Abstract
Older drivers are known to look less often for hazards when turning at T-intersections or at four way intersections. The present study is an extension of Romoser & Fisher (2009) and attempts to further analyze the differences in scanning behavior between older and experienced younger drivers in intersections. We evaluated four hypotheses that attempt to explain the older drivers' failure to properly scan in intersections: difficulty with head movements, decreases in working memory capacity, increased distractibility, and failure to recall specific scanning patterns. To test these hypotheses, older and younger experienced drivers' point-of-gaze was monitored while they drove a series of simulated intersections with hidden hazards outside of the turning path. Our results suggest that none of these hypotheses can fully explain our finding that older adults are more likely to remain fixated on their intended path of travel and look less than younger drivers towards other areas where likely hazards might materialize. Instead, the results support a complementary hypothesis that at least some of the difficulties older adults have scanning intersections are due to a specific attentional deficit in the older drivers' ability to inhibit what has become their prepotent goal of monitoring the vehicle's intended path of travel, thereby causing older drivers to fail to scan hazardous areas outside this intended path of travel.