Autonomic and behavioral effects of dextroamphetamine and placebo in normal and hyperactive prepubertal boys.

The hypothesis is tested that the response to dextroamphetamine in terms of activity, attention, impulsivity, and autonomic activity is similar in normal (N) and hyperactive (H) children. Fourteen N and 15 H boys had skin conductance (SC), heart rate (HR), and finger temperature (ST) recorded during rest, presentation of eight 75-dB tones, and a reaction time (RT) procedure on three occasions: off drug (Day 1) and after ingestion (double-blind) of placebo and of .5 mg/kg dextroamphetamine. Both N and H groups showed drug effects, compared to placebo, of reduced motor activity and impulsivity, improved attention (RT), increased HR and HR slowing during RT foreperiods, and decreased ST. Both groups also had decreases in SC responsivity but in different parts of the test. Placebo compared to Day 1 produced increased activity and autonomic "arousal" but no change in Rt. Stimulant drugs thus have similar behavioral and autonomic effects in both N and H boys, but the beneficial effects on behavior do not depend critically on increases in arousal.