Auto Safety: How To Pass Other Vehicles

by Rob Gray, Ph.D. & David Regan, Ph.D.

Overtaking and passing other cars is considered one of the more dangerous situations facing drivers.

Research based on driving simulations suggests that staring at the road while driving at a high-speed may put drivers at greater risk for rear-end collisions when they attempt to overtake and pass another car.

Focusing on the road in front of your car for too long can be hazardous say psychologist and lead author Rob Gray, Ph.D., of Nissan Cambridge Basic Research and co-author psychologist David Regan, Ph.D., of York University.

"Motion adaptation - which is a change in the motion-detecting cells in your brain produced by prolonged viewing of moving objects - can occur when driving on a straight empty road. This can have detrimental effects on visually guided motor actions such as overtaking another car and can lead to a fatal error."

"For example, when driving straight ahead on an empty highway, a driver's visual image continuously expands and objects such as the road markings and trees continually move past our eyes. As the driver continues to drive and gets closer to the trees, the image of the trees keep getting bigger and bigger. The trees actually move from the center of the driver's windshield towards the edge of the windshield until they disappear out of view.

When we look at something that always moves in the same way it causes the motion-detecting cells in our brain to adapt to that motion," explains Dr. Gray.

In our study, we examined the effects of motion adaptation -produced by driving on a virtual highway - on overtaking maneuvers in a driving simulator. Eighteen 19- to 36-year-old experienced drivers participated, said Dr. Gray.

The driving simulator consisted of the frontal two-thirds of a Nissan 240SX convertible and a wide-field-of-view (60 degrees horizontal X 40 degrees vertical) display of a simulated driving scene. It provided realistic feedback through the torque in the steering wheel and audio feedback consisting of engine noise that increased with faster car speeds, according to the study.

Following five minutes of driving on a straight empty highway, drivers initiated overtaking of other vehicles substantially later (by 0.2-0.5 seconds) than comparable maneuvers made following five minutes of driving on a winding country road, said the authors.

"This delay in the initiation of overtaking appears to be caused by an overestimation of the time to collision with the lead vehicle (i.e. the driver has the illusion that she/he has more time before a collision will occur) caused by motion adaptation. To make matters worse, we also found that motion adaptation caused our participants to drive considerably faster (by 5 mph on average)."

Reference:

"Risky Driving Behavior: A Consequence of Motion Adaptation for Visually Guided Motor Action," Rob Gray, Ph.D., Nissan Cambridge Basic Research and David Regan, Ph.D.; Journal of Experimental Psychology: Human Perception and Performance, Vol. 26, No. 6.

This information received from the American Psychological Association (APA), in Washington, DC.