Halos, auras, flashes of light, pins and needles running down your arms, the sudden scent of sulphur—many symptoms of a migraine have vaguely mystical qualities, and experts remain puzzled by the debilitating headaches’ cause. Researchers at Harvard University, however, have come at least one step closer to figuring out why women are twice as likely to suffer from chronic migraines as men. The brain of a female migraineur looks so unlike the brain of a male migraineur, asserts Harvard scientist Nasim Maleki, that we should think of migraines in men and women as “different diseases altogether.”

Maleki is known for looking at pain and motor regions in the brain, which are known to be unusually excitable in migraine sufferers. In one notable study published in the journal Brain in 2012, she and her colleagues exposed male and female migraineurs to painful heat on the backs of their hands while imaging their brains with functional MRI. She found that the women had a greater response in areas of the brain associated with emotional processing, such as the amygdala, than did the men. Furthermore, she found that in these women, the posterior insula and the precuneus—areas of the brain responsible for motor processing, pain perception and visuospatial imagery—were significantly thicker and more connected to each other than in male migraineurs or in those without migraines.

In Maleki’s most recent work, presented in June at the International Headache Congress, her team imaged the brains of migraineurs and healthy people between the ages of 20 and 65, and it made a discovery that she characterises as “very, very weird.” In women with chronic migraines, the posterior insula does not seem to thin with age, as it does for everyone else, including male migraineurs and people who do not have migraines. The region starts thick and stays thick.

It is not yet known whether the thickening of the insula is something the brain is doing to protect itself or something that worsens women’s migraines. Yet the evidence is mounting that when it comes to migraines, men’s and women’s brains are structurally and functionally different. For treatment, that knowledge could make a huge impact: not only should researchers be better about testing potential migraine drugs on men and women separately, Maleki says, but they may be able to design new treatments based on these brain differences—giving both sexes a better chance at relief.

Migraines can be debilitating, and most people know somebody who regularily suffers from them. Here are the top (scientifically proven) triggers:

■ Overuse of painkillers

■ Foods:

• • Processed, fermented, pickled or marinated foods
  • Chocolate, nuts, peanut butter and dairy products
  • Foods containing tyramine: red wine, aged cheese, smoked fish, chicken livers
  • Fruits and vegetables: avocadoes, bananas, citrus fruits, onions
  • Meats containing nitrates: bacon, hot dogs, salami, cured meats

■ Changes in hormones, such as menstruation

■ Sex

■ Atypical sleep patterns

 

Deciphering Cluster Headaches

Migraines are not the only culprits when it comes to extraordinary head pain. Cluster headaches have long puzzled researchers, too, although studies are slowly revealing the parts of the brain involved when those punctuated bursts of pain occur.

The excruciating headaches tend to turn up in bouts lasting six to eight weeks. During these cycles, afflicted individuals—more often men—experience intense daily headaches on one side of the head, each lasting an hour or two.

In the late 1990s Goadsby and his colleagues linked cluster headaches to heightened synaptic activity falling in or near the hypothalamus, a brain region that mediates hunger, thirst, sleep, sex drive and more. Yet researchers are still trying to understand how activity in this hypothalamus-adjacent area could conjure the condition—and to determine what other glitches in brain structure, metabolism or interactions contribute to sufferers’ throbbing heads.

At least one study suggests that in cluster headache sufferers this hypothalamus-adjoining region may differ not only in its electrical activity but also in its interactions with other parts of the brain. In February 2013, a Beijing-based team imaged the brains of a dozen men in the midst of cluster headache bouts. The researchers traced blood flow—and, with it, functional connections—between the hypothalamus and other parts of the brain. Compared with unaffected men, the cluster headache sufferers did have unusual hypothalamic connections. When headaches hit, these altered interactions often involved parts of the brain associated with pain processing. But hypothalamic connections were off-kilter between headaches, too, pointing to more persistent brain differences in those prone to cluster headaches.