Perceptual Load in Central and Peripheral Regions and Its Effects on Driving Performance With and Without Collision Avoidance Warning System

A driving simulator study was conducted to test the influence of Collision Avoidance Warning System on drivers’ performance. Perceptual load on the road (e.g., vehicles’ congestion) and its sides (e.g., pedestrians’ number) were manipulated, while critical events occurred on the road (e.g., a leading car suddenly slowed down) or initiated from its sides (e.g., a pedestrian crossed the road unexpectedly). Each participant drove in four different scenarios: two with the warning system and two without. We found that at least in one condition (low levels of load in both regions) the system acted like a two-edged sword: On the one hand it decreased accidents with entities on the road, but on the other hand it increased accidents with entities arriving from the road sides. These findings demonstrate the importance of a systematic manipulation of perceptual load across the visual field and the critical events’ location when evaluating drivers’ behavior.