title: Now you feel it--now you don't: ERP correlates of somatosensory awareness.
abstract: We investigated correlates of somatosensory awareness for supra theshold stimuli using event-related potentials in a masking paradigm: Conscious perception of a weak, but suprathreshold "target" stimulus was suppressed in a significant number of trials when followed by a higher-intensity "mask" stimulus. ERPs were compared for trials with perceived versus unperceived target stimuli. Early ERPs (P60, N80), generated in the contralateral S1, were found independent of stimulus perception. In contrast, for consciously perceived target stimuli, amplitude enhancements were observed for the P100 and N140. Thus, early activation of S1 is not sufficient to warrant conscious stimulus perception. Conscious stimulus processing differs significantly from unconscious processing starting around 100 ms after stimulus presentation when the signal is processed in parietal and frontal cortices, brain regions crucial for stimulus access into conscious perception.
authors.affiliation: Department of Neurology, Charité-University Medicine, Campus Mitte, Berlin, Germany. ruth.schubert@charite.de
authors.forename: Ruth
authors.initials: R
authors.lastname: Schubert
authors.forename: Felix
authors.initials: F
authors.lastname: Blankenburg
authors.forename: Steven
authors.initials: S
authors.lastname: Lemm
authors.forename: Arno
authors.initials: A
authors.lastname: Villringer
authors.forename: Gabriel
authors.initials: G
authors.lastname: Curio
mesh_terms: D000328:Adult; D001364:Awareness / Q000502:physiology*; D003627:Data Interpretation, Statistical; D004558:Electric Stimulation; D004569:Electroencephalography; D005071:Evoked Potentials / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D012677:Sensation / Q000502:physiology*; D012684:Sensory Thresholds / Q000502:physiology