Difference in regional neural fluctuations and functional connectivity in Crohn’s disease: a resting-state functional MRI study

Abstract

Patients with Crohn's disease (CD) are shown to have abnormal changes in brain structures. This study aimed to further investigate whether these patients have abnormal brain activities and network connectivity. Sixty patients with CD and 40 healthy controls (HCs) underwent resting-state functional magnetic resonance imaging (fMRI) scans. Amplitude of low-frequency fluctuation (ALFF) and seed-based functional connectivity (FC) were used to assess differences in spontaneous regional brain activity and functional connectivity. Compared to the HCs, patients with CD showed significantly higher ALFF values in hippocampus and parahippocampus (HIPP/paraHIPP), anterior cingulate cortex, insula, superior frontal cortex and precuneus. The ALFF values were significantly lower in secondary somatosensory cortex (S2), precentral gyrus, and medial prefrontal cortex. Functional connectivities between left HIPP and left inferior temporal cortex, and right middle cingulate cortex, HIPP, and fusiform area were significantly lower. The functional connectivities between right HIPP and right inferior orbitofrontal cortex and left HIPP were also significantly lower. Patients with CD showed higher or lower spontaneous activity in multiple brain regions. Altered activities in these brain regions may collectively reflect abnormal function and regulation of visceral pain and sensation, external environmental monitoring, and cognitive processing in these patients. Lower functional connectivity of the hippocampus-limbic system was observed in these patients. These findings may provide more information to elucidate the neurobiological mechanisms of the disease.

Brain Resting-State Network Alterations Associated With Crohn's Disease

“…Altered pre-frontal cortex FC is consistent with previous studies of CD including differences in amplitude of low-frequency fluctuations (29), in regional homogeneity for CD patients without pain (28), and in relation to effective treatment (30). The altered FC between anterior (MPFC) and posterior (LP) nodes within the DMN is also consistent with previous work (29). Although reduced GM volume of MPFC for CD as compared to HC has also been reported (23), this finding was not reproduced in the current study.…”

“…Studies of brain structure in CD may be in agreement on one result, altered gray matter (GM) of the superior frontal gyrus, although laterality and direction of alteration are inconsistent (22)(23)(24). Studies of brain function in CD have reported numerous FC alterations with very little overlap (25)(26)(27)(28)(29)(30)(31)(32) aside from some agreement on changes in brain networks or regions involved in executive function and/or default mode (26,30,32). Our study aimed to identify brain structural and functional changes in CD as compared to HC.…”

Changes in the anterior cingulate cortex in Crohn’s disease: A neuroimaging perspective

“…Their finding suggests a decreased ability to mediate visceral sensation. Building upon the evidence that long‐term inflammation causes alterations in the brain (Kim et al., 2019) and may impact functional results, Bao et al (2018) used other methods, including ALFF and FC, to assess anomalies in the intrinsic activity of the brain after scanning 60 patients with CD. Their study revealed increase in ALFF value in the ACC, further highlighting the role of the ACC in CD symptoms, such as visceral pain.…”

Cerebral Functional Manipulation of Repetitive Transcranial Magnetic Stimulation in Cognitive Impairment Patients After Stroke: An fMRI Study

“…Although the brain is constrained by the anatomical skeleton, the activities of each node and functional connectivity between any two nodes within these networks are dynamic ( 48 ). By means of spontaneous low-frequency oscillations in the blood oxygenation level-dependent (BOLD) signal, the resting-state functional magnetic resonance imaging (rs-fMRI) has provided a task-free approach which could eliminate some performance-related confoundings and provide a reliable measure of “baseline” brain activity and connectivity ( 49 ). Therefore, with the help of rs-fMRI, this study focused on characterizing how the cognitive-related networks dynamically change to unravel the mechanisms of cognition recovery after rTMS treatment.…”