Altered default mode network homogeneity in chronic insomnia disorder: modulation by modified suanzaoren decoction and estazolam, and machine learning classification.
Authors
Affiliations (6)
Affiliations (6)
- Department of Rehabilitation Medicine, Jiangbin Hospital of Guangxi Zhuang Autonomous Region, Nanning, China.
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, and National Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha 410011, Hunan, China.
- Inner Mongolia Autonomous Region Mental Health Center, Hohhot 010010, Inner Mongolia Autonomous Region, China.
- Department of Psychosomatics and Psychiatry, Zhongda Hospital, School of Medicine, Jiangsu Provincial Key Laboratory of Brain Science and Medicine, Southeast University, Nanjing 210009, China.
- Inner Mongolia Autonomous Region Mental Health Center, Hohhot 010010, Inner Mongolia Autonomous Region, China. Electronic address: [email protected].
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, and National Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha 410011, Hunan, China. Electronic address: [email protected].
Abstract
Chronic Insomnia Disorder (CID) is characterized by maladaptive self-referential thinking linked to default mode network (DMN) dysfunction. Network Homogeneity (NH), a measure of local functional integration within networks, may capture this dysregulation but remains underexplored in CID and its response to treatment, particularly herbal medicine. This study employed resting-state functional magnetic resonance imaging (fMRI) to investigate DMN NH in 82 patients with CID (52 treated with Modified Suanzaoren Decoction [MSZRD], 30 with Estazolam) and 65 matched healthy controls (HCs). NH was calculated for the DMN. Baseline differences, longitudinal treatment effects (mixed-effects model), and correlations with clinical scores were examined. A support vector machine (SVM) classifier used baseline NH features for diagnostic discrimination. At baseline, CID patients exhibited widespread abnormal NH in DMN nodes, including the temporal lobes, precuneus, and orbitofrontal cortex (OFC), compared to HCs. Post-treatment, a significant time effect (increased NH) was found in the right inferior frontal orbital gyrus (IFOG) and right superior temporal gyrus (STG) across both groups. Crucially, a group-by-time interaction was identified in the right medial frontal orbital gyrus (MFOG), where NH increased after MSZRD but decreased after Estazolam. Baseline NH in temporal regions correlated positively with insomnia and anxiety severity. The SVM classifier achieved significant accuracy in distinguishing patients from HCs. CID is characterized by dysfunctional integration within the DMN. MSZRD and Estazolam demonstrate both convergent and divergent neuromodulatory effects, with MSZRD uniquely altering NH in a key prefrontal regulatory hub.