Ansell Judith M, Wouldes Trecia A, Harding Jane E
Liggins Institute, University of Auckland, Auckland, New Zealand.
Department of Psychological Medicine, University of Auckland, Auckland, New Zealand.
PLoS One. 2017 Nov 22;12(11):e0188158. doi: 10.1371/journal.pone.0188158. eCollection 2017.
A growing number of babies are born with perinatal risk factors that may impair later development. These children are often assessed at 2 years to help predict outcome and direct support services. Executive function is an important predictor of academic achievement and behavior, but there are limited assessments of executive function in 2-year-olds and few have been tested in at-risk populations. Therefore, we developed a battery of four age-appropriate tasks to assess executive function in 2-year-olds. At 24 months' corrected age 368 children completed tasks assessing attention, inhibition, working memory and cognitive flexibility. Scores on different tasks were weakly correlated, suggesting that they measured separate aspects of executive function, with combined scores for this cohort approximating a normal distribution. Significantly more boys (67%) than girls (57%) were unable to inhibit their behavior on the Snack Delay Task and girls (M = 3.24, SD = 2.4) had higher mean scores than boys (M = 2.7, SD = 2.7) on the Ducks and Buckets Reverse Categorization Task of working memory. Performance was significantly affected by family socioeconomic status. Mean scores were lower on all four individual tasks and on the global score of overall performance in children from a low household income (<$40,000) compared to those from medium ($40,001-$70,000) and high income households (>$70,001). Maternal education was only associated with scores on the working memory task and the global score; and a measure of neighborhood deprivation was only associated with scores on the two inhibitory tasks and the global score. Our findings confirm the feasibility of assessing executive function in 2-year-olds, and its ability to discriminate effects of socioeconomic status, a common confounder in child development research. Further development and standardization of this test battery comparing at-risk children with a normative population would provide a much-needed measure of executive function in early childhood.
越来越多的婴儿出生时带有可能损害其后期发育的围产期风险因素。这些孩子通常在2岁时接受评估，以帮助预测其发展结果并指导支持服务。执行功能是学业成绩和行为的重要预测指标，但针对2岁儿童的执行功能评估有限，且很少在高危人群中进行测试。因此，我们设计了一组四项适合该年龄段的任务，用于评估2岁儿童的执行功能。在矫正年龄为24个月时，368名儿童完成了评估注意力、抑制能力、工作记忆和认知灵活性的任务。不同任务的得分之间相关性较弱，这表明它们测量的是执行功能的不同方面，该队列的综合得分近似于正态分布。在零食延迟任务中，无法抑制自己行为的男孩（67%）明显多于女孩（57%）；在工作记忆的鸭子和水桶反向分类任务中，女孩（M = 3.24，标准差 = 2.4）的平均得分高于男孩（M = 2.7，标准差 = 2.7）。家庭社会经济地位对表现有显著影响。与来自中等收入（40,001 - 70,000美元）和高收入家庭（>70,001美元）的儿童相比，来自低收入家庭（<40,000美元）的儿童在所有四项单独任务以及整体表现的综合得分上均较低。母亲的教育程度仅与工作记忆任务的得分和综合得分相关；邻里贫困程度的一项指标仅与两项抑制任务的得分和综合得分相关。我们的研究结果证实了评估2岁儿童执行功能的可行性，以及其区分社会经济地位影响的能力，社会经济地位是儿童发展研究中一个常见的混杂因素。将该测试组进一步开发并标准化，与正常人群比较高危儿童，将为幼儿期执行功能提供一项急需的测量指标。
