Group loyalty, communication, and trust in a mixed-motive game

The present research studied the influence of reward conditions, group membership, and personality variables on communication, attitude ratings, and per cent of cooperative choices in the mixed-motive Prisoner's Dilemma game. Volunteers from two open neuropsychiatric wards of the Houston V. A. Hospital, the Patient Training Laboratory and a group psychotherapy ward were assigned randomly to one of two experimental treatments: (1) An individual reward (IR) condition; or (2) A group reward condition (GR). Under the IR condition, Ss were instructed that the individual who won the most points would be awarded two dollars in addition to the money he won in the game. Under the GR condition, Ss were instructed that each individual from the winning ward would receive two dollars in addition to what he won in the game. The IR and GR Ss were further randomly subdivided into six intergroup dyads and six intragroup dyads. The California Personality Inventory, FIRO-B, and the Army General Classification Test were administered several days prior to the experiment proper. These personality and intelligence scores were correlated with seventeen behavioral and attitude measures taken during the actual play of the game. Analysis of the results revealed five major findings: (1) There was lack of any impressive relationships between intelligence, personality, and game behavior; (2) The social-psychological relationships of the players proved to be a significant determinant of game behavior; (3) The Initial attitude scores were significantly more positive or favorable when Ss played a member of their own ward as compared to when Ss played against members from another ward and this difference became even greater as the game developed; (4) The reward conditions used in this experiment were not sufficiently powerful to singularly alter game behavior but the reward factors intensified the inclination of members to trusting and distrusting behaviors based on group membership characteristics; and (5) Evidence emerged supporting the potency or importance of the early trials for determining the course of the game.