The Effect of Retinal Eccentricity on Perceiving Collision Impacts

Abstract

Three experiments examined the role of central and peripheral vision in collision detection and control of braking. Displays simulated observer movement over a ground plane toward obstacles lying in the observer's path (Experiments 1 & 3) or toward a vertical 2-D plane (Experiment 2). Optical expansion was depicted under the constraint that remains constant throughout the approach. Displays employed in Experiments 1 and 2 were masked centrally (peripheral vision) or peripherally (central vision) with mask size ranging from 10° to 30° in diameter in steps of 5°. Participants responded to the optical pattern engendered by with more consistency in the peripheral vision condition than in the central vision condition. Experiment 3 further examined the peripheral advantage by masking the displayed peripheral region from 20% to 80%. Largely unaffected performance across masked areas of the periphery confirmed that the efficacy of the peripheral retina does not lie in more extensive flow vectors but in its inherent sensitivity to optical consequences engendered by . These results were compared with psychophysical findings in self-motion perception and clinical findings in patients with partial vision loss.

Notes

¹See Footnote 3 of Kim (2008) for issues concerning binocular viewing of monocular displays depicting motion in a 3-D environment.

²The effects of velocity and/or optical expansion rate have been reported frequently in most of the TTC and/or optical looming studies with displays stimulating the central visual field. See, for example, Michaels, Zeinstra, and Oudejans (2001) or Smith, Flach, Dittman, and Stanard (2001).

³This observation was discussed earlier in terms of perceptual boundaries between “no collision” and “collision” where the transitions between these two responses drifted in the central vision condition but remained constant in the peripheral vision condition.