Neuroimaging of Dedifferentiation and Memory Across the Lifespan

整个生命周期去分化和记忆的神经影像学

• 批准号: 7646271
• 负责人: DENISE CORTIS PARK
• 金额: $ 65.71万
• 依托单位: UNIVERSITY OF TEXAS DALLAS
• 依托单位国家: 美国
• 财政年份: 1985
• 资助国家: 美国
• 起止时间: 1985-09-01 至 2011-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7646271
• 关键词: Accounting; Address; Adult; Age; Aging; Area; Attention; Behavior; Behavioral; Bilateral; Biological Preservation; Brain; Cerebral cortex; Characteristics; Classification; Cognition; Cognitive; Cognitive aging; Complex; Data; Distant; Elderly; Functional Imaging; Funding; Handedness; Health; Hippocampus (Brain); Image; Impaired cognition; Individual Differences; Influentials; Investigation; Joints; Knowledge; Learning; Life Cycle Stages; Literature; Longevity; Measures; Mediating; Memory; Modality; Modeling; Neurocognitive; Neurophysiology - biologic function; Pattern; Performance; Process; Recruitment Activity; Relative (related person); Reporting; Research Personnel; Role; Sampling; Sensory; Short-Term Memory; Specificity; Speed; Structure; Sum; Techniques; Testing; Visual; Visual Cortex; Work; age group; age related; analog; behavior measurement; brain tissue; cognitive function; cognitive neuroscience; extrastriate visual cortex; frontal lobe function; indexing; insight; interest; long term memory; middle age; neural recruitment; neuroimaging; neuromechanism; processing speed; programs; relating to nervous system; sensory cortex; tool; young adult

DESCRIPTION (provided by applicant): In the present proposal, we seek to integrate our years of behavioral work on the cognitive neuroscience of aging with our recent imaging work. The paradox we propose to investigate is as follows. It is the case that cognitive function declines reliably across the lifespan. Yet, rather than neural activations declining along with the cognitive behavior, many investigators have reported evidence for increased frontal activation and more distributed frontal activation with age, particularly bilateral activation. Despite the importance of the finding of increased and more distributed frontal recruitment with age, virtually nothing is known about the normative age when this shift to more distributed frontal lobe function occurs, and whether bilateral recruitment in middle-age is indicative of cognitive health or cognitive decline. We investigate in the present proposal whether middle-aged adults who show patterns of frontal recruitment more similar to elderly will have lower cognitive performance and show decreased function in other neural areas. A second focus of the proposed work relates to our recent findings where we have isolated 2 potential mechanisms (hippocampal function, and neural selectivity in the ventral visual cortex) that we believe to be important determinants of both frontal lobe function and memory performance in older adults. We have demonstrated, like others, that older adults recruit additional frontal areas relative to young on both working memory (Park et al., 2003) and long-term memory (Gutchess et al., 2005) tasks. We also have consistently noted decreased hippocampal function accompanying the increased frontal involvement, and found a direct relationship between the 2, leading us to propose that the increased frontal recruitment in old is at least partially due to decreased hippocampal engagement (Park & Gutchess, 2005). We also have found compelling evidence for decreased neural specialization in the ventral visual cortex with age (Park et al., 2004; Chee et al., in press), and we are able to develop a specific index of neural "dedifferentiation" in ventral visual cortex. We hypothesize that this decreased specialization of sensory cortex is an important factor in enhanced frontal recruitment with age. In sum, in this new project, we propose to conduct the neuroimaging analog of the large lifespan behavioral studies that have come out of our lab (Park et al., 996, 2002). We propose to collect neural data on multiple cognitive tasks, as well as to characterize subjects with a behavioral battery. This work will provide what will be, perhaps, the first lifespan characterization of neurocognitive aging, through an integration of both neuroimaging and behavioral data. We will collect a sample of sufficient size to utilize an individual differences approach, paying particular attention to neural selectivity in ventral visual cortex and hippocampal function as predictors of behavioral performance as well as prefrontal activation. Finally, we propose to integrate structural measures of cortical thinning with behavioral and neural data, and expect that subjects who show cortical thinning in the sensory areas beginning in middle-aged, will be most likely to show neural recruitment patterns typical of older adults.

描述（由申请人提供）：在本提案中，我们试图将衰老的认知神经科学的行为工作与最近的成像工作相结合。我们建议调查的悖论如下。在整个生命周期中，认知功能可靠地下降。然而，许多研究者报告说，与年龄相关的额叶激活增加和额叶的分布更大，尤其是双边激活的证据，而不是神经激活随着认知行为的下降而下降。尽管发现随着年龄的增长而发现增加和分布更分布的额叶招募的重要性，但在这种转变向更分布的额叶功能发生时，几乎没有什么知道的，以及中年的双边招募是否表明认知健康或认知能力下降。我们在本提案中调查了表现出与老年人更相似的额叶招募模式的中年成年人是否具有较低的认知表现，并且在其他神经区域显示功能下降。提出的工作的第二个重点与我们最近的发现有关，在我们的发现中我们认为，我们认为隔离了2种潜在的机制（海马功能和腹侧视觉皮层中的神经选择性），我们认为这是额叶功能和老年人中额叶功能的重要决定因素。我们已经证明，与其他人一样，老年人在工作记忆中招募了相对于年轻人（Park等，2003）和长期记忆（Gutchess等，2005）任务。我们还一直注意到，伴随着额叶的介入增加的海马功能降低，并发现2之间存在直接关系，这使我们提出，旧的额叶募集增加至少部分是由于海马参与度降低了（Park＆Gutchess，2005年）。我们还发现了随着年龄的增长而在腹侧视觉皮层中降低神经专业化的令人信服的证据（Park等，2004; Chee等人，印刷中），我们能够在腹侧视觉皮层中开发特定的神经“ deDiffertivation”指数。我们假设这种减少的感觉皮层专业化是随着年龄的增强额叶募集的重要因素。总而言之，在这个新项目中，我们建议对我们实验室中出现的大型寿命行为研究进行神经影像学类似（Park等，996，2002）。我们建议收集有关多个认知任务的神经数据，并以行为电池电池为单位表征受试者。这项工作将通过整合神经影像学和行为数据来提供神经认知衰老的第一个寿命表征。我们将收集足够大小的样本来利用个体差异方法，特别注意腹侧视觉皮层和海马功能的神经选择性，作为行为性能和前额叶激活的预测指标。最后，我们建议将皮质稀疏的结构测量与行为和神经数据相结合，并期望从中年开始的感觉区域显示皮质稀疏的受试者最有可能显示出典型的老年人的神经招募模式。