Neuropsychological Correlates of Changes in Driving Behavior Among Clinically Healthy Older Adults

Abstract

Objectives: To determine the extent to which cognitive domain scores moderate change in driving behavior in cognitively healthy older adults using naturalistic (Global Positioning System-based) driving outcomes and to compare against self-reported outcomes using an established driving questionnaire.

Methods: We analyzed longitudinal naturalistic driving behavior from a sample (N = 161, 45% female, mean age = 74.7 years, mean education = 16.5 years) of cognitively healthy, nondemented older adults. Composite driving variables were formed that indexed "driving space" and "driving performance." All participants completed a baseline comprehensive cognitive assessment that measured multiple domains as well as an annual self-reported driving outcomes questionnaire.

Results: Across an average of 24 months of naturalistic driving, our results showed that attentional control, broadly defined as the ability to focus on relevant aspects of the environment and ignore distracting or competing information as measured behaviorally with tasks such as the Stroop color naming test, moderated change in driving space scores over time. Specifically, individuals with lower attentional control scores drove fewer trips per month, drove less at night, visited fewer unique locations, and drove in smaller spaces than those with higher attentional control scores. No cognitive domain predicted driving performance such as hard braking or sudden acceleration.

Discussion: Attentional control is a key moderator of change over time in driving space but not driving performance in older adults. We speculate on mechanisms that may relate attentional control ability to modifications of driving behaviors.

Keywords: Attentional control; Naturalistic driving; Self-regulation.

Figure 1.

Moderating effect of attentional control on the driving space composite (p < 0.001). Trend lines are estimated at the mean attention score and 1 SD above and below the mean. A decrease in the driving space composite indicates a reduction in driving activities (e.g., driving fewer trips per month).

Figure 2.

Moderating effect of attentional control on specific components of the driving space composite. Trend lines are plotted at 1 SD below the mean (solid line), the mean attention score (short dashed line) and 1 SD above the mean (long dashed line). All outcomes are plotted in the original metric except the radius of gyration and distance traveled which were both log-transformed.

Figure 3.

Moderating effect of episodic memory on self-reported weekly miles driven on the Driving Habits Questionnaire. Trend lines are plotted at 1 SD below the memory mean, at the mean memory score, and 1 SD above the mean.