Intra and inter: Alterations in functional brain resting-state networks in patients with functional constipation

Abstract

BackgroundFunctional constipation (FCon), is a symptom-based functional gastrointestinal disorder without an organic etiology and altering brain structure and function. However, previous studies mainly focused on isolated brain regions involved in brain plasticity. Therefore, little is known about the altered large-scale interaction of brain networks in FCon.MethodsFor this study, we recruited 20 patients with FCon and 20 healthy controls. We used group independent component analysis to identify resting-state networks (RSNs) and documented intra- and inter-network alterations in the RSNs of the patients with FCon.ResultsWe found 14 independent RSNs. Differences in the intra-networks included decreased activities in the bilateral caudate of RSN 3 (strongly related to emotional and autonomic processes) and decreased activities in the left precuneus of RSN 10 (default mode network). Notably, the patients with FCon exhibited significantly decreased interactive connectivity between RSNs, mostly involving the connections to the visual perception network (RSN 7–9).ConclusionCompared with healthy controls, patients with FCon had extensive brain plastic changes within and across related RSNs. Furthermore, the macroscopic brain alterations in FCon were associated with interoceptive abilities, emotion processing, and sensorimotor control. These insights could therefore lead to the development of new treatment strategies for FCon.

Altered intrinsic functional brain architecture in patients with functional constipation: a surface-based network study

“…While previous researches have focused on subcortical regions and the limbic system instead of the visual cortex to study the gut-brain axis ( Fan et al, 2019 ; Liu et al, 2021 ). Recent studies suggested significantly aberrant alteration of brain networks involving VN in patients with FCon ( Zhang D. et al, 2022 ; Yu et al, 2023 ). Based on previous studies, the VN is associated with the identification of potentially meaningful visual stimuli for the body such as pain ( Lu et al, 2020 ; Wang et al, 2020 ; Keane et al, 2021 ).…”

“…Recent studies reported significantly aberrant changes in brain network in patients with FCon using independent component analysis (ICA). Zhang D. et al (2022) investigated the large-scale interaction of RS-fMRI brain networks in 20 FCon patients and found significant differences within the basal ganglia network (BGN), DMN, and between resting-state networks (RSNs), particularly involving connections to VN. A recent publication investigated the differences in RSNs and further analyzed the alterations in FC between RSNs in a cohort of 39 female patients with FCon and 36 female HC.…”