Anticipatory Heart-Rate Changes: Environmental vs Self-Produced Mediation of the Time between a Warning Stimulus and the Required Response

Abstract

9 Ss participated in an experiment comparing anticipatory heart-rate changes to two different kinds of reaction times. Ss were paid for pushing a button within 500 msec, of a signal (simple reaction time) and were paid for pushing a button within ± 250 msec, of 5 sec. after a signal (internally mediated reaction time). For all Ss and under both conditions, the heart-rate was observed to decelerate during at least the 2 sec. prior to the response being made. However, return to an accelerating phase was delayed by approximately 2 sec. for the internally mediated reaction time condition.