This article reports four subliminal perception experiments using the relationship between confidence and accuracy to assess awareness. Subjects discriminated among stimuli and indicated their confidence in each discrimination response. Subjects were classified as being aware of the stimuli if their confidence judgments predicted accuracy and as being unaware if they did not. In the first experiment, confidence predicted accuracy even at stimulus durations so brief that subjects claimed to be performing at chance. This finding indicates that subjects's claims that they (...) are ''just guessing'' should not be accepted as sufficient evidence that they are completely unaware of the stimuli. Experiments 2-4 tested directly for subliminal perception by comparing the minimum exposure duration needed for better than chance discrimination performance against the minimum needed for confidence to predict accuracy. The latter durations were slightly but significantly longer, suggesting that under certain circumstances people can make perceptual discriminations even though the information that was used to make those discriminations is not consciously available. (shrink)

Five experiments are reported that concern selective perception and representation following dichotic presentations of competing word pairs differing only in their initial consonants . Only one word from each pair tended to be subjectively perceived, even when participants were encouraged to guess two words. Robust selective perception effects were evidenced as a function of stimulus affective valence. Control tasks showed that these effects could not be attributed to report biases or to the acoustic properties of the stimuli. The unreported words (...) were not recognized on a two-alternative forced-choice task but were recognized with a more sensitive ranking task. Additional cognitive activity during the intertrial interval weakened memory only for the words reported as perceived. Moreover, negative affective valence decreased the recognition of words reported as consciously perceived but increased recognition of unreported words. The implications of these findings for theories of unconscious processing are discussed. (shrink)