Why do we get migraines?
Research: Leah Hinners
Traditional Artist: Peter Stavros
Digital Artist: Isra Ahmed
More Than Headaches
Migraines are intense throbbing pains. They are generally unilateral, meaning they occur on one side of the head. They are recurring, and can last anywhere from a few hours to 3 days (NINDS).
Migraines often cause nausea and vomiting. Certain migraines can cause blurry vision, and migraineurs (people with migraines) often see a “migraine aura,” or blurry spots that obstruct their vision (NINDS).
The true cause of migraines is unknown, but they can be exacerbated by intense stress and emotions. For women, changes in estrogen levels can cause migraines, and is the reason women are 3x more likely to get migraines than men (Hopkins). The onset of a migraine can be triggered by a lack of sleep, stress weather, flashing lights (Hopkins).
Physical Changes with Migraines
Migraine pain signals are sent by the trigeminovascular system, which is a subcortical complex that supplies the nerves for sensory perception. Like all subcortical structures, the trigeminovascular system is deep behind the outer cortex of the brain. In MRIs, white matter abnormalities (WMA) can be seen in subcortical structures. These WMAs are clusters of myelin that appear white on MRIs. The relationship between WMAs and migraines is unknown, but migraines are 2-4x more likely to have WMA.
Migraine Diagnostic Criteria
There are 3 types of migraines: migraines with aura, migraines without aura, and chronic (NEJM). In order for a migraine without aura to be diagnosed, 5 or more attacks with at least 2 of the following symptoms need to have happened:
a. Unilateral pain location
b. Pulsating, throbbing
c. Pain interferes with daily physical activity
d. Photophobia (light sensitivity)
e. Phonophobia (sound sensitivity)
The cause of migraines is largely unknown, so treatments are speculative. Two molecules transmitted by the trigeminovascular system thought to be involved in the sensation of migraine pain are Calcitonin Gene-Related Peptide (CGRP) and Nitric Oxide. Some treatment drugs prevent the reception of CGRP signals and the production of Nitric Oxide to disrupt the migraine signal pathway. However, the true relationship between these neurotransmitters and migraines is still unknown, and so the effectiveness of these medications has been questioned.