Fig. 1From: Neurophysiological correlates of clinical improvement after greater occipital nerve (GON) block in chronic migraine: relevance for chronic migraine pathophysiologyStudy design. Patients were recruited at T0. After 1Â month of clinical evaluation, we performed neurophysiological recordings (habituation and IDAP) prior to GON anaesthetic block. Early neurophysiological changes were collected after a week and clinical revaluation was planned at 30Â daysBack to article page