Department of Psychiatry, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
Psychiatry Res. 2011 Sep 30;193(3):144-50. doi: 10.1016/j.pscychresns.2011.01.012. Epub 2011 Jul 20.
Most functional neuroimaging studies of major depressive disorder (MDD) employ univariate methods of statistical analysis to localize abnormalities of neural activity. Less has been done to investigate functional relations between these regions, or with regions not usually implicated in depression. Examination of intraneuronal and interneural network relations is important for the advancement of emerging network models for MDD. Principal component analysis (PCA), a multivariate statistical method, was used to examine differences in functional connectivity between 10 unmedicated patients with MDD and 12 healthy subjects engaged in a positive word viewing task. In healthy subjects, principal component (PC) 1 (33% variance) revealed functional connectivity of task-specific sensory, linguistic, and motor regions, along with functional anticorrelations in the default mode network; PC2 (10% variance) displayed functional connectivity of areas involved in emotional processing. This segregation of functions did not occur in the depressed group, where regions involved in emotional functions appeared in PC1 (34% variance) co-varying with those involved in linguistic, motor, and default mode network processing. The lack of segregation of emotional processing from cognitive and sensorimotor functions may represent a systems level neural substrate for a core phenomenon of depression: the interconnection of affective disturbance with experience, cognition, and behavior.
大多数重度抑郁症(MDD)的功能性神经影像学研究采用单变量统计分析方法来定位神经活动的异常。对于这些区域之间的功能关系,或者与通常与抑郁症无关的区域之间的功能关系,研究得较少。研究神经元内和神经元间网络关系对于推进 MDD 的新兴网络模型很重要。主成分分析(PCA)是一种多变量统计方法,用于检查 10 名未经药物治疗的 MDD 患者和 12 名参与积极单词观看任务的健康受试者之间功能连接的差异。在健康受试者中,主成分(PC)1(33%的方差)揭示了特定于任务的感觉、语言和运动区域的功能连接,以及默认模式网络中的功能负相关;PC2(10%的方差)显示了涉及情绪处理的区域的功能连接。这种功能的分离在抑郁组中没有发生,在抑郁组中,涉及情绪功能的区域出现在 PC1 中(34%的方差),与涉及语言、运动和默认模式网络处理的区域共同变化。情绪处理与认知和感觉运动功能的分离缺失可能代表了抑郁症的一个核心现象的系统水平神经基质:情感障碍与经验、认知和行为的相互联系。