SciTech

CMU and Berkeley scientists looking for safer seizure suppression

Credit: India Price/Editor-in-Chief Credit: India Price/Editor-in-Chief

An epileptic seizure is caused when there is abnormal and excessive amounts of brain activity. The seizure is basically a sudden burst brain activity from a collection of brain cells, which creates a very high energy wave that affects the brain and the immediate surrounding tissue. The effects of an epileptic seizure are varied. While some can be mild or controlled, others can manifest themselves as uncontrollable jerking movements, excrutiating pain, extreme exhaustion, and momentary loss of awareness.

Proneness to seizures may result from a variety brain disorders or diseases that increase the probability of there being a seizure (epilepsy), but can also be a product of drug use, brain trauma, very high body temperature, low blood sugar, and low body oxygen levels. According to the Carnegie Mellon University press release of this research, patients of epilepsy often reduce the impact of their seizures or suppress them by taking medication, avoiding triggers, and adhering to a specified diet, among other practices. Sometimes, patients whose seizures are harder to control or become exceedingly difficult to handle can choose to undergo surgery to have certain portions of their cortex removed or have neurotransmitters implanted there. These procedures, though often beneficial, are quite invasive.

Maysam Chamanzar, a professor of electrical and computer engineering at Carnegie Mellon University, Reza Alam, a professor of mechanical engineering at University of California, Berkeley, and Ben Zhang, a Ph.D. student at University of California, Berkeley recently published a paper in the Journal of the Royal Society Interface. The paper explains an alternative method to suppress seizures in a non-invasive way. The method uses Anderson localization, where a wave phenomenon occurs in the absence of waves in a disordered medium. According to the press release, Chamanzar explains this phenomenon as similar to the way ocean waves lose energy when they move over a random and irregular topography. This phenomenon is applicable to all waves, including large optical waves or fast-moving light waves, and was discovered in a solid-state physics base context by Nobel laureate P.W. Anderson.

In the paper, Chamanzar and his colleagues aim to prove the validity of using this phenomenon with brain waves. They hypothesize that if one considers that seizures are a synchronized set of brain waves that propagate across the brain surface, then, one can ideally attempt to disrupt this spread by locally modulating neurons hypothetically using a phased array of ultrasound transducers. This would create several nodes, which disrupt the spread of the brain waves that cause the seizure by making them lose energy. The team expects to test this procedure by having patients wear a head device in the form of a cap or a headset that would launch a random pattern of ultrasound waves when a seizure onset was detected. This method is especially significant because it is an immediate and non-invasive response to a seizure.