Competitive two-persons interactions of type-A and type-B individuals.

Forty subjects classified as either coronary-prone (Type A) or coronary-resistant (Type B) interacted in a mixed-motive game in pairs by pressing buttons which transmitted messages through a television screen while an electrocardiogram and digital blood volume pulse were computer monitored. Subjects could cooperate, compete, punish, reward, or withdraw during each interaction and could send 1 of 55 messages communicating feelings, requests, and intentions between interactions. Paired Type A's interacted more competitively and aggressively than paired Type B's. There were no significant differences between Type A's and Type B's in heart rate or digital vasomotor response during the interpersonal game. The behavioral results but not the physiological results confirm findings from an earlier experiment.