Duff Kevin, Horn Kevin P, Foster Norman L, Hoffman John M
Center for Alzheimer's Care, Imaging, and Research, Department of Neurology, University of Utah, Salt Lake City, USA
Center for Quantitative Cancer Imaging, Huntsman Cancer Institute, University of Utah, Salt Lake City, USA.
Arch Clin Neuropsychol. 2015 May;30(3):264-70. doi: 10.1093/arclin/acv018.
Practice effects are improvements in cognitive test scores due to repeated exposure to the same tests. Typically viewed as error, short-term practice effects have been shown to provide valuable clinical information about diagnosis, prognosis, and treatment outcomes in older patients with mild cognitive impairments. This study examined short-term practice effects across one week and brain hypometabolism on fluoro-2-deoxyglucose (FDG) positron emission tomography (PET) in 25 older adults (15 intact, 10 Mild Cognitive Impairment). Averaged cerebral brain metabolism on FDG PET was correlated with multiple cognitive scores at baseline in those with Mild Cognitive Impairment, and short-term practice effects accounted for additional variance in these same subjects. The relationship between brain metabolism and cognition (either at baseline or practice effects) was minimal in the intact individuals. Although needing replication in larger samples, short-term practice effects on tests of executive functioning and memory may provide valuable information about biomarkers of Alzheimer's disease.
练习效应是指由于反复接受相同测试而导致认知测试分数提高。短期练习效应通常被视为误差，但已证明它能为患有轻度认知障碍的老年患者提供有关诊断、预后和治疗结果的有价值临床信息。本研究在25名老年人（15名认知功能正常者，10名轻度认知障碍者）中，考察了一周内的短期练习效应以及氟代脱氧葡萄糖（FDG）正电子发射断层扫描（PET）上的脑代谢减低情况。在轻度认知障碍者中，FDG PET上的平均大脑代谢与基线时的多个认知分数相关，并且短期练习效应在这些相同受试者中解释了额外的方差。在认知功能正常的个体中，大脑代谢与认知之间的关系（无论是在基线还是练习效应方面）很小。尽管需要在更大样本中进行重复研究，但执行功能和记忆测试的短期练习效应可能会提供有关阿尔茨海默病生物标志物的有价值信息。
