Picq Jean-Luc
Equipe de Recherche en Psychologie Clinique, Université de Paris 8, UFR de Psychologie, 2 rue de la liberté, 93526 Saint Denis cedex, France.
Exp Gerontol. 2007 Mar;42(3):223-32. doi: 10.1016/j.exger.2006.09.013. Epub 2006 Nov 3.
The decline of cognitive capacities with age in mouse lemur primates (Microcebus murinus) was assessed. Eight young adults (2-4 years) and nine aged adults (7-11 years) were examined on tasks designed to measure executive functions, procedural and declarative memory. The mouse lemurs were tested on the go-no go successive discrimination task, set shifting tasks (including extra-dimensional shift and reversal discrimination) and a spatial rule-guided discrimination task. There were four major findings. First, the deficits observed were not global but only on specific tasks indicating that only specific cognitive abilities are impaired with aging. Second, there were variations among aged subjects suggesting different patterns of cognitive aging. Third, alterations in cognitive abilities with aging in mouse lemurs seemed to be comparable to those described in aged monkeys and humans. Indeed, executive functions and declarative memory were affected in subpopulations of aged subjects whereas procedural memory remained intact in all the tested aged subjects. Finally, two forms of executive dysfunctions were distinguished among the aged subjects. The ultimate goal is to correlate age-related cognitive deficit with brain alterations and this study has helped to select candidate regions to be thoroughly scrutinized in aged mouse lemurs.
对小鼠狐猴灵长类动物（倭狐猴）随着年龄增长认知能力的衰退情况进行了评估。研究人员对8只年轻成年个体（2 - 4岁）和9只老年成年个体（7 - 11岁）进行了旨在测量执行功能、程序性记忆和陈述性记忆的任务测试。这些小鼠狐猴接受了去 - 不去连续辨别任务、定势转换任务（包括维度外转换和逆向辨别）以及空间规则引导的辨别任务测试。有四个主要发现。第一，观察到的缺陷并非全局性的，而是仅出现在特定任务中，这表明随着年龄增长只有特定的认知能力会受损。第二，老年个体之间存在差异，这表明认知衰老存在不同模式。第三，小鼠狐猴随着年龄增长认知能力的变化似乎与老年猴子和人类中描述的情况相当。确实，在老年个体亚群中执行功能和陈述性记忆受到了影响，而在所有接受测试的老年个体中程序性记忆保持完好。最后，在老年个体中区分出了两种形式的执行功能障碍。最终目标是将与年龄相关的认知缺陷与大脑变化联系起来，并且这项研究有助于选择在老年小鼠狐猴中进行深入研究的候选区域。
