The effectiveness of glare-reducing glasses on simulated nighttime driving performance in younger and older adults

Glare from oncoming headlights is a problem for nighttime drivers because it can decrease visual acuity and cause discomfort. This diminished visual ability and discomfort due can increase drivers’ risk for traffic accidents. Older drivers experience more severe detrimental effects from nighttime glare, and these effects may pose a growing roadway hazard as the number of older drivers increases. The increased brightness of popular high-intensity-discharge (HID) headlights may further exacerbate these visibility problems. In a sample of younger (under 40 years of age) and older (40 years of age and older) drivers, we examined the impact of headlight glare from HID and traditional halogen lights on driving performance in a simulator, as well as the effectiveness of novel polarized glare-reducing eyeglasses for mitigating glare-induced performance deficits. The glare-reducing glasses increased visual awareness in the face of oncoming HID headlights compared to halogen headlights in both age groups. Older drivers performed significantly worse than did younger drivers on several measures of driving and visual detection performance. The glare-reducing glasses mitigated performance deficits, with older drivers performing similarly to younger drivers when exposed to HID headlights while wearing the polarized glasses. Due to the introduction of brighter LED-based headlights to the consumer automotive market and an expanding population of older drivers, automotive manufactures should consider glare-mitigation strategies when designing future headlight systems.