title: The Tactile Window to Consciousness is Characterized by Frequency-Specific Integration and Segregation of the Primary Somatosensory Cortex.
abstract: We recently proposed that besides levels of local cortical excitability, also distinct pre-stimulus network states (windows to consciousness) determine whether a near-threshold stimulus will be consciously perceived. In the present magnetoencephalography study, we scrutinised these pre-stimulus network states with a focus on the primary somatosensory cortex. For this purpose participants performed a simple near-threshold tactile detection task. Confirming previous studies, we found reduced alpha and beta power in the somatosensory region contralateral to stimulation prior to correct stimulus detection as compared to undetected stimuli, and stronger event-related responses following successful stimulus detection. As expected, using graph theoretical measures, we also observed modulated pre-stimulus network level integration. Specifically, the right primary somatosensory cortex contralateral to stimulation showed an increased integration in the theta band, and additionally, a decreased integration in the beta band. Overall, these results underline the importance of network states for enabling conscious perception. Moreover, they indicate that also a reduction of irrelevant functional connections contributes to the window to consciousness by tuning pre-stimulus pathways of information flow.
authors: CIMeC, University of Trento, via delle Regole, 101, 38123 Mattarello (TN), Italy.|Center for Cognitive Neuroscience, Paris-Lodron Universität Salzburg, Hellbrunnerstr. 34, 5020 Salzburg, Austria.
authors: Julia Natascha
authors: JN
authors: Frey
authors: CIMeC, University of Trento, via delle Regole, 101, 38123 Mattarello (TN), Italy.|Center for Cognitive Neuroscience, Paris-Lodron Universität Salzburg, Hellbrunnerstr. 34, 5020 Salzburg, Austria.
authors: Philipp
authors: P
authors: Ruhnau
authors: Department of Psychology, University of Konstanz, Universitätsstr. 10, 78464 Konstanz, Germany.
authors: Sabine
authors: S
authors: Leske
authors: Centre for Integrative Neuroscience &MEG Center, University of Tübingen, Otfried-Müller-Str. 47, 72076 Tübingen, Germany.
authors: Markus
authors: M
authors: Siegel
authors: CIMeC, University of Trento, via delle Regole, 101, 38123 Mattarello (TN), Italy.|Centre for Integrative Neuroscience &MEG Center, University of Tübingen, Otfried-Müller-Str. 47, 72076 Tübingen, Germany.
authors: Christoph
authors: C
authors: Braun
authors: CIMeC, University of Trento, via delle Regole, 101, 38123 Mattarello (TN), Italy.|Center for Cognitive Neuroscience, Paris-Lodron Universität Salzburg, Hellbrunnerstr. 34, 5020 Salzburg, Austria.
authors: Nathan
authors: N
authors: Weisz
mesh_terms: D000328:Adult; D001931:Brain Mapping; D003243:Consciousness / Q000502:physiology*; D005073:Evoked Potentials, Somatosensory / Q000502:physiology*; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D015225:Magnetoencephalography; D008297:Male; D009415:Nerve Net / Q000502:physiology; D010812:Physical Stimulation; D011930:Reaction Time; D013003:Somatosensory Cortex / Q000033:anatomy & histology / Q000502:physiology*; D014110:Touch / Q000502:physiology*; D055698:Touch Perception / Q000502:physiology*