Wheelock Muriah D, Rangaprakash Deshpande, Harnett Nathaniel G, Wood Kimberly H, Orem Tyler R, Mrug Sylvie, Granger Douglas A, Deshpande Gopikrishna, Knight David C
Department of Psychology, University of Alabama at Birmingham.
MRI Research Center and Department of Electrical and Computer Engineering, Auburn University.
Behav Neurosci. 2018 Dec;132(6):561-572. doi: 10.1037/bne0000276. Epub 2018 Oct 25.
Cognitive and emotional functions are supported by the coordinated activity of a distributed network of brain regions. This coordinated activity may be disrupted by psychosocial stress, resulting in the dysfunction of cognitive and emotional processes. Graph theory is a mathematical approach to assess coordinated brain activity that can estimate the efficiency of information flow and determine the centrality of brain regions within a larger distributed neural network. However, limited research has applied graph-theory techniques to the study of stress. Advancing our understanding of the impact stress has on global brain networks may provide new insight into factors that influence individual differences in stress susceptibility. Therefore, the present study examined the brain connectivity of participants that completed the Montreal Imaging Stress Task (Goodman et al., 2016; Wheelock et al., 2016). Salivary cortisol, heart rate, skin conductance response, and self-reported stress served as indices of stress, and trait anxiety served as an index of participant's disposition toward negative affectivity. Psychosocial stress was associated with a decrease in the efficiency of the flow of information within the brain. Further, the centrality of brain regions that mediate emotion regulation processes (i.e., hippocampus, ventral prefrontal cortex, and cingulate cortex) decreased during stress exposure. Interestingly, individual differences in cortisol reactivity were negatively correlated with the efficiency of information flow within this network, whereas cortisol reactivity was positively correlated with the centrality of the amygdala within the network. These findings suggest that stress reduces the efficiency of information transfer and leaves the function of brain regions that regulate the stress response vulnerable to disruption. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
认知和情感功能由大脑区域分布式网络的协同活动支持。这种协同活动可能会因心理社会压力而中断，导致认知和情感过程功能失调。图论是一种评估大脑协同活动的数学方法，它可以估计信息流的效率，并确定大脑区域在更大的分布式神经网络中的中心性。然而，将图论技术应用于压力研究的相关研究有限。深入了解压力对全脑网络的影响，可能会为影响个体压力易感性差异的因素提供新的见解。因此，本研究考察了完成蒙特利尔成像应激任务（古德曼等人，2016年；惠洛克等人，2016年）的参与者的大脑连通性。唾液皮质醇、心率、皮肤电传导反应和自我报告的压力作为压力指标，特质焦虑作为参与者对消极情感倾向的指标。心理社会压力与大脑内信息流效率的降低有关。此外，在压力暴露期间，介导情绪调节过程的大脑区域（即海马体、腹侧前额叶皮质和扣带回皮质）的中心性降低。有趣的是，皮质醇反应性的个体差异与该网络内信息流的效率呈负相关，而皮质醇反应性与杏仁核在网络中的中心性呈正相关。这些发现表明，压力会降低信息传递的效率，并使调节压力反应的大脑区域功能容易受到破坏。（《心理学文摘数据库记录》（c）2018年美国心理学会，保留所有权利）
