Migraines affect more than 30 million individuals in the U.S. They are notoriously debilitating with symptoms including headache, dizziness, nausea, vomiting, fatigue and visual disturbances. It's long been known that light makes migraines worse, but the reason why has been unclear until recently.

In a study published in Nature Neuroscience, scientists at Beth Israel Deaconess Medical Center identified a new light-sensitive pathway in the brain that is separate from visual perception that causes sensitivity to light in both blind individuals and in individuals with normal eyesight. The findings help explain the mechanism behind why light makes migraines worse. 

The study's lead researcher Rami Burstein, PhD, Professor of Anesthesia and Critical Care Medicine at BIDMC and Harvard Medical School, says that of the 30 million Americans who suffer from migraines, nearly 85 percent of them are extremely sensitive to light, a condition known as photophobia.

It was the fact that even blind individuals who suffer from migraines were experiencing photophobia that led Burstein and first author of the study, Rodrigo Noseda, PhD, to hypothesize that signals transmitted from the retina via the optic nerve were somehow triggering the intensification of pain during migraine.

The researchers studied 20 blind people who were longtime migraine sufferers. Six of the participants could not see light at all because their eyes or their optic nerves had been damaged or surgically removed. Researchers found that light did not worsen the migraine of these participants. The 14 other blind participants could detect light, but degenerative eye diseases had left the light-sensitive rods and cones in their retinas unable to perceive images. The researchers found that for these people, light did intensify the pain of their migraines.

According to Burstein, their findings suggested that the mechanism of photophobia must involve the optic nerve, because in totally blind individuals, the optic nerve does not carry light signals to the brain.

The researchers also suspected that a group of retinal cells containing melanopsin photoreceptors (which help control biological functions including sleep and wakefulness) were critically involved in the process of light intensifying the pain of a migraine, because they are the only functioning light receptors among patients who are legally blind.

For this reason, the scientists performed a series of experiments in an animal model of migraine. After injecting dyes into the eye, they traced the path of the melanopsin retinal cells through the optic nerve to the brain, where they found a group of neurons that became electrically active within seconds.

Even when the light was removed the neurons remained activated, which the researchers say, helps explain why patients say that their migraine intensifies within seconds after exposure to light, and improves 20 to 30 minutes after being in the dark.

"Clinically, this research sets the stage for identifying ways to block the pathway so that migraine patients can endure light without pain," says Burstein.

Lifestyle and Home Remedies to Ease Pain of Migraines

Self-help remedies and lifestyle changes may make a tremendous difference to ease migraine pain.

To ease your pain, try the following:

  • Incorporate relaxation into your day. Some great options include yoga, meditation, or spending at least 30 minutes each day doing something you find relaxing such as listening to music, gardening, taking a hot bath or reading.
  • Rest with ice. If possible, rest in a dark, quiet room when you feel a migraine coming on. Place an ice pack wrapped in a cloth on the back of your neck and apply gentle pressure to painful areas on your scalp.
  • Get enough sleep but don't oversleep. According to the Mayo Clinic, the average adult needs six to eight hours of sleep a night. It's also best to go to bed and wake up at regular times.
  • Keep a headache diary. On a consistent basis, write down all the details about when, where and what led up to your migraine. This will help you learn more about what triggers your migraines and what treatment will be most effective. Discuss your findings with your doctor.


Hendrick, B. Why Light Worsens Migraine Headaches. WebMD. Jan. 12, 2010. http://www.webmd.com/migraines-headaches/news/20100112/why-light-worsens-migraine-headaches. Accessed Feb. 10, 2010.

Mayo Clinic Staff. Migraine, Lifestyle and Home Remedies. MayoClinic.com. http://www.mayoclinic.com/health/migraine-headache/DS00120/DSECTION=lifestyle-and-home-remedies. Accessed Feb. 10, 2010.

Noseda, R. Burstein, R. Kainz, V., et. al. Nature Neuroscience, 13, 239 - 245 (2010). Published online Jan. 10, 2010. http://www.nature.com/neuro/journal/v13/n2/full/nn.2475.html. Accessed Feb. 10, 2010.

Prescott, B. Study Explains Why Light Worsens Migraine Headaches. Beth Israel Deaconess Medical Center. Jan. 10, 2010. http://www.bidmc.org/News/InResearch/2010/January/Migraines.aspx. Accessed Feb. 10, 2010.

Valentine, V. Q & A: Your Questions on Migraine. NPR. May 4, 2006. http://www.npr.org/templates/story/story.php?storyId=5381403. Accessed Feb. 10, 2010.

Why Light Worsens Migraine Headaches. Science Daily. Jan. 13, 2010. http://www.sciencedaily.com/releases/2010/01/100110151323.htm. Accessed Feb. 10, 2010.