‘The last channel’: Vision at the temporal margin of the field
Data files
May 08, 2020 version files 8.16 KB
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data_instructions.txt
948 B
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Experiment1.csv
5.95 KB
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Experiment2.csv
882 B
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Experiment3.csv
372 B
Abstract
The human visual field, on the temporal side, extends to at least 90 degrees from the line of sight. Using a two-alternative forced-choice procedure in which observers are asked to report the direction of motion of a Gabor patch, and taking precautions to exclude unconscious eye movements in the direction of the stimulus, we show that the limiting eccentricity of image-forming vision can be established with precision. There are large, but reliable, individual differences in the limiting eccentricity. The limiting eccentricity exhibits a dependence on log contrast; but it is not reduced when the modulation visible to the rods is attenuated, a result compatible with the histological evidence that the outermost part of the retina exhibits a high density of cones. Our working hypothesis is that only one type of neural channel is present in the far periphery of the retina, a channel that responds to temporally modulated stimuli of low spatial frequency and that is directionally selective.
For a description of how the data were collected and processed, please refer to the journal article.
A text file ('data_instructions.txt') is provided to clarify the contents of the data files ('Experiment1.csv', 'Experiment2.csv', 'Experiment3.csv').