Are migraineurs hypersensitive? A test of the stimulus processing disorder hypothesis

The concept of hypersensitivity in migraineurs was advanced mainly on the basis of studies on information processing in which increased amplitudes and reduced habituation in cortical evoked and event related potentials were found in migraine sufferers. The present investigation examined whether migraineurs exhibit hypersensitivity within three different experimental paradigms and various non electrocortical response parameters. Samples of 24 migraine, 19 tension-type headache sufferers, and 24 normal controls were compared regarding their subjective estimation of intensity and discomfort due to visual and acoustical stimuli. Subjects also participated in an experiment using the eyeblink startle response paradigm. In a last experimental task the Stroop test was applied. The trait variables emotionality, arousal, and extraversion were also measured. None of the experimental tasks revealed the predicted hypersensitivity of migraineurs in relation to the control samples. The series of experiments was conducted a second time with half of the participants in order to replicate the findings. The conclusions remained the same. The results of earlier studies on cortical processing can not be interpreted as demonstrating general hypersensitivity in the sense of a dispositional trait in migraine afflicted individuals irrespective of the involved response system.