The Effects of Near and Far Visual Occlusion upon a Simulated Driving Task

There is a growing body of evidence to suggest that steering behavior during driving can be described as two separate functions: one based upon closed-loop sampling of near-range visual information and the other based upon an open-loop anticipatory utilization of far-range visual cues. Past research has been performed using diagnostic measures of steering performance that may not be ideal for the separate measurement of these different mechanisms mediating driver steering performance. Through the use of a visual occlusion technique to isolate the availability of near-range versus far-range visual information, the proposed study hoped to demonstrate that RMS error and time-to-line crossing (TLC) statistics represent relatively independent measures of the near-range and far-range visual processes, respectively. Results of this investigation supported the idea that near-range visual processes are indexed by RMS error measurements but failed to find evidence supporting the idea of a separate far-range visual system for anticipatory maneuvers using time-to-line-crossing (TLC) as a measure.