How does heredity make me prone to migraines?

Inheriting a tendency for migraine means that your brain and nervous system are more prone to respond to exposure to certain headache triggers by getting a migraine; in other words, you have an increased vulnerability or susceptibility to migraine. This is where the concepts of susceptibility and threshold come in. People who are more susceptible to developing migraines will develop them in response to very low levels of a stimulus, whereas people who are not migraine-prone will not respond to the same level of stimulus. The term threshold refers to the level at which a stimulus will produce a reaction in specific individuals.

Migraine sufferers similarly inherit a lowered threshold or increased susceptibility to migraine. That means exposure to fewer triggers will bring on a headache in a susceptible person, compared to the non-headache prone person. A headache may occur in even non-headache prone individuals if they stay up too late at night, skip breakfast, have a very stressful day, and drink some red wine. For the headache-prone individual, exposure to just one of these potential triggers may result in a headache.