Electrophysiological neuroimaging: cortical correlates of alpha rhythm modulation

Eyes-open and eyes-closed are two widely accepted resting conditions in neuroimaging study. When alternating between the two conditions, electroencephalogram (EEG) studies have reported the modulation of alpha band (8-12 Hz) oscillation. Functional magnetic resonance imaging (fMRI) studies have found modulation of blood-oxygen-level dependent (BOLD) response. The neuronal correlates of the two modulations are not well understood. In the present study, we conducted an eyes-open-eyes-closed human experiment with simultaneous EEG and fMRI recordings. We investigated the spatial and temporal correlations between the alpha modulation and BOLD response. Besides the neural network generating the eyes-open-eyes-closed-task-induced modulation, we further examined other neural networks involved in the task. Their spatial and temporal relationship with the alpha modulation was investigated.