Carolina Institute for Developmental Disabilities, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27599-7160, USA.
BMC Psychiatry. 2012 Sep 21;12:152. doi: 10.1186/1471-244X-12-152.
Studies of individuals who do not meet criteria for major depressive disorder (MDD) but with subclinical levels of depressive symptoms may aid in the identification of neurofunctional abnormalities that possibly precede and predict the development of MDD. The purpose of this study was to evaluate relations between subclinical levels of depressive symptoms and neural activation patterns during tasks previously shown to differentiate individuals with and without MDD.
Functional magnetic resonance imaging (fMRI) was used to assess neural activations during active emotion regulation, a resting state scan, and reward processing. Participants were twelve females with a range of depressive symptoms who did not meet criteria for MDD.
Increased depressive symptom severity predicted (1) decreased left midfrontal gyrus activation during reappraisal of sad stimuli; (2) increased right midfrontal gyrus activation during distraction from sad stimuli; (3) increased functional connectivity between a precuneus seed region and left orbitofrontal cortex during a resting state scan; and (4) increased paracingulate activation during non-win outcomes during a reward-processing task.
These pilot data shed light on relations between subclinical levels of depressive symptoms in the absence of a formal MDD diagnosis and neural activation patterns. Future studies will be needed to test the utility of these activation patterns for predicting MDD onset in at-risk samples.
研究那些不符合重性抑郁障碍（MDD）标准但存在亚临床抑郁症状的个体，可能有助于识别神经功能异常，这些异常可能先于并预测 MDD 的发生。本研究的目的是评估亚临床抑郁症状水平与先前用于区分 MDD 患者和非 MDD 患者的任务期间的神经激活模式之间的关系。
使用功能磁共振成像（fMRI）评估在积极情绪调节、静息状态扫描和奖励处理期间的神经激活。参与者为 12 名女性，抑郁症状程度不一，但不符合 MDD 标准。
抑郁症状严重程度的增加预测了（1）在重新评估悲伤刺激时左额中回激活的减少；（2）在从悲伤刺激中分心时右额中回激活的增加；（3）在静息状态扫描期间，楔前叶种子区域和左眶额皮层之间的功能连接增加；（4）在奖励处理任务中，非赢得出现时，扣带回激活增加。
这些初步数据揭示了在没有正式 MDD 诊断的情况下，亚临床抑郁症状水平与神经激活模式之间的关系。未来的研究将需要测试这些激活模式在预测高危样本中 MDD 发病的效用。
