Quantitative EEG recording of a migraine attack

Background and aims Records of EEG during the post ictal period of migraine attack usually show electrical abnormalities of cortical activity mostly related to unspecific symptoms as drowsiness or hyperventilation. However, patients have abnormal EEG rhythms also during the visual aura with an overall slow activity and variation in power spectral values due to a decreased alpha activity in the posterior leads with an increased theta and delta power in the frontocentral regions mimicking some features of true epileptic patients. Methods We address this issue by showing a case of a 15 years old girl that that during an EEG recording, started to complain a visual and sensory aura followed by a severe unilateral pulsating pain. EEG trace was acquired and record was cut it in time blocks of 20 s each one and analyzed, block by block, by employing quantitative EEG (qEEG) technique. In each block spectrum frequencies for all cortical area were isolated and compared with a basal recording obtained from the same patient. Results EEG traces were analyzed considering spectrum frequencies and delta, theta and alpha activities were isolated. QEEG showed an increase of slow rhythms during the aura in the posterior leads and a subsequent immediate recovery of fast rhythms in the pain phase recorded in the same locations. Fast rhythms are equally represented in both phases. Conclusions This kind of EEG pattern seems to suggest further possible physiological connections between mechanism of spreading depression and electrical brain activity and may shed new light on pathophysiology of migraine.