Structural and functional abnormalities in relevant brain regions of patients with insomnia disorders: a systematic review and multimodal neuroimaging meta-analysis.

Objective: Insomnia disorder (ID) has emerged as a significant public health concern in recent years. Research has demonstrated that the occurrence of ID is associated with abnormalities in brain structure and function. However, a consistent conclusion regarding the convergent changes in brain function and structure in individuals with ID has yet to be reached. Therefore, the purpose of this study is to synthesize previous researches through meta-analysis to investigate the changes in imaging-based cerebral structure and function of patients with ID.

Methods: We searched the PubMed, MEDLINE, and Web of Science databases for studies published as of October 28, 2024, which involved differences in cerebral gray matter volume (GMV) or spontaneous neural activity (represented by amplitude of low frequency fluctuation, ALFF) between ID patients and HC. The effective peak coordinates and t-values corresponding to brain regions were extracted from the literature and seed-based d-mapping software was used for subsequent analysis.

Results: Compared to the HC group, ALFF of ID group was increased in the right amygdala (AMYG.R), left median network, and cingulum (DCG.L) and decreased in right cerebellar hemisphere lobule VIII. GMV of ID group was increased in the right inferior temporal gyrus (ITG.R) and right insular (INS.R) and decreased in right median network, and cingulum (DCG.R).

Conclusion: In ID patients, the areas of functional abnormality were not consistent with structural abnormality, indicating a structural-functional coupling dysfunction, but the related brain regions were both associated with cognitive impairment and emotional disorders.