Deary I J, Bastin M E, Pattie A, Clayden J D, Whalley L J, Starr J M, Wardlaw J M
Department of Psychology, School of Philosophy, Psychology, and Language Sciences, University of Edinburgh, UK.
Neurology. 2006 Feb 28;66(4):505-12. doi: 10.1212/01.wnl.0000199954.81900.e2.
To test the hypothesis that white matter integrity, as measured by diffusion tensor and magnetization transfer MRI is significantly associated with cognitive ability measured in youth and old age.
Forty, nondemented, surviving participants of the Scottish Mental Survey of 1932 underwent brain MRI and a battery of psychometric tests covering major cognitive domains and tests of information processing efficiency. IQ scores were available from age 11. Mean diffusivity, fractional anisotropy (FA), and magnetization transfer ratio (MTR) were measured in frontal and parieto-occipital white matter and centrum semiovale.
Centrum semiovale FA correlated (r = 0.36 to 0.56; p < 0.02) with contemporaneous (age 83) scores on psychometric tests of nonverbal reasoning, working memory, executive function, and information processing efficiency. Centrum semiovale FA also correlated with IQ at age 11 (r = 0.37; p = 0.02). Controlling for IQ at age 11 and information processing at age 83 attenuated the association between centrum semiovale FA and general cognitive ability by approximately 85%. MTR, largely, did not show significant correlations with cognitive test scores.
These data support the information processing efficiency hypothesis of cognitive aging and suggest one foundation for individual differences in processing efficiency. They also suggest that studies of imaging and cognition in the elderly should take into account prior mental ability rather than assuming that any associations between imaging parameters and cognitive test scores are the result of age-related changes.
验证以下假设，即通过扩散张量成像和磁化传递磁共振成像测量的白质完整性与青年和老年时期测量的认知能力显著相关。
1932年苏格兰精神调查的40名未患痴呆症的存活参与者接受了脑部磁共振成像检查以及一系列涵盖主要认知领域和信息处理效率测试的心理测量测试。11岁时的智商分数可用。在前额叶和顶枕白质以及半卵圆中心测量平均扩散率、分数各向异性（FA）和磁化传递率（MTR）。
半卵圆中心的FA与同期（83岁）的非言语推理、工作记忆、执行功能和信息处理效率的心理测量测试分数相关（r = 0.36至0.56；p < 0.02）。半卵圆中心的FA也与11岁时的智商相关（r = 0.37；p = 0.02）。控制11岁时的智商和83岁时的信息处理能力后，半卵圆中心FA与一般认知能力之间的关联减弱了约85%。MTR在很大程度上与认知测试分数没有显著相关性。
这些数据支持认知老化的信息处理效率假说，并为处理效率的个体差异提供了一个基础。它们还表明，老年人成像与认知的研究应考虑先前的心理能力，而不是假设成像参数与认知测试分数之间的任何关联都是与年龄相关变化的结果。
