NINETY-SIX MALE UNIVERSITY STUDENTS PARTICIPATING IN THE EXPERIMENT AS PAID VOLUNTEERS WERE FIRST ASKED TO WRITE A BRIEF DESCRIPTION OF THEMSELVES. THEY WERE SUBSEQUENTLY TOLD THAT THROUGH AN EXCHANGE OF PAPERS EACH SUBJECT WOULD EVALUATE THE PAPER OF ANOTHER PARTICIPANT. IN FACT, THE EXPERIMENTER COMPOSED PRECISE NUMBERS OF INSULTING AND NONINSULTING EVALUATIONS WHICH WERE SHOWN THE SUBJECTS, THUS INTENDING TO STIMULATE AGGRESSION IN SOME AND NOT OTHERS. THROUGH A CONTRIVED INTERRUPTION OF THIS PHASE OF THE EXPERIMENT, A VIOLENT SEGMENT (A 6-MINUTE PRIZE FIGHT) FROM THE FILM 'CHAMPION' WAS SHOWN, AT THE CONCLUSION OF WHICH SOME WHO WERE PREVIOUSLY INSULTED BY SUPPOSED EVALUATIONS BY FELLOW PARTICIPANTS WERE GIVEN THE IMMEDIATE OPPORTUNITY TO WRITE AN EVALUATION OF THE ONE WHO HAD PREVIOUSLY EVALUATED THEM. OTHERS WHO HAD BEEN INSULTED WERE NOT ASKED TO WRITE THIS EVALUATION UNTIL AN HOUR AFTER THE CONCLUSION OF THE FILM. OTHERS IN THE GROUP, SOME HAVING RECEIVED INSULTING EVALUATIONS AND OTHERS NEUTRAL ONES, WERE SHOWN A NONVIOLENT FILM. UPON SCORING THE SUBJECTS' WRITTEN STATEMENTS ABOUT THEIR EVALUATORS, IT WAS FOUND THAT: (1) FOR THOSE GIVEN THE IMMEDIATE OPPORTUNITY TO BE AGGRESSIVE, THE VIOLENT MOVIE INCREASED THE STRENGTH OF THE ANGERED SUBJECTS' INITIAL ATTACK ON THEIR EVALUATORS COMPARED WITH THAT DISPLAYED BY THE SIMILARLY INSULTED MEN SHOWN THE NONAGGRESSIVE FILM; (2) THE ANGRY SUBJECTS HAVING TO WAIT AN HOUR BEFORE EVALUATING THEIR CRITICS SHOWED NO DIFFERENCE BETWEEN THE AGGRESSIVE AND NONAGGRESSIVE MOVIE GROUPS; (3) THE AGGRESSION-HEIGHTENING EFFECT OF THE VIOLENT FILM DID CARRY OVER THE INTERVENING HOUR IF THE INSULTED MEN HAD BEEN GIVEN THE EARLIER OPPORTUNITY TO EVALUATE THEIR CRITICS. IT IS SUGGESTED THAT THE PERFORMANCE OF AN AGGRESSIVE RESPONSE SOON AFTER SEEING AN AGGRESSIVE FILM INCREASES THE PERSISTENCE OF THE AGGRESSIVE REACTIONS OVER TIME. (RCB)