Thalamocortical coherence and causality in different sleep stages using deep brain stimulation recordings
Fleur E N B Jacobs1, Hannah Bernhard2, Vivianne H J M van Kranen-Mastenbroek3
1Department of Clinical Neurophysiology, Maastricht University Medical Center, Maastricht University, Maastricht, Netherlands.
Sleep Medicine
|November 3, 2022
Summary
This study reveals that during non-rapid eye movement (NREM) sleep, brain activity flows predominantly from the cortex to the thalamus. This thalamocortical connectivity remains stable in direction across NREM sleep stages.
Area of Science:
- Neuroscience
- Sleep Science
- Brain Connectivity
Background:
- Thalamocortical interactions are crucial during non-rapid eye movement (NREM) sleep.
- The directionality of synchronization between the thalamus and cerebral cortex during NREM sleep remains unclear.
Purpose of the Study:
- To investigate the directionality of thalamocortical connectivity during human NREM sleep stages.
- To determine if connectivity strength or direction varies across NREM sleep stages (N1, N2, N3).
Main Methods:
- Utilized scalp electroencephalograms (EEGs) and local field potentials (LFPs) from anterior thalamus in three epilepsy patients.
- Assessed connectivity using debiased weighted phase lag index (d-wPLI) and Granger causality.
- Analyzed connectivity across NREM sleep stages N1, N2, and N3.
Main Results:
- Connectivity was predominantly directed from the cortex to the thalamus.
- Connectivity strength varied significantly across different NREM sleep stages.
- The direction and frequency of connectivity showed minimal variation between sleep stages.
Conclusions:
- Thalamocortical connectivity during NREM sleep is primarily directed from the cortex to the thalamus.
- This directional flow appears relatively stable throughout NREM sleep stages.
- Findings contribute to understanding brain dynamics during sleep.
