Perceptual saccadic suppression starts in the retina

Saad Idrees,Ziad M Hafed,Thomas A Münch,Felix Franke,Matthias P Baumann

doi:10.1038/s41467-020-15890-w

Abstract

Visual sensitivity, probed through perceptual detectability of very brief visual stimuli, is strongly impaired around the time of rapid eye movements. This robust perceptual phenomenon, called saccadic suppression, is frequently attributed to active suppressive signals that are directly derived from eye movement commands. Here we show instead that visual-only mechanisms, activated by saccade-induced image shifts, can account for all perceptual properties of saccadic suppression that we have investigated. Such mechanisms start at, but are not necessarily exclusive to, the very first stage of visual processing in the brain, the retina. Critically, neural suppression originating in the retina outlasts perceptual suppression around the time of saccades, suggesting that extra-retinal movement-related signals, rather than causing suppression, may instead act to shorten it. Our results demonstrate a far-reaching contribution of visual processing mechanisms to perceptual saccadic suppression, starting in the retina, without the need to invoke explicit motor-based suppression commands.

Highlights

Visual sensitivity, probed through perceptual detectability of very brief visual stimuli, is strongly impaired around the time of rapid eye movements
Perceptual saccadic suppression depends on image content
Coarse and fine textures had blobs that approximated the sizes of retinal ganglion cell (RGC) or retinal bipolar cell receptive fields, respectively, at the retinal flash locations[36] (Methods)

Summary

Introduction

Visual sensitivity, probed through perceptual detectability of very brief visual stimuli, is strongly impaired around the time of rapid eye movements. We show instead that visualonly mechanisms, activated by saccade-induced image shifts, can account for all perceptual properties of saccadic suppression that we have investigated Such mechanisms start at, but are not necessarily exclusive to, the very first stage of visual processing in the brain, the retina. The early visual system, including the retina, is a highly sensitive light sensing device, and can capture visual transients associated with saccade-induced retinal image shifts. Such early processing of visual transients could modulate the retinal output, jumpstarting an image processing cascade to mediate perceptual suppression. We asked: how much of the characteristics of perceptual saccadic suppression can be explained by visualonly mechanisms? And, to the extent that there are visual-only mechanisms, would the first neural locus for them be the very first stage of visual processing in the brain, the retina?

Methods

Results

Conclusion