Bonamy R. Oliver

The impact of prenatal maternal risk, fearless temperament and early parenting on adolescent callous‐unemotional traits: A 14‐year longitudinal investigation.

OBJECTIVE Proposals have been submitted to the DSM-V for the addition of a callous-unemotional (CU) specifier for conduct problem (CP) youth (CP/CU). While the addition of such a diagnostic category may aid in the identification of homogeneous CP subtypes, evidence on risks for the development of CP/CU remains limited. The present study sought to examine the extent to which CP/CU in early adolescence could be differentiated by family- and child-based risks from pregnancy to age 4 years. METHOD Using data from approximately 7,000 mothers and their offspring (51% male) participating in the Avon Longitudinal Study of Parents and Children, the authors examined maternal prenatal risks (psychopathology, criminality, substance use), childs fearless temperament (age 2 years) and harsh and warm parenting (age 4 years) as predictors of CP and CU at age 13; then used follow-back analyses to explore pre- and early post-natal risks in more detail. RESULTS Maternal prenatal risks increased fearless temperament and CP and CU. Fearless temperament was also prospectively associated with higher levels of early adolescent CP and CU, above and beyond parenting and prenatal maternal risks. Follow-back analyses showed fearless temperament in boys manifested as lower response to punishment cues, while for girls this temperament was indexed by boldness toward novel situations and strangers, particularly for CP/CU youth. CONCLUSIONS The current findings suggest that (i) maternal prenatal risks and fearless temperament showed a dose-response relationship with CP and CU (i.e., higher clustering of risks tended to relate to both higher levels and the co-occurrence of CU with CP), and (ii) intervention programs that aim to improve behavioural outcomes may consider targeting specific temperamental features in both boys and girls.

Negative parental discipline, conduct problems and callous-unemotional traits: monozygotic twin differences study

BACKGROUND Negative parenting practices may be an environmental risk factor for subsequent conduct problems. Research on the association between parenting practices and callous-unemotional traits, a risk factor for conduct problems, has produced mixed findings. AIMS To investigate whether negative parental discipline is a non-shared environmental risk factor for the development of conduct problems and callous-unemotional traits. METHOD Longitudinal, multi-informant data from a community sample of twins were analysed using the monozygotic (MZ) twin differences design for 4508 twins (2254 twin pairs). RESULTS Within MZ twin pairs, the twin receiving more negative parental discipline at 7 years had more conduct problems (but not more callous-unemotional traits) at 12 years. CONCLUSIONS During the transition to early adolescence, negative parental discipline operates as a non-shared environmental risk factor for development of conduct problems, but not for the development of callous-unemotional traits.

Verbal and Nonverbal Predictors of Early Language Problems: An Analysis of Twins in Early Childhood Back to Infancy.

We investigated infant precursors of low language scores in early childhood. The sample included 373 probands in 130 monozygotic (MZ) and 109 same-sex dizygotic (DZ) twin pairs in which at least one member of the pair scored in the lowest 15th percentile of a control sample on a general language factor derived from tester-administered tests at 4 ; 6. From data at 2 ; 0, 3 ; 0 and 4 ; 0 the antecedents of poor language performance at 4 ; 6 for these probands were compared to 290 control children. As early as 2 ; 0, language measures substantially predicted low-language status at 4 ; 6, with predictions increasing at 3 ; 0 and 4 ; 0. Nonverbal cognitive development at 3 ; 0 and 4 ; 0 was nearly as predictive of low language at 4 ; 6 as were the language measures. Behaviour problems were also significant predictors of low language status although the associations were only about half as strong. Bivariate genetic analyses indicated that these predictions are mediated by both genetic and shared environmental links.

The validity of a parent-based assessment of cognitive abilities in three-year olds

The purpose of the present study was to validate a parent-based assessment of cognitive abilities of three-year-old children against a standard tester-administered measure. The cognitive abilities of 85 children (50 boys and 35 girls, members of 43 twin pairs) were assessed using a measure of non-verbal abilities called the Parent Report of Childrens Abilities for three-year-olds (PARCA3), a vocabulary checklist, and the McCarthy Scales of Childrens Abilities (McCarthy, 1972). Correlations indicated that both components of the PARCA3 (parent-report and parent-administered) were significantly associated with the McCarthy scales, as was the vocabulary measure. Most importantly, the PARCA3 and vocabulary measure in combination significantly and substantially predict the McCarthy General Cognitive Index (Total R =0.63). We conclude that the PARCA3, with the vocabulary measure, provides a valid, inexpensive, reliable measure of cognitive ability for very young children.

Testing cognitive abilities by telephone in a sample of 6- to 8-year-olds

Telephone-administered measures of cognitive ability have been shown to be efficient and cost-effective alternatives to in-person-based assessments. The current study examined the validity of a telephone-assessed measure of cognitive ability using a sample of fifty-two 6–8-year-old children. The telephone test was composed of verbal- as well as performance-based measures of cognitive ability. The telephone-assessed measure of general cognitive ability correlated r=.65 with in-person-assessed measures. After correction for range restriction, the correlation was r=.72. Thus, measures of cognitive ability administered by telephone appear to be feasible, even in elementary school-age children.

Social Cognition and Conduct Problems: A Developmental Approach

OBJECTIVE To estimate associations between trajectories of conduct problems and social-cognitive competences through childhood into early adolescence. METHOD A prospective population-based cohort, the Avon Longitudinal Study of Parents and Children (ALSPAC) recruited in the prenatal period (13,988 children alive at 12 months) formed the basis for the current study. Socio-emotional and pragmatic language competences were examined in relation to conduct problem development in a group of 6,047 children with no known autistic-spectrum disorders. Specifically, conduct problem trajectories (low, childhood-limited, adolescent-onset, and early-onset persistent) identified using maternal prospective reports (Strengths and Difficulties Questionnaire: ages 4 through 13 years) were contrasted. Demographic confounders, child verbal IQ and other psychopathologies were controlled. RESULTS In contrast to individuals with low conduct problem levels, all conduct problem groups presented with difficulties in both social-cognitive domains. Deficits among those with early-onset persistent conduct problems were particularly apparent: 40.6% of boys and 24.3% of girls with persistent conduct problems met impairment criteria for one or other social-cognitive domain. Associations remained robust after controlling for demographic confounders (maternal age at birth, low SES, maternal education), child verbal IQ, and internalizing and inattention symptoms. For boys, results indicated that overlaps with overactivity symptoms may contribute problems with pragmatic language; this was not the case for girls or for socio-emotional difficulties. CONCLUSIONS Findings have far-reaching implications for children with conduct problems, particularly those with early onset and persistent difficulties. Traditional parent training interventions are likely to be bolstered by strategies that help to develop the social competences of these children.

Comorbidity between verbal and non-verbal cognitive delays in 2-year-olds: a bivariate twin analysis.

The purpose of this paper is to investigate the genetic and environmental aetiology of the comorbidity between verbal delay and non-verbal delay in infancy. For more than 3000 pairs of 2-year-old twins born in England and Wales in 1994, we assessed verbal (vocabulary, V) and non-verbal (non-verbal, P) performance. V delay probands were selected who were in the lowest 5% of V; P delay probands from the lowest 5% of P. We assessed the comorbidity of delay both categorically, using twin cross-concordances, and dimensionally, by applying a bivariate extension of DeFries and Fulker (DF) group analysis. Both approaches are bidirectional, in that probands can be selected for either V delay (and analysed in relation to their co-twin’s P score) or P delay (analysed in relation to their co-twin’s V score). From a categorical perspective, twin cross-concordances indicated that comorbidity between V delay and P delay is substantially due to genetic factors whether probands are selected for V delay or for P delay. MZ and DZ cross-concordances were 24% and 8%, respectively, for probands selected for V delay and 27% and 6% for probands selected for P delay. From a dimensional perspective using bivariate DF analysis, selecting for V delay yielded high bivariate group heritability (0.59) and a genetic correlation of 1.0. In contrast, when selecting on P, DF analysis indicated lower bivariate group heritability (0.20) and only a modest genetic correlation with V assessed dimensionally (0.36). These results are discussed in terms of the difference between categorical and dimensional approaches to quantitative traits and the bidirectional nature of comorbidity. Such multivariate genetic results could lead to diagnostic systems that are based on causes rather than phenotypic descriptions of symptoms.

Predicting Literacy at Age 7 From Preliteracy at Age 4 A Longitudinal Genetic Analysis

Early literacy experience and preliteracy knowledge have been shown to predict later literacy outcomes. Using a representative sample of 3,052 same-sex twin pairs (6,104 children) in the United Kingdom, we explored phenotypic and etiological interrelationships among early literacy experience, preliteracy knowledge, and school-based literacy outcomes (reading and writing). Both literacy experience and preliteracy knowledge at age 4 significantly and independently predicted literacy at age 7. Both measures also showed genetic influence that significantly predicted literacy at age 7, although genetic mediation was stronger for preliteracy knowledge than for early literacy experience. However, for both measures, shared environmental factors explained most of the association with literacy at age 7.

Genetic Influences on Specific Versus Nonspecific Language Impairment in 4-Year-Old Twins

The present study addresses the distinction between specific (SLI) and nonspecific (NLI) language impairment at an etiological level by estimating the relative genetic and environmental contributions to language impairment in children with SLI and NLI. Drawing on a large longitudinal twin study, we tested a sample of 356 four-and-a-half-year-old children with low language ability and their twin partners at home on a range of language and nonverbal measures. For children whose language and nonverbal abilities were both low (NLI), genetic influence on language impairment was moderate and shared environmental influence was substantial. A similar pattern emerged for children whose language difficulties occurred in apparent isolation (SLI), although there was a trend for the genetic effects to be smaller for SLI than for NLI: Group heritability was .18 for SLI and .52 for NLI. Probandwise cross-concordances were suggestive of some genetic overlap between these two groups, but not with a subgroup of children with more severe cognitive delay.

Genetics of parenting: The power of the dark side.

Reviews of behavioral genetic studies note that “control” aspects of parenting yield low estimates of heritability, while “affective” aspects (parental feelings) yield moderate estimates. Research to date has not specifically considered whether positive and negative aspects of parenting—for both feelings and control—may explain these etiological distinctions. We addressed this issue using parent reports of parenting in a large twin sample in the United Kingdom, at ages 9 (N = 2,260 twin pairs), 12 (N = 3,850 twin pairs) and 14 (N = 2,293 twin pairs) years. Our findings supported previous work indicating that parental feelings show greater heritability (h2) than control (across all ages, mean h2 feelings = .42, control = .13). Of specific interest is our novel finding that for control as well as for feelings, the heritability for negative aspects of parenting was greater than for positive aspects (e.g., across all ages, mean h2 total negativity = .44; total positivity = .12). Results across the 3 ages using common pathway models for all scales further endorsed our hypotheses. Previous research has shown that children’s genetically driven characteristics elicit parenting; our pattern of our results suggests that what is critical is the “dark” side of these characteristics for eliciting negativity from parents, whether feelings toward the child or control strategies are considered. Improving understanding of how the environment is shaped by the dark side is important theoretically and, ultimately, for targeting intervention.