Association for Behavior Analysis International

Individuals with Down syndrome show a distinct behavioral phenotype characterized by relative weakness in expressive language and relative strengths in social interest. The characteristic phenotype of individuals with Down syndrome develops early in infancy with delays in the duration and frequency of exploratory motor behavior (manipulating a toy in the hand) and in the onset of babbling, speech sounds and vocal imitation. We present a behavior-analytic model, which explains the early differences in exploratory motor and speech sounds. Using this model, we examined interventions for infants with Down syndrome. A behavior-analytic intervention involving multiple opportunities, prompting, and social reinforcement was used to teach three infants with Down syndrome between 5-9 months of age to emit exploratory motor behavior with the same frequency and duration as typically developing infants. We also examined contingent vocal imitation as a reinforcer to increase the rate of babbling in infants with Down syndrome. The importance of these findings and collateral changes in related skill areas will be discussed.

Maximizing outcomes for learners with Down syndrome requires an approach which is both effective and efficient. Modifying the intensity of intervention has the potential to affect the rate of skill acquisition as well as other learner behavior, such as task persistence, which alters the efficiency of intervention. We will discuss the results of study which determined the effect of varying intensity levels of discrete-trial instruction on acquisition and task persistence for young children with Down syndrome. Three children with Down syndrome were taught expressive language targets using three manipulations of intervention intensity (dose): the number of opportunities, the spacing of opportunities, and the session duration. We measured the effects of intensity on skill acquisition and task persistence (off-task behavior and affect). Children acquired targets faster in conditions in which the spacing of opportunities was shorter than conditions in which the spacing was longer. Manipulating dose produced individual differences during the different intensity levels in the two measures of task persistence.

Parents and professionals typically report problem behavior (e.g., aggression, self-injury, tantrums) as their greatest concern regarding their children with fragile X syndrome (FXS). However, there is currently a paucity of applied intervention research to reduce problem behavior and improve quality of life in this population. We will discuss the results of our study which explored whether behaviorally-based assessment and intervention targeting specific problematic contexts would result in a reduction in problem behavior and an improvement in quality of life for three children with FXS and their families. Based on the results of a functional assessment, a multi-component intervention plan was developed to teach the parents and child to effectively cope with the problematic context. A multiple baseline design was used to demonstrate intervention effects for specific high-priority contexts (bedtime, running errands, and toileting) in home and community settings. Following intervention, there were substantial improvements in problem behavior and family quality of life for all three participants within the targeted contexts. Results demonstrated that many of the behaviors observed in children with FXS are amenable to behavioral interventions that involve altering the antecedents and consequences related to such behaviors. We will also present data comparing direct versus indirect prompting in FXS.