The discrimination of heading from optic flow is not retinally invariant

Abstract

Three experiments were conducted to determine whether the discrimination of heading from optic flow is retinally invariant and to determine the importance of acuity in accounting for heading eccentricity effects. In the first experiment, observers were presented with radial flow fields simulating forward translation through a three-dimensional volume of dots. The flow fields subtended 10°of visual angle and were presented at 0°, 10°,20°, and 40°of retinal eccentricity. The observers were asked to indicate whether the simulated movement was to the right or the left of a target that appeared at the end of the display sequence. Eye movements were monitored with an electrooculogram apparatus. In a second experiment, static acuity thresholds were derived for each of the observers at the same retinal eccentricities. There was a significant increase in heading detection thresholds with retinal eccentricity (from 0.92°at 0°retinal eccentricity to 3.47°at 40°).An analysis of covariance indicated that the variation in sensitivity to radial flow,as a function of retinal eccentricity, is independent of acuity. Similar results were obtained when the Vernier acuity of observers was measured. These results suggest that the discrimination of heading from radial flow is not retinally invariant.

Large Displays Enhance Optical Flow Cues and Narrow the Gender Gap in 3-D Virtual Navigation

“…Various researchers have claimed that given optical flow, only the central visual field is necessary for accurate judgments of heading and velocity (Atchley & Andersen, 1999;Crowell & Banks, 1993;Warren & Kurtz, 1992). However, because these researchers were interested mainly in showing that optical flow cues were not constant across the retina, most of the studies relied mainly on standard computer displays with relatively small FOVs and did not document the utility of peripheral optical flow cues in cognitive map formation tasks.…”

Women go with the (optical) flow

“…Various researchers have claimed that, given optical flow, only the central visual field is necessary for accurate judgments of heading and velocity [3,7,36,37]. However, most of these studies relied mainly on standard computer displays with relatively small fields of view.…”

Distinct visual motion processing impairments in aging and Alzheimer’s disease

“…Declines in motion coherence, created by the addition of random motion, impairs the processing of such stimuli [Zanker and Hupgens 1994]. Aging has been associated with increases in optic flow heading thresholds, thought to be attributable to declines in central visual processing [Warren, Jr. et al 1989] [Atchley and Andersen 1998] [Atchley and Andersen 1999]. However, comparison to other forms of visual motion processing have shown that optic flow perception is relatively resistant to the detrimental effects of both brain aging [Billino et al 2008] and focal cortical lesions [Billino et al 2009].…”