The Effect of Driver Age on Scanning Behaviors in Risky Situations

In 2002, older drivers 70 and above had higher rates of fatal crashes than any other group except for young novice drivers and accounted for 12% of al1 fatal accidents. These fatal crash rates rise sharply with increasing age. A number of studies have indicated that the high crash rate is associated with decreases in useful field of view. One of the consequences of this decrease might be a corresponding decrease in older adult’s ability to attend to information in the periphery that is relevant to identifying real and potential risks and at the same time to attend to information in the road ahead necessary to maintain lane position, among other things. Thus, they may scan the roadway to the sides for risks which are not visible less often as they age. This hypothesis that as adults age they scan the roadway to the sides less selectively for potential risks was evaluated on a fixed-base driving simulator, using eye movements to index whether adults 60 years old and older were increasingly less likely to attend to information that signals potential risks. Contrary to hypothesis, the results show that overall old-old drivers (75-79) scan risky areas in the periphery more often than middle-aged (40-50) and middle-old drivers (70-74), but just as often as young-old (60-69) drivers. An eye movement analysis explains these surprising results by indicating that old-old drivers are simply scanning areas of the roadway that do not require much of their attention more frequently than middle-age drivers. It appears that the old-old drivers are compensating for a loss in their useful field of view, but not doing so strategically. That is, old-old drivers are not selecting, dividing or sustaining attention well enough to selectively scan the environment, accurately predict risks and plan appropriate defensive driving maneuvers.