Asymmetric Activation of Retinal ON and OFF Pathways by AOSLO Raster-Scanned Visual Stimuli

Patterson, S. S.; Cai, Y.; Yang, Q.; Merigan, W. H.; Williams, D. R.

doi:10.1101/2024.12.17.628952

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bioRxiv · 10.1101/2024.12.17.628952

Asymmetric Activation of Retinal ON and OFF Pathways by AOSLO Raster-Scanned Visual Stimuli

Patterson, S. S.·Cai, Y.·Yang, Q.·Merigan, W. H.·Williams, D. R.

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Abstract

Adaptive optics scanning light ophthalmoscopy (AOSLO) enables high-resolution retinal imaging, eye tracking, and stimulus delivery in the living eye. AOSLO-mediated visual stimuli are created by temporally modulating the excitation light as it scans across the retina. As a result, each location within the field of view receives a brief flash of light during each scanner cycle (every 33-40 ms). Here we used in vivo calcium imaging with AOSLO to investigate the impact of this intermittent stimulation on the retinal ON and OFF pathways. Raster-scanned backgrounds exaggerated existing ON-OFF pathway asymmetries leading to high baseline activity in ON cells and increased response rectification in OFF cells.

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Patterson, S. S., Cai, Y., Yang, Q., Merigan, W. H., Williams, D. R.. 2024-12-17. Asymmetric Activation of Retinal ON and OFF Pathways by AOSLO Raster-Scanned Visual Stimuli. https://doi.org/10.1101/2024.12.17.628952

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