Effects of d-amphetamine on aggressive responding of normal male subjects.

Male research subjects were administered placebo and three doses of d-amphetamine (5, 10, and 20 mg/70 kg of body weight) under double-blind conditions in a laboratory situation that provided both aggressive and nonaggressive response options. The nonaggressive response was button pressing maintained by the presentation of points which were exchanged for money. The aggressive response was button pressing on a separate manipulandum which ostensibly subtracted points from a fictitious person. Aggressive responding was initially established by subtracting points from the research subjects, which was attributed to the other person. d-Amphetamine increased nonaggressive responding, while aggressive responding was generally decreased.