Does daytime running lights increase or decrease visual contrast between vehicles and their backgrounds?

Daytime running lights (DRLs) generally increase visual contrast between vehicles and their backgrounds, making vehicles more noticeable to other drivers and pedestrians. By illuminating the front of the vehicle, DRLs enhance visibility in various lighting conditions, helping to reduce the chance of collisions. This increased contrast can be particularly beneficial in bright daylight or against complex backgrounds. Overall, DRLs contribute to improved road safety by enhancing vehicle detection.