Twelve experienced truck drivers drove a fixed-base driving simulator for three 8-hour sessions under simulated nighttime driving conditions. Sessions included no glare, intermittent glare presented in the exterior rearview mirrors to simulate following vehicles, and intermittent glare with electrochromic glare reduction. The driving task combined vehicle control on straight and curved road segments with detection of pedestrians appearing alongside the road and targets appearing in the rearview mirrors. The presence of glare slowed detection of pedestrians and, to a lesser extent, slowed the detection of targets appearing in mirrors. Glare was also associated with increased lane position variability, reduced speed on curves, and, most consistently, increased steering variability. Alerting participants to the imminent presence of targets eliminated most of the impairment attributable to glare for detection of targets in the rearview mirrors. This provides support for the conclusion that the locus of glare impairment in a target detection task is primarily attentional rather than visual. The study found only meager evidence that electrochromic glare reduction improved target detection performance and no evidence that glare reduction improved vehicle control, despite the fact that participants consistently voiced positive preferences for glare reduction.
Abstract