Reducing Rumination in Depression: Mechanisms and Effects

 描述（由申请人提供）：重度抑郁症（MDD）是所有精神疾病中最普遍和最具破坏性的疾病之一，也是全球最沉重的疾病。因此，我们必须确定和检查的影响，改变机制参与维护MDD。在这种情况下，研究人员已经证明，难以从工作记忆中删除负面信息是MDD的核心认知特征。重要的是，这种认知困难与抑郁症状和沉思的持续存在有关，沉思是一种阻碍从压力中恢复并加剧负面影响的思维方式。到目前为止，研究联系起来的困难，从工作记忆中删除负面信息与反刍，持续的负面影响，并在MDD的压力恢复有限的使用相关的方法。重要的是，认知偏差修正（CBM）文献强调了操纵认知过程的可行性，以测试因果关系，并确定参与疾病的发作和维持的机制。因此，本研究的一个主要目的是建立在已建立的CBM方法的基础上，以提高抑郁个体从工作记忆中去除负面信息的能力。我们建议检查RNI训练的认知，情感和生物学效应（目的1）。此外，我们还建议研究RNI训练（目标2）有益效果的神经机制。为了实现这些目标，50名被诊断患有MDD的参与者将被分配接受真实的或假RNI培训。所有参与者将完成培训前基于实验室的和神经影像学课程，六个在家真实的或假RNI培训课程，培训后基于实验室的和神经影像学课程，以及三个月的随访评估。我们预计，与Sham RNI训练相比，真实的RNI训练将a）提高抑郁参与者从训练前到训练后从工作记忆中去除负面信息的能力; B）降低反刍和抑郁症状的水平;以及c）改善随后的情绪和生物压力恢复。我们进一步预期，RNI训练将通过减少从训练前到训练后对认知努力有益的区域（背侧前扣带回、后顶叶和岛叶皮层）的大脑激活，以及减少位于反刍之下的区域（膝下前扣带回皮层和内侧前额叶皮层）的功能连接来实现其有益效果。本研究的结果将增加我们对工作记忆，反刍和抑郁症状的偏见之间的关系的理解，并将有助于识别和阐明特定的机制，有助于MDD的发病和维持。

 DESCRIPTION (provided by applicant): Major Depressive Disorder (MDD) is among the most prevalent and devastating of all psychiatric disorders, and is the single most burdensome disease worldwide. Consequently, it is imperative that we identify and examine the effects of altering mechanisms involved in the maintenance of MDD. In this context, investigators have documented that difficulty removing negative information from working memory is a core cognitive feature of MDD. Importantly, this cognitive difficulty is implicated in the persistence o both depressive symptoms and rumination, a style of thinking that hinders recovery from stress and exacerbates negative affect. To date, research linking difficulty removing negative information from working memory with rumination, the persistence of negative affect, and stress recovery in MDD has been limited by the use of correlational methodologies. Importantly, the Cognitive Bias Modification (CBM) literature underscores the viability of manipulating cognitive processes both to test causal relations and to identify mechanisms involved in the onset and maintenance of disorders. Therefore, a major aim of the proposed study is to build on established CBM methods to improve depressed individuals' ability to remove negative information (RNI) from working memory. We propose to examine the cognitive, affective, and biological effects of RNI training (Aim 1). In addition, we also propose to examine the neural mechanisms that underlie the beneficial effects of RNI training (Aim 2). To achieve these aims, 50 participants diagnosed with MDD will be assigned to receive either Real or Sham RNI training. All participants will complete pre-training laboratory-based and neuroimaging sessions, six at-home Real or Sham RNI training sessions, post-training laboratory-based and neuroimaging sessions, and a three-month follow-up assessment. We expect that, compared to Sham RNI training, Real RNI training will a) improve depressed participants' ability to remove negative information from working memory from pre- to post-training; b) decrease levels of rumination and depressive symptoms; and c) improve subsequent emotional and biological stress recovery. We further expect that RNI training will achieve its beneficial effects by decreasing brain activation from pre- to post-training in regions that subserve cognitive effort (dorsal anterior cingulate, posterior parietal lobe, and insular cortex), and by decreasing functional connectivity in regions posited to underlie rumination (subgenual anterior cingulate cortex and medial prefrontal cortex). The results of this study will increase our understanding of the relations among biases in working memory, rumination, and depressive symptoms, and will help to identify and elucidate specific mechanisms that contribute to the onset and maintenance of MDD.