How a Migraine Happens
Theories about migraine pain
Older theories about migraines suggested that symptoms were possibly due to changes
in blood flow to the brain. Now many headache researchers realize that changes in
blood flow and blood vessels don't start the pain but may add to it.
Current thinking regarding migraine pain has moved more toward the source of the problem,
as improved technology and research have paved the way for a better understanding.
Today it is widely understood that chemical compounds and hormones, such as serotonin
and estrogen, often play a role in pain sensitivity for migraine sufferers. More recently,
proteins made by nerve cells (neuropeptides) have been shown to be involved in the
pathway that leads to a migraine.
One aspect of migraine pain theory explains that migraine pain happens due to waves
of activity by groups of excitable brain cells. These trigger chemicals, such as serotonin,
to narrow blood vessels. Serotonin is a chemical that's needed for nerve cells to
communicate. It can cause narrowing of blood vessels all over the body.
When serotonin or estrogen levels change, the result for some is a migraine. Serotonin
levels may affect both men and women. Changing estrogen levels affect women only.
For women, estrogen levels naturally vary over their lifetime. There are increases
during the childbearing years and decreases afterwards. Women of childbearing age
also have monthly changes in estrogen levels. Migraines in women are often linked
to these fluctuating hormone levels. They may explain why women are more likely to
have migraines than men.
Some research suggests that when estrogen levels rise and then fall, contractions
in blood vessels may be set off. This leads to throbbing pain. Other data suggest
that lower estrogen levels make facial and scalp nerves more sensitive to pain. Experts
are still studying exactly how neuropeptides, serotonin, and hormones interact to
What commonly triggers a migraine?
People who get migraines may be able to identify triggers that seem to kick off the
symptoms. Some possible triggers include:
Stress and other emotions
Biological and environmental conditions, such as hormonal shifts or exposure to light
Severe tiredness (fatigue) and changes in sleep patterns
Glaring or flickering lights
Certain foods and drinks
The American Headache Society suggests writing down your triggers in a headache diary. Take
this information with you when you visit your healthcare provider helps them to find
headache management strategies.