EEG was recorded from the left and the right parietal areas in normal subjects with eyes-closed while they were engaged in mental arithmetic, recalls of verbal (Japanese
kanji characters,
kana syllabary, and the alphabet) and visual (scenery) imageries. Fourier analysis of EEG revealed attenuations of the alpha activity (a) in the left hemisphere during the mental arithmetic, (b) in the right hemisphere during the visual imagination of a scenery, and (c) in the both hemispheres during the
kanji imagery accompanied by a stroke-count task. Results suggest that the
kanji characters seem to activate cognitive processes of the both hemispheres. No attenuation of the alpha activity in the both hemispheres was seen during either the alphabet or
kana syllabary imagery.
View full abstract