Hogan Michael J, Carolan Leigh, Roche Richard A P, Dockree Paul M, Kaiser Jochen, Bunting Brendan P, Robertson Ian H, Lawlor Brian A
Department of Psychology, NUI, Galway, Ireland.
Brain Res. 2006 Nov 13;1119(1):215-26. doi: 10.1016/j.brainres.2006.08.075. Epub 2006 Sep 25.
Recent theoretical models of cognitive aging have implicated increased intra-individual variability as a critical marker of decline. The current study examined electrophysiological and information processing variability and memory performance in normal younger and older controls, and older adults with Alzheimer's disease (AD). It was hypothesized that higher levels of variability would be indicative of age-related and disease-related memory deficits. Results indicated both implicit and explicit memory deficits associated with AD. Consistent with previous research, behavioral speed and variability emerged as sensitive to age- and disease-related change. Amplitude variability of P3 event-related potentials was a unique component of electrophysiological activity and accounted for significant variance in reaction time (RT) mean and RT standard deviation, which in turn accounted for significant variance in memory function. Results are discussed in light of theoretical and applied issues in the field of cognitive aging.
近期关于认知衰老的理论模型认为，个体内部变异性增加是衰退的关键标志。本研究考察了正常年轻和老年对照组以及患有阿尔茨海默病（AD）的老年人的电生理和信息处理变异性及记忆表现。研究假设更高水平的变异性将表明与年龄相关和与疾病相关的记忆缺陷。结果表明，AD患者存在内隐和外显记忆缺陷。与先前研究一致，行为速度和变异性对与年龄和疾病相关的变化较为敏感。P3事件相关电位的振幅变异性是电生理活动的一个独特组成部分，它在反应时间（RT）均值和RT标准差中占显著方差，而RT均值和RT标准差又在记忆功能中占显著方差。本文根据认知衰老领域的理论和应用问题对结果进行了讨论。
