TY - JOUR T1 - Early Childcare, Executive Functioning, and the Moderating Role of Early Stress Physiology. JF - Developmental Psychology Y1 - 2013 A1 - Berry, Daniel A1 - Clancy Blair A1 - Ursache, Alexandra A1 - Michael T. Willoughby A1 - Granger, Douglas A. AB -

Intervention studies indicate that children’s childcare experiences can be leveraged to support the development of executive functioning (EF). The role of more normative childcare experiences is less clear. Increasingly, theory and empirical work suggest that individual differences in children’s physiological stress systems may be associated with meaningful differences in the way they experience these early environments. Using data from a large population-based sample of predominantly low-income rural families, we tested the degree to which children’s childcare experiences—quantity, quality, and type—in the first 3 years of life predicted emerging EF. Moreover, we examined whether these effects varied as a function of children’s basal cortisol levels in infancy and toddlerhood— an indicator of hypothalamic pituitary adrenal (HPA) axis stress physiology. Our results showed that higher quality care predicted more effective EF at 48 months, irrespective of quantity or type. This relation did not vary as a function of children’s early cortisol levels. Attending greater hours of care per week was also related to EF; however—consistent with theory—the positive association between spending more time in childcare and more positive EF extended only to children with low levels of basal cortisol at 7 or 24 months of age. Attending center-based care was unassociated with EF. (PsycINFO Database Record (c) 2013 APA, all rights reserved)

UR - http://doi.apa.org/getdoi.cfm?doi=10.1037/a0034700 JO - Developmental Psychology ER - TY - JOUR T1 - Measuring executive function in early childhood: A focus on maximal reliability and the derivation of short forms. JF - Psychological Assessment Y1 - 2013 A1 - Michael T. Willoughby A1 - Pek, Jolynn A1 - Clancy Blair AB -

This study assesses the maximal reliability of a newly developed battery of executive function (EF) tasks for use in early childhood. It also demonstrates how changes in maximal reliability can inform the selection of different short forms of the battery, depending on child age. Participants included children from the Family Life Project (Vernon-Feagans, Cox, & Family Life Project Investigators, in press)—a prospective longitudinal study (N = 1,292) of families that were recruited at the time of the birth of a new child—who were assessed at ages 3, 4, and 5 years. Results indicate that the EF battery had reasonably good maximal reliability (ρ = .73, 95% confidence interval [CI] = .69, .76) in a mixed-age sample of children randomly selected from assessments at ages 3, 4, and 5. In contrast, maximal reliability of the battery ranged from poor to modest for within-age samples (ρs = .47 [95% CI = .37, .52], .62 [.57, .66], and .61 [.55, .66] at ages 3, 4, and 5, respectively). Although the derivation of a 3-task short form of the battery always resulted in statistically significant decrements in maximal reliability, in some cases the relative decrement was quite modest and may be tolerable given the time savings and potential reduction in participant burden. The benefits of using maximal reliability to both evaluate task batteries and derive short forms are discussed, as well as how a focus on maximal reliability informs ongoing questions about the measurement and conceptualization of EF in early childhood. (PsycINFO Database Record (c) 2013 APA, all rights reserved)

VL - 25 UR - http://doi.apa.org/getdoi.cfm?doi=10.1037/a0031747 IS - 2 JO - Psychological Assessment ER - TY - JOUR T1 - Poverty as a predictor of 4-year-olds' executive function: New perspectives on models of differential susceptibility. JF - Developmental Psychology Y1 - 2013 A1 - Cybele Raver A1 - Clancy Blair A1 - Michael T. Willoughby AB -

In a predominantly low-income, population-based longitudinal sample of 1,259 children followed from birth, results suggest that chronic exposure to poverty and the strains of financial hardship were each uniquely predictive of young children's performance on measures of executive functioning. Results suggest that temperament-based vulnerability serves as a statistical moderator of the link between poverty-related risk and children's executive functioning. Implications for models of ecology and biology in shaping the development of children's self-regulation are discussed. (PsycINFO Database Record (c) 2013 APA, all rights reserved)

VL - 49 UR - http://doi.apa.org/getdoi.cfm?doi=10.1037/a0028343 IS - 2 JO - Developmental Psychology ER - TY - JOUR T1 - Executive function in early childhood: Longitudinal measurement invariance and developmental change. JF - Psychological Assessment Y1 - 2012 A1 - Michael T. Willoughby A1 - Wirth, R. J. A1 - Clancy Blair AB -

This study tested the longitudinal measurement invariance and developmental changes of a newly developed battery of executive function (EF) tasks for use in early childhood. The battery was administered in the Family Life Project—a prospective longitudinal study (N = 1,292) of families who were oversampled from low-income and African American families at the birth of a new child—at assessments conducted when the child was 3, 4, and 5 years old. All 6 individual EF tasks exhibited strong measurement invariance over time. The EF battery, which was derived from the 6 individual tasks, exhibited partial strong invariance over time. Second-order latent growth curve models revealed individual differences in the levels but not rates of change in latent EF ability. The functional form of change was nonlinear; 60% of the total change in EF ability that was observed between the 3- and 5-year assessments occurred between the Year 3 and Year 4 assessments. Results are discussed with respect to the importance of establishing scalable measures of EF ability prior to investigating experiences that predict or are predicted by changes in EF during early childhood. (PsycINFO Database Record (c) 2012 APA, all rights reserved)

VL - 24 UR - http://doi.apa.org/getdoi.cfm?doi=10.1037/a0025779 IS - 2 JO - Psychological Assessment ER - TY - JOUR T1 - The measurement of executive function at age 5: Psychometric properties and relationship to academic achievement. JF - Psychological Assessment Y1 - 2012 A1 - Michael T. Willoughby A1 - Clancy Blair A1 - Wirth, R. J. A1 - Mark T. Greenberg AB -

This study examined the psychometric properties and criterion validity of a newly developed battery of executive function (EF) tasks for use in early childhood. The battery was included in the Family Life Project (FLP), a prospective longitudinal study of families who were oversampled from low-income and African American families at the birth of a new child (N = 1,292). Ninety-nine percent (N = 1,036) of children who participated in the age 5 home visit completed 1 or more (M = 5.8, Mdn = 6) of the 6 EF tasks. Results indicated that tasks worked equally well for children residing in low-income and not low-income homes, that task scores were most informative about the ability level of children in the low-average range, that performance on EF tasks was best characterized by a single factor, and that individual differences on the EF battery were strongly related to a latent variable measuring overall academic achievement, as well as to individual standardized tests that measured phonological awareness, letter–word identification, and early math skills. (PsycINFO Database Record (c) 2012 APA, all rights reserved)

VL - 24 UR - http://doi.apa.org/getdoi.cfm?doi=10.1037/a0025361 IS - 1 JO - Psychological Assessment ER - TY - JOUR T1 - Salivary alpha-amylase and cortisol in infancy and toddlerhood: Direct and indirect relations with executive functioning and academic ability in childhood JF - Psychoneuroendocrinology Y1 - 2012 A1 - Berry, Daniel A1 - Clancy Blair A1 - Michael T. Willoughby A1 - Granger, Douglas A. KW - Academic achievement KW - Early childhood KW - executive function KW - Salivary alpha-amylase KW - Salivary cortisol AB -

Using data from a predominantly low-income, population-based prospective longitudinal sample of 1292 children followed from birth, indicators of children's autonomic (salivary alpha-amylase; sAA) and hypothalamic–pituitary–adrenal (HPA) axis (salivary cortisol) activity at 7, 15, and 24 months of age were found to predict executive functioning at 36-months and academic achievement in pre-kindergarten. The findings suggested that the respective cortisol and sAA effects on executive functioning and academic achievement were interactive. Optimal developmental outcomes were associated with asymmetrical cortisol/sAA profiles. Higher cortisol levels were predictive of lower executive functioning and academic abilities, but only for those with concurrently moderate to high levels of sAA. In contrast, higher sAA concentrations were predictive of better executive functioning and academic abilities, but only for those with concurrently moderate to low levels of cortisol. These relations were statistically identical across infancy and toddlerhood. The conditional effects of cortisol and sAA on pre-kindergarten academic achievement were mediated fully by links between these early physiological indicators and executive functioning.

VL - 37 UR - http://linkinghub.elsevier.com/retrieve/pii/S0306453012000881 IS - 10 JO - Psychoneuroendocrinology ER - TY - JOUR T1 - Contributions of modern measurement theory to measuring executive function in early childhood: An empirical demonstration JF - Journal of Experimental Child Psychology Y1 - 2011 A1 - Michael T. Willoughby A1 - Wirth, R.J. A1 - Clancy Blair KW - Early childhood KW - executive function KW - Item response theory KW - Measurement KW - preschool KW - Psychometrics AB -

This study demonstrates the merits of evaluating a newly developed battery of executive function tasks, designed for use in early childhood, from the perspective of item response theory (IRT). The battery was included in the 48-month assessment of the Family Life Project, a prospective longitudinal study of 1292 children oversampled from low-income and African American families. IRT models were applied to a select set of tasks to demonstrate empirically (a) a principled method for item evaluation, including the utility of item characteristic curves; (b) how to explicitly test whether the measurement properties of executive function tasks are invariant across mutually exclusive subgroups of youths; (c) how the precision of measurement of a given task can vary according to underlying child ability; and (d) the utility of using IRT-based versus percentage correct scores. Results are discussed with respect to the importance of developing psychometrically sound and scalable instruments that facilitate the measurement of interindividual differences in intraindividual change of executive function across the early childhood period.

VL - 108 UR - http://linkinghub.elsevier.com/retrieve/pii/S0022096510000676 IS - 3 JO - Journal of Experimental Child Psychology ER - TY - JOUR T1 - EEG power and coherence during preschoolers' performance of an executive function battery JF - Developmental Psychobiology Y1 - 2011 A1 - Swingler, Margaret M. A1 - Michael T. Willoughby A1 - Calkins, Susan D. KW - development KW - EEG coherence KW - EEG power KW - executive function KW - frontal lobe KW - preschool AB -

The current study investigated a set of abilities collectively referred to as executive function (EF). Substantial improvement in EF ability occurs between 3 and 6 years of age (e.g., Carlson [2005] Developmental Neuropsychology, 28(2):595–616). This improvement is thought to reflect changes in brain development, especially in areas of prefrontal cortex and frontal cortex, which occur during this time period (e.g., Luu & Posner [2003] Brain 126:2119–2120). Little work has examined preschoolers' cortical activity during EF tasks, despite the frequent use of performance on such tasks as indirect measures of (pre)frontal functioning. The current study measured continuous EEG activity in 104 preschool aged children as they completed a battery of EF tasks. Changes from baseline to task performance in EEG activity (power, coherence) were used as predictors of EF ability. Results indicated that changes from baseline to task engagement in EEG coherence, but not EEG power, were significantly related to performance on the EF battery in our sample. © 2011 Wiley Periodicals, Inc. Dev Psychobiol 53:771–784, 2011.

VL - 53 UR - http://doi.wiley.com/10.1002/dev.v53.8http://doi.wiley.com/10.1002/dev.20588 IS - 8 JO - Dev. Psychobiol. ER - TY - JOUR T1 - Salivary Cortisol Mediates Effects of Poverty and Parenting on Executive Functions in Early Childhood JF - Child Development Y1 - 2011 A1 - Clancy Blair A1 - Granger, Douglas A. A1 - Michael T. Willoughby A1 - Mills-Koonce, Roger A1 - Cox, Martha A1 - Mark T. Greenberg A1 - Kivlighan, Katie T. A1 - Fortunato, Christine K. AB -

In a predominantly low-income population-based longitudinal sample of 1,292 children followed from birth, higher level of salivary cortisol assessed at ages 7, 15, and 24 months was uniquely associated with lower executive function ability and to a lesser extent IQ at age 3 years. Measures of positive and negative aspects of parenting and household risk were also uniquely related to both executive functions and IQ. The effect of positive parenting on executive functions was partially mediated through cortisol. Typical or resting level of cortisol was increased in African American relative to White participants. In combination with positive and negative parenting and household risk, cortisol mediated effects of income-to-need, maternal education, and African American ethnicity on child cognitive ability.

VL - 82 UR - http://doi.wiley.com/10.1111/cdev.2011.82.issue-6http://doi.wiley.com/10.1111/j.1467-8624.2011.01643.x IS - 6 ER - TY - JOUR T1 - Test-retest reliability of a new executive function battery for use in early childhood JF - Child Neuropsychology Y1 - 2011 A1 - Michael T. Willoughby A1 - Clancy Blair KW - Early childhood KW - executive function KW - Latent variables KW - preschool KW - Retest reliability AB -

This study reported test-retest reliability for a newly developed executive function battery designed for use in early childhood. A total of 140 predominantly low-income children (M = 48.1 months; 51% male; 43% African American) completed up to six tasks on two occasions an average of 18 (Mdn = 16) days apart. Pearson correlations between individual task scores indicated moderate retest reliability (mean r  = .60; range = .52−.66) similar to that observed in other retest studies of executive function in preschool, school-aged, and adult samples. In contrast, confirmatory factor analyses of performance on the task battery across time indicated high retest reliability (  = .95) that was identical to that observed in a recent study that used an identical method involving a sample of older adults. The short-term test-retest reliability of executive function in early childhood is comparable to that observed in childhood and adult samples. The retest reliability of children's performance on batteries of executive function tasks is appreciably stronger than the retest reliability of their performance on individual tasks. Studies that focus on inter- and intraindividual differences in executive function would be better served by using scores that are derived from task batteries than those derived from individual tasks.

VL - 17 UR - http://www.tandfonline.com/doi/abs/10.1080/09297049.2011.554390 IS - 6 JO - Child Neuropsychology ER - TY - JOUR T1 - The measurement of executive function at age 3 years: Psychometric properties and criterion validity of a new battery of tasks. JF - Psychological Assessment Y1 - 2010 A1 - Michael T. Willoughby A1 - Clancy Blair A1 - Wirth, R. J. A1 - Mark T. Greenberg AB -

In this study, the authors examined the psychometric properties and criterion validity of a newly developed battery of tasks that were designed to assess executive function (EF) abilities in early childhood. The battery was included in the 36-month assessment of the Family Life Project (FLP), a prospective longitudinal study of 1,292 children oversampled from low-income and African American families. Ninety-one percent of children were able to complete 1 or more of the tasks. Psychometric analyses were used to test the dimensionality of each task, evaluate the item and task properties, test the dimensionality of the task battery, and evaluate the criterion validity of the battery with multi-informant measures of attention-deficit/hyperactivity disorder (ADHD) symptomatology and child performance on two subtests of the Wechsler Preschool and Primary Scale of Intelligence. Results indicated that the tasks were successful in measuring interindividual differences in child EF ability, that task scores were most informative about ability level for children in the low to moderate range of ability, that children's performance across the entire battery was adequately summarized by a single factor, and that individual differences on the EF battery were related to ADHD symptomatology and intelligence in expected ways. Results are discussed with respect to the importance of developing psychometrically sound, scalable instruments that facilitate the measurement of interindividual differences in intraindividual change of EF across the early childhood period. (PsycINFO Database Record (c) 2012 APA, all rights reserved)

VL - 22 UR - http://doi.apa.org/getdoi.cfm?doi=10.1037/a0018708 IS - 2 JO - Psychological Assessment ER -