Table 1 Synoptic table of neurophysiological changes comparing episodic migraine with aura (MA) between attacks, during the aura phase, and familiar hemiplegic migraine (FHM). Arrows indicate the direction of change

 EEG & MEG

↑ photic driving, ↑ of slow, and hyper synchronized alpha rhythmic activity

On EEG, mild asymmetry of slow waves contralateral to the visual fiend defect

Unilateral or bilateral delta EEG activity – sometimes spreading postero-anteriorly – and ↓ of alpha

On MEG, alpha and gamma rhythm ERD contralateral to the visual fiend defect, slow direct current potential shifts

 EP & ERP grand-average

↑ amplitude (more than in MO) or normal, ↓ thalamocortical activity

↓ or abolition of cortical EPs in the hemisphere contralateral to the field defect

 EP & ERP Habituation

↓ habituation (more than in MO) or normal

↓ habituation during persistent aura without infarction

Significantly more pronounced habituation during VEPs and nBR recordings than controls

 TMS

Paradoxical effects to enhancing and reducing paradigms of stimulation

↓ MEP amplitude on the ictally paretic side

 EMG recordings

↓ Habituation of nBR, subclinical abnormalities of neuromuscular transmission on SFEMG