To investigate the spatial heterogeneity of cortical excitability in adolescents with migraine, magnetoencephalography (MEG) recordings at a sampling rate of 6,000 Hz were obtained from 35 adolescents with an acute migraine and 35 age- and sex-matched healthy control participants during an auditory-motor task. Neuromagnetic activation from low- to high-frequency ranges (5-1,000 Hz) was measured at sensor and source levels. The heterogeneity of cortical excitability was quantified within each functional modality (auditory vs motor) and hemispherical lateralization. MEG data showed that high-frequency, not low-frequency neuromagnetic signals, showed heterogeneous cortical activation in migraine subjects compared with control participants (P < .001). The alteration of the heterogeneity of cortical excitability in migraine subjects was independent of age and sex. The degree of the neuromagnetic heterogeneity of cortical activation was significantly correlated with headache frequency (r = .71, P < .005). The alteration of cortical excitability in migraine subjects was spatially heterogeneous and frequency dependent, which previously has not been reported. The finding may be critical for developing spatially targeted therapeutic strategies for normalizing cortical excitability with the purpose of reducing headache attacks.
Perspective: This article presents a new approach to quantitatively measure the spatial heterogeneity of cortical excitability in adolescents with migraine using MEG signals in a frequency range of 5 to 1,000 Hz. The characteristics of the location and degree of cortical excitability may be critical for spatially targeted treatment for migraine.
Keywords: Migraine; cortical excitability; headache; high-frequency oscillations; magnetoencephalography.
Copyright © 2016 American Pain Society. Published by Elsevier Inc. All rights reserved.