Lauren Sigda¹, William Tuten¹; ¹University of California, Berkeley

Illusory motion can be perceived in a stationary stimulus following adaptation to circumjacent dynamic noise (Murakami and Cavanagh, 1998). This phenomenon, known as the jitter aftereffect (JAE), indicates image-based mechanisms play a role in generating a stable percept from the moving retinal image. Previous computational work proposed such perceptual stabilization mechanisms also contribute to resolving fine spatial details (Burak et al, 2010). We examined whether visual acuity is influenced by viewing conditions known to induce the JAE. Using a 60-Hz adaptive optics ophthalmoscope, we measure foveal visual acuity in 8 subjects. Diffraction-limited, tumbling-E optotypes (λ=680 nm) were superimposed on a circular gray background (diameter: 1.25°) provided by an external display. The central uniform disk was surrounded by an inner annulus (diameter: 4°) containing a static array of 2D Gaussian elements (σ: 8') and an outer annulus (diameter: 17°) composed of a binary noise texture with square elements subtending 8'. The boundary between each background zone was spatially blurred. Prior to testing, subjects adapted to dynamic (60 Hz) or static (0 Hz; control) noise in the outer annulus for 30 seconds. Stimuli were delivered for either 100 or 750 ms in a 1-second trial interval during which the background was static. A 6-second top-up adaptation period was inserted between each trial. As expected, the minimum angle of resolution improved with increasing exposure duration (mean±STD: 0.90±0.15 arcmin at 100 ms; 0.66±0.11 arcmin at 750 ms). At 750 ms, no systematic difference between test and control acuity was observed (signed-rank statistic: 16; p=0.844). At 100 ms, visual acuity exhibited a modest improvement in 7 of 8 subjects following exposure to dynamic random noise, though this effect was not significant (signed-rank statistic: 4; p=0.055). Our findings suggest, under the conditions studied, that the mechanisms perturbed during the JAE are not required for high-resolution vision.

Acknowledgements: This work was supported by the Air Force Office of Scientific Research (FA9550-20-1-0195, FA9550-21-1-0230), the National Institutes of Health (R01EY02359, T32EY007043), the Hellman Fellows Fund, and the Alcon Research Institute.