Fig. 4. ChrimsonR mediated responses can be recorded from cells that have lost their photoreceptor input, restoring light sensitivity.

a Confocal SLO image of GCaMP6s fluorescence in foveal RGCs pre-scotoma. 150 µm scale bar also applies to (c, e, f) and (k). b OCT image pre-scotoma 150 µm scale bar also applies to (d). c Confocal SLO image of GCaMP6s in foveal RGCs post-scotoma, lesion appears as dark region in the superior fovea. d OCT image post-scotoma showing damage to the photoreceptor layer. e Difference between images (a) and (c), highlighting the putative region of RGCs without photoreceptor input. f Pseudo-colored GCaMP6s image showing recording areas in the superior fovea with damaged photoreceptor input (pink) and inferior region with photoreceptor input intact (purple). g No periodic response to 0.2 Hz pan-retinal visual stimulus from 46 RGCs in superior region, indicating a loss of photoreceptor input. h Periodic response from 48 RGCs in the inferior imaging area, indicating normal photoreceptor input. i Temporal Fourier transform of data shown in (g) showing no response at 0.2 Hz consistent with loss of photoreceptor input. j Temporal Fourier transform of data in (h) showing a response at 0.2 Hz consistent with normal photoreceptor input. k As (f), with positions of spatially localized high power grating stimuli. l Fourier transform showing optogenetic RGC response to a 0.2 Hz spatially localized stimulus despite the loss of photoreceptor input. m Fourier transform showing optogenetic RGC response to a 0.2 Hz spatially localized stimulus. n Control, spatially localized constant mean luminance presented to the superior region, no periodic response at 0.2 Hz demonstrating the signal in (l) is dependent on the visual stimulus. This data was collected at a single time point using the maximum light budget available two weeks after photoreceptor ablation and therefore no repeat measurements could be performed in this case. Source data are provided as a Source Data file.