Relationships between migraine and interoception: normal accuracy but altered sensibility and behaviour

BackgroundMigraine is typically precipitated by unaccustomed changes in ones internal state and/or external environment. Migraine symptoms largely involve increased, noxious, awareness of bodily changes and external stimuli. Links have been proposed between migraine and interoception (sensing and interpreting internal states), but direct evidence is limited. MethodsUnmedicated, otherwise healthy, age-matched female participants were grouped by migraine tendency: control (no unprovoked headaches, n=19); low-frequency (<=3 migraines/month, n=20); high-frequency (>=4 migraines/month, n=19). Interoception was assessed, interictally, with standardised questionnaires such as MAIA-2 and a widely used heartbeat counting task. ResultsThe notable significant questionnaire-based difference was in the noticing, not distracting domain of the MAIA-2; controls were least likely to continue activities despite experiencing physical discomfort, and high-frequency migraineurs most likely. Follow-up questioning clarified that this behaviour related predominantly to migraine-related symptoms. The heartbeat task found no differences in accuracy, but lower confidence in the low-frequency migraine group than the control and high-frequency groups. ConclusionsWe suggest that low interoceptive confidence is a risk factor for migraine, whilst amplification of interoceptive signals caused by migraine restores this confidence, but at the price of migraines disabling symptoms. Self-reported tendency to deliberately ignore physical discomfort, including that caused by migraine, may result in more migraine attacks.