认知年老化与执行衰退假说

Cognitive Aging and Executive Decline Hypothesis

在认知年老化领域,执行衰退假说是近年来新兴的一种理论。执行衰退假说在理论上具有很强的吸引力,但在实证研究中却存在很多困难,如执行功能的可分离性问题,执行功能测量的信度和效度问题,以及执行功能与加工速度的关系问题。目前,该领域研究的焦点是:在行为学水平上,控制一般性因素(加工速度)后,执行功能是否仍对认知年老化起重要的中介作用;在神经水平上,执行(额叶)功能随龄的变化情况,以及在认知年老化过程中,额叶在大脑功能重组中扮演的角色。最终实现对认知年老化的理解,需要将认知功能与大脑结构联系起来;既看到广泛存在的共同的基本机制,又不能忽略不同认知结构的选择性变化。

Executive decline hypothesis of cognitive aging is an attractive theory proposed in recent years. However, there are some obstacles when put this theory into practice, which including the diversity of executive functions, the reliability and validity of executive function measures, and the relationship between executive function and processing speed. At present, the focuses of the research are whether executive function mediates age differences in cognition after processing speed have been taken into account on behavior level, and which role does it play as brain remodeling with age on neural level. To explore the essence of cognitive aging, we should connect cognitive aging with the brain, and emphasize general mechanism as well as selective changes of the cognitive system.