Preserved Executive Function in High-Performing Elderly is Driven by Large-Scale Recruitment of Prefrontal Cortical Mechanisms
Preserved Executive Function in High-Performing Elderly is Driven by Large-Scale Recruitment of Prefrontal Cortical Mechanisms
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DOI：
10.1002/hbm.20839
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发表时间：
2009-12-01
影响因子：
4.8
通讯作者：
Foxe, John J.
中科院分区：
文献类型：
--
作者：
De Sanctis, Pierfilippo;Gomez-Ramirez, Manuel;Foxe, John J.
事件相关电位的高密度电映射被用来调查的神经过程，允许一些老年受试者保持高水平的执行功能。有两种可能性：（1）老年受试者的高表现是由与年轻人相似的处理机制所支撑的;也就是说，这些个体在整个生命周期中表现出最小的功能衰退，或者（2）保留的功能依赖于成功地招募和放大控制过程，以补偿正常的感觉知觉随年龄的下降。15名年轻参与者和19名老年参与者（后者分为高绩效和低绩效组）定期在字母和数字分类任务之间交替，每三次试验（AAA-BBB-AAA......）在任务之间切换。这允许在转换、重复和准备转换前试验期间询问性能。在任务转换网络的额叶和顶叶组件中观察到了年龄的强大影响。最大的差异起源于前额叶区域，老年受试者产生放大的，更早的，更分化的活动模式。这种前额叶放大只在高绩效（HP）老年人中很明显，并且在参与者为即将到来的任务转换做准备时的转换前试验中最强。使用地形分析和源定位的早期短暂和后期持续活动的分析共同支持了一个独特的和详细的活动模式，在HP-老年人的额叶和顶叶头皮，完全不同的年轻人和低性能的老年人。在此基础上，我们提出保留的执行功能在HP-老年人是由大规模的招聘和增强前额叶皮层机制。《脑地图》30：4198 - 421.4，2009年。(C)2009 Wiley-Liss，Inc.
High-density electrical mapping of event-related potentials was used to investigate the neural processes that permit some elderly subjects to preserve high levels of executive functioning. Two possibilities pertain: (1) high-performance in elderly subjects is underpinned by similar processing mechanisms to those seen in young adults; that is, these individuals display minimal functional decay across the lifespan, or (2) preserved function relies on successfully recruiting and amplifying control processes to compensate for normal sensory-perceptual decline with age. Fifteen young and nineteen elderly participants, the latter split into groups of high and low performers, regularly alternated between a letter and a number categorization task, switching between tasks every third trial (AAA-BBB-AAA...). This allowed for interrogation of performance during switch, repeat, and preparatory pre-switch trials. Robust effects of age were observed in both frontal and parietal components of the task-switching network. Greatest differences originated over prefrontal regions, with elderly subjects generating amplified, earlier, and more differentiated patterns of activity. This prefrontal amplification was evident only in high-performing (HP) elderly, and was strongest on pre-switch trials when participants prepared for an upcoming task-switch. Analysis of the early transient and late sustained activity using topographic analyses and source localization collectively supported a unique and elaborated pattern of activity across frontal and parietal scalp in HP-elderly, wholly different to that seen in both young and low-performing elderly. On this basis, we propose that preserved executive function in HP-elderly is driven by large-scale recruitment and enhancement of prefrontal cortical mechanisms. Hum Brain Mapp 30:4198-421.4, 2009. (C) 2009 Wiley-Liss, Inc.