Exchange thresholds for long-wavelength incremental flashes.

A Reeves

doi:10.1364/josa.72.000565

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Exchange thresholds for long-wavelength incremental flashes.

A Reeves

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Abstract

Thresholds of 1-deg, 200-msec, 641-nm foveal test flashes rise after an exchange of II5-equated 536- and 626-nm fields, taking about 30 sec to recover. Silent substitution (no rise of threshold after the exchange) occurs, however, if these fields are alternated during adaptation. Thresholds for a 1-deg, 20-msec test rise similarly after an exchange but recover in only 0.5 sec and are not influenced by alternation of the 536- and 626-nm fields. These results can be accounted for if the 641-nm tests are detected not through pathways controlled by long-wavelength cones alone but through nonopponent (20-msc) and opponent (200-msec) pathways whose sensitivities may be reduced by transient inputs from other cones.

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A Reeves. 1982. Exchange thresholds for long-wavelength incremental flashes.. https://doi.org/10.1364/josa.72.000565

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