Clinical Psychopharmacology and Neuroscience Papers in Press available online.

Hyperarousal-State of Insomnia Disorder in Wake-Resting State Quantitative Electroencephalography
Gyutae Jang1, Han Wool Jung 1, Jiheon Kim1,2, Hansol Kim1, Ji-Hyeon Shin3, Chan-Hyung Kim4, Do-Hoon Kim1,2, Sang-Kyu Lee2, Daeyoung Roh 1,2,*
1Mind-Neuromodulation Laboratory, Hallym University College of Medicine, 2Department of Psychiatry, Hallym University College of Medicine, 3Department of Otolaryngology-Head and Neck Surgery, College of Medicine, The Catholic University of Korea, 4Department of Psychiatry and Institute of Behavioural Science in Medicine, Yonsei University College of Medicine
Insomnia is associated with elevated high-frequency electroencephalogram power in the waking state. Although affective symptoms (e.g., depression and anxiety) are commonly comorbid with insomnia, few reports distinguished objective sleep disturbance from affective symptoms. In this study, we investigated whether daytime electroencephalographic activity explains insomnia, even after controlling for the effects of affective symptoms. A total of 107 participants were divided into the insomnia disorder (n = 58) and healthy control (n = 49) groups using the Mini-International Neuropsychiatric Interview and diagnostic criteria for insomnia disorder. The participants underwent daytime resting-state electroencephalography sessions (64 channels, eye-closed). The insomnia group showed higher levels of anxiety, depression, and insomnia than the healthy group, as well as increased beta [t(105) = -2.56, p = 0.012] and gamma [t(105) = -2.44, p = 0.016] spectra. Among all participants, insomnia symptoms positively correlated with the intensity of beta (r = 0.28, p < 0.01) and gamma (r = 0.25, p < 0.05) spectra. Through hierarchical multiple regression, the beta power showed the additional ability to predict insomnia symptoms beyond the effect of anxiety (ΔR2 = 0.041, p = 0.018). Our results showed a significant relationship between beta electroencephalographic activity and insomnia symptoms, after adjusting for other clinical correlates, and serve as further evidence for the hyperarousal theory of insomnia. Moreover, resting-state quantitative electroencephalography may be a supplementary tool to assess insomnia.
Accepted Manuscript [Submitted on 2023-02-07, Accepted on 2023-03-15]