Temporal structure in spiking patterns of ganglion cells defines perceptual thresholds in rodents with subretinal prosthesis.

摘要: Subretinal prostheses are designed to restore sight in patients blinded by retinal degeneration using electrical stimulation of the inner neurons. To relate output perception, we studied behavioral thresholds blind rats with photovoltaic subretinal stimulated full-field pulsed illumination at 20 Hz, and measured ganglion cell (RGC) responses similar stimuli ex-vivo. Behaviorally, exhibited startling response changes brightness, an average contrast threshold 12%, which could not be explained RGC spiking rate. However, RGCs millisecond-scale variations spike timing, even when rate did change significantly. At 12% temporal contrast, firing patterns prosthetic were as significant 2.3% steps visible light healthy retinas. This suggests that define perceptual vision. Response last pulse burst lasted longer than steady-state during burst. may interpreted excitatory OFF stimulation, can explain decrease illumination. Contrast enhancement images prior delivery prosthesis partially compensate for reduced sensitivity