Task-specific and person-specific factors related to Subjective Cognitive Decline

在认知老化领域，迫切需要确定临床前的标志物， 阿尔茨海默病（AD），以便在疾病早期进行药物干预 频谱的时间，当它可以是最有效的。越来越多的人对主观 认知能力下降（SCD）作为临床前AD的潜在标志物。SCD，或者说 一个人的认知能力下降，尽管在标准诊断测试中表现“正常”， 重要的健康结果，是有关许多老年人，并导致一些人寻求 医疗护理。确定SCD可作为临床前标志物的程度 AD具有很大的价值，因为SCD是非侵入性的，便宜的，并且容易获得。然而，在这方面， SCD是一个复杂的多因素结构。为了确定它作为一种标志物的真正效用， 在临床前AD中，全面表征影响SCD的因素至关重要， 影响SCD反映“真实”或实际认知功能的程度。事实上，SCD 不仅反映了一个人的实际认知功能，而且还反映了特定任务的因素 (i.e.,如何测量SCD）和个人特定因素（例如，一个人有多擅长自我- 评价;一个人感觉自己有多老;一个人对衰老的看法）。本次纵向调查的目标 建议是检查新的任务特定和个人特定的因素，可能会 影响SCD和/或其与200名老年人实际（客观测量）认知的相关性 成年人了拟议研究的一个关键方面是包括敏感，客观的认知 结果，这将使一个更精确的检查之间的关联SCD和 比迄今为止所进行的客观认知。第一个客观认知结果是 视觉短期记忆（STM）绑定任务的表现是高度敏感的 并且当标准神经心理学测试在正常限度内时，特异于AD病理学。 我们还将研究注意力控制，作为衡量非记忆变化的一种手段， 在某些个体中，记忆变化之前的早期AD是明显的。最后一个关键成果是 随着时间的推移，认知变化，使检查可能发生的认知微妙下降 当个体在横截面测试中仍在正常范围内时。采取 总之，这些目标体现了SCD工作组（2014年）最近确定的关键问题 作为推进SCD知识的当前状态的关键，并将有助于一个新的 SCD模型拟议研究的结果将为如何 评估和解释老年人的SCD，并将为确定如何以及何时 SCD可用作临床前阿尔茨海默病的指标。

In the field of cognitive aging, there is an urgent push to identify the markers of pre-clinical Alzheimer’s disease (AD) in order to move pharmacologic intervention earlier in the disease spectrum to a time when it can be most effective. There is growing interest in subjective cognitive decline (SCD) as a potential marker of pre-clinical AD. SCD, or the perception that one’s cognition has declined despite “normal” performance on standard diagnostic testing, is an important health outcome that is concerning to many older adults, and leads some to seek medical attention. Determining the extent to which SCD may serve as a pre-clinical marker of AD is of great value, as SCD is non-invasive, inexpensive, and easily obtainable. However, SCD is a complex, multi-factorial construct. In order to determine its true utility as a marker of pre-clinical AD, it is critical to comprehensively characterize the factors that influence SCD, and that affect the degree to which SCD reflects “true” or actual cognitive functioning. Indeed, SCD is certain to reflect not only a person’s actual cognitive functioning, but also task-specific factors (i.e., how SCD is measured) and person-specific factors (e.g., how good one is at self- evaluation; how old one feels; what one believes about aging). The goals of this longitudinal proposal are to examine novel task-specific and person-specific factors that are likely to influence SCD and/or its association with actual (objectively measured) cognition in 200 older adults. A key aspect of the proposed study is the inclusion of sensitive, objective cognitive outcomes that will enable a more precise examination of the association between SCD and objective cognition than has been conducted thus far. The first objective cognitive outcome is performance on a visual short term memory (STM) binding task shown to be highly sensitive and specific to AD pathology when standard neuropsychological testing is within normal limits. We will also examine attentional control as a measure of non-memory changes that may signal early AD before memory changes are apparent in some individuals. A final critical outcome is cognitive change over time, enabling examination of subtle decline in cognition that may occur when individuals still perform within the normal range on cross-sectional testing. Taken together, these aims embody key issues recently identified by the SCD Working Group (2014) as critical for advancing the current state of knowledge on SCD, and will contribute to a novel model of SCD. Results from the proposed study will provide specific guidelines for how to assess and interpret SCD in older adults, and will set the stage for determining how and when SCD may be used as an indicator of preclinical Alzheimer’s disease.