The effects of simulated vision impairments on the cone of gaze

Abstract

Detecting the gaze direction of others is critical for many social interactions. We explore factors that may make the perception of mutual gaze more difficult, including the degradation of the stimulus and simulated vision impairment. To what extent do these factors affect the complex assessment of mutual gaze? Using an interactive virtual head whose eye direction could be manipulated by the subject, we conducted two experiments to assess the effects of simulated vision impairments on mutual gaze. Healthy subjects had to demarcate the center and the edges of the cone of gaze, that is, the range of gaze directions accepted for mutual gaze. When vision was impaired by adding a semi-transparent white contrast reduction mask to the display (Exp. 1), judgments became more variable and more influenced by the head direction (indicative of a compensation strategy). When refractive blur was added (Exp. 1), the gaze cone shrank from 12.9° (no blur) to 11.3° (3-diopter len s), which cannot be explained by a low-level process but might reflect a tightening of the criterion for mutual gaze as a response to the increased uncertainty. However, the overall effects of the impairments were relatively modest. Elderly subjects (Exp. 2) produced more variability but did not differ qualitatively from the younger subjects. In the face of artificial vision impairments, compensation mechanisms and criterion changes allow us to perform better in mutual gaze perception than would be predicted by a simple extrapolation from losses in basic visual acuity and contrast sensitivity.

Quantifying the Wollaston Illusion

“…The actual horizontal gaze direction of a two-dimensional head may deviate by approximately 5° to the left or to the right before the impression of mutual gaze breaks down. This 10° range may be somewhat narrower when a 3D-head is used (Gamer & Hecht, 2007) or it can widen somewhat when the stimulus is degraded or visibility is poor (Hecht et al., 2015; Mareschal et al., 2013) or if the person alters the criterion for mutual gaze (Gamer et al., 2011).…”

Effect of Gaze on Personal Space: A Japanese–German Cross-Cultural Study

“…Could the downward gaze deflection by 10° not have been sufficiently strong to be perceived as averted? This seems unlikely as the vertical width of the cone of gaze is on the order of 12°, that is, 6° downward, such that a gaze deflection of 10° would be well outside this cone (regarding the robustness and shape of the gaze cone, see Hecht, Hörichs, Sheldon, Quint, & Bowers, 2015). Likewise, we can rule out that the use of pictures instead of real observers has failed to produce impressions of mutual versus downward gaze.…”

People With Central Vision Loss Have Difficulty Watching Videos

“…Some of what is known about the relationship between CVL and its effects on task performance comes from studies that have simulated vision impairment. Commonly used simulations include optical defocus (refractive blur),12–17 diffusive filters,17–22 and image blur (though image processing) 15,16,20–24. These may resemble the “initial stages of sudden onset, acquired visual loss”18 due to cataract, keratoconus, corneal scarring, or uncorrected refractive error in that their primary effect is a uniform reduction in image resolution across the visual field.…”

“…Optical defocus places objects at a depth plane that is out of focus on the retina 12–17. Studies that have used these simulations suggest that they may impair viewers comparably to those with low visual acuity and low vision for certain tasks 18,20–22,31. In the second study, we induced blur by using defocus lenses (refractive blur), which had been previously used to simulate impaired vision 12–17.…”