Identify types of RGCs that show dynamic computations and find triggers for these dynamics

The visually-induced functional switches are not restricted to direction selective ganglion cells. The ON and OFF retinal pathways that signal light increments and decrements, respectively, are well known for their segregate parallel processing. Yet, we and others find that subtypes of retinal cells can switch their polarity following repetitive stimulation or following changes in ambient light levels.

An RGC’s polarity preference changes with light illumination

Peri-stimulus time histograms (PSTHs) of transient-Off-alpha RGC in response to a dark spot at low (left) and high (right) light intensities (64 and 64x10⁴ R*/rod/sec, respectively; same contrast), revealing both On and Off responses in low illumination but only an Off response in high illumination. Dark bars indicate spot period.

Right: Z-stack projections (top) and side view (bottom) reveal morphology of the RGC.

We use two-photon calcium imaging and electrophysiology to determine the prevalence of retinal dynamic computing and identify types of RGCs that tend change their function. In addition, we explore the various conditions and dimensions over which retinal computations are dynamic.