Ince Sevil, Steward Trevor, Harrison Ben J, Jamieson Alec J, Davey Christopher G, Agathos James A, Moffat Bradford A, Glarin Rebecca K, Felmingham Kim L
Melbourne School of Psychological Sciences, The University of Melbourne, Parkville, Victoria, 3010, Australia; Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne, Parkville, Victoria, 3010, Australia.
Melbourne School of Psychological Sciences, The University of Melbourne, Parkville, Victoria, 3010, Australia; Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne, Parkville, Victoria, 3010, Australia.
Neuroimage. 2023 Apr 15;270:119964. doi: 10.1016/j.neuroimage.2023.119964. Epub 2023 Feb 22.
Core regions of the salience network (SN), including the anterior insula (aINS) and dorsal anterior cingulate cortex (dACC), coordinate rapid adaptive changes in attentional and autonomic processes in response to negative emotional events. In doing so, the SN incorporates bottom-up signals from subcortical brain regions, such as the amygdala and periaqueductal gray (PAG). However, the precise influence of these subcortical regions is not well understood. Using ultra-high field 7-Tesla functional magnetic resonance imaging, this study investigated the bottom-up interactions of the amygdala and PAG with the SN during negative emotional salience processing. Thirty-seven healthy participants completed an emotional oddball paradigm designed to elicit a salient negative emotional response via the presentation of random, task-irrelevant negative emotional images. Negative emotional processing was associated with prominent activation in the SN, spanning the amygdala, PAG, aINS, and dACC. Consistent with previous research, analysis using dynamic causal modelling revealed an excitatory influence from the amygdala to the aINS, dACC, and PAG. In contrast, the PAG showed an inhibitory influence on amygdala, aINS and dACC activity. Our findings suggest that the amygdala may amplify the processing of negative emotional stimuli in the SN to enable upstream access to attentional resources. In comparison, the inhibitory influence of the PAG possibly reflects its involvement in modulating sympathetic-parasympathetic autonomic arousal mediated by the SN. This PAG-mediated effect may be driven by amygdala input and facilitate bottom-up processing of negative emotional stimuli. Overall, our results show that the amygdala and PAG modulate divergent functions of the SN during negative emotional processing.
突显网络（SN）的核心区域，包括前脑岛（aINS）和背侧前扣带回皮质（dACC），可协调注意力和自主神经过程的快速适应性变化，以应对负面情绪事件。在此过程中，突显网络整合来自皮质下脑区（如杏仁核和导水管周围灰质（PAG））的自下而上的信号。然而，这些皮质下区域的确切影响尚不清楚。本研究使用超高场7特斯拉功能磁共振成像技术，调查了在负面情绪突显处理过程中杏仁核和导水管周围灰质与突显网络之间的自下而上的相互作用。37名健康参与者完成了一项情绪oddball范式，该范式旨在通过呈现随机的、与任务无关的负面情绪图像来引发显著的负面情绪反应。负面情绪处理与突显网络中的显著激活相关，包括杏仁核、导水管周围灰质、前脑岛和背侧前扣带回皮质。与先前的研究一致，使用动态因果模型的分析显示杏仁核对前脑岛、背侧前扣带回皮质和导水管周围灰质有兴奋性影响。相比之下，导水管周围灰质对杏仁核、前脑岛和背侧前扣带回皮质的活动有抑制作用。我们的研究结果表明，杏仁核可能会放大突显网络中负面情绪刺激的处理，以便上游能够获取注意力资源。相比之下，导水管周围灰质的抑制作用可能反映了其参与调节由突显网络介导的交感-副交感自主神经唤醒。这种由导水管周围灰质介导的效应可能由杏仁核输入驱动，并促进负面情绪刺激的自下而上的处理。总体而言，我们的结果表明，在负面情绪处理过程中，杏仁核和导水管周围灰质调节突显网络的不同功能。
