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Patterson, S. S.

Publications and source records attributed to Patterson, S. S..

2 recordsLinked to original sources

The Spectral Sensitivity of Black and White

Our percepts of black and white are not equally strong for all monochromatic lights across the spectrum, but instead have a spectral tuning defined by they ways in which their neural substrates process the outputs of three univariant cone photoreceptors. The neurons mediating black and white and how they combine the cone outputs remain controversial but growing evidence indicates cone-opponent midget ganglion cells are involved. The paradoxical implications of having "chromatic" neurons mediate what is traditionally assumed to be a role of "achromatic" neurons remain unresolved. Here, we investigate whether midget ganglion cells can account for the variation in perceived saturation with wavelength.

neuroscience

An S-cone circuit for edge detection in the primate retina

Midget retinal ganglion cells (RGCs) are the most common RGC type in the primate retina. Their responses mediate both color and spatial vision, yet the specific links between midget RGC responses and visual perception are unclear. Previous research on the dual roles of midget RGCs has focused on those comparing long (L) vs. middle (M) wavelength sensitive cones. However, there is evidence for several other rare midget RGC subtypes receiving S-cone input, but their role in color and spatial vision is uncertain. Here, we confirm the existence of the single S-cone center OFF midget RGC circuit in the central retina of macaque monkey both structurally and functionally, by combining single cell electrophysiology with 3D electron microscopy reconstructions of the upstream circuitry. Like the well-studied L vs. M midget RGCs, the S-OFF midget RGCs have a center-surround receptive field consistent with a role in spatial vision. While spectral opponency in a primate RGC is classically assumed to contribute to hue perception, a role supporting edge detection is more consistent with the S-OFF midget RGC receptive field structure and studies of hue perception.

neuroscience