Kaup Allison R, Drummond Sean P A, Eyler Lisa T
1Sierra Pacific Mental Illness Research,Education,and Clinical Center,San Francisco VA Medical Center and the Department of Psychiatry,University of California San Francisco,San Francisco,California.
3Psychology Service,VA San Diego Health Care System,San Diego,California.
J Int Neuropsychol Soc. 2014 Oct;20(9):945-50. doi: 10.1017/S1355617714000824. Epub 2014 Sep 29.
We aimed to identify brain functional correlates of working memory performance in aging, in hopes of facilitating understanding of mechanisms that promote better versus worse working memory in late-life. Among 64 healthy adults, aged 23 to 78, we examined the relationship between age, working memory performance, and brain functional response during task performance. We focused on the association between working memory load-modulated functional response and individual differences in performance and whether these function-performance relationships differed with age. As expected, older age was associated with poorer working memory performance. Older age was also associated with reduced load-modulated activation including in bilateral prefrontal and parietal regions and left caudate as well as reduced deactivation including in the medial prefrontal cortex. Contrary to findings of hyperactivation in aging, we found no evidence of increased activation with older age. Positive associations identified between brain response and performance did not differ with age. Our findings suggest that the neural mechanisms underlying better versus worse working memory performance are age-invariant across adulthood, and argue against a pattern of functional reorganization in aging. Results are discussed within the broader literature, in which significant heterogeneity in findings between studies has been common.
我们旨在确定衰老过程中工作记忆表现的大脑功能关联，以期促进对晚年促进工作记忆变好或变差机制的理解。在64名年龄在23岁至78岁之间的健康成年人中，我们研究了年龄、工作记忆表现与任务执行期间大脑功能反应之间的关系。我们重点关注工作记忆负荷调制功能反应与表现个体差异之间的关联，以及这些功能-表现关系是否随年龄而不同。正如预期的那样，年龄较大与较差的工作记忆表现相关。年龄较大还与负荷调制激活减少有关，包括双侧前额叶和顶叶区域以及左侧尾状核，同时与去激活减少有关，包括内侧前额叶皮质。与衰老过程中过度激活的研究结果相反，我们没有发现随着年龄增长激活增加的证据。大脑反应与表现之间的正相关关系并未随年龄而不同。我们的研究结果表明，成年期工作记忆表现变好或变差背后的神经机制在年龄上是不变的，并反对衰老过程中功能重组的模式。我们在更广泛的文献中讨论了这些结果，其中研究结果之间的显著异质性很常见。
