Rabbitt Patrick, Scott Marietta, Lunn Mary, Thacker Neil, Lowe Christine, Pendleton Neil, Horan Mike, Jackson Alan
Department of Psychology, University of Manchester, Manchester, United Kingdom.
Neuropsychology. 2007 May;21(3):363-70. doi: 10.1037/0894-4105.21.3.363.
MRI scans measured white matter lesion prevalence (WMLP) in 65 people ages 65-84 years who also took 17 cognitive tests: 3 tests of general fluid intelligence, 3 of vocabulary, 2 of episodic and 3 of working memory, 2 of processing speed, and 4 of frontal and executive function. Entry of age with WMLP into regression equations as predictors of test scores showed that inferences about the functional relationships between markers of brain aging and cognitive impairments are seriously misleading if they are based on simple correlations alone. A new finding that WMLP accounts for all of the age-related variance between individuals in tests of speed and executive ability but for none of the age-related variance in intelligence revises current hypotheses that gross brain changes affect general fluid intelligence and other mental abilities solely through their effects on information-processing speed.
磁共振成像（MRI）扫描测量了65名年龄在65至84岁之间人群的白质病变患病率（WMLP），这些人还进行了17项认知测试：3项一般流体智力测试、3项词汇测试、2项情景记忆测试和3项工作记忆测试、2项处理速度测试，以及4项额叶和执行功能测试。将年龄与WMLP作为预测测试分数的指标纳入回归方程显示，如果仅基于简单相关性，关于大脑衰老标志物与认知障碍之间功能关系的推断会产生严重误导。一项新发现表明，WMLP解释了个体在速度和执行能力测试中所有与年龄相关的差异，但在智力测试中未解释任何与年龄相关的差异，这修正了当前的假设，即大脑的总体变化仅通过对信息处理速度的影响来影响一般流体智力和其他心理能力。
