The repercussions of unconscious priming on the neural correlates subsequent cognition have been explored previously. However, the neural dynamics during the unconscious processing remains largely uncharted. To assess both the complexity and temporal dynamics of unconscious cognition the present study contrasts the evoked response from classes of masked stimuli with three different levels of complexity; words, consonant strings, and blanks. The evoked response to masked word stimuli differed from both consonant strings and blanks, which did not differ from each other. (...) This response was qualitatively different to any evoked potential observed when stimuli were consciously visible and peaked at 140 ms, earlier than is usually associated with differences between words and strings and 100 ms earlier than word-consonant string differences in the visible condition. The evoked response demonstrates a qualitatively distinct signature of unconscious cognition and directly demonstrates the extraction of abstract information under subliminal conditions. (shrink)

Most consciousness researchers, almost no matter what their views of the metaphysics of consciousness, can agree that the first step in a science of consciousness is the search for the neural correlate of consciousness (the NCC). The reason for this agreement is that the notion of ‘correlation’ doesn’t by itself commit one to any particular metaphysical view about the relation between (neural) matter and consciousness. For example, some might treat the correlates as causally related, while others might view the correlation (...) as evidence for identity between conscious states and brain states. The common ground therefore seems to be that the scientific search for the NCC is largely independent of the metaphysics of consciousness. (shrink)