Effects of differences in vision upon drivers’ spatial cognition:: Focus on the subjective and objective viewpoints

To support spatial cognition by drivers, it is becoming common for cameras and monitors to be attached to automobiles to enable drivers to see perspectives (objective viewpoints) besides their own field of vision (subjective viewpoint). Previous studies have suggested that the difference between the subjective and objective viewpoints influences drivers’ spatial cognition of their automobiles; however, the specific impacts on the human cognitive process of recognizing space, and on driving performance, have yet to be revealed. Thus, this study was designed to experimentally assess the role of subjective and objective viewpoints in the cognitive process of driving and the level of driving performance. The following results were obtained: (1) driving behavior with a subjective viewpoint tends to be more careful, as demonstrated by the rate of collision with dynamic objects. It was shown that a high cognitive load was applied in this case, but that subjective fatigue was small. It was thought that the subjective viewpoint makes a sense of ownership occur more readily than the objective viewpoint, so drivers tried to avoid collision by unconsciously recognizing their cars as part of themselves. (2) Driving with an objective viewpoint tended to be smoother, as evidenced by the frequency of collision with a wall. In addition, the cognitive load was also low.