Data from a variety of clinical populations (mentally retarded, autistic, hyperactive and normal children) and animals are reviewed. An attentional model is proposed to account for type of therapeutic response to stimulant medication. (Author)

In two experiments with profoundly retarded institutionalized individuals, 10 severely aggressive, hyperactive young adults were exposed to two daily periods of jogging and strenuous physical activities. Results indicated systematic reductions in problem behavior for eight of the 10 to levels considered "not a problem" or only "an occasional…

Thirteen children (ages 5-11) with autism and symptoms of attention-deficit hyperactivity disorder participated in a double-blind, placebo-controlled crossover study of methylphenidate. Eight subjects responded positively, decreasing their hyperactivity. Ratings of stereotypy and inappropriate speech also decreased, however, no changes were found…