Executive function assessment in New Zealand 2-year olds born at risk of neonatal hypoglycemia

Abstract

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.

Measuring and Predicting Individual Differences in Executive Functions at 14 Months: A Longitudinal Study

“…Unlike in later childhood (e.g., Willoughby et al., ), but consistent with previous studies of 12‐ to 15‐month‐old children using smaller samples, we found no evidence for consistent correlations between distinct measures of EF at 14 months. Our results also mirror the weak and inconsistent correlations between EF tasks in large studies of children aged between 20 and 37 months (Ansell et al., ; Mulder et al., ). It is therefore unlikely that the lack of correlations among EF tasks in initial studies (e.g., Johansson et al., ; Miller & Marcovitch, ) was due to their small sample sizes.…”

“…Mirroring trends in EF research on children aged 24 months and over (e.g., Ansell, Wouldes, & Harding, ; Carlson, ; Garon, Smith, & Bryson, ; Hughes & Ensor, ; Leve et al., ; Mulder, Hoofs, Verhagen, Van der Veen, & Leseman, ; Wiebe, Espy, & Charak, ), researchers have extended the task battery approach to research on infants aged between 12 and 15 months (Johansson, Marciszko, Brocki, & Bohlin, ; Miller & Marcovitch, ; Wiebe, Lukowski, & Bauer, ). These studies have combined EF tasks previously studied in isolation to construct task batteries that include: (a) response inhibition tasks in which infants refrained from touching an attractive toy (e.g., a glittery wand; Miller & Marcovitch, ; Johansson et al., ); (b) the A‐not‐B or similar tasks (Miller & Marcovitch, ; Wiebe et al., ); (c) the Three Boxes task in which infants searched for toys hidden in three distinct locations (Miller & Marcovitch, ; Wiebe et al., ); and (d) sorting tasks in which infants learned to sort objects according to one rule and then sorted the same objects according to a different rule (Johansson et al., ; Miller & Marcovitch, ).…”

Neurocognitive Outcomes at Age 2 Years After Neonatal Hypoglycemia in a Cohort of Participants From the hPOD Randomized Trial

“…Furthermore, our inception cohort comprised participants in a randomized clinical trial that specified glucose testing using standard methods and prospective follow-up using standardized assessments. 14,15 In contrast, some previous studies collected data retrospectively using hospital records, potentially increasing the risk of bias in assessment of exposures and outcomes. 9,19 We found that even children who had experienced brief transitional hypoglycemia and were screened and treated with the intention of maintaining blood glucose concentrations greater than or equal to 47 mg/dL are at increased risk of neurodevelopmental impairment.…”

Gender differences in inhibitory control as assessed on simple delay tasks in early childhood: A meta-analysis

“…Thus, in the study by Jaekel et al (2016) in which children born preterm were compared with children born full term, only the data for the latter group are used here. A borderline case is a study by Ansell et al (2017) in which the sample was composed of children who were diagnosed as being at risk for hypoglycemia during the perinatal period. However, as the study report does not indicate whether any of the children were diagnosed as diabetic at age 2 (when simple delay task performance was assessed), presumably the great majority of them were typically developing at that age.…”