were delivered contingent upon stereotypy and then subsequently withdrawn. When the superimposition procedure proved ineffective, environmental enrichment was implemented and was found to be efficacious in reducing the stereotypy of both participants.