title: Occipital MEG Activity in the Early Time Range (<300 ms) Predicts Graded Changes in Perceptual Consciousness.
abstract: Two electrophysiological components have been extensively investigated as candidate neural correlates of perceptual consciousness: An early, occipitally realized component occurring 130-320 ms after stimulus onset and a late, frontally realized component occurring 320-510 ms after stimulus onset. Recent studies have suggested that the late component may not be uniquely related to perceptual consciousness, but also to sensory expectations, task associations, and selective attention. We conducted a magnetoencephalographic study; using multivariate analysis, we compared classification accuracies when decoding perceptual consciousness from the 2 components using sources from occipital and frontal lobes. We found that occipital sources during the early time range were significantly more accurate in decoding perceptual consciousness than frontal sources during both the early and late time ranges. These results are the first of its kind where the predictive values of the 2 components are quantitatively compared, and they provide further evidence for the primary importance of occipital sources in realizing perceptual consciousness. The results have important consequences for current theories of perceptual consciousness, especially theories emphasizing the role of frontal sources.
authors.affiliation: Cognitive Neuroscience Research Unit (CNRU), Center of Functionally Integrative Neuroscience (CFIN), Aarhus University, Aarhus, Denmark.
authors.forename: Lau M
authors.initials: LM
authors.lastname: Andersen
authors.affiliation: Cognitive Neuroscience Research Unit (CNRU), Center of Functionally Integrative Neuroscience (CFIN), Aarhus University, Aarhus, Denmark.
authors.forename: Michael N
authors.initials: MN
authors.lastname: Pedersen
authors.affiliation: Cognitive Neuroscience Research Unit (CNRU), Center of Functionally Integrative Neuroscience (CFIN), Aarhus University, Aarhus, Denmark Hammel Neurorehabilitation and Research Center, Institute of Clinical Medicine, Aarhus University, Hammel, Denmark UCL Institute of Cognitive Neuroscience, University College London, London, UK.
authors.forename: Kristian
authors.initials: K
authors.lastname: Sandberg
authors.affiliation: Cognitive Neuroscience Research Unit (CNRU), Center of Functionally Integrative Neuroscience (CFIN), Aarhus University, Aarhus, Denmark Center for Cognitive Neuroscience, Department of Communication and Psychology, Aalborg University, Aalborg, Denmark.
authors.forename: Morten
authors.initials: M
authors.lastname: Overgaard
mesh_terms: D000328:Adult; D001921:Brain / Q000502:physiology*; D003243:Consciousness / Q000502:physiology*; D006801:Humans; D015225:Magnetoencephalography / Q000379:methods; D008297:Male; D015999:Multivariate Analysis; D010775:Photic Stimulation; D012815:Signal Processing, Computer-Assisted; D013997:Time Factors; D014796:Visual Perception / Q000502:physiology*; D055815:Young Adult
keywords: classification; consciousness; magnetoencephalography; neural correlate of consciousness; perception