CARDIAC AND BLINK REFLEX CONCOMITANTS OF ATTENTIONAL SELECTIVITY - A COMPARISON OF ADULTS AND YOUNG-CHILDREN

Selective attention, often considered less efficient in young children, was examined in adults and 5-yr-olds using a new, startle-probe technique. To investigte the allocation of preparatory attention at early stages of processing, we examined the modification of the startle blink reflex to irrelevant acoustic probes presented within the warning interval (WI) of a simple reaction time task. Attention was directed away from the acoustic probes and toward a vibrotactile GO signal during the 6-s WI. Heart rate decelerated prior to the GO signal in both children and adults, implying increased attention. The two groups showed opposite patterns of blink modification, however. In adults, startle blink to the WI probes was increasingly attenuated as the GO signal approached, suggesting a selective pattern of attentional allocation. In contrast, blink amplitude increased linearly across probe positions in children, implying that preparatory attention was allocated to a wider range of sensory input.