Observers' Judgments of the Effects of Glare on Their Visual Acuity for High and Low Contrast Stimuli.

Disability glare refers to a reduction in the ability to discern a stimulus that is positioned near another stimulus that has a much higher luminance. While it is common for drivers to report that they have been "blinded" by oncoming headlights, it is unclear whether observers can accurately judge when they are visually disabled by glare. This experiment sought to quantify the accuracy with which observers can judge when a glare source reduces their visual acuity.

Drivers' judgments of the effect of headlight glare on their ability to see pedestrians at night.

Introduction: Several studies have concluded that pedestrians typically overestimate their own conspicuity to approaching drivers at night. The present experiments extended this research by exploring the accuracy of drivers' judgments of pedestrian conspicuity while facing varying degrees of headlight glare.

Method: In Experiment 1, participants on an open road estimated their ability to see a roadside pedestrian in each of two clothing configurations and with each of three different glare intensities present.

The accuracy of drivers' judgments of the effects of headlight glare on their own visual acuity.

Drivers' judgments of the magnitude of disability glare caused by high-beam headlights may not match actual declines in visual performance. This study investigated younger and older drivers' beliefs about their own visual performance in the presence of headlight glare. Eleven older drivers and seventeen younger drivers judged the distance at which they would just be able to recognize the orientation of a white Landolt C if it were present adjacent to the headlamps of a stationary opposing vehicle at night.

Pedestrians' estimates of their own nighttime conspicuity are unaffected by severe reductions in headlight illumination.

Introduction: At night pedestrians tend to overestimate their conspicuity to oncoming drivers, but little is known about factors affecting pedestrians' conspicuity estimates. This study examines how headlamp intensity and pedestrians' clothing influence judgments of their own conspicuity.

Method: Forty-eight undergraduate students estimated their own conspicuity on an unilluminated closed road by walking in front of a stationary vehicle to the point at which they judged that they were just recognizable to the driver.