Dynamic monitoring of traffic flow: The driver's situation awareness

A study was conducted to explore the potential of a new research method, the Change Blindness Paradigm, for investigating one aspect of drivers' situation awareness: their mental representation of nearby vehicles on the roadway. As 13 experienced drivers drove in a high-fidelity, single-monitor driving simulator, occasionally the location of a vehicle in the road ahead or one of its properties (its color or type) would suddenly change. Sometimes, in a blocked design, the change occurred during a brief (150 ms) blanking of the screen and sometimes there was no blank. Blanking the screen eliminates local stimulus cues that normally accompany change, so detection must be based on memory. All changes were well detected in the No-blank condition. In the Blank condition, detection of location change was near zero, while detection of color and identity change remained quite good. We argue that vehicle location is coarsely represented in drivers' memory, and that this, together with vehicle features, is used to visually monitor more fine-grained location information.