Non-invasive temporally resolved tracking of excitation-inhibition balance during sleep via EEG

Description

Sleep is a heterogeneous state during which the brain not only switches between several stages but also shifts between different microstates within each sleep stage. These fluctuations between brain states are essential for numerous processes that occur during sleep, which render sleep essential for survival and normal functioning during wakefulness periods. Until now, however, the neural activity underling these different (micro-) states as well as those that facilitate the transition between them remains elusive. In this study, we aimed at investigating the dynamics of cortical activity during sleep in a temporally resolved manner to explain the heterogeneity of brain activity between as well as within sleep stages. We employed a recently developed open-access toolbox that extracts aperiodic brain activity from the electrophysiological signal, the slope of which reflects the interaction between excitatory and inhibitory processes in the cortex, often termed Excitation-Inhibition (EI) ratio. We used a dataset in which we recorded polysomnography (PSG) data from 17 healthy human subjects during a full night of sleep. We extracted the aperiodic component of the electroencephalography (EEG) signal in a temporally resolved manner to describe differences in EI ratio not only between sleep stages but also within them. We aim at establishing a causal relationship between fluctuations in the EI ratio and the transitions between different sleep stages as well as the appearance of certain sleep-specific events. This will help us to more efficiently track and manipulate the various essential processes that occur at specific time points during sleep.

Period	11 Feb 2022
Event title	5th Wintersymposium on "Sleep, Cognition and Consciousness"
Event type	Conference
Location	Werfenweng, AustriaShow on map
Degree of Recognition	International