Age-Related Differences in Using Optical Flow and Landmark Information for Steering Control

The present study examined age related decrements in the use of optical flow and landmark information for the control of steering. Older and younger drivers were presented with computer generated displays simulating vehicle motion through a random dot ground plane scene and they were asked to steer the vehicle to null out the side wind perturbation. In the first experiment, on half the trials landmark information was presented by color coding one of the dots on the ground plane. In the second experiment the number of landmark in the scene was manipulated. Overall younger drivers had reduced steering error than older drivers. Older drivers, as compared to younger drivers, also had reduced steering error when more landmark information was present with rich optical flow information. These results suggest that older drivers may be more reliant on optical flow information for controlling a vehicle and may have a reduced ability to use alternative sources of information, such as landmarks, for steering control.