Cognitive Neuroscience Division, Department of Neurology, Columbia University, New York, NY, United States; Gertrude H. Sergievsky Center, Columbia University, New York, NY, United States.
Cognitive Neuroscience Division, Department of Neurology, Columbia University, New York, NY, United States; Gertrude H. Sergievsky Center, Columbia University, New York, NY, United States; Taub Institute for Research in Alzheimer's Disease and the Aging Brain, Columbia University, New York, NY, United States.
Neurobiol Aging. 2025 Jan;145:76-83. doi: 10.1016/j.neurobiolaging.2024.10.008. Epub 2024 Oct 31.
Aging is often accompanied by changes in brain structure and executive functions, particularly in tasks involving cognitive flexibility, such as task-switching. However, substantial individual differences in the degree of cognitive impairment indicate that some individuals can cope with brain changes more effectively than others, suggesting higher cognitive reserve (CR). This study identified a neural basis for CR by examining the longitudinal relationship between task-related brain activation, structural brain changes, and changes in cognitive performance during an executive task-switching paradigm including single and dual conditions. Fifty-two older individuals were assessed at baseline and followed up after five years. Structural brain changes related to task-switching performance were analyzed using elastic net regression. Task-related functional brain activation was measured using ordinal trends canonical variate analysis (OrT CVA), capturing patterns of activation increasing from single to dual conditions. A differential task-related expression score (dOrT) was calculated as the difference in pattern expression scores between single and dual conditions at baseline. A linear regression model tested whether dOrT moderated the impact of brain changes on changes in switch cost over five years. Results showed a significant interaction between changes in brain structure and dOrT activation on switch cost change, indicating a moderation effect of task-related activation. Higher dOrT buffered the impact of brain structural decline on switch costs, enabling older adults to better cope with age-related brain structural changes and preserve cognitive flexibility. These findings suggest that these task-related activation patterns represent a neural basis for CR.
衰老通常伴随着大脑结构和执行功能的变化，特别是在涉及认知灵活性的任务中，如任务转换。然而，认知损伤程度的个体差异很大，这表明一些人比其他人更能有效地应对大脑变化，这表明更高的认知储备（CR）。本研究通过检查执行任务转换范式（包括单条件和双条件）中与任务相关的大脑激活、结构脑变化和认知表现变化之间的纵向关系，确定了 CR 的神经基础。52 名老年人在基线时进行评估，并在五年后进行随访。使用弹性网络回归分析与任务转换表现相关的结构脑变化。使用有序趋势典型变量分析（OrT CVA）测量与任务相关的功能大脑激活，捕获从单条件到双条件激活增加的模式。作为单条件和双条件下基线时模式表达得分之间的差异，计算了差异任务相关表达得分（dOrT）。线性回归模型测试了 dOrT 是否调节了大脑变化对五年内转换成本变化的影响。结果表明，大脑结构变化和 dOrT 激活之间的变化对转换成本变化有显著的交互作用，表明与任务相关的激活存在调节作用。较高的 dOrT 缓冲了大脑结构下降对转换成本的影响，使老年人能够更好地应对与年龄相关的大脑结构变化并保持认知灵活性。这些发现表明，这些与任务相关的激活模式代表了 CR 的神经基础。
