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的不利身体和情感健康结果联系起来。最近，研究发现与压力相关的变量是认知老化的重要预测因素。然而，无论是在个体内部还是在个体之间，压力的负面影响都有相当大的变异性。不同的压力源的特性导致了这种差异，但暴露在相同或相似压力源下的个体在反应上仍然表现出显著的差异。理解这种变异性的机制对于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来说是一个关键的挑战。一个人反复思考和在精神上“重温”有问题的情况和事件的倾向会放大和延伸情绪和生理反应，即使在引发压力的因素停止后也是如此。我们假设，这种包含担忧和沉思等概念的非建设性重复思维(URT)是压力源对认知健康产生有害影响的最终心理途径。我们建议通过对城市轨道交通进行纵向研究来检验这一假设，将其作为压力(当前和累积)对认知功能影响的潜在中介。由于认知老化的早期指标早在老年之前就显现出来，因此拟议的样本将包括320个不同种族的人，他们处于成年早期和中年(年龄在25-65岁之间)。我们的设计将是一个“测量突发”，包括8个两年一次的“突发”，每天评估14个认知、压力、URT、情感和生理标记物。这种设计将允许在从几天到几年的时间范围内对这些变量之间的超前-滞后关系进行建模。这项研究将针对四个目标：目标1和目标2考察城市轨道交通在解释短期(每日)和中期(两年)应激对个体认知变异性和变化的影响中的作用。目标3和4将城市轨道交通作为压力对长期(跨年)认知变化的累积影响的中介。这项研究的意义在于：1)加深了对成年早期和中年压力如何影响认知老化风险的理解；2)确定了将压力体验与认知老化联系起来的机制(URT)；3)解决了关于压力、HPA轴功能和认知的时间进程的不一致；以及4)确定了压力和认知变化的时间顺序。概念和方法创新的领域包括：(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，对一系列心理和身体健康结果具有重要影响；(2)使用测量突发设计，通过检查从天到年的不同时间尺度的超前-滞后关系来评估中介假设；以及(3)使用分析方法来检验培训个人和培训个人认知变化的各个方面。 公共健康相关性：拟议研究的影响来自于提高我们对环境、心理和生理压力相关的影响如何累积到影响认知健康的理解。通过确定有针对性的干预机制，这项研究的知识将直接为促进老年人认知健康的预防策略提供信息。

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.