TY - JOUR
T1 - Visible flicker from invisible patterns
AU - MacLeod, Donald I.A.
AU - He, Sheng
PY - 1993
Y1 - 1993
N2 - USING a laser interferometer we can create grating patterns of high optical contrast (interference fringes) directly on the retina1-3. With coarse fringe patterns, the alternating light and dark bars of the pattern can be seen, but the bars of the finest fringes are not subjectively resolved. We report here that when we rapidly modulate the contrast of a fine fringe pattern (keeping overall luminance constant), observers experience flicker, even if the fringes are too finely spaced to be perceived as a grating. For this flicker to be seen, the pattern needs to be resolvable by the photoreceptors themselves, but not necessarily by later stages of visual processing. It can be explained if, in man, signals associated with individual cone receptors do not depend linearly on light intensity, but instead are scaled by a fast sensitivity-regulating or light-adaptation mechanism. Contrast-modulation flicker is not demonstrable in rod vision; rod vision therefore lacks such a local adaptation process.
AB - USING a laser interferometer we can create grating patterns of high optical contrast (interference fringes) directly on the retina1-3. With coarse fringe patterns, the alternating light and dark bars of the pattern can be seen, but the bars of the finest fringes are not subjectively resolved. We report here that when we rapidly modulate the contrast of a fine fringe pattern (keeping overall luminance constant), observers experience flicker, even if the fringes are too finely spaced to be perceived as a grating. For this flicker to be seen, the pattern needs to be resolvable by the photoreceptors themselves, but not necessarily by later stages of visual processing. It can be explained if, in man, signals associated with individual cone receptors do not depend linearly on light intensity, but instead are scaled by a fast sensitivity-regulating or light-adaptation mechanism. Contrast-modulation flicker is not demonstrable in rod vision; rod vision therefore lacks such a local adaptation process.
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U2 - 10.1038/361256a0
DO - 10.1038/361256a0
M3 - Article
C2 - 8423852
AN - SCOPUS:0027434357
SN - 0028-0836
VL - 361
SP - 256
EP - 258
JO - Nature
JF - Nature
IS - 6409
ER -