Visual 'Noise' May Overexcite Those With Migraine
FRIDAY April 16, 2010 -- Migraine sufferers appear to have more trouble ignoring visual distractions than other people, a new study suggests.
Researchers asked migraine sufferers to pick out a small disk of light when it was presented with and without visual noise -- an effect similar to the black-and-white snow on an off-air television.
Without the visual noise, people with migraine were able to pick out the light disk as well as migraine-free people. But the migraine sufferers (migraineurs) did significantly worse when the visual noise was added, the study found. The visual noise had the most impact on those who experience visual auras before a migraine.
"Our visual environment is generally very busy and full of objects, many of which are important at some times but not at others. Normally, we can attend effortlessly to those items of interest and often do not even notice others," lead researcher Doreen Wagner, of Glasgow Caledonian University in Scotland, said in a news release. "Migraineurs may be at a disadvantage when searching for details, especially in cluttered environments."
A current theory about migraines suggests that nerve cells in the brains of migraine sufferers are excitable, and exposure to certain triggers causes whole clusters of brain cells to become overactive, resulting in a migraine.
"We believe that the [visual] noise on the display overexcites the nerve cells in the brain of the migraineurs. This in turn makes it harder for a migraineur to see the disk," Wagner said.
The findings may prove useful for migraine sufferers, the researchers said.
"It might be helpful to avoid such 'noisy' environments which may impair their performance, scenes overloaded with visual distracters," Wagner said. These might include computer screens and learning tools which have a lot of visual information on them, she said.
The study appears in the April issue of the journal Investigative Ophthalmology & Visual Science.
The U.S. National Institute for Neurological Disorders and Stroke has more about migraine.
Posted: April 2010