Systematic prospective records of aura symptoms were obtained from 50 patients, who filled in report forms during the aura phase of two attacks. The pattern of the various aura symptoms was remarkably constant during two attacks. Visual aura was recorded by 94% of the patients, somato-sensory aura symptoms by 40%, motor disturbances by 18% and speech difficulties by 20%. Visual aura was unilateral in 55%, somato-sensory aura symptoms were unilateral in 80% and motor aura was unilateral in 100%. Surprisingly, headache was absent in 20% of the aura attacks. When unilateral headache and unilateral aura symptoms occurred in the same attack, headache was most often contralateral to the somato-sensory and motor aura symptoms. Our observations are in accordance with the hypothesis that the pathophysiological process responsible for the aura symptoms in classic migraine starts at the visual cortex.