To See or Not to See: Prestimulus alpha Phase Predicts Visual Awareness Export

@article{citeulike:4169485, abstract = {We often fail to see something that at other times is readily detectable. Because the visual stimulus itself is unchanged, this variability in conscious awareness is likely related to changes in the brain. Here we show that the phase of EEG {alpha} rhythm measured over posterior brain regions can reliably predict both subsequent visual detection and stimulus-elicited cortical activation levels in a metacontrast masking paradigm. When a visual target presentation coincides with the trough of an {alpha} wave, cortical activation is suppressed as early as 100 ms after stimulus onset, and observers are less likely to detect the target. Thus, during one {alpha} cycle lasting 100 ms, the human brain goes through a rapid oscillation in excitability, which directly influences the probability that an environmental stimulus will reach conscious awareness. Moreover, ERPs to the appearance of a fixation cross before the target predict its detection, further suggesting that cortical excitability level may mediate target detection. A novel theory of cortical inhibition is proposed in which increased {alpha} power represents a "pulsed inhibition" of cortical activity that affects visual awareness. 10.1523/JNEUROSCI.3963-08.2009}, author = {Mathewson, Kyle E. and Gratton, Gabriele and Fabiani, Monica and Beck, Diane M. and Ro, Tony}, citeulike-article-id = {4169485}, citeulike-linkout-0 = {http://dx.doi.org/10.1523/JNEUROSCI.3963-08.2009}, citeulike-linkout-1 = {http://www.jneurosci.org/cgi/content/abstract/29/9/2725}, citeulike-linkout-2 = {http://view.ncbi.nlm.nih.gov/pubmed/19261866}, citeulike-linkout-3 = {http://www.hubmed.org/display.cgi?uids=19261866}, day = {4}, doi = {10.1523/JNEUROSCI.3963-08.2009}, journal = {J. Neurosci.}, keywords = {alpha, eeg, human, oscillation, vision}, month = {March}, number = {9}, pages = {2725--2732}, posted-at = {2009-03-17 05:47:28}, priority = {2}, title = {To See or Not to See: Prestimulus {alpha} Phase Predicts Visual Awareness}, url = {http://dx.doi.org/10.1523/JNEUROSCI.3963-08.2009}, volume = {29}, year = {2009} }

TY - JOUR ID - citeulike:4169485 L3 - citeulike-article-id:4169485 N2 - We often fail to see something that at other times is readily detectable. Because the visual stimulus itself is unchanged, this variability in conscious awareness is likely related to changes in the brain. Here we show that the phase of EEG {alpha} rhythm measured over posterior brain regions can reliably predict both subsequent visual detection and stimulus-elicited cortical activation levels in a metacontrast masking paradigm. When a visual target presentation coincides with the trough of an {alpha} wave, cortical activation is suppressed as early as 100 ms after stimulus onset, and observers are less likely to detect the target. Thus, during one {alpha} cycle lasting 100 ms, the human brain goes through a rapid oscillation in excitability, which directly influences the probability that an environmental stimulus will reach conscious awareness. Moreover, ERPs to the appearance of a fixation cross before the target predict its detection, further suggesting that cortical excitability level may mediate target detection. A novel theory of cortical inhibition is proposed in which increased {alpha} power represents a "pulsed inhibition" of cortical activity that affects visual awareness. 10.1523/JNEUROSCI.3963-08.2009 IS - 9 JF - J. Neurosci. EP - 2732 TI - To See or Not to See: Prestimulus {alpha} Phase Predicts Visual Awareness VL - 29 SP - 2725 KW - alpha KW - eeg KW - human KW - oscillation KW - vision AU - Mathewson, Kyle AU - Gratton, Gabriele AU - Fabiani, Monica AU - Beck, Diane AU - Ro, Tony PY - 2009/03/04/ UR - http://dx.doi.org/10.1523/JNEUROSCI.3963-08.2009 ER -