Open AccessSensitivity and perceptual awareness increase with practice in metacontrast masking
Author(s) -
Caspar M. Schwiedrzik,
Wolf Singer,
Lucía Melloni
Publication year - 2009
Publication title -
journal of vision
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.126
H-Index - 113
ISSN - 1534-7362
DOI - 10.1167/9.10.18
Subject(s) - percept , stimulus onset asynchrony , psychology , perception , stimulus (psychology) , blindsight , cognitive psychology , binocular rivalry , audiology , visual perception , neuroscience , medicine
Can practice effects on unconscious stimuli lead to awareness? Can we "learn to see"? Recent evidence suggests that blindsight patients trained for an extensive period of time can learn to discriminate and consciously perceive stimuli that they were previously unaware of. So far, it is unknown whether these effects generalize to normal observers. Here we investigated practice effects in metacontrast masking. Subjects were trained for five consecutive days on the stimulus onset asynchrony (SOA) that resulted in chance performance. Our results show a linear increase in sensitivity (d') but no change in bias (c) for the trained SOA. This practice effect on sensitivity spreads to all tested SOAs. Additionally, we show that subjects rate their perceptual awareness of the target stimuli differently before and after training, exhibiting not only an increase in sensitivity, but also in the subjective awareness of the percept. Thus, subjects can indeed "learn to see."