Electroencephalograms in basilar artery migraine.

Nine cases of 'basilar artery migraine' (BAM) have been recorded. In 8 cases, excess of beta activity was observed during the attacks and disappeared in less than 3 days. The inter-ictal EEGs were normal. Drug ingestion was excluded each time. These EEG patterns are different from those which have been reported in the literature, i.e., transitory posterior abnormal slow waves. However, case no.1 is in agreement with the literature. The expression 'BAM' probably covers different syndromes which are further discussed.