NCJ Number
153729
Journal
Addictive Behaviors Volume: 18 Dated: (1993) Pages: 263-268
Date Published
1993
Length
6 pages
Annotation
This study involved 28 male undergraduates who received either 45 mg of immediate-release-oral morphine tablets or a placebo; they were then given the opportunity to administer electric shocks to an increasingly aggressive bogus opponent during a competitive reaction time task.
Abstract
Subjects were randomly assigned to either a morphone condition or a placebo condition. They were informed that they would be competing with other subjects in the adjoining room. Shock "unpleasantness" thresholds for both subject and opponent were determined by administering a series of increasing shock intensities. Each subject competed with the opponent for a series of 21 trials and completed a post-task questionnaire following the reaction time task. Aggression was defined as the magnitude of shock that the subject selected for his opponent to receive. Results showed that subjects in the morphine condition were more willing to initiate attacks against their opponent than subjects in the placebo condition. Further, subjects in the morphine condition reacted more aggressively than subjects in the placebo condition at all levels of provocation. Study findings suggest that the traditional view of opiates reducing aggressive behavior requires re-examination. A possible explanation for enhanced aggression in the morphine condition is offered that involves the analgesic properties of morphine. Another potential hypothesis, that morphine-induced aggression is mediated by arousal changes, is not supported. 20 references and 1 table