Early Chronic Stress and Development of Depression: Mechanisms of Risk

描述(由申请人提供)：经历慢性应激生活事件是抑郁症发展的最受支持的风险因素之一；然而，人们对早期慢性应激与抑郁症的认知和生理机制知之甚少。先前的研究表明，长期应激的青少年在处于悲伤情绪时会表现出对悲伤刺激的高度关注(即有偏见的注意)，这可能会加剧情绪体验，并增强对急性应激源的生理反应。抑郁症领域的研究表明，抑郁的人也表现出对悲伤刺激的高度关注，并经常对负面刺激或沉思进行持之以恒的关注。此外，这些人表现出从急性应激源中恢复的生理受损。到目前为止，这些研究的多个领域之间缺乏整合。目前尚不清楚一个人是如何从情绪相关的偏向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，高强度或持之以恒的注意力是否有助于生理唤醒以及随后的生理反应和恢复。这项拟议的研究是一组新颖的研究，旨在探索早期慢性压力可能导致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。具体地说，这项研究的目的是：1)确定长期应激青少年是否在悲伤情绪中对悲伤刺激表现出即时和长期的注意偏差，长期的注意偏差是否与沉思有关，以及注意力偏差是否与高度的生理唤醒有关；2)测试信息处理异常是否会对生理反应和恢复过程产生因果影响；3)长期应激的青少年如果表现出即时和长期的注意偏差，预期是否会增加患抑郁症的风险。我们将使用与任务无关的情绪面孔刺激的注意任务，并测量长期应激和控制青少年对不同情绪刺激的不同反应时，作为一种偏向注意的测量。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。 公共卫生相关性：抑郁症是世界范围内导致残疾的主要原因，大约20%的人口会在一生中的某个时候经历抑郁发作。风险因素和风险机制的隔离为制定有效的早期干预措施奠定了基础，这些干预措施可以在个人出现抑郁症之前实施，以有效地减轻疾病的个人、经济和社会负担。

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.