MEG and EEG evoked by verbal cognitive tasks

We observed the brain electrical activities associated with verbal cognitive processes by measuring both EEGs and MEGs evoked by visually cognitive tasks. English words, nonsense words and random dots were presented. We discussed the source estimation at latencies of 150 msec and 360 msec using MEG data. At 150 msec, two equivalent current dipoles are localized in or near the primary visual cortex. The dipole sources for recognition of English words at 360 msec were estimated in both hemispheres, and the dipole moment in the left hemisphere was larger than the dipole moment of the right hemisphere. However, we could not find sources common to all subjects.