LIAMA Center for Computational Medicine, National Laboratory of Pattern Recognition, Institute of Automation, Chinese Academy of Sciences, Beijing, China.
PLoS One. 2012;7(5):e37561. doi: 10.1371/journal.pone.0037561. Epub 2012 May 30.
Increasing evidence indicates that major depressive disorder (MDD) is usually accompanied by altered white matter in the prefrontal cortex, the parietal lobe and the limbic system. As a behavioral abnormity of MDD, rumination has been believed to be a substantial indicator of the mental state of the depressive state. So far, however, no report that we are aware of has evaluated the relationship between white matter alterations and the ruminative state. In this study, we first explored the altered white matter using a tract-based spatial statistics (TBSS) method based on diffusion tensor imaging of 19 healthy and 16 depressive subjects. We then investigated correlations between the altered white matter microstructure in the identified altered regions and the severity of ruminations measured by the ruminative response scale. Our results demonstrated altered white matter microstructure in circuits connecting the prefrontal lobe, the parietal lobe and the limbic system (p<0.005, uncorrected), findings which support previous research. More importantly, the result also indicated that a greater alteration in the white matter is associated with a more ruminative state (p<0.05, Bonferroni corrected). The detected abnormalities in the white matter should be interpreted cautiously because of the small sample size in this study. This finding supports the psychometric significance of white matter deficits in MDD.
越来越多的证据表明，重度抑郁症（MDD）通常伴随着前额叶皮质、顶叶和边缘系统的白质改变。作为 MDD 的一种行为异常，反刍被认为是抑郁状态精神状态的重要指标。然而，到目前为止，我们没有注意到有任何报告评估了白质改变与反刍状态之间的关系。在这项研究中，我们首先使用基于扩散张量成像的束路径空间统计学（TBSS）方法，对 19 名健康受试者和 16 名抑郁受试者的大脑进行了分析，以探索白质的改变。然后，我们研究了在确定的改变区域中，白质微观结构的改变与反刍反应量表测量的反刍严重程度之间的相关性。我们的结果表明，连接前额叶、顶叶和边缘系统的回路中的白质微观结构发生了改变（p<0.005，未校正），这一结果支持了之前的研究。更重要的是，结果还表明，白质的更大改变与更严重的反刍状态相关（p<0.05，Bonferroni 校正）。由于本研究的样本量较小，因此应该谨慎解释白质异常。这一发现支持了 MDD 中白质缺陷的心理测量学意义。
