Davey Christopher G, Yücel Murat, Allen Nicholas B, Harrison Ben J
Orygen Youth Health Research Centre, The University of Melbourne Melbourne, VIC, Australia.
Front Psychiatry. 2012 Feb 28;3:14. doi: 10.3389/fpsyt.2012.00014. eCollection 2012.
Major depressive disorder is associated with functional alterations in activity and resting-state connectivity of the extended medial frontal network. In this study we aimed to examine how task-related medial network activity and connectivity were affected in depression.
18 patients with major depressive disorder, aged 15- to 24-years-old, were matched with 19 healthy control participants. We characterized task-related activations and deactivations while participants engaged with an executive-control task (the multi-source interference task, MSIT). We used a psycho-physiological interactions approach to examine functional connectivity changes with subgenual anterior cingulate cortex. Voxel-wise statistical maps for each analysis were compared between the patient and control groups.
There were no differences between groups in their behavioral performances on the MSIT task, and nor in patterns of activation and deactivation. Assessment of functional connectivity with the subgenual cingulate showed that depressed patients did not demonstrate the same reduction in functional connectivity with the ventral striatum during task performance, but that they showed greater reduction in functional connectivity with adjacent ventromedial frontal cortex. The magnitude of this latter connectivity change predicted the relative activation of task-relevant executive-control regions in depressed patients.
The study reinforces the importance of the subgenual cingulate cortex for depression, and demonstrates how dysfunctional connectivity with ventral brain regions might influence executive-attentional processes.
重度抑郁症与扩展内侧额叶网络的活动及静息态连接的功能改变有关。在本研究中，我们旨在探究抑郁症患者与任务相关的内侧网络活动及连接是如何受到影响的。
18名年龄在15至24岁之间的重度抑郁症患者与19名健康对照参与者进行匹配。当参与者进行一项执行控制任务（多源干扰任务，MSIT）时，我们对与任务相关的激活和去激活进行了特征描述。我们采用心理生理交互作用方法来检查与膝下前扣带回皮质的功能连接变化。对患者组和对照组之间每次分析的体素水平统计图谱进行比较。
两组在MSIT任务中的行为表现以及激活和去激活模式均无差异。与膝下扣带回的功能连接评估显示，抑郁症患者在任务执行过程中与腹侧纹状体的功能连接没有表现出相同程度的降低，但他们与相邻的腹内侧额叶皮质的功能连接降低幅度更大。后一种连接变化的程度预测了抑郁症患者中与任务相关的执行控制区域的相对激活情况。
该研究强化了膝下扣带回皮质对抑郁症的重要性，并证明了与腹侧脑区的功能连接功能失调可能如何影响执行注意力过程。
