Reduced vmPFC-insula functional connectivity in generalized anxiety disorder: a Bayesian confirmation study

Abstract

Differences in the correlated activity of networked brain regions have been reported in individuals with generalized anxiety disorder (GAD) but an overreliance on null-hypothesis significance testing (NHST) limits the identification of disorder-relevant relationships. In this preregistered study, we applied both a Bayesian statistical framework and NHST to the analysis of resting-state fMRI scans from females with GAD and matched healthy comparison females. Eleven a-priori hypotheses about functional connectivity (FC) were evaluated using Bayesian (multilevel model) and frequentist (t-test) inference. Reduced FC between the ventromedial prefrontal cortex (vmPFC) and the posterior-mid insula (PMI) was confirmed by both statistical approaches and was associated with anxiety sensitivity. FC between the vmPFC-anterior insula, the amygdala-PMI, and the amygdala-dorsolateral prefrontal cortex (dlPFC) region pairs did not survive multiple comparison correction using the frequentist approach. However, the Bayesian model provided evidence for these region pairs having decreased FC in the GAD group. Leveraging Bayesian modeling, we demonstrate decreased FC of the vmPFC, insula, amygdala, and dlPFC in females with GAD. Exploiting the Bayesian framework revealed FC abnormalities between region pairs excluded by the frequentist analysis and other previously undescribed regions in GAD, demonstrating the value of applying this approach to resting-state FC data in clinical investigations.

Are the Post-COVID-19 Posttraumatic Stress Disorder (PTSD) Symptoms Justified by the Effects of COVID-19 on Brain Structure? A Systematic Review

“…Due to the restricted time of the COVID-19 pandemic and the recent time period involved in these studies, this was to be expected (i.e., recent studies are expected to be more methodologically sound). It should also be stressed that some of the alterations that we found to be shared among ptsD patients and survivors of COVID-19 infection (PFC, ACC, insula, and hippocampus) may also be found in patients with emotional disturbances, like anxiety and depressive disorders [81][82][83][84][85], and even in severe psychotic disorders, like schizophrenia [86]. With these disturbances and disorders all having a shared background with childhood trauma and adversity [87][88][89], it is almost impossible to disentangle what is specific to ptsD and COVID-19 and what could be nonspecific.…”

Microbiota–gut–brain axis: the mediator of exercise and brain health

“…Patients with GAD exhibited decreased microbial quantity and diversity, along with distinct metagenomic composition, suggesting microbiota dysbiosis in GAD patients (Jiang et al ., 2018 ). According to fMRI results, frontal lobe lesions causing a loss of functional connectivity between cortical areas such the insula, amygdala, anterior cingulate cortex, medial temporal, and prefrontal cortex (PFC) are characteristics of anxiety disorders (Fonzo, Etkin, 2017 ; Kenwood et al ., 2022 ; Steinhäuser et al ., 2023 ). Machine learning studies using fMRI as a feature have demonstrated the capacity to differentiate patients with anxiety disorders and healthy individuals within the controlled group.…”