A Brain Pacemaker

Imagine walking across the street and suddenly falling down. Your
body convulses, you lose consciousness. This is how it feels to have a
seizure.

The ability to predict seizures may allow researchers to prevent
them in the near future. Scientists from the University of Florida in
Gainesville and Arizona State University (ASU) in Tempe have found that a
drop in brain wave activity precedes the onset of seizures. This
discovery could lead to the development of preemptive treatments such as
electrical implants. While brain damage from seizures is rare, attacks
can result in serious injuries, and can keep sufferers from leading
normal lives.

Leonidas Iasemidis, Ph.D., a bioengineering researcher at ASU,
envisions a computer chip that could be implanted in the brain. The
device would record brain activity and communicate via wireless
technology with an external chip that analyzes the data. If a seizure
were building, the external chip would signal the implanted chip to
administer anticonvulsant medication or an electrical shock. Iasemidis
says development of such a device could occur within five years.

Epilepsy, the brain disorder responsible for most seizures, affects
2.3 million Americans and about 50 million people worldwide. It is caused
by abnormal electrical discharges in the brain. Current methods for
treating epileptic seizures include medication and surgery to remove
brain tissue where the seizure begins.

Discovery of the pre-seizure state came from an analysis of ten
years of electroencephalograms (EEG) -- recordings of electrical activity
in the brain -- taken from epilepsy sufferers who were waiting to undergo
surgery. A change in the electrical activity in the brain was found to
precede seizures by an average of 70 to 80 minutes, and in some cases by
days. Using a mathematical formula, researchers were able to predict
around 80 percent of seizures.

If prevention does not prove possible, researchers believe there is
potential for a warning system that could alert doctors and patients to
an imminent seizure.