Aislin A. Sheldon¹ (), Samantha A. Montoya^2,3, Anna J. Hillstrom⁴, Hannah R. Moser¹, Tylyn A. Page¹, Carter B. Mulder¹, Abby I. Metzler⁵, Carrie E. Robertson⁶, Michael S. Lee⁷, Stephen A. Engel⁴, Michael-Paul Schallmo¹; ¹Department of Psychiatry and Behavioral Sciences, University of Minnesota, Minnesota, ²Graduate Program in Neuroscience, University of Minnesota, Minnesota, ³Perelman School of Medicine, University of Pennsylvania, Philadelphia, ⁴Department of Psychology, University of Minnesota, Minnesota, ⁵Department of Neurology, University of Minnesota, Minnesota, ⁶Department of Neurology, Mayo Clinic, Rochester, Minnesota, ⁷Department of Ophthalmology and Visual Neurosciences, University of Minnesota, Minnesota

Visual snow syndrome (VSS) is a neurological disorder involving persistent flickering static seen across the whole visual field. VSS can interfere with daily living tasks, and the estimated prevalence is ~2% of the population. Effective treatments are limited and the neural basis is unknown. In particular, it is unclear where in the visual system the snow percept is generated. Using adaptation to dynamic noise, it has been shown that snow percepts were attenuated on the side of the display where the adapter was presented (Montoya et al, 2023). To test the spatial tuning of adaptation affecting visual snow, in this experiment we used an adaptation task that included two dynamic noise gratings: vertically oriented on one side and horizontal on the other, with contrast modulated sinusoidally over space. The wavelength of adapter gratings varied across trials. If visual snow is retinotopic, we predicted that adaptation would produce oriented bands of attenuated snow, and participants with VSS were instructed to respond when they no longer perceived attenuated stripes of snow. We expected that if the adapter wavelength was smaller than the adapted neuronal receptive fields, both left and right circles would be uniformly adapted, and participants would respond immediately. In initial testing, participants with VSS responded almost immediately for adapters with shorter wavelengths (≤ 0.5°), and reported that the percept of snow was reduced uniformly across the entire adapter region (i.e., no stripes). Adapters with longer wavelengths produced stripes of attenuated snow for greater durations. This supports the hypothesis that the neural activity underlying visual snow is retinotopic, and that adaptation of snow operates on a spatial scale up to ~ 0.5°. Our findings may help identify neural populations that participate in generating the percept of visual snow, based on their receptive field properties.

Acknowledgements: R01 EY036005, P41 EB015894, UL1 TR002494, and the President’s Postdoctoral Fellowship Program, University of Minnesota.