HYPERKINESIS, AUTONOMIC NERVOUS SYSTEM ACTIVITY AND STIMULANT DRUG EFFECTS

Abstract

SummaryThis study focused on the degree to which resting levels of autonomic “arousal” were related to hyperkinetic behaviors and stimulant drug responses. A total of 24 boys served as subjects, 12 of whom were hyperkinetic and had a history of responding well to methylphenidate while 12 normal boys served as a matched control group. The control boys were evaluated once while the hyperkinetic boys were seen on three occasions during which they participated in a double‐blind, placebo‐controlled crossover study of methylphenidate. All children were evaluated using five psycho‐physiological measures of autonomic nervous system activity and 11 objective measures of activity level and attention taken across four experimental settings. Results indicated no significant differences between hyperkinetic and normal boys in psychophysiological activity. In addition, no consistent relationships between this activity and the objective behavioral measures in either normal or hyperkinetic boys were observed. Improvements in activity level and attention during drug treatment were generally not related to the pretreatment levels of arousal in the hyperkinetic boys. Methylphenidate did not produce any significant effects on autonomic activity. Thus, results suggested that no simple level of arousal hypothesis can account for the behavior patterns of hyperkinetic children and that level of arousal is not a particularly useful predictor of drug responding in these children.