Low interhemispheric and high intrahemispheric EEG coherence in migraine

Twenty women with migraine were evaluated by EEG coherence analysis. In com parison with controls, the migrainous subjects showed lower interhemispheri c coherence values at C3-C4 for the delta band (P=0.0030) and at F3-F4 (P=0 .0055) and C3-C4 (P=0.0018) for the beta band frequency (Wilcoxon criterion ). In contrast, 22 intrahemispheric coherence pairs were significantly high er in the migraine group than in the control group (P<0.01), The subjects w ith visual aura showed lower interhemispheric coherence at O1-O2 and T5-T6 for the alpha band than the subjects without the aura. Discriminant analysi s revealed that 95% of the subjects with migraine and 85% of the controls w ere correctly classified into their proper groups. We suggest that EEG cohe rence analysis is a sensitive parameter in the detection of electrophysiolo gical abnormalities in patients with migraine.