Millions of people around the world suffer from migraines daily. The tell-tale sign of squiggly lines, blinding pains, and sensitivity to light can transform the best day into one of the worse for migraine sufferers. Those familiar with migraines know the signs of a migraine aura. Now, researchers want to use those aura indicators and possibly help migraine sufferers avoid the pain.
A team from Penn State said they've managed to identify the electrical activity associated with auras, isolated it, and have found ways to stop it in animal experiments.
"Seizures and migraines are two very different states of the brain," said Steven J. Schiff, Brush Chair Professor of Engineering in the Departments of Neurosurgery, Engineering Science and Mechanics, and Physics, Penn State. "We found that the spreading depolarization, also called spreading depression, seen in migraines is a fundamental biophysical phenomenon and you can stop it with electrical current. Strangely, it is the opposite direction of electrical current used to turn off seizures."
Schiff serves as the university's Center for Neural Engineering, and he said he and his team haven't cured migraines. However, he said the discovery gets them several steps closer to solving a problem affecting millions each year. Roughly 10 percentof men and 22 percent of women in the United States suffer from migraines, according to the US Center for Disease Control.
The team used computational models to understand the spreading depolarization in rat subjects. Their research was recently reported in an issue of Scientific Reports.
"The electrical activity in the brain causing the aura is like a rolling blackout," said Andrew J. Whalen, postdoctoral scholar, Center for Neural Engineering, Penn State. "It's not just a single cell, but a chain reaction that moves across the brain causing swelling, and it takes people a while to recover."
The Penn State team already knew that salt concentrations in the brain can alter the brain's electrical functions thanks to previous research. By altering the potassium concentrations in the brain, the team could affect the rate of depolarization.
"We thought that if we stopped the initial phase, the aura, we would stop the rest," said Schiff. "We finally figured out that the charge necessary to stop the spreading depression was opposite to what we assumed. Once we chose the opposite charge, the progression of the phenomena stopped. This all made sense in the end, since seizures and migraines start at opposite ends of the brain cells."
The team could use a positive charge in order to stop the spreading and end the episode in the rat brain.
"We came up with a biophysical understanding and it applies to the fundamental physiology of the aura, and we can make it worse with one current and we can make it better with the opposite current," said Schiff.
Ideally, the team wants to apply this polarization to the human brain and test it in clinical trials with migraine sufferers.
"One wants to be able to fix the brain so that it is not susceptible to migraines or seizures," said Bruce J. Gluckman, professor of engineering science and mechanics, neurosurgery and bioengineering and associate director of the Center for Neural Engineering. "Not to have to control migraines or spreading depression once it starts. For now, this is a fundamental result that moves us closer to being able to intervene in an important way for this condition."