Investigating the Mechanisms and Functional Consequences of Age-Related Neural Dedifferentiation

研究年龄相关神经去分化的机制和功能后果

基本信息

批准号：
10230416
负责人：
Cindy S Bergeman
金额：
$ 49.29万
依托单位：
UNIVERSITY OF NOTRE DAME
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-09-15 至 2023-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10230416
关键词：
Address Adopted Adult Age Age-associated memory impairment Animals Brain Brain region Categories Clinical Cognition Cognitive Cognitive aging Complex Computer Models Dementia Early Diagnosis Electroencephalography Episodic memory Event Face Functional Magnetic Resonance Imaging Human Image Impaired cognition Individual Individual Differences Influentials Intelligence Investigation Judgment Knowledge Liquid substance Literature Longevity Measures Memory Loss Nature Neuropsychological Tests Noise Participant Pattern Performance Play Public Health Quality of life Reporting Research Research Proposals Role Scalp structure Semantics Series Silicon Dioxide Standardization Stimulus Structure Structure-Activity Relationship Symptoms Testing Theoretical model Thick Time age difference age effect age related age related neurodegeneration aging brain base cognitive ability cognitive control cognitive function cognitive performance cognitive process cognitive task executive function experimental study healthy aging indexing negative affect neural patterning neuromechanism neuronal patterning neuropathology processing speed programs public health relevance recruit relating to nervous system response sensory stimulus white matter young adult

项目摘要

ABSTRACT: Numerous cognitive abilities, including episodic memory, fluid intelligence and executive function. Even the more modest cognitive impairment typical of healthy people as they reach their 70’sand 80’s can negatively impact quality of life. Moreover, the neuropathology associated with dementia onsets years before the emergence of significant clinical symptoms. This long prodromal period places a premium on early detection of trajectories of ‘unsuccessful’ brain aging. For these reasons, it is important to understand the neural bases of the effects of age on cognitive abilities. The present research aims to elucidate factors contributing to age-related differences in the precision with which perceptual and, possibly conceptual, information is represented in the brain. It has been proposed that age-related neural dedifferentiation – a reduction with age in the selectivity and precision of neural representations – plays a critical role in cognitive aging. We propose a series of studies to identify the potential neural mechanisms and functional significance of this phenomenon. One strand of the research will examine whether the precision and variance of the patterns of neuronal activity elicited by individual stimuli differs with age, as is predicted in an influential theoretical framework. We will also determine whether dedifferentiation for individual stimuli is associated with related reductions in neural selectivity for different stimulus categories. A second strand builds on animal and human research showing that neural selectivity for perceptual stimuli is modulated by task demands. A third strand will determine whether the age-related neural dedifferentiation observed for simple perceptual stimuli extends to complex cognitive tasks, namely, different semantic judgments. In a fourth strand of the research, we will identify whether measures of neural dedifferentiation are associated with individual differences in brain structure and cognitive performance. A final strand will use scalp EEG to examine the temporal dynamics of age-related neural dedifferentiation. Within this strand, we aim to determine if neural differentiation emerges later in time in older relative to younger adults, and if age-related increases in ‘neural noise’ contribute to age-related neural dedifferentiation.

抽象的：许多认知能力，包括情景记忆、流体智力和执行功能，即使是健康人在 70 多岁和 80 多岁时出现的典型认知障碍也会对生活质量产生负面影响。由于这些原因，了解年龄对大脑衰老影响的神经基础非常重要。目前的研究旨在阐明导致大脑中感知信息（可能是概念信息）表达精度的年龄相关差异的因素。有人提出，与年龄相关的神经去分化——随着年龄的增长而减少。神经表征的选择性和精确性——在认知衰老中发挥着关键作用，我们提出了一系列研究来确定这种现象的潜在神经机制和功能意义。该研究的一个部分将检查个体刺激引起的神经活动模式的精度和方差是否随年龄而变化，正如一个有影响力的理论框架所预测的那样，我们还将确定个体刺激的去分化是否与相关的减少有关。第二条链建立在动物和人类研究的基础上，表明感知刺激的神经选择性受到任务需求的调节，第三条链将决定观察到的简单知觉刺激的与年龄相关的神经去分化是否延伸到。复杂的认知任务，即不同的语义判断，在研究的第四部分中，我们将确定神经去分化的测量是否与大脑结构和认知表现的个体差异相关。最后一部分将使用头皮脑电图来检查时间动态。在这一线索中，我们的目标是确定老年人的神经分化是否出现得比年轻人晚，以及“神经噪音”的年龄相关增加是否会导致年龄相关的神经去分化。