April 20, 2022

Whole-Brain Preclinical Study Illuminates How Epileptic Seizures Originate

Article published by ScienceDaily

New evidence from a zebrafish model of epilepsy may help resolve a debate into how seizures originate, according to Weill Cornell Medicine and NewYork-Presbyterian investigators. The findings may also be useful in the discovery and development of future epilepsy drugs.

In the study, published Feb. 23 in Brain, the researchers were able to track the activities of neurons throughout the entire brains of larval zebrafish during seizures. They showed that the seizures originated from an excess of “excitatory” over “inhibitory” brain cell activity in relatively confined regions of the brain and spread only when they overcame strong inhibitory activity in surrounding regions.

Neurons in the brain come in two broad categories: excitatory neurons whose activity stimulates the activity of other neurons, and inhibitory neurons whose activity quiets other neurons. Some recent studies have indicated that surges in the activity of inhibitory neurons can paradoxically trigger seizures. The new findings suggest otherwise.

“What’s really nice about the zebrafish model is that we can image every brain region, and in this model, for the first time, we were able to distinguish and track the activity of both excitatory and inhibitory neurons,” said first author Dr. James Niemeyer, a postdoctoral associate in neurological surgery at Weill Cornell Medicine. “So, this is a good starting point for examining the nuanced roles of these cell types during seizures.”