The transcranial Doppler (TCD) and cardiovascular responses to established tests of autonomic function were studied in 50 migraineurs (23 of whom experienced aura and 27 who did not) and 30 healthy control subjects. In addition to the measurements outside attacks, 10 migraineurs were also tested during unilateral attacks of migraine without aura. Transcranial Doppler examinations of middle cerebral artery (MCA) blood velocity showed no differences between migraineurs and healthy subjects and no difference between migraineurs experiencing an attack and outside an attack when examined in response to a head-up tilt test, a cold-pressor test and a Valsalva manoeuvre. The cardiovascular reflexes in response to the Valsalva manoeuvre suggested a mild parasympathetic hypofunction in migraineurs, both those with and those without aura. On the basis of the present results and previous findings by others, we conclude that mild parasympathetic hypofunctioning with preserved sympathetic functioning is an established finding in migraine both with and without aura.