Dynamic changes in thalamic connectivity following stress and its association with future depression severity

Abstract

IntroductionTracking stress‐induced brain activity and connectivity dynamically and examining activity/connectivity‐associated recovery ability after stress might be an effective way of detecting stress vulnerability.MethodsUsing two widely used stress paradigms, a speech task (social stress) and a mathematical calculation task (mental loading stress), we examined common changes in regional homogeneity (ReHo) and functional connectivity (FC) before, during, and after the two stressful tasks in thirty‐nine college students. A counting breath relaxation task was employed as a contrast task. ReHo and FC were compared between subjects with higher versus lower depression symptoms (assessed by the Beck Depression Inventory, BDI). We developed a recovery index (RI) based on dynamic changes of ReHo/FC to evaluate individuals' ability to recover from a stressful state. To assess RI's usefulness in predicting future depression severity, BDI was also measured at one‐year follow‐up.ResultsOur results revealed a ReHo decrease after both stressful tasks and a ReHo increase after the relaxation task in bilateral thalamus. The ReHo decrease after both stressful tasks was more significant in the higher BDI than the lower BDI group. Higher ReHo RI of the right thalamus in the higher BDI groups was significantly correlated with lower BDI severity at one‐year follow‐up. Bilateral thalamus also showed increased FC with the default mode network and decreased FC with the executive control network after the stressful tasks.ConclusionThese findings highlight the importance of tracking resting activity and connectivity of thalamus dynamically for detecting stress vulnerability.

Alterations in 18F-FDG PET/MRI and 15O-Water PET Brain Findings in Patients With Neurological Symptoms After COVID-19 Vaccination

“…The patient with a mildly significant decrease in perfusion in the bilateral thalamus and bilateral cerebellum on the 15 O-water PET did not show any abnormalities on their MRI perfusion image, which may indicate minor perfusion changes or nonspecific findings, although thalamus connectome data have suggested an association with anxiety. 15 , 16 However, the diffuse increase in perfusion in the cerebral white matter was observed on both the 15 O-water PET and MRI perfusion images. Previous studies have shown that increased cerebral blood volume and CBF can be detected in normal-appearing white matter in patients with inflammatory conditions, such as multiple sclerosis.…”

“…Symptoms experienced may include vasovagal reactions and dissociative FIGURE 2. 15 O-water and cluster subtraction (P = 0.05) images of patients with neurological symptoms for the first visit and follow-up using the MIM software. Mildly significant decreased perfusion in the bilateral thalamus (A) and bilateral cerebellum (B) in patient 6 (C, D) Mildly diffuse increased perfusion in the cerebral white matter of patient 8 was also noted on both the 15 O-water and MRI perfusion images.…”

“…All patients underwent CT, MRI, 18 F-FDG PET/MRI, and 15 O-water PET of the brain while experiencing neurological symptoms after their first COVID-19 vaccination. Each patient underwent followup 18 F-FDG PET/MRI and 15 O-water PET of the brain (median duration of 6 days; range, 4-7 days). Patients sat in a quiet room with both eyes open without covering their ears before radiotracer administration.…”

“…Erlangen, Germany). 15 O-water (800-1000 MBq) was injected (Radiowater Generator; Hidex Oy, Turku, Finland) as an intravenous bolus over 6 seconds, which was then flushed with normal saline. Dynamic acquisition was performed for 7 minutes in 3-dimensional (3D) mode immediately following the injection.…”

RETRACTED; Combined rs‐fMRI study on brain functional imaging and mechanism of RAGE‐DAMPs of depression: Evidence from MDD patients to chronic stress‐induced depression models in cynomolgus monkeys and mice

“…Research shows that there are many interrupted network connectivity in MDD core network, such as default mode network, and the limbic system and so on. 9 , 10 The analysis of functional connectivity (FC) is based on seed points and relies on a priori hypothesis. The changes of voxel activity over time (such as regional homogeneity [ReHo] and low‐frequency fluctuation amplitude [ALFF]) can help to reveal the changes of cerebral blood flow in patients with stress‐induced MDD.…”