Mapping the Neural Dynamics of Light Sleep: EEG Microstates and fMRI Network Correlations in N1 and N2 Stages

Motivation: While the significance of light sleep in health is gradually acknowledged, yet the specific neural dynamics during this phase is unclear. Our research emphasizes EEG microstates as vital markers of light sleep's brain networks, crucial for therapeutic innovation. Goal(s): We aimed to delineate the relationship between EEG microstates and corresponding fMRI networks during N1 and N2 sleep stages. Approach: We combined EEG-fMRI with custom regressors and GLM analysis, alongside Group-ICA, to model BOLD responses linked to EEG microstates. Results: Microstate D showed significantly lower activity across parameters in both sleep stages, with BOLD patterns revealing unique neural correlations for each microstate. Impact: This study sheds light on sleep's neural intricacies via fMRI, linking EEG microstates to brain networks, with implications for sleep disorder diagnosis, treatment, and overall sleep quality improvement.