Behavioral and Emotional Responding During Instrumental Learning in Children With ADHD: Reinforcement Schedule Effects

OBJECTIVE: Theoretical accounts of ADHD predict impaired learning under partial reinforcement and altered behavioral persistence under extinction. One of these theories (Amsel, 1992) postulates increased negative emotional responding (i.e., frustration) underlies these impairments, but to date emotional responding during instrumental learning has received limited attention. The current experimental study investigated behavioral and emotional responding during an instrumental learning task under different reinforcement schedules. METHODS: Eighty-four children with ADHD and 83 neurotypical children completed a simple instrumental learning task under a continuous (100%), partial (33%) or stretching ratio (i.e., schedule thinning; 100%-33%) reinforcement schedule, followed by a four-minute extinction phase. Negative and positive emotional expressions of the children were assessed during task completion. RESULTS: No group differences were found in either speed of acquisition or behavioral persistence under extinction with the reinforcement schedules applied in the current study. Across groups, partial reinforcement and stretching the ratios resulted in more behavioral persistence compared to continuous reinforcement, supporting the presence of a PREE effect. Children with ADHD showed more negative emotional expressions during both acquisition and extinction, irrespective of reinforcement condition. No diagnostic group or condition differences were found in the number of positive emotional expressions. CONCLUSION: Findings may have implications for instrumental learning based psychosocial treatments for children with ADHD, as their efficacy can be impacted by increased emotional responding.