The application of structural equation modeling to maternal ratings of twins' behavioral and emotional problems.

The application of structural equation modeling to twin data is used to assess the impact of genetic and environmental factors on children's behavioral and emotional functioning. The models are applied to the maternal ratings of behavior of a subsample of 515 monozygotic and 749 dizygotic juvenile twin pairs, ages 8 through 16 yrs, obtained through mailed questionnaires as part of the Medical College of Virginia Adolescent Behavioral Development Twin Project. The importance of genetic, shared, and specific environmental factors for explaining variation is reported for both externalizing and internalizing behaviors, as well as significant differences in the causes of variation in externalizing behaviors among young boys and girls. The usefulness of applying structural equation models to data on monozygotic and dizygotic twins and the potential implications for addressing clinically relevant questions regarding the causes of psychopathology are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Rethinking environmental contributions to child and adolescent psychopathology: A meta-analysis of shared environmental influences.

Behavioral genetic research has concluded that the more important environmental influences result in differences between siblings (referred to as nonshared; e2), whereas environmental influences that create similarities between siblings (referred to as shared; c2) are indistinguishable from zero. However, there is mounting evidence that during childhood and adolescence, c2 may make important contributions to most forms of psychopathology. The aim of the meta-analysis was to empirically confirm this hypothesis. The author examined twin and adoption studies (n = 490) of internalizing and externalizing psychopathology prior to adulthood. Analyses revealed that c2 accounted for 10%–19% of the variance within conduct disorder, oppositional defiant disorder, anxiety, depression, and broad internalizing and externalizing disorders, regardless of their operationalization. When age, informant, and sex effects were considered, c2 generally ranged from 10%–30% of the variance. Importantly, c2 estimates did not vary across twin and adoption studies, suggesting that these estimates reflect actual environmental influences common to siblings. The only exception was attention-deficit/hyperactivity disorder, which appeared to be largely genetic (and particularly nonadditive genetic) in origin. Conceptual, methodological, and clinical implications of these findings are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Genetic and Environmental Mechanisms Underlying Stability and Change in Problem Behaviors at Ages 3, 7, 10, and 12.

Maternal ratings on internalizing (INT) and externalizing (EXT) behaviors were collected in a large, population-based longitudinal sample. The numbers of participating twin pairs at ages 3, 7, 10, and 12 were 5,602, 5,115, 2,956, and 1,481, respectively. Stability in both behaviors was accounted for by genetic and shared environmental influences. The genetic contribution to stability (INT: 43%; EXT: 60%) resulted from the fact that a subset of genes expressed at an earlier age was still active at the next time point. A common set of shared environmental factors operated at all ages (INT: 47%; EXT: 34%). The modest contribution of nonshared environmental factors (INT: 10%; EXT: 6%) could not be captured by a simple model. Significant age-specific influences were found for all components, indicating that genetic and environmental factors also contributed to changes in problem behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Posttraumatic stress disorder and the genetic structure of comorbidity.

This study used structural equation modeling to examine the genetic and environmental architecture of latent dimensions of internalizing and externalizing psychiatric comorbidity and explored structural associations between posttraumatic stress disorder (PTSD) and these dimensions. Data were drawn from the Vietnam Era Twin Registry and included lifetime diagnoses for PTSD and a range of other psychiatric disorders for 3,372 male–male twin pairs. Examination of the phenotypic structure of these disorders revealed that PTSD cross-loaded on both Internalizing and Externalizing common factors. Biometric analyses suggested largely distinct genetic risk factors for the latent internalizing and externalizing comorbidity dimensions, with the total heritability of the Externalizing factor (69%) estimated to be significantly stronger than that for Internalizing (41%). Nonshared environment explained the majority of the remaining variance in the Internalizing (58%) and Externalizing (20%) factors. Shared genetic variance across the 2 dimensions explained 67% of their phenotypic correlation (r = .52). These findings have implications for conceptualizations of the etiology of PTSD and its location in an empirically based nosology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Neighborhood disadvantage as a moderator of the association between harsh parenting and toddler-aged children's internalizing and externalizing problems.

Neighborhood dangerousness and belongingness were expected to moderate associations between harsh parenting and toddler-age children's problem behaviors. Fifty-five predominantly African American mothers participated with their 2-year old children. Neighborhood danger, neighborhood belongingness, and children's problem behaviors were measured with mothers' reports. Harsh parenting was measured with observer ratings. Analyses considered variance common to externalizing and internalizing problems, using a total problems score, and unique variance, by controlling for internalizing behavior when predicting externalizing behavior, and vice versa. Regarding the common variance, only the main effects of neighborhood danger and harsh parenting were significantly associated with total problem behavior. In contrast, after controlling for externalizing problems, the positive association between harsh parenting and unique variance in internalizing problems became stronger as neighborhood danger increased. No statistically significant associations emerged for the models predicting the unique variance in externalizing problems or models considering neighborhood belongingness. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Nonshared environmental mediation of the association between deviant peer affiliation and adolescent externalizing behaviors over time: Results from a cross-lagged monozygotic twin differences design.

It has been argued that peers are the most important agent of adolescent socialization and, more specifically, that this socialization process occurs at the child-specific (or nonshared environmental) level (J. R. Harris, 1998; R. Plomin & Asbury, 2005). The authors sought to empirically evaluate this nonshared environmental peer influence hypothesis by examining the association between externalizing behaviors and deviant peer affiliation in a sample of 454 pairs of monozygotic (genetically identical) twins, assessed at ages 14 and 17, within a cross-lagged twin differences design. Results argued against a causal nonshared environmental influence of peer affiliation on the development of externalizing behaviors and in favor of nonshared environmental “selection.” In particular, the twin with more externalizing behaviors at age 14 reported increased deviant peer affiliation relative to his or her co-twin 3 years later, regardless of his or her genetic predispositions toward externalizing behavior. Such findings suggest that adolescents with higher levels of externalizing behaviors select or shape (either intentionally or inadvertently) subsequent environmental experiences to involve increased affiliation with deviant peers. Implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

"Effects of chronic and acute cocaine treatment on the onset of maternal behavior and aggression in Sprague-Dawley rats": Correction.

Reports an error in the original article by J. M. Johns et al (Behavioral Neuroscience, 1994[Feb], Vol 108[1], 107–212). On page 108, in the Results, Maternal Behavior, the phrase in parentheses, "(8 min to crouch for 8 min or more of 30 min)' should read: "(6 min to crouch for 8 min or more of 30 min).' On page 109, the label on the upper right panel of Figure 1, "Percent That Crouch in 8 Minutes,' should read: "Percent That Crouch in 6 Minutes.' (The following abstract of this article originally appeared in record 1994-24731-001.) Pregnant rats (N?=?17) were treated either throughout gestation (Gestational Day 1–20) with 30 mg/kg per day (chronic cocaine) or with 1 15-mg/kg dose immediately following parturition (acute cocaine). Chronic and acute cocaine treatment delayed or diminished the postpartum onset of some components of maternal behavior, and chronically treated dams were significantly more aggressive toward a male intruder than acute cocaine-treated or saline-treated dams. Cocaine increased the latency to crouch over pups and decreased crouch duration during a 30-min observation period that immediately followed parturition. Latencies to nest build were also longer in more chronic cocaine-treated dams than in saline controls.… (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The role of specific emotions in children's responses to interparental conflict: A test of the model.

Mothers, fathers, and their 6-year-old children (N?=?164) participated in a study testing key tenets of the specific emotions model of marital conflict. Parents reported their marital conflict strategies, were observed interacting with their children, and rated children's behavioral adjustment. Children reported their emotional reactions to specific interparental conflicts. Results support the specific emotions model. Children's behaviors mirrored the marital or parental behaviors of same-gender parents. Indirect effects of marital aggression through parental behavior were detected, and marital and parental behaviors interacted to predict girls' externalizing. Girls' anger, sadness, and fear increased with fathers' marital aggression. Fear and the anger by fear interaction predicted girls' internalizing. Fathers' marital aggression interacted with anger to predict externalizing and interacted with fear to predict internalizing behavior in boys. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Trajectories of pure and co-occurring internalizing and externalizing problems from age 2 to age 12: Findings from the National Institute of Child Health and Human Development Study of Early Child Care.

How and why do internalizing and externalizing problems, psychopathological problems from different diagnostic classes representing separate forms of psychopathology, co-occur in children? We investigated the development of pure and co-occurring internalizing and externalizing problems from ages 2 to 12 with the use of latent class growth analysis. Furthermore, we examined how early childhood factors (temperament, cognitive functioning, maternal depression, and home environment) and early adolescent social and behavioral adjustment variables were related to differential trajectories of pure and co-occurring internalizing and externalizing problems. The sample (National Institute of Child Health and Human Development Study of Early Child Care) consisted of 1,232 children (52% male). Mother reports on the Child Behavior Checklist (Achenbach, 1991, 1992) were used to construct the trajectories of externalizing and internalizing problems. Analyses identified groups of children exhibiting pure and co-occurring internalizing and externalizing problems. Children exhibiting continuous externalizing or continuous co-occurring internalizing and externalizing problems across the 10-year period under investigation were more likely to (a) engage in risky behaviors, (b) be associated with deviant peers, (c) be rejected by peers, and (d) be asocial with peers at early adolescence. However, children exhibiting pure internalizing problems over time were only at higher risk for being asocial with peers as early adolescents. Moreover, the additive effects of individual and environmental early childhood risk factors influenced the development of chronic externalizing problems, although pure internalizing problems were uniquely influenced by maternal depression. Results also provided evidence for the concepts of equifinality and multifinality. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Environmental and genetic variance in children's observed and reported maladaptive behavior

The genetic and environmental contributions to children's maladaptive behavior are assessed in a sample of 154 twin pairs (77 MZ twin pairs and 77 DZ twin pairs), who range in age from 6 to 11 years. To bridge the strengths of behavioral genetic methods and environmental assessment techniques, we use a multimethod, multimeasure approach to data collection, and analyze the data using behavioral genetic modeling techniques. Results indicate that genetic variation accounts for a majority of the variance in parent-reported child maladaptive behavior (average = 62%). One parent-report measure also suggests a smaller, significant contribution of shared environmental variance. In contrast to the parental ratings, the observational coding and global impressions of parent-twin interactive behavior suggest that shared environment is the primary source of variance accounting for parent and child maladaptive behavior. This is due, in part, to the direct influence one's interactive partner has on the expression of maladaptive behavior in an interactive setting. When controlling for the co-participant's behavior, genetic variation increases and shared environmental variation decreases.     

Contributions of sibling relations to the adaptation of youths with insulin-dependent diabetes mellitus.

Associations among sibling relations and the psychosocial and illness-specific adaptation of youths (N?=?66) with insulin-dependent diabetes mellitus (IDDM) were examined. The findings suggest that sibling relations, especially sibling conflict, contribute an independent source of variance above and beyond that contributed by demographic characteristics, sibling constellation variables, and important dimensions of family relations in predicting the youths' adaptation. High family-life stress and high sibling status/power contributed unique variance in predicting internalizing behaviors, and male gender and sibling conflict contributed independently to externalizing problems. Sibling conflict also contributed unique variance to the youths' general self-esteem, along with social class and family cohesion, and to their adjustment to IDDM. Data suggest that parent–child dyads and sibling dyads represent interrelated and independent subsystems within the family, and that both subsystems may influence the psychosocial functioning of youths with IDDM. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Patterns of marital conflict predict children's internalizing and externalizing behaviors.

Reports the results of a longitudinal study on how marital interaction affects children. Observational assessment of marital interaction during conflict resolution obtained when children were 5 yrs old predicted teachers' ratings of internalizing and externalizing behaviors when the children were 8 yrs old. Two distinct and uncorrelated marital interaction patterns were related to specific forms of child outcomes. The Mutually Hostile pattern, which correlated with later marital dissolution, also predicted externalizing behavior patterns in children 3 yrs later. The Husband Angry and Withdrawn pattern predicted child internalizing behaviors. Marital satisfaction and child temperament did not relate to child outcomes, nor did they interact with marital patterns to produce deficits in child adjustment. Findings suggest that the specific behaviors couples use when resolving marital disputes may contribute differentially to the presence of externalizing and internalizing behavior patterns in children. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Latent curve modeling of internalizing behaviors and interpersonal skills through elementary school.

The trajectories of internalizing and interpersonal behaviors from kindergarten through fifth grade were studied using univariate and bivariate latent curve models. Internalizing behaviors demonstrated a small, yet statistically significant, linear increase over time, while interpersonal behaviors showed a small, yet statistically significant, linear decrease. There were individual differences in trajectories, and predictor variables accounted for some of this variation. In kindergarten, girls had more interpersonal behaviors than did boys. Children from higher SES families or with higher initial levels of externalizing behaviors had more internalizing behaviors and fewer interpersonal skills. One key finding from this study was that interpersonal and internalizing trajectories demonstrated a strong association. Increasing internalizing slopes were associated with decreasing interpersonal slopes. Establishing this empirical relation is necessary for understanding the developmental trajectory of these related behaviors, as well as important individual differences over time. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Relations among mothers' expressivity, children's effortful control, and their problem behaviors: A four-year longitudinal study.

Longitudinal relations between mothers' expressivity, children's effortful control, and their problem behaviors were examined when children (N = 181) were 6.5-10 years old (T2) and again 2 (T3) and 4 (T4) years later. Mothers reported on their expression of positive and negative dominant emotion. Mothers and teachers reported on children's effortful control and externalizing and internalizing problem behaviors. In structural equation models, variables exhibited consistency over time. Further, the relation between mothers' expressivity (positive minus negative dominant emotion) at T2 and children's externalizing problems at T4 was mediated by T3 effortful control. The same process of mediation was significant for teacher- but not mother-reported internalizing problems. The results provide one explanation for how emotion-related socializing behaviors influence children's problem behaviors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

When girls versus boys play alone: Nonsocial play and adjustment in kindergarten.

The goal of the present study was to examine the relations between different forms of children's nonsocial play behaviors and adjustment in kindergarten. The participants in this study were 77 kindergarten children (38 boys, 39 girls; mean age?=?66.16 months, SD?=?4.11 months). Mothers completed ratings of child shyness and emotion dysregulation. Children's nonsocial play behaviors (reticent, solitary-passive, solitary-active) were observed during free play. In addition, teachers rated child behavior problems (internalizing and externalizing) and social competence; academic achievement was assessed through child interviews. Results from regression analyses revealed that different types of nonsocial play were differentially associated with child characteristics and indices of adjustment. For some forms of nonsocial play, the nature of these associations differed significantly for boys and girls. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The power of friendship: Protection against an escalating cycle of peer victimization.

This study examined 2 aspects of friendship (presence and perceived qualities of a best friend) as moderators of behavioral antecedents and outcomes of peer victimization. A total of 393 children (188 boys and 205 girls) in the 4th and 5th grades (mean age 10 years 7 months) participated during each of 2 waves of data collection in this 1-year longitudinal study. Results indicated that teacher-reported internalizing and externalizing behaviors predicted increases in peer-reported victimization, but the relation of internalizing behaviors to increases in victimization was attenuated for children with a protective friendship. Victimization predicted increases in internalizing and externalizing behaviors but only for children without a mutual best friendship. Results highlight the importance of peer friendships in preventing an escalating cycle of peer abuse. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Marital Adjustment, Child-Rearing Disagreements, and Overreactive Parenting: Predicting Child Behavior Problems.

Using structural equation modeling, the authors evaluated the hypothesis that the relation between marital adjustment and children's behavior problems is mediated by child-rearing disagreements, whose effects are mediated by parents' overreactive discipline. In a community sample, fully or partially mediated models of internalizing and externalizing behavior problems of 3- to 7-year-old boys (N = 99) and girls (N = 104) were supported for mothers and fathers in 7 of 8 cases. Child-rearing disagreements always mediated the relation of marital adjustment and child behavior problems, and overreactive discipline was a final mediator in 3 cases. More variance was accounted for in mothers' than fathers' ratings. For mothers' ratings, the most variance was accounted for in boys' externalizing and girls' internalizing behavior problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Modeling genetic and environmental influences in the etiology of conduct disorder: A study of 2,682 adult twin pairs.

The etiology of conduct disorder (CD) was examined retrospectively in a sample of 2,682 male, female, and unlike-sex adult twin pairs from the community-based Australian Twin Register. Model-fitting analyses indicated a substantial genetic influence on risk for CD, accounting for 71% of the variance (95% confidence interval [CI]?=?32–79%). There was not a statistically significant effect of the shared environment in the best-fitting model of CD, but a modest effect of the shared environment on the risk for CD could not be rejected (95% CI?=?0-32%). The magnitude of genetic and environmental influences for CD liability did not vary significantly for boys and girls, and the specific genetic and environmental mechanisms important for the development of CD appeared to be largely the same for both sexes. The fit of a multiple-threshold model raises the possibility that CD may not necessarily be a discrete entity but rather an extreme of the normal variation in conduct-disordered behavior found in the general population. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Longitudinal Pathways to Psychological Adjustment Among Black Youth Living in Single-Parent Households.

A 5-wave model linking family and maternal functioning to youth psychological adjustment was tested with 139 single-mother-headed African American families with young adolescents (mean age = 11 years at recruitment) living in the rural South. Structural equation modeling indicated that an accumulation of family risk factors at Wave 1 was linked with maternal psychological functioning at Wave 2, which forecast competence-promoting parenting practices at Wave 3. These parenting practices indirectly forecast youth externalizing and internalizing behaviors 2 years later at Wave 5, through youth self-regulation at Wave 4. The hypothesized model was retested, controlling for Wave 1 youth externalizing and internalizing behaviors. All paths remained significant, indicating that the model accounted for change in youth psychological adjustment across 4 years. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Parental depression and interparental conflict: Children and adolescents’ self-blame and coping responses.

The present study examined the role of children and adolescents’ perceptions of self-blame specific to interparental conflict and children and adolescents’ coping behaviors in the context of parental depression as predictors of internalizing and externalizing symptoms in a sample of 108 youth (age 9–15 years old) of parents with a history of depression. Higher levels of current depressive symptoms in parents were associated with higher levels of interparental conflict and higher levels of internalizing symptoms in children and adolescents, and interparental conflict was positively associated with both internalizing and externalizing symptoms in children/adolescents. Consistent across a series of multiple regression models, children and adolescents’ perceptions of self-blame and use of secondary control coping (acceptance, distraction, cognitive restructuring, positive thinking) were significant, independent predictors of both internalizing and externalizing symptoms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)