Rhodes Rebecca E, Katz Benjamin
Department of Psychology, University of Michigan.
Psychol Aging. 2017 Feb;32(1):51-59. doi: 10.1037/pag0000135.
The present research explores how the trajectory of learning on a working memory task changes throughout the life span, and whether gains in working memory performance are exclusively a question of initial working memory capacity (WMC) or whether age exerts an independent effect. In a large, cross-sectional study of younger, middle-aged, and older adults, we examined learning on a widely used working memory task-the dual n-back task-over 20 sessions of practice. We found that, while all age groups improved on the task, older adults demonstrated less improvement on the task, and also reached a lower asymptotic maximum performance than younger adults. After controlling for initial WMC, we found that age exerted independent effects on training gains and asymptotic performance; older adults tended to improve less and reached lower levels of performance than younger adults. The difference between younger and older adults' rates of learning depended in part on initial WMC. These results suggest that age-related effects on working memory include not only effects on capacity, but also plasticity and the ability to improve on a task. (PsycINFO Database Record
本研究探讨了在工作记忆任务上的学习轨迹在整个生命周期中是如何变化的，以及工作记忆表现的提升是否仅仅取决于初始工作记忆容量（WMC），还是年龄会产生独立影响。在一项针对年轻人、中年人和老年人的大型横断面研究中，我们通过20次练习课程，对一项广泛使用的工作记忆任务——双重n-back任务的学习情况进行了考察。我们发现，虽然所有年龄组在该任务上都有进步，但老年人的进步较小，并且与年轻人相比，达到的渐近最大表现水平也更低。在控制了初始WMC之后，我们发现年龄对训练收益和渐近表现有独立影响；与年轻人相比，老年人的进步往往较小，且达到的表现水平较低。年轻人和老年人学习速度的差异部分取决于初始WMC。这些结果表明，年龄对工作记忆的影响不仅包括对容量的影响，还包括可塑性和在任务上取得进步的能力。（PsycINFO数据库记录）
