Aging and the psychological refractory period: Task-coordination strategies in young and old adults

The apparently deleterious effect of aging on dual-task performance is well established, but there is Little agreement about the source of this effect . Studies of the psychological refractory period (PRP) indicate that young adults can flexibly control dual-task performance through task-coordination strategies. Thus, the performance of older adults might differ from young adults because older adults use different task-coordination strategies. To test this hypothesis, the executive-process interactive control (EPIC) arch itecture was applied to quantify the reaction time data from two PRP experi ments conducted with young (age 18-26) and older (age 60-70) adults. The re sults show that participants' ability to coordinate the processing of two t asks did not decline with age. However, dual-task time costs were greater i n the older adults. Three sources for this increase were found: generalized slowing, process-specific slowing, and the use of more cautious task-coord ination strategies by the older adults.