Emotional Memory in Aging: Cognitive & Neural Processes

描述(由申请人提供)：日常生活的材料和记忆经常被注入一种情感相关性，这在传统的关于衰老记忆的研究中是不存在的，甚至可能被避免。到目前为止，很少有研究调查老年人情绪记忆的认知和神经基础，也没有人在任何参与者组的单个情绪记忆研究中调查行为、大脑结构和脑生理。为了填补这一空白，我们将采取双管齐下的方法：一系列行为实验，将展示情绪价值在多大程度上对老年人记忆的信息的数量和质量产生好处；以及相关的使用先进技术的结构和功能磁共振成像实验。这些研究将使我们能够揭示年轻人情绪记忆的神经结构，以及老年人情绪记忆回路的改变和保存。在年轻人中，与中性刺激相比，情绪性刺激的记忆通常更好。来自我们实验室和其他人的证据表明，老年人也表现出基于情感价值的增强。然而，目前尚不清楚正常衰老是否会影响支持情绪增强的一个特定组成部分的认知或神经机制：记忆负面事件丰富细节的能力增强。这个问题特别令人感兴趣，因为老年人很难回忆起非情绪化事件的具体细节(与记住事件的主旨相比)。对中性项目的记忆记忆被认为依赖于海马体结构，我们预测对情绪刺激的记忆增强来自杏仁核、其他内侧颞叶结构和前额叶皮质之间的联系。与老年人基于物品的唤醒或效价表现出增强的能力相反，我们发现老年人对嵌入在负面与中性背景中的中性刺激没有表现出增强。这项拟议研究的第二个目标是检查这种缺陷是否存在于一系列刺激中，以及这种损害是否与特定大脑区域的功能障碍有关。由于前额叶皮质在将项目与其背景或源记忆绑定方面的特殊作用，我们认为老年人的增强减少可能是由于前额叶皮质的结构或功能改变。

DESCRIPTION (provided by applicant): The material and memories of everyday life are often infused with an emotional relevance that is not present, and may even be avoided, in traditional studies of memory in aging. To date, few studies have investigated the cognitive and neural substrates of emotional memory in older adults, and none has investigated behavior, brain structure, and brain physiology in a single study of emotional memory in any participant group. To fill this gap, we will adopt a two-pronged approach: a series of behavioral experiments that will show the extent to which emotional valence conveys a benefit on the quantity and, significantly, the quality of information remembered by older adults; and related structural and functional magnetic resonance imaging experiments using advanced technology. These investigations will allow us to uncover the neural structures that underlie emotional memory in younger adults, and altered and preserved emotional memory circuits in older adults. In young adults, memory is typically better for emotional as compared to neutral stimuli. Evidence from our laboratory and others suggests that older adults also show enhancement based on emotional valence. It is unclear, however, whether normal aging affects the cognitive or neural mechanisms supporting a specific component of emotional enhancement: the increased ability to remember rich details of a negative event. This question is of particular interest because older adults have difficulty recalling specific details of non-emotional events (as compared to remembering the gist of the events). Recollective memory for neutral items is thought to rely on the hippocampal formation, and we predict that the recollective enhancement for emotional stimuli results from connections between the amygdala, other medial temporal lobe structures, and prefrontal cortex. In contrast to older adults' ability to show enhancement based on the arousal or valence of an item, we found that older adults do not show enhancement for neutral stimuli embedded in a negative versus a neutral context. A second goal of the proposed research is to examine whether this deficit is present across a range of stimuli, and whether the impairment is related to dysfunction of specific brain regions. Because of the particular role of prefrontal cortex in binding an item to its context, or source memory, we propose that older adults' reduced enhancement may be due to structural or functional alterations in prefrontal cortex.