Stress, Unconstructive Repetitive Thought and Cognitive Aging

描述（由申请人提供）：数十年的研究已经将压力与老年人不利的身心健康结果联系起来。最近，研究已经确定了与压力相关的变量是认知衰老的重要预测因素。然而，压力的负面影响在个体内部和个体之间都存在相当大的差异。不同压力源的特征导致了这种差异，但暴露于相同或相似压力源的个体在反应上仍然表现出实质性的差异。理解可以解释这种可变性的机制是解释压力如何影响认知健康以及许多其他与衰老相关的身体和情绪健康结果的关键挑战。一个人倾向于反复思考和在心理上“重温”有问题的情况和事件，这可能会放大和延长情绪和生理反应，即使在引发压力源停止之后也是如此。我们假设，这种非建设性的重复思维（URT），包括担心和沉思等概念，是压力源对认知健康产生有害影响的最终心理途径。我们建议通过纵向调查URT作为压力（当前和累积）对认知功能影响的潜在中介来验证这一假设。由于认知衰老的早期指标早在老年之前就已经显现出来，因此提议的样本将包括320名不同种族的成年早期和中年个体（25-65岁）。我们的设计将是一个“测量爆发”，由8个半年一次的“爆发”组成，包括14个日常评估，包括认知、压力、URT、情感和生理指标。这种设计将允许在从几天到几年的时间尺度上对这些变量之间的领先-滞后关系进行建模。本研究将解决四个目标：目标1和目标2检查URT在解释当前压力对训练个体认知变异性和变化的短期（每日）和中期（半年）的影响方面的作用。目的3和4检验URT作为长期（跨年）认知变化的压力累积效应的中介。本研究的意义在于：1)提高了对成年早期和中年压力如何影响认知衰老风险的认识；2)发现应激体验与认知老化之间的联系机制；3)解决与应激相关的时间过程、下丘脑轴功能和认知的不一致；4)确定压力与认知变化的时间顺序。概念和方法创新领域包括：(1)一个新的理论框架，可以解释急性和慢性应激对认知的影响，对广泛的心理和身体健康结果具有重要意义；(2)利用测量突发设计，通过检验不同时间尺度（从天到年）的超前-滞后关系来评估中介假设；(3)使用分析方法来检查训练中的个体和训练中的个体方面的认知变化。

DESCRIPTION (provided by applicant): Decades of research have linked stress to adverse physical and emotional health outcomes in aging adults. More recently, studies have identified stress-related variables as important predictors of cognitive aging. However, there is considerable variability in the negative effects of stress, both within and across individuals. Characteristics of different stressors contribute to this variation, but individuals exposed to the same or similar stressors still exhibit substantial differences in their responses. Understanding the mechanisms that can account for this variability represents a critical challenge for explaining how stress affects cognitive health as well as many other aging-related physical and emotional health outcomes. A person's tendencies to recurrently think about and mentally 'relive' problematic situations and events can amplify and extend emotional and physiological responses, even after cessation of the eliciting stressor. We hypothesize that such unconstructive repetitive thought (URT), which encompasses concepts such as worry and rumination, operates as a final psychological pathway by which stressors exert their harmful effects on cognitive health. We propose to test this hypothesis by conducting a longitudinal investigation of URT as a potential mediator of the effects of stress (current and cumulative) on cognitive function. Because early indicators of cognitive aging manifest long before old age, the proposed sample will consist of 320 racially diverse individuals in early adulthood and midlife (ages 25-65). Our design will be a 'measurement-burst', consisting of 8 biannual 'bursts' of 14 daily assessments of cognition, stress, URT, affect and physiological markers. This design will allow modeling of lead-lag relationships among these variables across time-scales that range from days to years. This study will address four aims: Aims 1 and 2 examine the role of URT in accounting for the effects of current stress on short-term (daily) and mid-term (biannual) in traindividual cognitive variability and change. Aims 3 and 4 examine URT as a mediator of the cumulative effects of stress on long-term (across years) cognitive change. This significance of this study lies in: 1) improved understanding of how stress in early adulthood and midlife affects risk for cognitive aging; 2) identifying a mechanism (URT) that links the experience of stress to cognitive aging; 3) resolving inconsistencies regarding the time course relating stress, HPA axis function and cognition; and 4) determining the temporal ordering of stress and cognitive change. Areas of conceptual and methodological innovation include: (1) a novel theoretical framework that can explain both acute and chronic stress effects on cognition, with important implications for a broad range of mental and physical health outcomes; (2) use of a measurement burst design to evaluate mediational hypotheses by examining lead-lag relationships across different time scales ranging from days to years; and (3) use of an analytic approach to examine both in train individual and in train individual facets of cognitive change. PUBLIC HEALTH RELEVANCE: The impact of the proposed research derives from improving our understanding of how environmental, psychological and physiological stress-related influences accumulate to affect cognitive health. By identifying a targetable mechanism for interventions, the knowledge from this research will directly inform prevention strategies to promote cognitive health in aging adults.