VISUAL SEARCH PROBLEMS AS CAUSATIVE FACTOR OF ACCIDENTS AT CROSSROADS

In Japan, many fatal accidents involving two vehicles at rural crossroads happen at intersections with good visibility, such as those located in rice field areas. The present study investigated a possible causative factor of these accidents from the point of visual search performance. One possible countermeasure to prevent these accidents was also examined. Two experiments were conducted using the advanced driving simulator of the Centre for Environmental and Traffic Psychology (University of Groningen). In the experiments typical sceneries of rice field intersections were projected on a 165 degrees horizontal screen. It has been found that a vehicle on collision course appears not to move but remains static in the other driver's peripheral visual field. In the first experiment, peripheral vision’s detection performance of both a vehicle on collision course, and of a vehicle not on collision course was studied. It was shown that a vehicle that is not on collision course can be easily detected. On the other hand, the detection of a vehicle on collision course was much more delayed especially when the object was further in the peripheral visual field. In the 2nd experiment, the effect of road side fences on the detection of a vehicle on collision course was studied. Fences were set along the roadside of the crossing path, making a vehicle on collision course abruptly appear from behind a fence. It was shown that the detection was earlier with fences compared to the without fences condition.