Suppression without inhibition: how retinal computation contributes to saccadic suppression.

Area of Science:

• Neuroscience
• Vision Science
• Retinal Physiology

Background:

• Visual perception is remarkably stable during saccadic eye movements, despite significant visual disruption.
• Saccadic suppression, a reduction in visual sensitivity originating in the retina, contributes to this stability.
• The precise retinal circuit mechanisms underlying saccadic suppression remain largely unknown.

Purpose of the Study:

• To elucidate the retinal circuit mechanisms responsible for saccadic suppression.
• To investigate how the retina processes sequential visual stimuli during eye movements.

Main Methods:

• Electrophysiology in mouse, pig, and macaque retinas.
• Two-photon calcium imaging.
• Computational modeling and human psychophysics.

Main Results:

• Three independent suppressive mechanisms were identified in the retina triggered by sequential stimuli.
• The primary mechanism involves temporal filtering and downstream nonlinearities in cone photoreceptors, not inhibition or adaptation.
• Two additional mechanisms, primarily affecting ON ganglion cells, originate in the receptive field surround.

Conclusions:

• These findings reveal novel retinal circuit mechanisms contributing to saccadic suppression.
• The uncovered mechanisms are crucial for maintaining visual stability during natural viewing conditions involving eye movements.
• Disparities in suppression mechanisms between ON and OFF retinal ganglion cells were highlighted.