Effects of Incentive and Preparatory Interval on Activity, Heart Rate, and Reaction Time in Children

Abstract

To resolve certain empirical and theoretical difficulties concerning, primarily, the significance of phasic heart-rate deceleration prior to reaction signals, 48 children were employed to perform in simple reaction-time tasks while speed, heart rate, head movement, gross movement, and blink activity were recorded. The independent variables were length and mode of presentation of preparatory intervals and level of incentives. Reaction time varied with incentive, with preparatory interval and mode of presentation. Phasic heart-rate deceleration varied with the intervals but not incentive or mode of presentation. There was little relation between deceleration and RT. Heart rate and somatic movement measures (especially of blinking) were roughly concordant at a group level but did not correlate.