Zhongming Liu1, Jacco A. de Zwart1, Peter van Gelderen1, Li-Wei Kuo1, Jeff H. Duyn1
1Advanced MRI Section, Laboratory
of Functional & Molecular Imaging, NINDS, National Institutes of Health,
Both evoked and induced neural activities contribute to the observed BOLD signal change in response to stimulus or task. By using simultaneous fMRI-EEG and frequency-tagging techniques, we found within visual cortex positive correlation between BOLD and evoked EEG power change tagged with the stimulus frequency, and negative partial correlation between BOLD and induced alpha power change in extended occipital and parietal cortices. Results suggest that stimulus (or task) yields spatially and temporally specific evoked response, as well as much less specific alteration in baseline spontaneous activity.