Altered cortical activation in adolescents with acute migraine: a magnetoencephalography study

Abstract

To quantitatively assess cortical dysfunction in pediatric migraine, 31 adolescents with acute migraine and age- and gender-matched controls were studied using a magnetoencephalography (MEG) system at a sampling rate of 6,000 Hz. Neuromagnetic brain activation was elicited by a finger-tapping task. The spectral and spatial signatures of magnetoencephalography data in 5 to 2,884 Hz were analyzed using Morlet wavelet and beamformers. Compared with controls, 31 migraine subjects during their headache attack phases (ictal) showed significantly prolonged latencies of neuromagnetic activation in 5 to 30 Hz, increased spectral power in 100 to 200 Hz, and a higher likelihood of neuromagnetic activation in the supplementary motor area, the occipital and ipsilateral sensorimotor cortices, in 2,200 to 2,800 Hz. Of the 31 migraine subjects, 16 migraine subjects during their headache-free phases (interictal) showed that there were no significant differences between interictal and control MEG data except that interictal spectral power in 100 to 200 Hz was significantly decreased. The results demonstrated that migraine subjects had significantly aberrant ictal brain activation, which can normalize interictally. The spread of abnormal ictal brain activation in both low- and high-frequency ranges triggered by movements may play a key role in the cascade of migraine attacks.

Perspective: This is the first study focusing on the spectral and spatial signatures of cortical dysfunction in adolescents with migraine using MEG signals in a frequency range of 5 to 2,884 Hz. This methodology analyzing aberrant brain activation may be important for developing new therapeutic interventions for migraine in the future.

Keywords: Migraine; high-frequency oscillations; magnetoencephalography (MEG); pediatric; wavelet.

Figure 1

Polarity spectrograms and contour maps of MEG data in 5 to 100 Hz recorded from a migraine subject and a control during finger movements. The polarity spectrograms (upper row) show the spectral components in 5 to 30 Hz, which are indicated by numerals 1, 2, and 3. The migraine subject has activation outside of the primary motor cortex (white arrows). The green asterisk (*) in the contour maps indicates the position of the corresponding spectrogram that is shown above the contour maps.

Figure 2

Polarity spectrograms and contour maps of MEG data in 100 to 1,000 Hz recorded from a migraine subject and a control duringfinger movements. The polarity spectrograms (upper row) show the focal increaseof spectral power indicatedby black arrows. The migraine subject has activation outside of the primary motor cortex (white arrows). The green asterisk (*) in the contour maps indicates the position of the corresponding spectrogram that is shown above the contour map.

Figure 3

Polarity spectrograms and contour maps of MEG data in 1,000 to 2,884 Hz recorded from a migraine subject and a control during finger movements. The polarity spectrograms (upper row) show the focal increase of spectral power in a very-high-frequency range (~2,640 Hz). The migraine subject has activation outside of the primary motor cortex (white arrows). The green asterisk (*) in the contour maps indicates the position of the corresponding spectrogram that is shown above the contour map.

Figure 4

The latencies of the first and second spectral components in 5 to 30 Hz in migraine subjects and controls. Abbreviations: 1 LFM, the first component elicited by left finger movements; 2 LFM, the second component elicited by left finger movements; 1 RFM, the first component elicited by right finger movements; 2 RFM, the second component elicited by right finger movements; SE, standard error. *P < .01; **P < .001.

Figure 5

Magnetic source imaging showing the locations of finger movement-elicited neuromagnetic activation in 5 to 30 Hz, 100 to 200 Hz, and 2,200to2,800Hzin amigraine subject (Migraine) and acontrol (Control). The primary motor cortexinthe contralateral hemisphere isactivatedin both the migraine subject and the control. The supplementary motor area, the ipsilateral sensorimotor cortex, and the occipital cortex are activated only in the migraine subject (green arrows). Abbreviations: R, right; L, left.