Movement time differentiates extraverts from introverts

67 female subjects who were classified on the Eysenck Personality Questionnaire-Revised were compared on simple reaction time and stimulus-response compatibility tasks. Response time on these tasks was defined in terms of reaction time (RT) and movement time (MT). On the simple reaction time task, the distance of the target button from the home button was varied. The stimulus-response compatibility task examined the interaction of extraversion with stimulus evaluation demands and response requirements. For both tasks, and across all conditions, the MTs of extraverts were faster than those of the introverts, but no relation with RT was observed. These results support the view that individual differences in extraversion are influenced by differences in fundamental motor mechanisms. (C) 1997 Elsevier Science Ltd.