[Anticipatory and event related changes in heart rate as indicators of attention processes]

The present study was concerned with the question of whether phasic event-related heart rate (HR) changes under easy intake conditions account for the association between anticipatory HR deceleration and task performance in a choice reaction time (RT) task with a fixed foreperiod. The task employed differed from simple RT tasks especially with regard to processing and attention demands. Subjects were required to determine as quickly and accurately as possible whether a probe, presented for 80 ms, was identical or not to one of two distinct memory items, presented at the onset of each trial. Reaction times as well as accuracy of responses were determined. The results of the present study were indicative of a reliable anticipatory HR deceleration which was related to latency of responses to the probe stimulus. Subjects with stronger decelerations reacted faster than subjects with diminished or missing decelerations. Furthermore a relation was found between this association and the heart rate changes to repeated presentations of a non-signal auditory stimulus under habituation conditions. Results were discussed in terms of differences in the regulation or control of attentional processes.