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通常注入了一种情感相关性，这种相关性在传统的衰老记忆研究中是不存在的，甚至可能被避免。迄今为止，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群体的情绪记忆的单一研究中调查行为、大脑结构和大脑生理学。为了填补这一空白，我们将采取双管齐下的方法：一系列的行为实验，这些实验将显示情绪效价在多大程度上对老年人记忆信息的数量和质量有好处；并采用先进的结构和功能磁共振成像技术进行相关实验。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，情绪刺激的记忆力通常更好。来自我们实验室和其他实验室的证据表明，老年人也表现出基于情绪效价的增强。然而，尚不清楚正常的衰老是否会影响支持情绪增强的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。这个问题特别有趣，因为老年人很难回忆起非情感事件的具体细节（与记住事件的要点相比）。对中性事物的回忆记忆被认为依赖于海马体的形成，我们预测对情绪刺激的回忆增强是由杏仁核、其他内侧颞叶结构和前额皮质之间的联系产生的。与老年人根据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消极情境中的中性刺激和嵌入在中性情境中的中性刺激没有表现出增强。该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，以及这种损伤是否与特定大脑区域的功能障碍有关。由于前额叶皮层在将一个项目与其背景或源记忆联系起来方面的特殊作用，我们提出老年人的增强减弱可能是由于前额叶皮层的结构或功能改变。

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.