Early Chronic Stress and Development of Depression: Mechanisms of Risk

描述（由申请人提供）：长期压力生活事件的经历是抑郁症发展的最受支持的风险因素之一；然而，人们对早期慢性压力和抑郁之间的认知和生理机制知之甚少。先前的研究表明，长期压力的青少年在悲伤情绪中表现出对悲伤刺激的高度关注（即，有偏见的注意），而悲伤情绪可能会加强情绪体验，并且对急性压力源的生理反应会增强。在抑郁症领域的研究表明，抑郁症患者对悲伤的刺激也表现出高度的关注，并且经常对消极的刺激进行持续的关注，或者沉思。此外，这些个体从急性应激源中表现出受损的生理恢复。迄今为止，这些多领域的研究之间缺乏整合。目前还不清楚一个人是如何从情绪相关的偏见注意力和压力反应发展到长期的、强烈的抑郁情绪体验的。同样未被探索的是，增强或持续的注意力是否有助于生理唤醒和随后的生理反应和恢复。提出的研究是一套新颖的研究，探索早期慢性压力可能带来抑郁风险的认知和生理后果，并测试这些领域之间相互作用的确切性质。具体而言，本研究的目的是：1)确定慢性压力青少年是否在悲伤情绪下对悲伤刺激表现出即时和长期的注意偏向，是否长期的注意偏向与反刍有关，以及注意偏向是否与生理唤醒有关；2)测试信息处理异常是否对生理反应性和恢复过程产生因果影响。3)表现出即时和长期注意偏差的慢性压力青少年是否具有更高的抑郁风险。我们将使用具有任务无关情绪面孔刺激的注意任务，测量慢性应激和对照青少年对不同情绪刺激的差异反应时间，作为偏注意的测量。我们将使用血压监测仪和皮质醇测量来评估生理反应和恢复情况。

DESCRIPTION (provided by applicant): Experience of a chronic stressful life event is one of the most supported risk factors for development of depression; however, little is known about the cognitive and physiological mechanisms linking early chronic stress and depression. Previous research has shown that chronically stressed adolescents show heightened attention to sad stimuli (i.e., biased attention) while in a sad mood that may intensify the mood experience, and heightened physiological reactivity to acute stressors. Work in field of depression suggests that depressed individuals also show heightened attention to sad stimuli, and frequently engage in perseverative attention to negative stimuli, or rumination. Additionally, these individuals show impaired physiological recovery from acute stressors. To date, integration among these multiple domains of research is lacking. It remains unclear how an individual progresses from mood-related biased attention and stress reactivity to the prolonged, intense mood experience of depression. Also unexplored is whether heightened or perseverative attention contribute to physiological arousal and subsequent physiological reactivity and recovery. The proposed research is a novel set of studies exploring the cognitive and physiological consequences of early chronic stress that may confer risk for depression, and testing the precise nature of the interaction between these domains. Specifically, the aims of the research are 1) to determine if chronically stressed adolescents show immediate and prolonged attention biases to sad stimuli in a sad mood, whether prolonged attention bias is related to rumination, and whether attention biases are related to heightened physiological arousal, 2) to test whether information processing anomalies causally influence physiological reactivity and recovery processes, and 3) whether chronically stressed adolescents who show immediate and prolonged attention biases are at heightened risk for depression prospectively. We will use an attention task with task- irrelevant emotional face stimuli and measure differential reaction times of chronically stressed and control adolescents for different emotional stimuli as a measure of biased attention. We will use blood pressure monitors and cortisol measurements to assess physiological reactivity and recovery. PUBLIC HEALTH RELEVANCE: Depressive disorders are the leading cause of disability worldwide, and approximately 20% of the population will experience a depressive episode at some point in their life. Isolation of risk factors and mechanisms of risk lays the groundwork for development of effective early interventions that can be implemented before an individual develops depression, to effectively reduce the personal, economic, and social burden of the illness.