The three responses of the blink reflex in adult and juvenile migraine

Recent theories about migraine pathogenesis have emphasized the role of the trigeminal system in the pathogenesis of migraine attacks (Moskowitz, 1997). The blink reflex (BR) could be a suitable method to evaluate the trigeminal system in migraine, as it is generally elicited by stimulation of the trigeminal ophthalmic division (Kimura et al., 1967), involved in migraine attacks. Sixty one adult and 15 juvenile migraine without aura subjects were selected, in order to evaluate the BR features, including the subjective perceptive and pain thresholds and the R1, R2 and R3 components intensity thresholds and amplitudes. The electrophysiological procedure was carried out during the pain free phase. The findings were compared with those of 28 healthy controls, 18 adults and 10 children. In both adult and juvenile migraine sufferers an early appearance of the R3 response at almost the R2 threshold was observed in comparison with age-matched controls. Unfortunately, the anatomic and physiologic organization of the R3 component is uncertain: its early onset could suggest a dysfunction of the inhibitory control system on the trigeminal networks, which may predispose to migraine attacks.