Progress and challenges in multimodal data fusion

Independently, different brain imaging methods provide compromised spatial and temporal resolutions. Anatomical MRI provides highly accurate information about the individual cortical anatomy. In functional imaging, fMRI is temporally limited by the slow time course of the hemodynamic response, but can provide spatial sampling on a millimeter scale. EEG and MEG in turn provide a temporal resolution of milliseconds, but the localization of sources is more complicated because of the electromagnetic inverse problem. Combining information provided by both anatomical and functional MRI with EEG/MEG data thus facilitates the elucidation of the spatial distribution and temporal orchestration of human brain activity.