Vonk Jet M J, Flores Roxanna J, Rosado Dayanara, Qian Carolyn, Cabo Raquel, Habegger Josina, Louie Karmen, Allocco Elizabeth, Brickman Adam M, Manly Jennifer J
Taub Institute for Research on Alzheimer's Disease and the Aging Brain.
Neuropsychology. 2019 Feb;33(2):256-262. doi: 10.1037/neu0000508. Epub 2018 Nov 29.
Accurate identification of the earliest cognitive changes associated with Alzheimer's disease (AD) is critically needed. Item-level information within tests of category fluency, such as lexical frequency, harbors valuable information about the integrity of semantic networks affected early in AD. To determine the potential of lexical frequency as a cognitive marker of AD risk, we investigated whether lexical frequency of animal fluency output differentiated ε4 carriers from noncarriers in a cross-sectional design among older African-American adults without dementia.
We analyzed animal fluency performance using mean number of items and mean lexical frequency among 230 cognitively normal African Americans with and without the ε4 allele.
Lexical frequency was higher in ε4 carriers than noncarriers when analyzed as a mean score and within time bins. In contrast, we found no group difference in the number of items produced. Lexical frequency was particularly sensitive to ε4 status after the first 10 s of the 60-s animal fluency task.
Our results suggest that psycholinguistic features may hold value as a cognitive biomarker for identifying people at high risk of AD. (PsycINFO Database Record (c) 2019 APA, all rights reserved).
迫切需要准确识别与阿尔茨海默病（AD）相关的最早认知变化。类别流畅性测试中的项目级信息，如词汇频率，包含有关AD早期受影响语义网络完整性的宝贵信息。为了确定词汇频率作为AD风险认知标志物的潜力，我们在一项横断面设计中，研究了动物流畅性输出的词汇频率是否能区分老年非痴呆非裔美国成年人中的ε4携带者和非携带者。
我们分析了230名有或没有ε4等位基因的认知正常非裔美国人的动物流畅性表现，使用项目平均数和词汇频率平均数。
将词汇频率作为平均分数分析以及在时间区间内分析时，ε4携带者的词汇频率高于非携带者。相比之下，我们发现产出的项目数量没有组间差异。在60秒动物流畅性任务的前10秒之后，词汇频率对ε4状态特别敏感。
我们的结果表明，心理语言学特征可能作为一种认知生物标志物，对识别AD高风险人群具有价值。（《心理学文摘数据库记录》（c）2019美国心理学会，保留所有权利）
