How Does Vagal Nerve Stimulation Control Seizures?
The exact mechanism by which VNS prevents or inhibits seizure formation is currently unknown. However, what is known is that VNS works by interfering with the electrical activity of the brain. Epileptic seizures are associated with highly synchronized, characteristic patterns of brain wave activity. The vagus nerve disrupts these synchronized brain wave patterns by providing a sudden stimulation to the vagal nerve, which carries the impulse from the neck back up to the brain. Therefore, with every stimulation from the pulse generator, epileptic electrical activity may be interrupted, thus preventing a seizure before it occurs. This would explain why manually activating the pulse generator (with a hand-held magnet) at the onset of an aura is often effective at preventing progression to a seizure. VNS Surgery Implanting the VNS battery in a patient and connecting it to the vagus nerve takes approximately an hour. The procedure is usually done under general anesthesia, and can be done on
