Article published by News Medical Life Science
Sleeping patterns and stress hormones could be the key to understanding how and when people with epilepsy are likely to experience seizures, a new study reveals. Classically, seizures were assumed to occur at random until the discovery of rhythms of epileptiform discharge (ED) activity in individuals with epilepsy that vary from hours to months. Researchers used mathematical modeling to understand the impact of different physiological processes, such as sleep and changes in concentration of the stress hormone cortisol, on ED signatures from 107 people with idiopathic generalized epilepsy. The researchers discovered two subgroups with distinct distributions of ED: one group had the highest incidence during sleep and the other during daytime. ED frequency increased during the night, early in the morning, and in stressful situations in many people with epilepsy. The researchers’ mathematical model described the activity of connected brain regions, and how the excitability of these regions can change in response to different conditions such as between sleep stages or variation in the concentration of cortisol. Their findings reveal that either the dynamics of cortisol or sleep stage transition, or a combination of both, explained most of the observed distributions of ED and may provide a framework for better understanding the timing of seizure activity.