Space-time codependence of retinal ganglion cells can be explained by novel and separable components of their receptive fields.
Reverse correlation methods such as spike-triggered averaging consistently identify the spatial center in the linear receptive fields (RFs) of retinal ganglion cells (GCs). However, the spatial antagonistic surround observed in classical experiments has proven more elusive. Tests for the antagonistic surround have heretofore relied on models that make questionable simplifying assumptions such as space-time separability and radial homogeneity/symmetry. We circumvented these, along with other common assumptions, and observed a linear antagonistic surround in 754 of 805 mouse GCs. By characterizing the RF's space-time structure, we found the overall linear RF's inseparability could be accounted for both by tuning differences between the center and surround and differences within the surround. Finally, we applied this approach to characterize spatial asymmetry in the RF surround. These results shed new light on the spatiotemporal organization of GC linear RFs and highlight a major contributor to its inseparability.
Department of Ophthalmology, Baylor College of Medicine, Houston, Texas Department of Neuroscience, Baylor College of Medicine, Houston, Texas.
Cameron S
CS
Cowan
Department of Ophthalmology, Baylor College of Medicine, Houston, Texas Department of Neuroscience, Baylor College of Medicine, Houston, Texas Medical Scientist Training Program, Baylor College of Medicine, Houston, Texas sabharwa@bcm.edu.
Jasdeep
J
Sabharwal
Department of Ophthalmology, Baylor College of Medicine, Houston, Texas Department of Neuroscience, Baylor College of Medicine, Houston, Texas.
Samuel M
SM
Wu
D000200:Action Potentials; D000818:Animals; D004594:Electrophysiology / Q000379:methods; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008959:Models, Neurological; D010775:Photic Stimulation / Q000379:methods; D012160:Retina / Q000502:physiology; D012165:Retinal Ganglion Cells / Q000502:physiology*; D013028:Space Perception; D062206:Spatial Analysis; D062211:Spatio-Temporal Analysis; D013995:Time; D014785:Vision, Ocular; D014796:Visual Perception / Q000502:physiology*
Retinal ganglion cells; space–time separability; spatiotemporal tuning