Age-Related Differences in Pro-active Driving Behavior Revealed by EEG Measures

Abstract

Healthy aging is associated with a decline in cognitive functions. This may become an issue when complex tasks have to be performed like driving a car in a demanding traffic situation. On the other hand, older people are able to compensate for age-related deficits, e.g., by deploying extra mental effort and other compensatory strategies. The present study investigated the interplay of age, task workload, and mental effort using EEG measures and a proactive driving task, in which 16 younger and 16 older participants had to keep a virtual car on track on a curvy road. Total oscillatory power and relative power in Theta and Alpha bands were analyzed, as well as event-related potentials (ERPs) to task-irrelevant regular and irregular sound stimuli. Steering variability and Theta power increased with increasing task load (i.e., with shaper bends of the road), while Alpha power decreased. This pattern of workload and mental effort was found in both age groups. However, only in the older group a relationship between steering variability and Theta power occurred: better steering performance was associated with higher Theta power, reflecting higher mental effort. Higher Theta power while driving was also associated with a stronger increase in reported subjective fatigue in the older group. In the younger group, lower steering variability came along with lower ERP responses to deviant sound stimuli, reflecting reduced processing of task-irrelevant environmental stimuli. In sum, better performance in proactive driving (i.e., more alert steering behavior) was associated with increased mental effort in the older group, and higher attentional focus on the task in the younger group, indicating age-specific strategies in the way younger and older drivers manage demanding (driving) tasks.

Keywords: EEG; aging; alpha oscillations; event-related potentials; mental effort; proactive driving; theta oscillations; workload.

Figure 1

Behavioral and EEG parameters (mean values and standard errors of means): steering variability (A), total oscillatory power (B), relative Theta power (C), relative Alpha power (D) and P3a amplitude (E) as function of Time on Task and Task Load, shown separately for young and old participants.

Figure 2

Significant relationships of behavioral and EEG parameters: Individual values of steering variability, frontal and posterior relative Theta (A), and P3a amplitude (B), averaged across Task Load and Time on Task, shown for young (y) and old (o) participants with regression lines.

Figure 3

Subjective parameters: reported pre and post driving fatigue ratings (A) and individual changes in fatigue and frontal relative Theta (B) of old (o) participants (as averaged across Task Load and Time on Task) with regression lines.