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Full-Text Articles in Medicine and Health Sciences
Dynamics Of Alpha Control: Preparatory Suppression Of Posterior Alpha Oscillations By Frontal Modulators Revealed With Combined Eeg And Event-Related Optical Signal, Kyle E. Mathewson, Diane M. Beck, Tony Ro, Edward L. Maclin, Kathy A. Low, Monica Fabiani, Gabriele Gratton
Dynamics Of Alpha Control: Preparatory Suppression Of Posterior Alpha Oscillations By Frontal Modulators Revealed With Combined Eeg And Event-Related Optical Signal, Kyle E. Mathewson, Diane M. Beck, Tony Ro, Edward L. Maclin, Kathy A. Low, Monica Fabiani, Gabriele Gratton
Publications and Research
We investigated the dynamics of brain processes facilitating conscious experience of external stimuli. Previously, we proposed that alpha (8–12 Hz) oscillations, which fluctuate with both sustained and directed attention, represent a pulsed inhibition of ongoing sensory brain activity. Here we tested the prediction that inhibitory alpha oscillations in visual cortex are modulated by top–down signals from frontoparietal attention networks. We measured modulations in phase-coherent alpha oscillations from superficial frontal, parietal, and occipital cortices using the event-related optical signal (EROS), a measure of neuronal activity affording high spatiotemporal resolution, along with concurrently recorded EEG, while participants performed a visual target detection …
Direct Control Of Visual Perception With Phase-Specific Modulation Of Posterior Parietal Cortex, Andrew Jaegle, Tony Ro
Direct Control Of Visual Perception With Phase-Specific Modulation Of Posterior Parietal Cortex, Andrew Jaegle, Tony Ro
Publications and Research
We examined the causal relationship between the phase of alpha oscillations (9–12 Hz) and conscious visual perception using rhythmic TMS (rTMS) while simultaneously recording EEG activity. rTMS of posterior parietal cortex at an alpha frequency (10 Hz), but not occipital or sham rTMS, both entrained the phase of subsequent alpha oscillatory activity and produced a phase-dependent change on subsequent visual perception, with lower discrimination accuracy for targets presented at one phase of the alpha oscillatory waveform than for targets presented at the opposite phase. By extrinsically manipulating the phase of alpha before stimulus presentation, we provide direct evidence that the …