Bae Jae Nam, MacFall James R, Krishnan K Ranga R, Payne Martha E, Steffens David C, Taylor Warren D
Department of Psychiatry, Inha University Hospital, Incheon, South Korea.
Biol Psychiatry. 2006 Dec 15;60(12):1356-63. doi: 10.1016/j.biopsych.2006.03.052. Epub 2006 Jul 28.
The dorsolateral prefrontal cortex (DLPFC) and anterior cingulate cortex (ACC) are critical for mood regulation. Alterations in the white matter connections of these regions may impair their role in mood regulation and increase the risk of developing depression. This study used diffusion tensor imaging to examine for white matter microstructural abnormalities of these regions and of central white matter structures in late-life depression.
One hundred six elderly depressed subjects and eighty-four elderly nondepressed subjects underwent clinical assessment and diffusion tensor imaging. The apparent diffusion coefficient (ADC) and fractional anisotropy (FA) were measured in regions of interest placed in the white matter of the DLPFC, ACC, corpus callosum, and internal capsule. Differences between groups were assessed, controlling for age, sex, and total cerebral volume.
After controlling for covariates, depressed subjects had significantly lower FA values in white matter of the right ACC, bilateral superior frontal gyri, and left middle frontal gyrus. There were no significant differences in ADC values.
Lower FA, representing lower tissue organization, is observed in depressed elders in the DLPFC and right ACC. These findings support the hypothesis that altered connectivity between brain regions contributes to the risk of depression.
背外侧前额叶皮质（DLPFC）和前扣带回皮质（ACC）对情绪调节至关重要。这些区域白质连接的改变可能会损害它们在情绪调节中的作用，并增加患抑郁症的风险。本研究使用扩散张量成像来检查这些区域以及老年抑郁症患者脑白质中心结构的微观结构异常。
106名老年抑郁症患者和84名老年非抑郁症患者接受了临床评估和扩散张量成像。在位于DLPFC、ACC、胼胝体和内囊白质的感兴趣区域测量表观扩散系数（ADC）和分数各向异性（FA）。评估组间差异，并对年龄、性别和全脑体积进行控制。
在控制协变量后，抑郁症患者右侧ACC、双侧额上回和左侧额中回白质的FA值显著降低。ADC值无显著差异。
在DLPFC和右侧ACC的老年抑郁症患者中观察到较低的FA，这代表较低的组织结构。这些发现支持了脑区之间连接改变会增加抑郁症风险这一假说。
