RT Journal Article SR Electronic T1 The neural correlates of consciousness in sleep: A no-task, within-state paradigm JF bioRxiv FD Cold Spring Harbor Laboratory SP 012443 DO 10.1101/012443 A1 Francesca Siclari A1 Joshua J. LaRocque A1 Giulio Bernardi A1 Bradley R. Postle A1 Giulio Tononi YR 2014 UL http://biorxiv.org/content/early/2014/12/30/012443.abstract AB What are the neural correlates of consciousness? Studies that have addressed this question in the past either compared neural activity during tasks in which subjects report perceiving a stimulus or not, or have contrasted conscious wakefulness with unconscious sleep or anesthesia. However, such contrasts may include correlates of stimulus processing, response preparation or of changes in behavioral state, rather than of consciousness per se. To overcome these limitations, we developed a no-task, within-state paradigm in which sleeping subjects recorded with high density-EEG reported retrospectively whether they had been conscious or not. We identified specific frontal and parieto-occipital regions showing EEG changes several seconds preceding awakenings that distinguished between reports of consciousness and unconsciousness. While decreased parieto-occipital low-frequency activity was associated with highly perceptual experiences, increased frontal high-frequency activity was associated with highly thought-like experiences. Finally, we identified localized, content-specific activations for faces, spatial setting, movement and speech experienced in dreams.