Determinants of adult age differences on synthetic work performance.

Synthetic work research is designed to simulate complex work activities by requiring participants to perform several concurrent asks. The current project consisted of 2 studies in which adults of different ages performed 4 tasks during 25 sessions in a synthetic work situation in 5-min periods across 3 days. Large age differences were evident in the total score in both studies, and they were maintained across all stages of practice. Detailed analyses revealed that with increased age adults in this time management activity were less likely to perform self-paced tasks and to attempt difficult auditory discrimination judgments. Very little independent age-related influences were evident after the initial few sessions on the task. More than 70 % of the age-related variance after nearly 2 hr of practice was shared with measures of processing speed obtained before performing the tasks. These results suggest that age-related ifferences in basic processing efficiency may be responsible for a large proportion of the age-related influences on the performance ofmoderately complex activities presumed to be similar to