Under-recruitment and nonselective recruitment: Dissociable neural mechanisms associated with aging
Under-recruitment and nonselective recruitment: Dissociable neural mechanisms associated with aging
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DOI：
10.1016/s0896-6273(02)00612-8
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发表时间：
2002-02-28
期刊：
影响因子：
16.2
通讯作者：
Buckner, RL
中科院分区：
文献类型：
--
作者：
Logan, JM;Sanders, AL;Buckner, RL
使用功能性MRI探讨了额叶对衰老认知能力下降的贡献。年轻人在自我启动（有意）记忆编码过程中活跃的额叶区域在老年人中招募不足。老年人表现出较少的活动，在前腹区与控制使用的语义信息。招聘不足被逆转，需要语义阐述表明它源于困难，自发招聘可用的额叶资源。此外，老年人招募多个额叶区域在非选择性的方式为语言和非语言材料。缺乏选择性是不可逆的语义定向编码，即使在招聘不足减少。这些发现表明，额叶皮层的年龄相关变化有两种不同的形式：招募不足和非选择性招募。前者是可逆的，可能适合于认知训练;后者可能反映了与晚期衰老中认知下降相关的可塑性较低的变化。
Frontal contributions to cognitive decline in aging were explored using functional MRI. Frontal regions active in younger adults during self-initiated (intentional) memory encoding were under-recruited in older adults. Older adults showed less activity in anterior-ventral regions associated with controlled use of semantic information. Under-recruitment was reversed by requiring semantic elaboration suggesting it stemmed from difficulty in spontaneous recruitment of available frontal resources. In addition, older adults recruited multiple frontal regions in a nonselective manner for both verbal and nonverbal materials. Lack of selectivity was not reversed during semantically directed encoding even when under-recruitment was diminished. These findings suggest two separate forms of age-associated change in frontal cortex: under-recruitment and nonselective recruitment. The former is reversible and potentially amenable to cognitive training; the latter may reflect a less malleable change associated with cognitive decline in advanced aging.