Associations between early efficiency in language processing and learning outcomes in children born full term and preterm: Similarities and differences

Associations between children’s early language processing efficiency and later language, literacy, and non-verbal outcomes shed light on the extent to which early information processing skills support later learning across domains. Examining whether the strengths of associations are similar in typically developing and at risk populations provides an additional lens into the varying routes to learning that children take across development. We compared patterns of associations between early language processing efficiency (accuracy and reaction time) in the looking-while-listening (LWL) task and school-relevant skills in children born full-term (FT) and preterm (PT). Participants (n=94, 49 FT, 45 PT) were assessed in the LWL task at 18 months (corrected for degree of prematurity in PT group) and on standardized tests of expressive language, pre-literacy (print knowledge and phonological awareness), and non-verbal IQ at 4 ½ years. Early language processing efficiency was associated with later language and pre-literacy outcomes (r2 change ranged from 19.8 to 7.1, p < 0.01) to a similar extent in PT and FT children, controlling for age at test and SES, suggesting similar mechanisms of learning in these domains for PT and FT children. However, birth group moderated the association between reaction time and non-verbal IQ (r2 change 4.5, p < 0.05), such that an association was found in the PT but not the FT group. This finding suggests that information processing skills reflected in efficiency of real-time language processing may be recruited to support learning in a broader range of domains in the PT compared to the FT group.

Interrogating the validity of cumulative indices of environmental and genetic risk for negative developmental outcomes

Indices of cumulative risk (CR) have long been used in developmental research to encode the number of risk factors a child or adolescent experiences that may impede optimal developmental outcomes. Initial contributions concentrated on indices of cumulative environmental risk; more recently, indices of cumulative genetic risk have been employed. In this article, regression analytic methods are proposed for interrogating strongly the validity of risk indices by testing optimality of compositing weights, enabling more informative modeling of effects of CR indices. Reanalyses of data from two studies are reported. One study involved 10 environmental risk factors predicting Verbal IQ in 215 four-year-old children. The second study included an index of genetic CR in a G×E interaction investigation of 281 target participants assessed at age 15 years and then again at age 31 years for observed hostility during videotaped interactions with close family relations. Principles to guide evaluation of results of statistical modeling are presented, and implications of results for research and theory are discussed. The ultimate goals of this paper are to develop stronger tests of conjectures involving CR indices and to promote methods for improving replicability of results across studies.

Effects of Pediatric Traumatic Brain Injury on Verbal IQ: A Systematic Review and Meta-Analysis

Objectives: To examine the effects of pediatric traumatic brain injury (TBI) on verbal IQ by severity and over time. Methods: A systematic review and subsequent meta-analysis of verbal IQ by TBI severity were conducted using a random effects model. Subgroup analysis included two epochs of time (e.g., <12 months postinjury and ≥12 months postinjury). Results: Nineteen articles met inclusion criteria after an extensive literature search in MEDLINE, PsycInfo, Embase, and CINAHL. Meta-analysis revealed negative effects of injury across severities for verbal IQ and at both time epochs except for mild TBI < 12 months postinjury. Statistical heterogeneity (i.e., between-study variability) stemmed from studies with inconsistent classification of mild TBI, small sample sizes, and in studies of mixed TBI severities, although not significant. Risk of bias on estimated effects was generally low (k = 15) except for studies with confounding bias (e.g., lack of group matching by socio-demographics; k = 2) and measurement bias (e.g., outdated measure at time of original study, translated measure; k = 2). Conclusions: Children with TBI demonstrate long-term impairment in verbal IQ, regardless of severity. Future studies are encouraged to include scores from subtests within verbal IQ (e.g., vocabulary, similarities, comprehension) in addition to functional language measures (e.g., narrative discourse, reading comprehension, verbal reasoning) to elucidate higher-level language difficulties experienced in this population.

Children’s autistic traits and peer relationships: do non-verbal IQ and externalizing problems play a role?

Background Children with autism have difficulties in understanding relationships, yet little is known about the levels of autistic traits with regard to peer relationships. This study examined the association between autistic traits and peer relationships. Additionally, we examined whether the expected negative association is more pronounced in children with a lower non-verbal IQ and in those who exhibit more externalizing problems. Method Data were collected in a large prospective birth cohort of the Generation R Study (Rotterdam, the Netherlands) for which nearly 10,000 pregnant mothers were recruited between 2002 and 2006. Follow up data collection is still currently ongoing. Information on peer relationships was collected with PEERS application, an interactive computerized task (M = 7.8 years). Autistic traits were assessed among general primary school children by using the Social Responsiveness Scale (M = 6.1 years). Information was available for 1580 children. Result Higher levels of autistic traits predicted lower peer acceptance and higher peer rejection. The interaction of autistic traits with externalizing problems (but not with non-verbal IQ or sex) was significant: only among children with low externalizing problems, a higher level of autistic traits predicted less peer acceptance and more peer rejection. Among children exhibiting high externalizing problems, a poor peer acceptance and high level of rejection is seen independently of the level of autistic traits. Conclusion We conclude that autistic traits—including traits that do not classify as severe enough for a clinical diagnosis—as well as externalizing problems negatively impact young children’s peer relationships. This suggests that children with these traits may benefit from careful monitoring and interventions focused at improving peer relationships.

Trajectories and perceptual precursors of intelligence in minimally verbal autistic children from preschool to school age

Background The question of cognitive prognosis is frequently asked at the time of autism diagnosis, often at preschool age. It remains however difficult to answer this question at such a young age, given the considerable heterogeneity of cognitive development trajectories and the challenges associated with intellectual assessment in autistic children, particularly among minimally verbal children. Methods The current prospective cohort study investigated whether early perceptual abilities measured at preschool age could predict later intellectual abilities at school age in a group of 41 autistic (9 girls, 32 boys) and 57 neurotypical children (29 girls, 28 boys). Participants were assessed at three time points during the childhood period (between the age of 2 and 8 years old) using the Wechsler Preschool and Primary Scales of Intelligence – Fourth edition as a measure of full-scale IQ and the Raven’s Colored Progressive Matrices as a measure of non-verbal IQ. The performance on two perceptual tests (Visual Search and Children Embedded Figures Test) as well as the frequency of perceptual behaviors served as predictors of later intellectual abilities. Results Early performance on perceptual tests measured at preschool age was positively related to later full-scale IQ in both autistic and neurotypical children. Furthermore, both perceptual behaviors and performance on perceptual tests measured at preschool age were associated with later non-verbal IQ in the autistic group. In contrast, only the performance on Children Embedded Figures Test was associated with later non-verbal IQ in the neurotypical group. Limitations: The sample size was relatively modest, with some attrition across time points, as expected in a sample including preschool minimally and non-verbal children. Conclusions Our findings support the important role of perception in autistic cognition. Early perceptual abilities may be a valid avenue for estimating general intelligence and non-verbal abilities at preschool age, particularly for minimally verbal autistic children.

Convergent Validity of a Quick Online Self-Administered Measure of Verbal IQ for Psychology Researchers

Verbal intelligence—which relates to memory performance, abstract reasoning, and g—is often important to account for within psychological research. However, the time demands and financial costs associated with researcher-administered testing using valid measures of intelligence limit researchers’ ability to include such measures within their research. To address this issue, we examined the convergent validity of two tests of verbal intelligence that could be self-administered online with the well-validated Wechsler Abbreviated Scale of Intelligence–Second Edition (WASI-II). An undergraduate sample of participants (N = 104) completed the Self-Administered Verbal IQ Test (SA-VIQT), with a subsection (n = 64) completing the Self-Administered Full Scale IQ Test (SA-FSIQT), both made available online by Open-Source Psychometrics Project. Additionally, all participants were administered the Verbal Comprehension Index (VCI) of WASI-II by a trained researcher, with a subsection administered the full WASI-II including the Perceptual Reasoning Index (PRI) (n = 72). Both online tests demonstrated convergent validity with the WASI-II. While the online tests may only deliver a crude indicator of verbal intelligence, they provide researchers the opportunity for statistical control or screening of participants across large samples in an efficient manner not possible when using researcher-administered testing methods.

Auditory Time Thresholds for Subsecond but not Suprasecond Stimuli are Impaired in ADHD

Background. The literature on time perception in individuals with ADHD is extensive but inconsistent, probably reflecting the use of different tasks and performances indexes. Methods. A sample of 40 children/adolescents (20 with ADHD, 20 neurotypical) was engaged in two identical psychophysical tasks measuring auditory time thresholds for both subsecond (0.5-1s) and suprasecond (0.75-3s) stimuli. Results. Results showed a severe impairment in ADHD for subsecond thresholds (Log10BF=1.9). The deficit remained strong even when non-verbal IQ was regressed out and correlation with age suggests a developmental delay. Suprasecond thresholds were indistinguishable between the two groups (Log10BF = –0.5) and not correlated with subsecond thresholds. Conclusions. Since much evidence suggest that perception of subsecond stimuli does not load on cognitive control and working memory, the current results are consistent with a pure timing deficit in individuals with ADHD.

Non-verbal IQ and change in restricted and repetitive behavior throughout childhood in autism: a longitudinal study using the Autism Diagnostic Interview-Revised

Background Restricted and repetitive behavior (RRB) is one of the characteristic features of Autism Spectrum Disorder. This domain of symptoms includes a broad range of behaviors. There is a need to study each behavior individually to better understand the role of each in the development of autistic children. Moreover, there are currently no longitudinal studies investigating change in these behaviors over development. Methods The goal of the present study was to explore the association between age and non-verbal IQ (NVIQ) on 15 RRB symptoms included in the Autism Diagnostic Interview-Revised (ADI-R) over time. A total of 205 children with ASD were assessed using the ADI-R at time of diagnosis, at age 6 years, and at age 11 years, and with the Wechsler Intelligence Scales for Children—Fourth Edition (WISC-IV) at age 8 years. Results The proportion of children showing each RRB tended to diminish with increasing age, except for sensitivity to noise and circumscribed interests, where the proportion increased over time. Although there was no significant main effect of NVIQ, there was a significant interaction between age and NVIQ. This was mainly driven by Difficulties with change in routine, for which higher NVIQ was associated with the behavior remaining relatively stable with age, while lower NVIQ was associated with the behavior becoming more prevalent with age. Limitations The study focused on the presence/absence of each RRB but did not account for potential changes in frequency or severity of the behaviors over development. Furthermore, some limitations are inherent to the measures used. The ADI-R relies on parent report and hence has some level of subjectivity, while the Wechsler intelligence scales can underestimate the intellectual abilities of some autistic children. Conclusions These results confirm that specific RRB are differentially linked to age and NVIQ. Studying RRB individually is a promising approach to better understanding how RRB change over the development of autistic children and are linked to other developmental domains.

Predicting persistence of hallucinations from childhood to adolescence

Summary Background Psychotic experiences predict adverse health outcomes, particularly if they are persistent. However, it is unclear what distinguishes persistent from transient psychotic experiences. Aims In a large population-based cohort, we aimed to (a) describe the course of hallucinatory experiences from childhood to adolescence, (b) compare characteristics of youth with persistent and remittent hallucinatory experiences, and (c) examine prediction models for persistence. Method Youth were assessed longitudinally for hallucinatory experiences at mean ages of 10 and 14 years (n = 3473). Multi-informant-rated mental health problems, stressful life events, self-esteem, non-verbal IQ and parental psychopathology were examined in relation to absent, persistent, remittent and incident hallucinatory experiences. We evaluated two prediction models for persistence with logistic regression and assessed discrimination using the area under the curve (AUC). Results The persistence rate of hallucinatory experiences was 20.5%. Adolescents with persistent hallucinatory experiences had higher baseline levels of hallucinatory experiences, emotional and behavioural problems, as well as lower self-esteem and non-verbal IQ scores than youth with remittent hallucinatory experiences. Although the prediction model for persistence versus absence of hallucinatory experiences demonstrated excellent discriminatory power (AUC-corrected = 0.80), the prediction model for persistence versus remittance demonstrated poor accuracy (AUC-corrected = 0.61). Conclusions This study provides support for the dynamic expression of childhood hallucinatory experiences and suggests increased neurodevelopmental vulnerability in youth with persistent hallucinatory experiences. Despite the inclusion of a wide array of psychosocial parameters, a prediction model discriminated poorly between youth with persistent versus remittent hallucinatory experiences, confirming that persistent hallucinatory experiences are a complex multifactorial trait.

Educational attainment and trajectories of cognitive decline during four decades—The Glostrup 1914 cohort

Background The potential association between level of education and age-related cognitive decline remains an open question, partly because of a lack of studies including large subsamples with low education and follow-up intervals covering a substantial part of the adult lifespan. Objectives To examine cognitive decline assessed by a comprehensive clinical test of intelligence over a 35-year period of follow-up from ages 50 to 85 and to analyze the effect of education on trajectories of cognitive decline, including the effects of selective attrition. Methods A longitudinal cohort study with a 35-year follow-up of community dwelling members of the Glostrup 1914 cohort. The study sample comprised 697 men and women at the 50-year baseline assessment and additional participants recruited at later follow-ups. Verbal, Performance, and Full Scale IQs were assessed using the Wechsler Adult Intelligence Scale at ages 50, 60, 70, 80, and 85. To be able to track cognitive changes between successive WAIS assessments, all IQs were based on the Danish 50-year norms. Information on school education was self-reported. The association between education and cognitive decline over time was examined in growth curve models. Selective attrition was investigated in subsamples of participants who dropped out at early or later follow-ups. Results The trajectories for Verbal, Performance, and Full Scale IQ showed higher initial cognitive performance, but also revealed steeper decline among participants with a formal school exam compared to participants without a formal exam. Verbal IQ showed the largest difference in level between the two educational groups, whereas the interaction between education and age was stronger for Performance IQ than for Verbal IQ. In spite of the difference in trajectories, higher mean IQ was observed among participants with a formal school exam compared to those without across all ages, including the 85-year follow-up. Further analyses revealed that early dropout was associated with steeper decline, but that this effect was unrelated to education. Conclusion Comprehensive cognitive assessment over a 35-year period suggests that higher education is associated with steeper decline in IQ, but also higher mean IQ at all follow-ups. These findings are unlikely to reflect regression towards the mean, other characteristics of the employed test battery or associations between educational level and study dropout.