DIFFERENTIAL-EFFECTS OF METHYLPHENIDATE AND SELF-REINFORCEMENT ON ATTENTION-DEFICIT HYPERACTIVITY DISORDER

Six boys aged 9 to 12 years attended a tutoring class focusing on read ing for 30 minutes each morning, The investigators employed a modified Latin-square design in which each child began with a 5-day baseline p hase followed by six 10-day treatment phases that used drug placebo, n oncontingent reinforcers, 0.3 mg/kg methylphenidate, 0.7 mg/kg methylp henidate, and self-reinforcement in various combinations. Amount of ac ademic performance was the major measure of outcome and the target beh avior of self-reinforcement. Drug placebo and noncontingent reinforcer s had no systematic impact, Methylphenidate had differential effects a cross the recorded behaviors. Self-reinforcement improved the target b ehavior; the mean effect size for self-reinforcement was 2.66. The com bined effects of methylphenidate and self-reinforcement on academic pe rformance were greater than either of the treatments given alone (mean effect size = 2.89).