Video assessment of yawning induced by sublingual apomorphine in migraine.

A double-blind, placebo-controlled study was carried out in 14 migraineous outpatients and 8 control subjects to assess yawning response to 0.25 mg of sublingual apomorphine, a dopamine receptor agonist, by means of an audiovisual technique. Apomorphine induced a significantly higher number of yawns than placebo in both groups of subjects, but the effect was significantly greater in migraine sufferers than in controls. The result seems to confirm the previous reported hyper-responsiveness to pharmacological dopaminergic stimulation in migraine sufferers. Moreover, the audiovisual technique seems to be an appropriate tool to study yawning response in man.