Background light and the contrast gain of primate P and M retinal ganglion cells.

Rockefeller University, New York, NY 10021-6399.
Proceedings of the National Academy of Sciences (Impact Factor: 9.81). 07/1988; 85(12):4534-7. DOI: 10.1073/pnas.85.12.4534
Source: PubMed

ABSTRACT Retinal ganglion cells projecting to the monkey lateral geniculate nucleus fall into two classes: those projecting to the magnocellular layers of the nucleus (M cells) have a higher contrast gain to luminance patterns at photopic levels of retinal illumination than those projecting to the parvocellular layers (P cells). We report here that this difference in luminance contrast gain between M and P cells is maintained at low levels of mean retinal illumination. In fact, our results suggest that in the mesopic and scotopic ranges of mean illumination, the M-cell/magnocellular pathway is the predominant conveyor of information about spatial contrast to the visual cortex.


Available from: Ehud Kaplan, Apr 19, 2015
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