To determine whether motion sickness induced by optokinetic stimulation would trigger migraine-like attacks, 27 migraine sufferers and 23 controls attended the laboratory up to three times at intervals of at least 3 weeks. On one occasion subjects experienced up to 15 min of optokinetic stimulation, followed by three 30-s applications of ice to the temple at 4-min intervals. On another occasion, the ice applications preceded and accompanied optokinetic stimulation. On a third occasion, one hand was immersed in ice water for 30 s, three times at 4-min intervals before and during optokinetic stimulation. Subjects recorded headache activity in a diary over the course of the study. None of the controls experienced a migraine-like attack at any stage of the experiment. In migraine sufferers, the incidence of migraine-like attacks was greater than the expected daily incidence of 8% after sessions that involved painful stimulation of the temple during or after optokinetic stimulation (44% and 28% of the group, respectively) ( P < 0.001). In contrast, migraine-like attacks developed in only 13% of migraine sufferers after the session that involved immersing the hand in ice water during optokinetic stimulation (not significant). The development of nausea and headache during optokinetic stimulation increased the likelihood of migraine-like attacks afterwards. These findings indicate that motion sickness and head pain increase susceptibility to migrainous attacks in migraine sufferers, and suggest that the symptoms of migraine build upon each other in a vicious circle. Thus, targeting multiple symptoms should be more effective than targeting individual symptoms, both for preventing and treating attacks of migraine.
Pain expectation and avoidance in the social context: an electrophysiological study
