Linking Macroscale Resting-State Functional Connectivity to Acute and Chronic Stress
Abstract
Introduction
Stress exposure leads to an intricate psychophysical response [1]. Acute stress is triggered by a transient change in the environment and is considered adaptive. Chronic stress is characterised by a prolonged stress exposure and is considered maladaptive, and a risk factor for psychiatric disorders. Resting-state functional connectivity (rs-fc) captures task-independent neural activity [2]. Hence, it is a useful indicator of brain network organisation and is heavily featured in stress research. Recently, the novel method of functional connectome gradients emerged. Adapted from spectral graph theory, it captures the multidimensionality of the cortical landscape and provides a hierarchical view on brain organisation [3]. In our explorative study, we hypothesise that there will be a link between macroscale rs-fc and acute and chronic stress.
Methods
Two overlapping datasets will be used: (1) Max Planck Institute Mind-Brain-Body Dataset - LEMON and (2) The Neural Consequences of Stress dataset (NECOS), an extension of LEMON. Within the NECOS datasets the Trier Social Stress Test was used to invoke acute stress. Within the LEMON, the Trier Inventory of Chronic stress questionnaire was obtained to assess chronic stress. To establish macroscale rs-fc, resting-state fMRI scans will be obtained from both datasets and gradient analysis will be performed using the BrainSpace toolbox in Python.
Expected Findings & Significance
We expect to see a change in macroscale organisation of rs-fc with increasing chronic stress and following acute stress intervention. Due to our analysis being primarily explorative, we cannot infer the directionality of the results. The impact of this study is two-fold: First, we aim to shed light on the applicability of the method to stress research. By looking at stress we are contributing to the current debate on the robustness of gradients across states and traits. Second, we hope to advance the knowledge of the effects of stress on functional organisation of the brain to contribute to future stress interventions, preventions, and treatments.
References
[1] F. S. Dhabhar, ‘The Short-Term Stress Response – Mother Nature’s Mechanism for Enhancing Protection and Performance Under Conditions of Threat, Challenge, and Opportunity’, Front. Neuroendocrinol., vol. 49, pp. 175–192, Apr. 2018, doi: 10.1016/j.yfrne.2018.03.004.
[2] L. Raimondo et al., ‘Advances in resting state fMRI acquisitions for functional connectomics’, NeuroImage, vol. 243, p. 118503, Nov. 2021, doi: 10.1016/j.neuroimage.2021.118503.
[3] D. S. Margulies et al., ‘Situating the default-mode network along a principal gradient of macroscale cortical organization’, Proc. Natl. Acad. Sci., vol. 113, no. 44, pp. 12574–12579, Nov. 2016, doi: 10.1073/pnas.1608282113.
