Physiological responses of type A and type B men during cognitive performance.

Twenty male medical students classified as Type A or Type B solved a Concept Identification (CI) problem while measurements were taken on cardiovascular and somatic activity. The As produced significantly more overall electromyogram (EMG) activity and greater vasomotor activity than the Bs at baseline and during the task. Both Type As and Bs showed significantly higher levels of Heart Rate (HR), systolic and diastolic blood pressures, skin conductance, frontal EMG, and lower levels of vasomotor activity during work on the problem than during pre- and post-problem baselines. Type As showed significant negative correlations between total errors during CI and level of vasomotor activity, and between postsolution response latency and skin conductance. Type Bs showed a strong positive association between presolution response time and heart rate that did not hold for the As. The As appear to have shown sympathetic activation associated with quality of problem-solving performance, while the B's showed a relationship that suggested an impaired efficiency of performance associated with cardiac activation.