Key Laboratory of Biomedical Information Engineering of the Ministry of Education, Institute of Biomedical Engineering, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China; National Engineering Research Center of Health Care and Medical Devices, Xi'an Jiaotong University Branch, Xi'an 710049, China.
Department of Radiology, the Affiliated Xi'an Central Hospital of Xi'an Jiaotong University, Xi'an 710003, China.
J Affect Disord. 2018 Feb;227:280-288. doi: 10.1016/j.jad.2017.11.018. Epub 2017 Nov 7.
Major depressive disorder (MDD) is a mental disorder characterized by cognitive and affective deficits. Previous studies suggested that insula is a crucial node of the salience network for initiating network switching, and dysfunctional connection to this region may be related to the mechanism of MDD. In this study, we systematically investigated and quantified the altered functional connectivity (FC) of the specific insular subdivisions and its relationship to psychopathology of MDD.
Resting-state FC of insular subdivisions, including bilateral ventral/dorsal anterior insula and posterior insula, were estimated in 19 MDD patients and 19 healthy controls. Abnormal FC was quantified between groups. Additionally, we investigated the relationships between insular connectivity and depressive symptom severity.
MDD patients demonstrated aberrant FC for insular subdivisions to superior temporal sulcus, inferior prefrontal gyrus, amygdala and posterior parietal cortex. Moreover, depression symptoms (Hamilton Depression Rating Scale and Hamilton Anxiety Rating Scale scorers) were associated with the FC values of insular subdivisions.
First, the sample size of our current study is relatively small, which may affect the statistic power. Second, using standardized insular subdivision seeds for FC analyses may neglect subtle natural differences in size and location of functional area across individuals and may thus affect connectivity maps.
Abnormal FC of insular subdivisions to default network and central executive network may represent impaired intrinsic networks switching which may affect the underlying emotional and sensory disturbances in MDD. And our findings can help to understand the pathophysiology and underlying neural mechanisms of MDD.
重度抑郁症（MDD）是一种以认知和情感缺陷为特征的精神障碍。先前的研究表明，脑岛是启动网络切换的突显网络的关键节点，而与该区域的功能连接障碍可能与 MDD 的机制有关。在这项研究中，我们系统地研究和量化了特定脑岛亚区的改变功能连接（FC）及其与 MDD 精神病理学的关系。
在 19 名 MDD 患者和 19 名健康对照者中，估计了脑岛亚区（包括双侧腹/背前脑岛和后脑岛）的静息状态 FC。在组间量化异常 FC。此外，我们还研究了脑岛连接与抑郁症状严重程度之间的关系。
MDD 患者的脑岛亚区与上颞回、下前额叶回、杏仁核和后顶叶皮质之间存在异常 FC。此外，抑郁症状（汉密尔顿抑郁评定量表和汉密尔顿焦虑评定量表评分者）与脑岛亚区的 FC 值相关。
首先，我们当前研究的样本量相对较小，这可能会影响统计能力。其次，使用标准化的脑岛亚区种子进行 FC 分析可能会忽略个体之间功能区大小和位置的细微自然差异，从而影响连接图。
脑岛亚区与默认网络和中央执行网络的异常 FC 可能代表内在网络切换受损，这可能会影响 MDD 中的潜在情绪和感觉障碍。我们的发现有助于理解 MDD 的病理生理学和潜在的神经机制。
