We have an emerging understanding of how retinal circuits work in starlight, when rods dominate retinal inputs, and daylight, when cones dominate retinal inputs. We know much less about how the retina works when rods and cones are coactive?as they are from moonlight to dawn or dusk. Interactions between rod and cone signals under these conditions shape the temporal, chromatic and spatial acuity of vision. Because rod- and cone-derived signals converge upon the same retinal output cells, interactions between these signals are very likely to play a substantial role in shaping perception. The broad goal of our work is to understand the mechanisms that dictate how rod- and cone-mediated signals interact to control retinal outputs and perception. We will focus on three questions: (1) What routes do rod-derived signals take through the primate retina, and does the route depend on light level? (2) Do rod and cone signals adapt independently or are there shared adaptational mechanisms? (3) What circuit mechanisms control integration of time-varying rod and cone signals and what are the consequences for the retinal output and perception? We will answer these questions using electrophysiological recordings of responses from all major cells types in primate retina. Similar issues arise in many other neural circuits; thus, the proposed work will improve our general understanding of neural function.

Public Health Relevance

The ability of rod photoreceptors to detect single photons has helped make rod phototransduction the best understood of the many G-protein cascades in biological systems and has led to direct medical bene?ts. We know much less about the retinal readout of rod and cone signals, particularly under conditions (such as dawn or dusk) when both rods and cones are active and reliable vision is challenging. These lighting conditions span about 30% of the operational range of vision, and include a number of situations, such as night driving, under which vision is essential. The long-term aim of the work described here is to help ?ll this gap in our knowledge, speci?cally in primate retina where we can make a direct connection with human perception and disease.

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Research Project (R01)
Project #
5R01EY028111-04
Application #
9965933
Study Section
Neurotransporters, Receptors, and Calcium Signaling Study Section (NTRC)
Program Officer
Greenwell, Thomas
Project Start
2017-09-01
Project End
2022-06-30
Budget Start
2020-07-01
Budget End
2021-06-30
Support Year
4
Fiscal Year
2020
Total Cost
Indirect Cost
Name
University of Washington
Department
Physiology
Type
Schools of Medicine
DUNS #
605799469
City
Seattle
State
WA
Country
United States
Zip Code
98195
Rivlin-Etzion, Michal; Grimes, William N; Rieke, Fred (2018) Flexible Neural Hardware Supports Dynamic Computations in Retina. Trends Neurosci 41:224-237
Grimes, William N; Songco-Aguas, Adree; Rieke, Fred (2018) Parallel Processing of Rod and Cone Signals: Retinal Function and Human Perception. Annu Rev Vis Sci 4:123-141
Grimes, William N; Baudin, Jacob; Azevedo, Anthony W et al. (2018) Range, routing and kinetics of rod signaling in primate retina. Elife 7: