The study aims to help characterize the sort of structures about which people can acquire unconscious knowledge. It is already well established that people can implicitly learn n-grams and also repetition patterns. We explore the acquisition of unconscious structural knowledge of symmetry. Chinese Tang poetry uses a specific sort of mirror symmetry, an inversion rule with respect to the tones of characters in successive lines of verse. We show, using artificial poetry to control both n-gram structure and repetition patterns, that (...) people can implicitly learn to discriminate inversions from non-inversions, presenting a challenge to existing models of implicit learning. (shrink)

In this event-related potential study a masking technique that prevents conscious perception of words and non-words through attentional distraction was used to reveal the temporal dynamics of word processing under non-conscious and conscious conditions. In the non-conscious condition, ERP responses differed between masked words and non-words from 112 to 160 ms after stimulus-onset over posterior brain areas. The early onset of the word–non-word differences was compatible with previous studies that reported non-conscious access to orthographic information within this time period. Moreover, (...) source localisations provided evidence for automatic activation of prelexical phonological information, whereas no evidence for non-conscious semantic processing was found. When subjects were informed about the masking technique, lexical differences occurred at later time intervals, suggesting conscious access to additional word related information. These results indicate that early visual word processing does not depend entirely on attentional resources, but that non-conscious processing probably is restricted to rather lower-level linguistic information. (shrink)

Sandberg et al. show that the Perceptual Awareness Scale scale is sensitive compared to confidence ratings and wagering in detecting accurate perception. They go on to argue that the PAS scale is hence a sensitive measure of conscious perception compared to confidence ratings, a claim disputed here. The fact that some visual content is conscious does not entail that the visual content relevant to making a discrimination is conscious. For example, if one saw a square but was only aware of (...) seeing a flash of something, then one has not consciously seen a square. When PAS and confidence ratings come in conflict, we suggest that it is confidence ratings that more reliably indicate the conscious status of contents allowing discrimination. (shrink)

Comparisons of indirect measures with direct measures can help elucidate the relationship between nonconscious and conscious perception. We report three experiments on masked word priming in which we observed a negative correlation between prime discriminability and priming , i.e. where priming decreased with increasing prime visibility. While such observations are rare , they may indicate a conflict between conscious and nonconscious processing when primes are shown close to the subjective visibility threshold for the priming-relevant information. For instance, such a conflict (...) could occur between nonconscious processing of a prime’s meaning and conscious perception of prime letters. Theoretical accounts that discuss similar conflicts assume that the conflict is resolved either by automatically prioritising conscious processes or by discounting the estimated confusion caused by a prime-target pair . In both cases, priming is predicted to decrease when prime visibility increases from below threshold to perithreshold levels. Therefore, we suggest that negative priming-d’ relationships are most likely observed when the d’ measure assesses prime visibility at a level of representation that is below the level of representation at which priming arises, in terms of a putative hierarchy of word processing. (shrink)