Scientists studying epilepsy at the University of Pennsylvania Medical Center are finding a pattern of human brain activity that indicates the conditions triggering seizures can take hours to develop.
The work points toward a method to short-circuit epileptic seizures and convulsions before they strike, through the use of implantable brain devices and medications, according to Brian Litt, MD, author of the study. It appears April 26 in the journal Neuron.
"This study is part of a large collaborative effort to control symptoms of a condition that dominates the lives of otherwise healthy individuals by its dramatic unpredictability," Litt said. The potential to use our findings to help people with poorly controlled seizures world-wide is enormous.
About 50 million people throughout the world suffer from epilepsy. Almost 25 percent have seizures that are not controlled by any available therapy.
Although epilepsy is the most common neurologic disease after stroke, its cause cannot be identified in a large percentage of cases. Recently, scientists looking for changes in the brain that predict seizures have had some success using mathematically-based chaos theory. But those studies have generally been limited in scope -- they concentrate on a period of minutes prior to seizures -- and are further limited by the difficulty of applying an abstract theory to what actually happens inside the brain.
Litt and his colleagues, on the other hand, relied on the traditional method of measuring brain activity through EEG (electroencephalograpy) readings for five epilepsy patients who were being evaluated for surgery and had therefore stopped taking anti-seizure medication. The EEG readings tracked the patients for periods ranging from four to 14 days.
Using electrodes implanted in both sides of the brain, the scientists examined "a continuous stream of data for reproducible patterns associated with seizures, and found a chain of events that predicted
Contact: Ellen O'Brien
University of Pennsylvania School of Medicine