Relieving Migraine Pain
March 26, 2008
The intense, throbbing pain of a migraine often feels like an attack on the senses. In Germany, some 12 percent to 16 percent of the population suffers from migraines, which can affect one or both sides of the head. But some sufferers experience a kind of warning, known as an "aura," before the full-blown attack.
Scientists, however, remain at odds over whether an aura is the cause of migraine pain, or an accompanying symptom since migraines can occur with or without auras. The auras themselves also do not necessarily develop into migraines.
An aura is a kind of psychological or neurological "churning" lasting from five minutes to 30 minutes and which can result in vertigo, confusion, or numbness, and can also affect vision in various ways. Visual disturbances, such as vision loss, or hallucinations may result, including flashing lights, distortion of objects or the emergence of complex color patterns.
Malfunction in visual cortex
Auras involving visual disturbances often intrigue doctors because they are so mysterious.
Scientists have known for the past few years that such auras are linked with a so-called stimulation wave. This involves increased activity of brain cells that occurs in the visual cortex and which moves at the rate of three millimeters (0.118 inches) per minute. A malfunction in the visual cortex, however, makes aura sufferers see something in their line of vision which does not really exist.
A 30-minute-aura could prove fatal since someone suffering from one behind the wheel could perceive an empty street when in fact a cyclist is passing by.
Faulty feedback mechanisms
Using computer simulations, physicists are now trying to figure out what triggers an aura.
The simulations do not try to replicate the entire brain in a computer, but instead, some of its decisive mechanisms.
"Those include the neurons grouped in the visual cortex which are connected to one another in multiple ways," said Eckehard Schoell, managing director of the Institute for Theoretical Physics in Berlin. "When electrical pulses move along these connections, we have what we call a stimulation wave."
Particularly important here is the ability of brain cells to both send and receive signals. Cells can thus communicate with other cells and send back or pass on the information they have just received.
The physicists in Berlin have tracked precisely these signals in their computer simulations.
"Let's assume that this feedback mechanism is occurring and our model is currently in an area where no waves can develop -- that would be the model of a healthy patient," Schoell said. "If we were to now suppress this feedback mechanism from occurring, then we suddenly move into an area where waves can occur."
One could then assume that a lack of feedback mechanisms is what causes the stimulation waves and thus migraine auras.
Glasses may solve problem
Some scientists are now speculating that artificial means could help trigger the missing feedback processes, with experts at the Juelich Research Center in western Germany placing their bets on an unusual pair of glasses.
Special sensors attached to the glasses at the back of the head can measure brain activity. Their signals can control diodes which are located on the front of the glasses and which produce bright, flashing lights that influence the activity of neurons in the brain.
The goal is that the flashing lights from the glasses would hinder the stimulation waves, thereby suppressing auras and hopefully the migraines as well.
While the glasses have so far only been tested on healthy patients, scientists are optimistic about the results. But whether they can actually help suppress auras and even migraines in sufferers remains to be seen.