Brain functional network characteristics of chronic insomnia patients based on sleep EEG analysis

ObjectiveThis study investigates the sleep architecture of patients with chronic insomnia and the characteristics of brain functional networks across different sleep stages (N2, N3, REM) using polysomnography (PSG) and sleep electroencephalography (EEG) parameters, aiming to explore the underlying neural mechanisms and provide evidence for precision treatment.MethodsA total of forty patients with chronic insomnia and thirty healthy controls were enrolled. Whole-night PSG data were collected to calculate standard sleep parameters. EEG signals from N2, N3, and REM stages were extracted for power spectral analysis. Power spectral density of each frequency band (delta, theta, alpha, beta) was computed in the frontal, central-parietal, and occipital regions. In addition, functional connectivity strength of 15 key electrode pairs was calculated using coherence analysis, and brain functional connectivity matrices were constructed for group comparisons.ResultsThe insomnia group showed significantly decreased sleep time [(358.10 ± 46.34) min vs. (416.89 ± 45.24) min] and N3 stage duration [(76.60 ± 25.69) min vs. (102.27 ± 26.35) min] as well as prolonged wake time (W stage) [(82.97 ± 38.66) min vs. (52.12 ± 32.24) min] (PPPPConclusionIndividuals with insomnia exhibit reduced deep sleep and cortical hyperarousal, accompanied by decreased slow-wave activity, increased fast-wave activity, and abnormal fronto-occipital network connectivity. These EEG features suggest that the neural basis of insomnia may involve impaired sleep-related cognitive processing, highlighting the close association between insomnia and cognitive dysfunction.