Lateralization of movement-related potentials and the size of corpus callosum

Using structural MRI and whole-head EEG recordings, we analyzed the correla tions between the anatomical parameters of the corpus callosum and the hemi spheric distribution of the cortical movement-related potentials during rig ht finger and shoulder movements in nine right-handed men. Statistically si gnificant correlation was found only in finger movements. A relatively larg e genu and the anterior part of the truncus of the corpus callosum correlat ed with enhanced pre-movement EEG potential over the ipsilateral M1/S1 area . The lateralization of the movement-related potentials correlates with the size of those callosal regions which connect the homologous areas of the p rimary sensorimotor and frontal cortices. NeuroReport 11:329-332 (C) 2000 L ippincott Williams & Wilkins.