Department of Psychology, University of Pittsburgh, Pittsburgh, PA 15260, United States.
Department of Psychology, University of Pittsburgh, Pittsburgh, PA 15260, United States.
Brain Behav Immun. 2017 May;62:162-170. doi: 10.1016/j.bbi.2017.01.013. Epub 2017 Jan 23.
The default mode network (DMN) encompasses brain systems that exhibit coherent neural activity at rest. DMN brain systems have been implicated in diverse social, cognitive, and affective processes, as well as risk for forms of dementia and psychiatric disorders that associate with systemic inflammation. Areas of the anterior cingulate cortex (ACC) and surrounding medial prefrontal cortex (mPFC) within the DMN have been implicated specifically in regulating autonomic and neuroendocrine processes that relate to systemic inflammation via bidirectional signaling mechanisms. However, it is still unclear whether indicators of inflammation relate directly to coherent resting state activity of the ACC, mPFC, or other areas within the DMN. Accordingly, we tested whether plasma interleukin (IL)-6, an indicator of systemic inflammation, covaried with resting-state functional connectivity of the DMN among 98 adults aged 30-54 (39% male; 81% Caucasian). Independent component analyses were applied to resting state fMRI data to generate DMN connectivity maps. Voxel-wise regression analyses were then used to test for associations between IL-6 and DMN connectivity across individuals, controlling for age, sex, body mass index, and fMRI signal motion. Within the DMN, IL-6 covaried positively with connectivity of the sub-genual ACC and negatively with a region of the dorsal medial PFC at corrected statistical thresholds. These novel findings offer evidence for a unique association between a marker of systemic inflammation (IL-6) and ACC and mPFC functional connectivity within the DMN, a network that may be important for linking aspects of immune function to psychological and behavioral states in health and disease.
默认模式网络（DMN）包含在休息时表现出一致神经活动的大脑系统。DMN 大脑系统与各种社会、认知和情感过程有关，也与与系统性炎症相关的痴呆症和精神障碍形式的风险有关。DMN 内的前扣带皮层（ACC）和周围的内侧前额叶皮层（mPFC）区域特别涉及调节自主和神经内分泌过程，这些过程通过双向信号机制与系统性炎症有关。然而，炎症的指标是否直接与 ACC、mPFC 或 DMN 内的其他区域的静息状态活动相关，这仍然不清楚。因此，我们测试了血浆白细胞介素（IL）-6 是否与 98 名年龄在 30-54 岁的成年人（39%为男性；81%为白种人）的 DMN 静息状态功能连接相关。独立成分分析应用于静息状态 fMRI 数据以生成 DMN 连接图。然后，使用体素回归分析来测试个体之间 IL-6 和 DMN 连接之间的关联，控制年龄、性别、体重指数和 fMRI 信号运动。在 DMN 中，IL-6 与 sub-genual ACC 的连接呈正相关，与背内侧 PFC 的一个区域的连接呈负相关，在纠正后的统计阈值下。这些新发现为系统性炎症标志物（IL-6）与 DMN 内的 ACC 和 mPFC 功能连接之间的独特关联提供了证据，该网络可能对于将免疫功能的各个方面与健康和疾病中的心理和行为状态联系起来很重要。
