Shift of attention in depth in a semi-realistic setting

Abstract

This research was based on previous research on the useful field of view in real driving, however shift of attention was examined in depth by the use of an improved tunnel simulator. Despite of the importance of this area of research, nothing like this has been performed previously. The subjects' task was judgment of the relative distance of targets (farther, nearer, or the same), in comparison with a fixation point. Reaction times were measured. There were two variables. One was three observing conditions. Subjects moved at apparent speeds of 40 km/h or 80 km/h or were stationary. The second variable was the validity of the precue concerning the location of the appearance of the target relative to the fixation point. There were three conditions, valid, invalid and or neutral. The results clearly showed that reaction times for nearer targets were shorter than those for farther targets in all conditions. This supports a viewer-centered representation of three-dimensional space. Concerning the direction of shift of attention, reaction time for shift of attention from far locations to near locations was shorter than for the opposite. This difference was more remarkable in the moving condition than in the stationary condition. This was called the rubber band metaphor of attention in locomotion (asymmetrical viewer-centered mode of shift of attention in depth). These results are ecologically valid. Possible underlying mechanisms are discussed from the viewpoint of distribution of attention resource.