These patients have slow brain wave activity during wakefulness, which can reduce the firing of nerve cells to protect against the pathology of epilepsy.
Researchers discovered that the brains of people with epilepsy might have a mechanism for reducing risk of epileptic activity, according to investigators at University College London who published their research in Nature Communications. In this study, researchers learned that these patients’ brains emit slow waves—which usually occur during sleep in people without epilepsy— while they are awake. This may counter brain excitability and reduce the risk of adverse activity.
“This study unveils, for the first time, a potential protective mechanism, ‘wake’ slow waves, employed by the brain to counteract epileptic activity,” said senior study author Matthew Walker, MD, PhD, professor of neurology, Department of Clinical and Experimental Epilepsy, University College London, in the press release.
Brain excitability that occurs during the day is remedied in sleep when slow waves occur, according to Walker. This is partly why sleep is so important; it repairs and resets brain activity to restore proper brain function. For this reason, the study aimed to identify if these slow waves which naturally occur during sleep are used to combat epileptic brain activity during wakefulness.
Investigators enrolled 25 people with focal epilepsy, which is characterized by seizures caused by a certain part of the brain. Using an electroencephalogram (EEG), the investigators scanned the patients’ brains while they performed a memory task. The EEG data showed that these patients’ brains were producing slow waves while they were awake (“wake” slow waves), and the frequency of wake slow waves increased as the patients’ brains became excited during the task.
While the brain is able to create a mechanism that reduces pathological activities, this can come at a price, explained lead author Laurent Sheybani, MD, PhD, senior research fellow, Department of Clinical and Experimental Epilepsy, University College London. “’Wake’ slow waves are shown to [have an] impact on memory performance,” Sheybani said in the press release.
Slow waves were shown to affect memory by reducing nerve cell activity. For every second a person experienced 1 increase in slow waves, their reaction time increased 0.56 seconds. Thus, these slow waves can contribute to cognitive difficulties, Walker explained.
The electrodes, which were originally used to localize the abnormal brain activity, also revealed a new insight on sleep activity in general.
“From a purely neurobiological perspective, the research also reinforces the idea that sleep activity can happen in specific areas of the brain, rather than occurring evenly throughout the brain,” Sheybani said in the press release.
Moreover, future studies are aimed at continuing to study the impact of slow waves in people with epilepsy, which could be used to help create therapeutic targets.
“The parallel between the function of slow waves during sleep and their beneficial impact in a pathological condition is particularly interesting,” Sheybani said in the press release.
Brain waves usually found in sleep can protect against epileptic activity. University College London. News Release. November 30, 2023. Accessed on November 30, 2023. https://www.eurekalert.org/news-releases/1009340