Right Parietal Brain Activity Precedes Perceptual Alternation of Bistable Stimuli.

@article{citeulike:2723863, abstract = {Momentary fluctuations of baseline activity have been shown to influence responses to sensory stimulation both behaviorally and neurophysiologically. This suggests that perceptual awareness does not solely arise from physical stimulus properties. Here we studied whether the momentary state of the brain immediately before stimulus presentation indicates how a physically unique but perceptually ambiguous stimulus will be perceived. A complex Necker cube was intermittently presented and subjects indicated whether their perception changed with respect to the preceding presentation. EEG was recorded from 256 channels. The prestimulus brain-state was defined as the spatial configuration of the scalp potential map within the 50 ms before stimulus arrival, representing the sum of all momentary ongoing brain processes. Two maps were found that doubly dissociated perceptual reversals from perceptual stability. For EEG sweeps classified as either map, distributed inverse solutions were computed and statistically compared. This yielded activity confined to a region in right inferior parietal cortex that was significantly more active before a perceptual reversal. In contrast, no significant topographic differences of the evoked potentials elicited by stable vs. reversed Necker cubes were found. This indicates that prestimulus activity in right inferior parietal cortex is associated with the perceptual change.}, address = {Department of Fundamental Neuroscience.}, author = {Britz, Juliane and Landis, Theodor and Michel, Christoph M M. }, citeulike-article-id = {2723863}, issn = {1460-2199}, journal = {Cerebral cortex (New York, N.Y. : 1991)}, keywords = {baseline, kristina, neuromodulation}, month = {April}, posted-at = {2008-04-27 14:03:44}, priority = {2}, title = {Right Parietal Brain Activity Precedes Perceptual Alternation of Bistable Stimuli.}, url = {http://view.ncbi.nlm.nih.gov/pubmed/18424780}, year = {2008} }

TY - JOUR ID - citeulike:2723863 L3 - citeulike-article-id:2723863 TI - Right Parietal Brain Activity Precedes Perceptual Alternation of Bistable Stimuli. JF - Cerebral cortex (New York, N.Y. : 1991) AD - Department of Fundamental Neuroscience. SN - 1460-2199 N2 - Momentary fluctuations of baseline activity have been shown to influence responses to sensory stimulation both behaviorally and neurophysiologically. This suggests that perceptual awareness does not solely arise from physical stimulus properties. Here we studied whether the momentary state of the brain immediately before stimulus presentation indicates how a physically unique but perceptually ambiguous stimulus will be perceived. A complex Necker cube was intermittently presented and subjects indicated whether their perception changed with respect to the preceding presentation. EEG was recorded from 256 channels. The prestimulus brain-state was defined as the spatial configuration of the scalp potential map within the 50 ms before stimulus arrival, representing the sum of all momentary ongoing brain processes. Two maps were found that doubly dissociated perceptual reversals from perceptual stability. For EEG sweeps classified as either map, distributed inverse solutions were computed and statistically compared. This yielded activity confined to a region in right inferior parietal cortex that was significantly more active before a perceptual reversal. In contrast, no significant topographic differences of the evoked potentials elicited by stable vs. reversed Necker cubes were found. This indicates that prestimulus activity in right inferior parietal cortex is associated with the perceptual change. KW - baseline KW - kristina KW - neuromodulation AU - Britz, Juliane AU - Landis, Theodor AU - Michel, Christoph M PY - 2008/04/18/ UR - http://view.ncbi.nlm.nih.gov/pubmed/18424780 ER -