Grand Jacob H G, Stawski Robert S, MacDonald Stuart W S
a Department of Psychology , University of Victoria , Victoria, BC , Canada.
c Centre on Aging, University of Victoria , Victoria, BC , Canada.
J Clin Exp Neuropsychol. 2016;38(5):534-50. doi: 10.1080/13803395.2015.1136598. Epub 2016 Feb 22.
Recent theorizing differentiates key constraints on cognition, including one's current range of processing efficiency (i.e., flexibility or inconsistency) as well as the capacity to expand flexibility over time (i.e., plasticity). The present study uses intensive assessment of response time data to examine the interplay between markers of intraindividual variability (inconsistency) and gains across biweekly retest sessions (plasticity) in relation to age-related cognitive function.
Participants included 304 adults (aged 64 to 92 years: M = 74.02, SD = 5.95) from Project MIND, a longitudinal burst design study assessing performance across micro and macro intervals (response latency trials, weekly bursts, annual retests). For two reaction time (RT) measures (choice RT and one-back choice RT), baseline measures of RT inconsistency (intraindividual standard deviation, ISD, across trials at the first testing session) and plasticity (within-person performance gains in average RT across the 5 biweekly burst sessions) were computed and were then employed in linear mixed models as predictors of individual differences in cognitive function and longitudinal (6-year) rates of cognitive change.
Independent of chronological age and years of education, higher RT inconsistency was associated uniformly with poorer cognitive function at baseline and with increased cognitive decline for measures of episodic memory and crystallized verbal ability. In contrast, predictive associations for plasticity were more modest for baseline cognitive function and were absent for 6-year cognitive change.
These findings underscore the potential utility of response times for articulating inconsistency and plasticity as dynamic predictors of cognitive function in older adults.
最近的理论研究区分了对认知的关键限制，包括一个人当前的处理效率范围（即灵活性或不一致性）以及随着时间推移扩展灵活性的能力（即可塑性）。本研究通过对反应时间数据进行密集评估，来检验个体内部变异性（不一致性）指标与双周复测期间的进步（可塑性）之间的相互作用，这些指标与年龄相关的认知功能有关。
参与者包括来自“MIND计划”的304名成年人（年龄在64至92岁之间：M = 74.02，SD = 5.95），“MIND计划”是一项纵向突发设计研究，评估了微观和宏观时间间隔内的表现（反应潜伏期试验、每周突发、年度复测）。对于两项反应时间（RT）测量（选择反应时间和单背选择反应时间），计算了RT不一致性（个体内部标准差，ISD，在第一次测试会话的各次试验中）和可塑性（在5个双周突发会话中平均RT的个体内表现进步）的基线测量值，然后将其用于线性混合模型，作为认知功能个体差异和纵向（6年）认知变化率的预测指标。
独立于实际年龄和受教育年限，较高的RT不一致性始终与基线时较差的认知功能相关，并且与情景记忆和晶态语言能力测量中的认知衰退增加相关。相比之下，可塑性对基线认知功能的预测关联更为适度，对6年认知变化则不存在预测关联。
这些发现强调了反应时间在阐明不一致性和可塑性作为老年人认知功能动态预测指标方面的潜在效用。
