Single fibers of cat optic nerve: "thresholds" to light.

Absolute thresholds of 39 single fibers of the optic nerves of 20 cats were determined by inspection of post-stimulus time histograms, each com puted from the responses to 60 to 100 identical flashes of white light. The values found-from 1.1 x 10(-7) to 6.8 x 10(-6) candella per square meter (nits)-agree well with psychophysi cal thresholds found in previous in vestigations.