Fig. 1From: Brain-derived neurotrophic factor in primary headachesa Significant increase of brain-derived neurotrophic factor (BDNF) during migraine attacks (ATT) compared with headache-free periods (INT), tension-type headache (TTH), and healthy controls (HC). b Comparison of BDNF levels in 19 patients, for whom paired samples—during migraine attacks (ATT) and headache-free periods (INT)—were availableBack to article page