TY - JOUR
T1 - Orientation-selective adaptation and tilt after-effect from invisible patterns
AU - He, Sheng
AU - MacLeod, Donald I.A.
PY - 2001/5/24
Y1 - 2001/5/24
N2 - Exposure to visual patterns of high contrast (for example, gratings formed by alternating white and black bars) creates after-effects in perception. We become temporarily insensitive to faint test patterns that resemble the pre-exposed pattern (such as gratings of the same orientation), and we require more contrast to detect them. Moreover, if the test pattern is slightly tilted relative to the pre-exposed one, this tilt may be perceptually exaggerated: we experience a tilt after-effect. Here we show that these visual after-effects occur even if the pre-exposed grating is too fine to be perceptually resolved. After looking at a very fine grating, so high in spatial frequency that it was perceptually indistinguishable from a uniform field, observers required more contrast to detect a test grating presented at the same orientation than one presented at the orthogonal orientation. They also experienced a tilt after-effect that depended on the relation of the test pattern's tilt to the unseen orientation of the pre-exposed pattern. Because these after-effects are due to changes in orientation-sensitive mechanisms in visual cortex, our observations imply that extremely fine details, even those too fine to be seen, can penetrate the visual system as far as the cortex, where they are represented neurally without conscious awareness.
AB - Exposure to visual patterns of high contrast (for example, gratings formed by alternating white and black bars) creates after-effects in perception. We become temporarily insensitive to faint test patterns that resemble the pre-exposed pattern (such as gratings of the same orientation), and we require more contrast to detect them. Moreover, if the test pattern is slightly tilted relative to the pre-exposed one, this tilt may be perceptually exaggerated: we experience a tilt after-effect. Here we show that these visual after-effects occur even if the pre-exposed grating is too fine to be perceptually resolved. After looking at a very fine grating, so high in spatial frequency that it was perceptually indistinguishable from a uniform field, observers required more contrast to detect a test grating presented at the same orientation than one presented at the orthogonal orientation. They also experienced a tilt after-effect that depended on the relation of the test pattern's tilt to the unseen orientation of the pre-exposed pattern. Because these after-effects are due to changes in orientation-sensitive mechanisms in visual cortex, our observations imply that extremely fine details, even those too fine to be seen, can penetrate the visual system as far as the cortex, where they are represented neurally without conscious awareness.
UR - http://www.scopus.com/inward/record.url?scp=0035942735&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0035942735&partnerID=8YFLogxK
U2 - 10.1038/35078072
DO - 10.1038/35078072
M3 - Article
C2 - 11373679
AN - SCOPUS:0035942735
SN - 0028-0836
VL - 411
SP - 473
EP - 476
JO - Nature
JF - Nature
IS - 6836
ER -