Exploring Drivers' Situation Awareness in a Dynamic Traffic Environment

The change detection paradigm was used in a single-monitor driving simulator to study drivers' awareness of other vehicles on the roadway. While driving, a moving or parked vehicle ahead (30 or 60 m) would occasionally change location (30% or 60% nearer or farther away), color, or identity during a 150 ms blank-out period. The results showed that only for moving vehicles with a very large location displacement (60%) can the participants detect changes as well as with the color or identity change. We also examined how the driving task itself influences the formation of this representation; overall, the detection performance was better in the non-driving condition. We argue that vehicle location is coarsely represented in drivers' memory, and that this, together with vehicle features, is used to visually monitor more finegrained location information. This helps explain why drivers often fail to notice a decreasing distance to the car ahead, resulting in rear-end collisions.