Memory Representations in Aging

项目摘要/摘要 情节记忆显示出衰老的强劲下降。几十年的神经成像研究已经产生了丰富的 关于与年龄相关的情节记忆下降的神经机制的信息，但 以前的研究是，他们专注于记忆过程(对记忆进行的操作)，而不是 记忆表示法(记忆的内容)。很可能内存表示也会随着 年龄，使得对记忆表征的研究对于提供对机制的新见解至关重要 潜在的与年龄相关的情景记忆下降，这对制定干预措施很重要 记忆力恢复。尤其阻碍了未来的干预发展，目前尚不清楚(1)记忆是如何 表征受到知觉与概念贡献的年龄相关差异的影响 过程，这些过程在整个生命周期内发生变化，并可能成为干预的目标，以及(2)结构如何 内存表示形式的基础在整个生命周期内发生变化，这对于 干预改善与年龄相关的记忆表征缺陷具有长期影响。在这里， 申请人提出了一种创新的双管齐下的方法，检查与年龄相关的差异 知觉与概念加工和脑结构对记忆表征的影响 网络。拟议的项目将在(1)大脑/神经认知评估方面提供指导培训 年轻人和老年人的变化，(2)高级MRI分析(例如，图论，深卷积神经 网络)和(3)多模式成像分析(功能和结构)，这是利用它们所必需的 双管齐下，(4)职业发展。培训计划包括课程作业、研讨会、一个- 一对一辅导，参加研讨会，定向阅读，参加国家和国际会议 会议。在研究1中，在进行功能磁共振成像的同时，36名年轻人和36名老年人研究了 复杂的场景，然后找回他们对场景的记忆。受试者对知觉和概念的使用 这些过程都是经过实验操作的。目标是将与年龄相关的记忆表征质量联系起来 知觉与概念加工中年龄效应的缺陷(目标1)。申请人对此目标进行调查 代表性相似性分析与前沿深度卷积神经网络相结合。在学习中 2、申请人还收集扩散加权图像以链接与年龄相关的记忆表征质量 年龄缺陷对结构脑网络结构的影响(目标2)。申请者用小说研究这一目的 图论和多模式成像(功能和结构)分析。这项调查使用了两个- Pong方法将为年龄相关情节记忆的潜在机制提供一个新的观点 下降，这对干预性发展至关重要。此外，在这一团契达到顶峰时， 申请者将拥有一套专业技能，并为开始下一阶段的培训做好充分准备。

Project Summary/Abstract Episodic memory shows a robust decline in aging. Decades of neuroimaging research has yielded a wealth of information on the neural mechanisms of age-related episodic memory decline, but a particular limitation of previous studies is that they focused on memory processes (operations performed on memories) and not memory representations (the content of memories). It is likely that memory representations also decline with age, making the investigation of memory representations essential to providing novel insight into mechanisms underlying age-related episodic memory decline, which is important for the development of interventions for memory rehabilitation. Particularly hindering future intervention development, it is unclear (1) how memory representations are affected by age-related differences in the contributions of perceptual vs. conceptual processes, which change across the lifespan and may be targeted in an intervention, and (2) how the structural basis of memory representations changes across the lifespan, which is necessary to understand for an intervention ameliorating age-related memory representation deficits to have long term effects. Here, the applicant proposes an innovative two-prong approach that examines age-related differences in the influence on memory representations of perceptual vs. conceptual processes and brain structural networks. The proposed project will provide mentored training in (1) the assessment of brain/neurocognitive changes in younger and older adults, (2) advanced MRI analysis (e.g., graph theory, deep convolutional neural networks) and (3) multimodal imaging analysis (functional and structural), which are necessary for utilizing the two-prong approach, and (4) career development. The training plan includes coursework, workshops, one- on-one mentorship, participation in seminars, directed readings, and attendance at national and international conferences. In Study 1, while undergoing fMRI, 36 younger adults and 36 older adults study pictures of complex scenes and later retrieve their memories of the scenes. Participants’ use of perceptual and conceptual processes are experimentally manipulated. The goal is to link age-related memory representational quality deficits to age effects in perceptual vs. conceptual processing (Aim 1). The applicant investigates this aim with representational similarity analyses combined with cutting-edge deep convolutional neural networks. In Study 2, the applicant also collects diffusion weighted images to link age-related memory representation quality deficits to age effects on structural brain networks (Aim 2). The applicant investigates this aim with novel graph theory and multimodal imaging (functional and structural) analyses. This investigation using a two- prong approach will provide a novel viewpoint on mechanisms underlying age-related episodic memory decline, which is essential for intervention development. Furthermore, at the culmination of this fellowship, the applicant will have a specialized skill set and be well prepared to begin the next phase of training.