Age Tracking Performance and the Measurement of Workload by a Secondary Tasks

The purpose of this study was to investigate age differences in tracking performance and in the amount of workload imposed by the tracking task. Twelve subjects between the ages of 18 and 22, and 12 subjects between the ages of 48 and 67 performed a serial, choice-reaction-time task alone and concurrently with a pursuit rotor tracking task. The choice reaction time task served as the secondary task and the pursuit rotor tracking task as the primary task. Primary task performance was measured by time on target and number of tracking errors, and the secondary task by choice reaction time and percent correct responses. Additionally, workload, as defined by Ogden et al. {1979) and Michon (1966) was evaluated as a function of age and tracking complexity. Results related to tracking performance revealed significant age and tracking complexity main effects, Results also showed that tracking complexity affected choice reaction time and that age affected percent correct responses. Significant tracking complexity and age main effects were revealed for the workload measure in choice reaction time. This suggests that the complexity of the tracking task affected the amount of workload, and that the tracking task imposed a greater workload on the older subjects. The implications of age differences in the amount of workload imposed on the subjects were discussed.