Besides the hippocampus, early studies making use of intracranial recorded evoked potentials, EEG or MEG demonstrated the involvement of the thalamus, insula and superior temporal gyrus. Some studies combined EEG with fMRI demonstrating that both techniques indicated nearly the same brain areas involved in the P300 component, i.e. the temporoparietal junctions, supplementary motor areas (SMA), anterior cingulate cortex, insula and medial frontal gyrus