Think about the last time you heard someone complaining about a migraine. Chances are two-to-one that person was a woman -- and not because we ladies are whiners. A new study published this month in the journal Brain reports differences in the brains of male and female migraine sufferers.
The group of Harvard Medical School researchers looked at 44 men and women, half of which suffered migraines, ScienceNow reports. Here's what they found:
- Women and men raed their migraines as equally intense, but the women found them more unpleasant
- MRI's of female migraine sufferers' brains showed thicker gray matter (the brain's connective tissue) in their posterior insula (involved in pain processing) and their precuneus (the area thought to house our sense of self) than both male migraine sufferers and migraine-free subjects
To figure out what this gray matter-thickening meant, the researchers tested the subjects' response to pain -- 15 seconds of heat applied to the hand. These thicker areas in the brains of female migraine sufferers appear to talk to each other and cooperate in the pain response. The mens' brains didn't show this pattern of coordination.
When Maleki checked for sex differences in well-defined pain networks, most of the structures that responded stronger in women were part of the emotional network. "In men, the pain comes in, and the brain says 'ouch,' " Maleki says. "In women, the brain says 'OUCHHHHH!' " Overall, the results suggest that "it's not just one area that underlies the sex differences in migraines, but a network of areas, a system that leads to the problem or progression," she says.
In an interesting twist, the male migraine sufferers' brains showed a stronger response to the painful heat in their nucleus accumbens, part of the reward circuitry largely studied in addiction research. Maleki tells Morton:
"Interestingly, as much as pain syndromes are more prevalent in women and disproportionate relative to men, in addiction it is the opposite," she says. "Men are more likely to develop addictions, and the prevalence is higher in men. So, is the reward circuitry somehow involved in migraine pathophysiology in men? Are there overlaps between pain pathways and reward pathways? The answer is that we don't know."
Regardless, the takeaway message seems to be that migraines result in greater activation of emotional pain processing regions in women than in men. Whether these brain differences cause the migraines, or are caused by the migraines, remains to be seen.
Photo: Pierre Tourigny/Flickr