Cognitive Abilities In Early Childhood Research Articles

Changes in frontal EEG coherence across infancy predict cognitive abilities at age 3: The mediating role of attentional control.

Theoretical perspectives of cognitive development have maintained that functional integration of the prefrontal cortex across infancy underlies the emergence of attentional control and higher cognitive abilities in early childhood. To investigate these proposed relations, we tested whether functional integration of prefrontal regions across the second half of the first year predicted observed cognitive performance in early childhood 1 year prior indirectly through observed attentional control (N = 300). Results indicated that greater change in left-but not right-frontal EEG coherence between 5 and 10 months was positively associated with attentional control, cognitive flexibility, receptive language, and behavioral inhibitory control. Specifically, a larger increase in coherence between left frontal regions was positively associated with accuracy on a visual search task at Age 2, and visual search accuracy was positively associated with receptive vocabulary, performance on a set-shifting task (DCCS), and delay of gratification at Age 3. Finally, the indirect effects from the change in left frontal EEG coherence to 3-year cognitive flexibility, receptive language, and behavioral inhibitory control were significant, suggesting that internally controlled attention is a mechanism through which early neural maturation influences children's cognitive development. (PsycINFO Database Record

Do early life cognitive ability and self-regulation skills explain socio-economic inequalities in academic achievement? An effect decomposition analysis in UK and Australian cohorts

Socio-economic inequalities in academic achievement emerge early in life and are observed across the globe. Cognitive ability and “non-cognitive” attributes (such as self-regulation) are the focus of many early years’ interventions. Despite this, little research has compared the contributions of early cognitive and self-regulation abilities as separate pathways to inequalities in academic achievement. We examined this in two nationally representative cohorts in the UK (Millennium Cohort Study, n = 11,168; 61% original cohort) and Australia (LSAC, n = 3028; 59% original cohort).An effect decomposition method was used to examine the pathways from socio-economic disadvantage (in infancy) to two academic outcomes: ‘low’ maths and literacy scores (based on bottom quintile) at age 7–9 years. Risk ratios (RRs, and bootstrap 95% confidence intervals) were estimated with binary regression for each pathway of interest: the ‘direct effect’ of socio-economic disadvantage on academic achievement (not acting through self-regulation and cognitive ability in early childhood), and the ‘indirect effects’ of socio-economic disadvantage acting via self-regulation and cognitive ability (separately). Analyses were adjusted for baseline and intermediate confounding.Children from less advantaged families were up to twice as likely to be in the lowest quintile of maths and literacy scores. Around two-thirds of this elevated risk was ‘direct’ and the majority of the remainder was mediated by early cognitive ability and not self-regulation. For example in LSAC: the RR for the direct pathway from socio-economic disadvantage to poor maths scores was 1.46 (95% CI: 1.17–1.79). The indirect effect of socio-economic disadvantage through cognitive ability (RR = 1.13 [1.06–1.22]) was larger than the indirect effect through self-regulation (1.05 [1.01–1.11]). Similar patterns were observed for both outcomes and in both cohorts.Policies to alleviate social inequality (e.g. child poverty reduction) remain important for closing the academic achievement gap. Early interventions to improve cognitive ability (rather than self-regulation) also hold potential for reducing inequalities in children's academic outcomes.

Gestational Age and Cognitive Ability in Early Childhood: a Population‐based Cohort Study

Recent studies suggest that children born at late preterm (34-36 weeks gestation) and early term (37-38 weeks) may have poorer developmental outcomes than children born at full term (39-41 weeks). We examined how gestational age is related to cognitive ability in early childhood using the U.K. Millennium Cohort Study. Cognitive development was assessed using Bracken School Readiness Assessment at age 3 years, British Ability Scales II at ages 3, 5 and 7 years and Progress in Mathematics at age 7 years. Sample size varied according to outcome between 12,163 and 14,027. Each gestational age group was compared with the full-term group using differences in z-scores and risk ratios for scoring more than -1 SD below the mean. Children born at <32 weeks gestation scored lower (P < 0.05) than the full-term group on all scales with unadjusted z-score differences ranging between -0.8 to -0.2 SD. In all groups, there was an increased risk (P < 0.05) of scoring less than -1 SD below the mean compared with the full-term group for some of the tests: those born at < 32 weeks had a 40-140% increased risk in seven tests, those born at 32-33 weeks had a 60-80% increased risk in three tests, those born at 34-36 weeks had a 30-40% increased risk in three tests, and those born at 37-38 weeks had a 20% increased risk in two tests. Cognitive ability is related to the entire range of gestational age, including children born at 34-36 and 37-38 weeks gestation.

A population-based cohort study of gestational age and cognitive ability in early childhood

ObjectiveTo examine how cognitive ability is related to gestational age and the extent to which observed differences could be explained by socio-economic confounding.MethodsThe Millennium Cohort Study collected data on 18...

SES and CHAOS as environmental mediators of cognitive ability: A longitudinal genetic analysis

This study examined shared environmental influences on the longitudinal stability of general cognitive ability, as mediated by socioeconomic status and chaos in the home, using 287 pairs of elementary school-age twins drawn from the Western Reserve Reading Project (WRRP). General cognitive ability was evaluated at two annual assessments using the Stanford-Binet Intelligence Test. SES was examined using the highest level of education achieved by the mother of the twins, and chaos by a 6-item parent-report questionnaire. Results suggest that SES and CHAOS not only account for independent sources of shared environmental influences related to general cognitive ability at a given measurement occasion, but these effects also account for a portion of the longitudinal stability of general cognitive ability in early childhood.

Brain Basis of Developmental Change in Visuospatial Working Memory

Although brain changes associated with the acquisition of cognitive abilities in early childhood involve increasing localized specialization, little is known about the brain changes associated with the refinement of existing cognitive abilities that reach maturity in adolescence. The goal of this study was to investigate developmental changes in functional brain circuitry that support improvements in visuospatial working memory from childhood to adulthood. We tested thirty 8- to 47-year-olds in an oculomotor delayed response task. Developmental transitions in brain circuitry included both quantitative changes in the recruitment of necessary working memory regions and qualitative changes in the specific regions recruited into the functional working memory circuitry. Children recruited limited activation from core working memory regions (dorsal lateral prefrontal cortex [DLPFC] and parietal regions) and relied primarily on ventromedial regions (caudate nucleus and anterior insula). With adolescence emerged a more diffuse network (DLPFC, anterior cingulate, posterior parietal, anterior insula) that included the functional integration of premotor response preparation and execution circuitry. Finally, adults recruited the most specialized network of localized regions together with additional performance-enhancing regions, including left-lateralized DLPFC, ventrolateral prefrontal cortex, and supramarginal gyrus. These results suggest that the maturation of adult-level cognition involves a combination of increasing localization within necessary regions and their integration with performance-enhancing regions.

A longitudinal genetic analysis of low verbal and nonverbal cognitive abilities in early childhood.

By middle childhood, the same genetic factors are largely responsible for individual differences in verbal and nonverbal abilities, suggesting a genetic basis for general cognitive ability ("g"). Our previous work on verbal and nonverbal abilities throughout the normal range of variation during infancy and early childhood suggests that genetic influences show domain-specific as well as domain-general effects, implying that the switch to nearly complete domain-general effects occurs later in development. Much less is known about the genetic structure of low cognitive performance, although our previous work has shown that a composite measure of low "g" is highly heritable at 2, 3 and 4 years of age. We report the first multivariate, longitudinal analyses of low verbal and nonverbal cognitive abilities (defined as the lowest 10% of the distribution) at 2, 3 and 4 years of age using data from 9026 pairs of UK twins assessed by their parents as part of the Twins Early Development Study (TEDS). Domain-general genetic influences increased significantly from 2 to 3 to 4 years. Although the phenotypic polychoric correlation between low verbal and low nonverbal ability was similar at 2, 3 and 4 years (.36,.43,.35), the genetic contribution to the phenotypic correlation increased dramatically (.37,.47,.76), with a corresponding decrease in the comorbid influence of shared environment (.61,.44,.35). We conclude that for low ability, as well as for normal variation in ability, genetic "g" emerges during early childhood but is not fully developed until middle childhood.

A Longitudinal Genetic Analysis of Low Verbal and Nonverbal Cognitive Abilities in Early Childhood

By middle childhood, the same genetic factors are largely responsible for individual differences in verbal and nonverbal abilities, suggesting a genetic basis for general cognitive ability (“g”). Our previous work on verbal and nonverbal abilities throughout the normal range of variation during infancy and early childhood suggests that genetic influences show domain-specific as well as domain-general effects, implying that the switch to nearly complete domain-general effects occurs later in development. Much less is known about the genetic structure of low cognitive performance, although our previous work has shown that a composite measure of low “g” is highly heritable at 2, 3 and 4 years of age. We report the first multivariate, longitudinal analyses of low verbal and nonverbal cognitive abilities (defined as the lowest 10% of the distribution) at 2, 3 and 4 years of age using data from 9026 pairs of UK twins assessed by their parents as part of the Twins Early Development Study (TEDS). Domain-general genetic influences increased significantly from 2 to 3 to 4 years. Although the phenotypic polychoric correlation between low verbal and low nonverbal ability was similar at 2, 3 and 4 years (.36, .43, .35), the genetic contribution to the phenotypic correlation increased dramatically (.37, .47, .76), with a corresponding decrease in the comorbid influence of shared environment (.61, .44, .35). We conclude that for low ability, as well as for normal variation in ability, genetic “g” emerges during early childhood but is not fully developed until middle childhood.

Twins and Non-twin Siblings: Different Estimates of Shared Environmental Influence in Early Childhood

Twin studies typically indicate shared environmental influence for cognitive abilities, especially in early childhood. However, across studies, DZ twin correlations tend to be greater than non-twin sibling correlations, suggesting that twin estimates of shared environment are to some extent specific to twins. We tested this hypothesis in a sample of more than 1800 MZ and 1800 same-sex DZ pairs from the Twins Early Development Study (TEDS), a study of twins born in England and Wales in 1994 and 1995. For this analysis, we obtained comparable data from more than 130 same-sex younger siblings of the twins. Twins and their younger siblings were assessed for language, cognitive abilities and behavior problems by their parents at 2 and 3 years of age. For language and cognitive measures at both 2 and 3 years, but not for behavior problems, estimates of shared environment were more than twice as large for twins as compared to non-twin siblings. We conclude that about half of twin study estimates of shared environment for cognitive abilities in early childhood are specific to twins. Although many possibilities exist for explaining the special shared environment effect for twins, we suggest that cognitive-relevant experiences that are not shared by siblings are shared by twins because they are exactly the same age.

The Aetiology of High Cognitive Ability in Early Childhood

Both the environment and genetics are likely to influence the development of cognitive talent during the preschool years. It is not known to what degree or how these influences differ from those throughout the range of ability. 1943 twin pairs were assessed at 2, 3 and 4 years of age using diverse verbal and nonverbal cognitive measures. Consistently high scoring children were selected on a general cognitive factor. From behavioural genetic model fitting analyses, substantial shared environmental (70%) and modest genetic influences (20%) were found in the high group and this matched the aetiology of the entire sample. Strong genetic predisposition was not apparent. Individual differences in cognitive ability and high ability is largely due to shared environment during the preschool years.

The validity of parent‐based assessment of the cognitive abilities of 2‐year‐olds

Parent reports have been widely used to assess child behaviours in the socio‐emotional domain, but seldom have been used to assess behaviours within the cognitive domain. The present study examines the ability of parent reports and parent‐administered tasks obtained through the post to assess non‐verbal cognitive abilities in early childhood. In a sample of 107 2‐year‐olds, age‐corrected scores on parent reports and parent‐administered tasks assessing non‐verbal reasoning significantly predicted performance on the Mental Development Index (MDI) of the Bayley Scales of Infant Development‐II two weeks later (r = .49 and r = .41, p &lt; .0001, respectively). The multiple correlation between the two components and the MDI was .55 (p &lt; .0001). This ability of parental assessments to predict the MDI is comparable to the predictive power of standard tester‐administered measures at this age, even though the parent measure specifically excludes verbal items that are included in the MDI. Adding parent reports of language development significantly improved the prediction of the MDI (R = .66, p &lt; .0001). In addition, higher within‐domain than cross‐domain correlations reflect a significant ability of parents to discriminate verbal and nonverbal abilities.

A parent-offspring adoption study of cognitive abilities in early childhood

Do cognitive abilities in early childhood relate genetically and/or environmentally to isomorphic abilities in adulthood? Are specific cognitive abilities diffentiated in early childhood in terms of their prediction of adult cognitive abilities? The present study, the first behavioral genetic analysis of specific cognitive abilities in early childhood, explored these questions using parent-offspring data for 186 adopted children and 151 nonadopted children tested in the longitudinal Colorado Adoption Project at 3 years of age and 162 adopted children and 138 nonadopted children tested at 4 years. The children's Stanford-Binet IQ and scores for four specific cognitive abilities (verbal, spatial, perceptual speed, and memory) were correlated with corresponding measures for their parents—the biological and adoptive parents of the adopted children and the natural parents of the nonadopted children. Significant correlations were found between biological mothers' IQ and the IQ of their adopted away offspring at 3 and 4 years of age, suggesting genetic influence for IQ. However, specific cognitive abilities yielded no significant correlations between biological mothers and their adopted-away offspring. These results suggest that substantial genetic continuity exists for IQ from early childhood to adulthood, but not for specific cognitive abilities.