Now you feel it—now you don't: ERP correlates of somatosensory awareness
Authors: Schubert, Ruth1; Blankenburg, Felix1; Lemm, Steven; Villringer, Arno1; Curio, Gabriel2
Source: Psychophysiology, Volume 43, Number 1, January 2006 , pp. 31-40(10)
Publisher: Blackwell Publishing
Abstract:
We investigated correlates of somatosensory awareness for supratheshold 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.Keywords: Perceptual awareness; Somatosensory event-related potentials; Masking; Primary somatosensory cortex; Frontoparietal network; Spatial attention
Document Type: Research article
DOI: 10.1111/j.1469-8986.2006.00379.x
Affiliations: 1: Department of Neurology, Charité–University Medicine, Campus Mitte, Berlin, Germany 2: Neurophysics Group, Charité–University Medicine, Campus Benjamin Franklin, Berlin, Germany

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