Aging and Individual Differencies

Objective: The nature of increased-age-related dual-task interference was examined during a driving-like dual task in the laboratory. Background: Previous research revealed age-related deficits in dual tasks especially when cognitive and motor demands are involved. The specific contributions of sensory input, working memory demands, and/or coordination of motor responses to dual-task interference are not clear and should be clarified in the present study. Method: Younger and older participants performed a driving-like tracking task and a visually cued attention task within a dual task. Behavioral and electrophysiological data were recorded during task performance. Results: Overall tracking performance was lower for the older versus younger participants. This agerelated decline was particularly pronounced in the time interval after the stimulus when the attention task demanded a motor response. In contrast, older participants tracked relatively better than the younger participants in the time interval preceding the stimulus. In the attention task, the older versus younger participants showed increased responses times and rates of false alarms and misses, suggesting a deficit in retaining the context in the cue-stimulus interval. The electroencephalogram data suggest that the older participants invested more resources than the younger participants in dual-task management during the cue-stimulus interval. Conclusion: Evidence was found for increased motor interference and a deficient context processing as well as for an increased investment of processing resources in the older compared with the younger group. Application: The results suggest that in-vehicle information systems for older drivers should be designed to support cue maintenance and that simultaneous motor demands should not be required.