Multimodal Functional Neuroimaging: Integration of fMRI and EEG/MEG data
The electroencaphalogram (EEG) and the functional magnetic resonance imaging (fMRI) constitute the prevailing tools to study the brain functioning in both healthy individuals and patients with a variety of neurological disorders. For about two decades, physicists and biomedical engineers have struggled to determine the biophysical mechanisms underlying these two neuroim-aging modalities. Recent efforts by different groups have been on: a) developing forward-generative models as well as strategies for their statistical inference, b) performing EEG-fMRI concurrent recording and data fusion, and c) establishing suitable animal models for specific brain dysfunctions. Here, I first review preliminary studies in humans where interesting problems related to these emergent research/technological lines are presented. Then, I discuss recent achievements by members of my group in Tohoku University, Sendai Japan, using animal models to examine how neuronal activity is translated into EEG and fMRI signals, and in which situations we must expect alterations in these signals, e.g. in the case of Alzheimer disease.