We hypothesized that older, neurologically normal drivers would compensate appropriately for their slower abilities by choosing larger gaps when entering traffic. To test this we used an instrumented vehicle and radar gun to study 18 legally licensed, neurologically normal drivers ranging from 22 to 72 years old. Drivers were asked to press a button to mark the last possible moment they would cross the road in front of an oncoming vehicle. We measured speed and distance of the oncoming vehicles

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... and calculated time-to-contact (TTC). The older drivers made more conservative gap acceptance decisions based on higher TTC than younger drivers. This pilot study identified trends in effects of age upon traffic entry judgments, suggesting that neurologically normal older drivers are more conservative when deciding to enter traffic than younger drivers.