期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1990
卷号:87
期号:5
页码:1860-1864
DOI:10.1073/pnas.87.5.1860
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:The signals in neighboring cones are partially correlated due to local correlations of luminance in the visual scene. By summing these partially correlated signals, the retinal ganglion cell improves its signal/noise ratio (compared to the signal/noise ratio in a cone) and expands the variance of its response to fill its dynamic range. Our computations prove that the optimal weighting function for this summation is dome-shaped. The computations also show that (assuming a particular space constant for the correlation function) ganglion cell collecting area and cone density are matched at all eccentricities such that the signal/noise ratio improves by a constant factor. The signal/noise improvement factor for beta ganglion cells in cat retina is about 4.