ERP Investigations of Novelty Processing in Different Patterns of Cognitive Aging

描述(由申请人提供)：随着越来越多的美国人活到高龄，了解是什么让个人保持有意义的智力功能和独立性已经成为一个主要的公共卫生问题。这项研究的主要目的是调查认知成功的老年人与认知不太成功的老年人在信息加工方面的不同之处。将测量感觉-知觉编码、选择性注意和容量受限控制加工的事件相关电位(ERP)指数。这将提供一个机会来评估关于认知老化的相互竞争的理论，这些理论的不同之处在于，假设哪些信息处理操作对年龄相关的认知变化最重要。我们的建议强调对新奇事物的处理，因为对新奇事物的反应增强可能不仅反映了认知老化的成功，而且有助于促进认知老化。在这项拟议的研究中，根据与年龄相适应的神经心理测试标准，18岁至90岁以上的人将被分为认知能力较高的人和认知能力一般的人。一套精心设计的ERP实验将考察在以下条件下认知状态不同的群体在新奇加工中年龄相关变化的程度：1)能力受限的受控加工(目标1)，2)与背景相适应的资源分配(目标2)，以及3)选择性注意与任务相关的事件(目标3)。目标1将通过比较在单任务和双任务条件下对新刺激的反应来实现。目标2将通过比较在不同条件下对新奇事物的反应来解决，这些条件不同，无论新的刺激是分心的还是潜在的有意义的事件。目标3将通过比较注意和忽略条件下对显著刺激的反应来实现。我们的工作将为以下方面提供重要的见解：1)认知能力较高的成年人和表现一般的成年人之间的年龄相关差异在多大程度上是由于一般表演者寿命较早开始的信息处理能力的下降；2)在信息处理的不同阶段，认知能力较高的成年人和表现一般的成年人之间与年龄相关的差异的幅度有多大；3)不同年龄和认知群体的成员对新奇事件的反应根据事件发生的背景而有所不同的程度；4)感觉-知觉编码、选择性注意和容量受限控制加工的事件相关电位指数在多大程度上能够不同地解释与年龄相关的神经心理表现的变化。总之，这项拟议的研究将提供一个机会来阐明成功认知衰老的基本因素，这一努力对这一重要研究领域至关重要。与公共健康相关：这项拟议的研究将调查导致成功认知衰老的因素，随着越来越多的美国人活到高龄，这是一个对公共健康至关重要的话题。我们将研究18岁至90岁以上智力水平不同的人脑波活动的年龄相关变化。我们的目标是确定使人们在整个成年期保持活跃和高功能的潜在机制。

DESCRIPTION (provided by applicant): As increasing numbers of Americans are living to advanced ages, understanding what allows individuals to maintain meaningful levels of intellectual functioning and independence has become a major public health concern. The primary goal of the proposed research is to investigate the ways in which information processing of cognitively `successful' older adults differs from that of cognitively less successful ones. Event-related potential (ERP) indices of sensory-perceptual encoding, selective attention, and capacity- limited controlled processing will be measured. This will provide an opportunity to evaluate competing theories about cognitive aging that differ in terms of which information processing operations are hypothesized to be most important to age-related changes in cognition. Our proposal emphasizes novelty processing because increased responsiveness to novelty may not only be a reflection of successful cognitive aging, but also help to promote it. In the proposed study, individuals from 18 to over 90 years old will be divided into cognitively high and cognitively average performers based on age-appropriate neuropsychological test norms. A carefully planned set of ERP experiments will examine the extent to which groups varying in cognitive status differ in age-related changes in novelty processing under conditions that manipulate demands on 1) capacity-limited controlled processing (Aim 1), 2) context-appropriate resource allocation (Aim 2), and 3) selective attention to task-relevant events (Aim 3). Aim 1 will be addressed by comparing responses to novel stimuli under single vs. dual-task conditions. Aim 2 will be addressed by comparing responses to novelty under conditions that vary whether novel stimuli serve as distracters or potentially meaningful events. Aim 3 will be addressed by comparing responses to salient stimuli under attend vs. ignore conditions. Our work will provide important insights into 1) the extent to which age-related differences between cognitively high and average performing adults are due to a decline in information processing capacity that begins earlier in the lifespan for average performers; 2) the extent to which the magnitude of age-related differences between cognitively high and average performing adults differ across various stages of information processing; 3) the extent to which members of different age and cognitive groups are able to vary their response to novel events depending on the context in which they occur; and 4) the extent to which ERP indices of sensory-perceptual encoding, selective attention, and capacity-limited controlled processing can differentially account for the variance in age-related changes in neuropsychological performance. In summary, the proposed research will provide an opportunity to elucidate factors that are fundamental to successful cognitive aging, an endeavor that is critical to this important field of study. PUBLIC HEALTH RELEVANCE: The proposed research will investigate factors that contribute to successful cognitive aging, a topic of major importance to public health as an increasing number of Americans are living to advanced ages. We will study age-related changes in brain wave activity in individuals from 18 to over 90 years old who vary in their level of intellectual functioning. We aim to identify underlying mechanisms that allow people to remain active and high functioning throughout adulthood.