Abstract
Older drivers have an increased rate of automobile crashes per kilometer driven, likely due in part to age-related declines in motion perception. Our research group has developed the "Peripheral Motion Contrast Threshold test" (PMCT) test and, more recently, the "Rapid PMCT" test as measures of peripheral motion sensitivity. Results from these tests have been shown to correlate strongly with indicators of driving performance in older individuals. In the current study, we investigated how effective the PMCT and RPMCT tests are at predicting driving safety on a driving simulator. We tested 26 younger drivers and 26 older drivers in the STISIM high fidelity driving simulator. Performance was measured in terms of number of collisions and minimum distance of approach to hazards. The PMCT presents participants with Gabors (0.4 cpd, 13.75°/s drift) at one of four locations 15° from fixation, and uses method of limits to measure contrast threshold. The RPMCT presents the same stimuli positioned 15° to either side of fixation, and uses a 2AFC variation on the ascending Bekesy Method. Results from the older drivers show a positive correlation between PMCT & RPMCT and collision rate.. There was also a significant negative correlation between PMCT & RPMCT measures and minimum distance of approach to hazards. Our research demonstrates the ability of both measures to effectively predict the occurrence of hazardous driving under simulated conditions in older subjects.
Meeting abstract presented at VSS 2013