The joint development of physical and indirect aggression: Predictors of continuity and change during childhood

Age-of-onset or behavioral sub-types? A prospective comparison of two approaches to characterizing the heterogeneity within antisocial behavior

There are two common approaches to sub-typing the well-documented heterogeneity within antisocial behavior: age-of-onset (i.e., childhood-onset versus adolescence-onset; see Moffitt 1993) and behavioral (i.e., physical aggression versus non-aggressive rule-breaking). These approaches appear to be associated, such that aggression is more characteristic of childhood-onset antisocial behavior whereas rule-breaking is linked to both child- and adolescence-onset antisocial behavior. However, it remains unclear which approach, if either, better explains the heterogeneity within antisocial behavior. We examined this question in a prospective sample of male twins, assessed at the ages of 11, 14, 17, and 24 years. Although the age-of-onset subtypes predicted adult antisocial behavior in the expected direction when analyzed alone, this association dissipated once we controlled for aggression and rule-breaking. Such findings suggest that the behavioral sub-types of antisocial behavior may be a stronger predictor of later antisocial outcomes than is its age-of-onset.

Joint trajectories for social and physical aggression as predictors of adolescent maladjustment: internalizing symptoms, rule-breaking behaviors, and borderline and narcissistic personality features

This investigation examined the relation between developmental trajectories jointly estimated for social and physical aggression and adjustment problems at age 14. Teachers provided ratings of children's social and physical aggression in Grades 3, 4, 5, 6, and 7 for a sample of 255 children (131 girls, 21% African American, 52% European American, 21% Mexican American). Participants, parents, and teachers completed measures of the adolescent's adjustment to assess internalizing symptoms, rule-breaking behaviors, and borderline and narcissistic personality features. Results showed that membership in a high and rising trajectory group predicted rule-breaking behaviors and borderline personality features. Membership in a high desister group predicted internalizing symptoms, rule-breaking behaviors, and borderline and narcissistic personality features. The findings suggest that although low levels of social and physical aggression may not bode poorly for adjustment, individuals engaging in high levels of social and physical aggression in middle childhood may be at greatest risk for adolescent psychopathology, whether they increase or desist in their aggression through early adolescence.

[Emotion regulation strategies and aggressive behavior of preschool children]

The present study (N = 193) examined use of emotional regulation strategies in physically and relationally aggressive preschool children (mean age: 55 months), compared to non-aggressive peers. To assess emotion regulation, we conducted a structured videotaped behavioral observation of a situation where frustration was elicited. Afterwards, regulation strategies were analyzed in seven categories. Physical and relational aggression was rated by preschool teachers. Cut-off scores were used to classify children as relationally or physically aggressive. Results show that physically aggressive children focused their attention on frustrating stimulus and used venting and cognitive verbalization more often than non-physically aggressive children. Relationally aggressive children used venting more often than non-relationally aggressive children. Findings suggest that aggressive children would benefit from training in emotion regulation.

Child and context characteristics in trajectories of physical and relational victimization among early elementary school children

Transactional models suggest that peer victimization results from both individual and context differences, and understanding these differences may point to important targets for prevention and interventions that reduce victimization. Multilevel modeling was used to examine within-person (aggression and emotional dysregulation), between-person (sex and age), and between-school (participation in a victimization prevention program) factors that influence changes in physical and relational victimization over the first three years of elementary school. Children (n = 423) reported their experiences of peer victimization at entry into Grade 1 and at the end of Grade 1, Grade 2, and Grade 3. On average, trajectories of both physical and relational victimization declined. However, for individual children, teacher-rated aggression was associated with increases in physical and relational victimization, while emotional dysregulation was associated with attenuation of longitudinal declines in physical victimization and increases in relational victimization. Individual differences in sex and age at entry into Grade 1 did not significantly influence victimization trajectories over Grades 1 to 3. Children who participated in the WITS® victimization prevention program showed significant declines in physical and relational victimization. Levels of victimization among nonparticipants remained stable. Implications of child and context characteristics for preventing peer victimization in elementary school are discussed.

Interactive links between theory of mind, peer victimization, and reactive and proactive aggression

This study investigated the relation between theory of mind and reactive and proactive aggression, respectively, as well as the moderating role of peer victimization in this context. The 574 participants were drawn from a longitudinal study of twins. Theory of mind was assessed before school entry, when participants were 5 years old. Reactive and proactive aggression as well as peer victimization were assessed a year later in kindergarten. Results from multilevel regression analyses revealed that low theory of mind was related to a high level of reactive aggression, but only in children who experienced average to high levels of peer victimization. In contrast, a high theory of mind was related to a high level of proactive aggression. Again, this relation was especially pronounced in children who experienced high levels of peer victimization. These findings challenge the social skills deficit view of aggression and provide support for a multidimensional perspective of aggressive behavior.

Predicting nonresponse to juvenile drug court interventions

Using data from a recent randomized clinical trial involving juvenile drug court (JDC), youth marijuana use trajectories and the predictors of treatment nonresponse were examined. Participants were 118 juvenile offenders meeting diagnostic criteria for substance use disorders assigned to JDC and their families. Urine drug screen results were gathered from weekly court visits for 6 months, and youth reported their marijuana use over 12 months. Semiparametric mixture modeling jointly estimated and classified trajectories of both marijuana use indices. Youth were classified into responder versus nonresponder trajectory groups based on both outcomes. Regression analyses examined pretreatment individual, family, and extrafamilial predictors of nonresponse. Results indicated that youth whose caregivers reported illegal drug use pretreatment were almost 10 times as likely to be classified into the nonresponder trajectory group. No other variable significantly distinguished drug use trajectory groups. Findings have implications for the design of interventions to improve JDC outcomes.

Sex differences in relational and overt aggression in the late elementary school years

Sex differences in relational and overt aggression among 3rd (n=176), 4th (n=179), and 5th graders (n=145) from three public schools (n=500; 278 girls) were examined. Nominations of relational aggression increased over time among 4th and 5th grade girls, but not among boys or 3rd grade girls. Among 3rd graders, boys received more nominations for relational aggression than girls. By the end of the 5th grade, girls received more relational aggression nominations than boys. There was also a significant rise in nominations of overt aggression among 5th grade girls, but not among 5th grade boys or younger boys and girls. As expected, boys were more likely than girls to be nominated for overt aggression at all grade levels. The findings are helpful for explaining inconsistencies of earlier research pertaining to sex differences in relational aggression and for advancing our understanding of the causes of aggression.

Brain serotonin synthesis in adult males characterized by physical aggression during childhood: a 21-year longitudinal study

BACKGROUND

Adults exhibiting severe impulsive and aggressive behaviors have multiple indices of low serotonin (5-HT) neurotransmission. It remains unclear though whether low 5-HT mediates the behavior or instead reflects a pre-existing vulnerability trait.

METHODOLOGY/PRINCIPAL FINDINGS

In the present study, positron emission tomography with the tracer alpha-[(11)C]methyl-L-tryptophan ((11)C-AMT) was used to compare 5-HT synthesis capacity in two groups of adult males from a 21-year longitudinal study (mean age +/- SD: 27.1+/-0.7): individuals with a history of childhood-limited high physical aggression (C-LHPA; N = 8) and individuals with normal (low) patterns of physical aggression (LPA; N = 18). The C-LHPA males had significantly lower trapping of (11)C-AMT bilaterally in the orbitofrontal cortex and self-reported more impulsiveness. Despite this, in adulthood there were no group differences in plasma tryptophan levels, genotyping, aggression, emotional intelligence, working memory, computerized measures of impulsivity, psychosocial functioning/adjustment, and personal and family history of mood and substance abuse disorders.

CONCLUSIONS/SIGNIFICANCE

These results force a re-examination of the low 5-HT hypothesis as central in the biology of violence. They suggest that low 5-HT does not mediate current behavior and should be considered a vulnerability factor for impulsive-aggressive behavior that may or may not be expressed depending on other biological factors, experience, and environmental support during development.

Developmental origins of disruptive behaviour problems: the 'original sin' hypothesis, epigenetics and their consequences for prevention

This paper reviews publications on developmental trajectories of disruptive behaviour (DB) problems (aggression, opposition-defiance, rule breaking, and stealing-vandalism) over the past decade. Prior to these studies two theoretical models had strongly influenced research on DB: social learning and disease onset. According to these developmental perspectives, children learn DB from their environment and onset of the disease is triggered by accumulated exposition to disruptive models in the environment, including the media. Most of the evidence came from studies of school age children and adolescents. Longitudinal studies tracing developmental trajectories of DB from early childhood onwards suggest an inversed developmental process. DB are universal during early childhood. With age, children learn socially acceptable behaviours from interactions with their environment. A 'disease' status is given to children who fail to learn the socially acceptable behaviours. The mechanisms that lead to deficits in using socially accepted behaviours are strongly intergenerational, based on complex genetic and environmental contributions, including epigenetic mechanisms. Prevention of these deficits requires early, intensive and long-term support to parents and child. Newly discovered epigenetic mechanisms suggest that intensive perinatal interventions will have impacts on numerous aspects of physical and mental health, including DB. This review also concludes that: a) subtypes of disruptive behaviours should not be aggregated because they have different developmental trajectories and require specific corrective interventions; b) the overt-covert and destructive-nondestructive dimensions appear the most useful to create DB subtypes; c) overt DB onset before covert DB because the latter require more brain maturation; d) DB subtype taxonomies are more useful for clinicians than developmental taxonomies because the latter are post mortem diagnoses and clinicians' retrospective information is unreliable; e) we need large-scale collaborative preventive experimental interventions starting during early pregnancy to advance knowledge on causes and prevention of DB problems.

Associations between Sadness and Anger Regulation Coping, Emotional Expression, and Physical and Relational Aggression among Urban Adolescents

This study examined associations between self reports of sadness and anger regulation coping, reluctance to express emotion, and physical and relational aggression among two cohorts of predominantly African-American fifth (N = 191; 93 boys and 98 girls) and eighth (N = 167; 73 boys and 94 girls) graders. Multiple regression analyses indicated unique associations between relational aggression and expressive reluctance and sadness regulation coping. In contrast, physical aggression, but not relational aggression, was associated with anger regulation coping. These relations did not differ across gender, but, the strength of the association between anger regulation coping and physical aggression varied by grade. Sadness regulation coping moderated the association between expressive reluctance and relational aggression. Conversely, anger regulation coping moderated the relation between expressive reluctance and physical aggression, however, the strength of this relation differed by gender. These findings have important implications for intervention efforts.

Parenting-by-gender interactions in child psychopathology: attempting to address inconsistencies with a Canadian national database

BACKGROUND

Research has shown strong links between parenting and child psychopathology. The moderating role of child gender is of particular interest, due to gender differences in socialization history and in the prevalence of psychiatric disorders. Currently there is little agreement on how gender moderates the relationship between parenting and child psychopathology. This study attempts to address this lack of consensus by drawing upon two theories (self-salience vs. gender stereotyped misbehaviour) to determine how child gender moderates the role of parenting, if at all.

METHODS

Using generalized estimating equations (GEE) associations between three parenting dimensions (hostile-ineffective parenting, parental consistency, and positive interaction) were examined in relationship to child externalizing (physical aggression, indirect aggression, and hyperactivity-inattention) and internalizing (emotional disorder-anxiety) dimensions of psychopathology. A sample 4 and 5 year olds from the National Longitudinal Survey of Children and Youth (NLSCY) were selected for analysis and followed over 6 years (N = 1214). Two models with main effects (Model 1) and main effects plus interactions (Model 2) were tested.

RESULTS

No child gender-by-parenting interactions were observed for child physical aggression and indirect aggression. The association between hostile-ineffective parenting and child hyperactivity was stronger for girls, though this effect did not reach conventional levels of statistical significance (p = .059). The associations between parenting and child emotional disorder did vary as a function of gender, where influences of parental consistency and positive interaction were stronger for boys.

DISCUSSION

Despite the presence of a few significant interaction effects, hypotheses were not supported for either theory (i.e. self-salience or gender stereotyped misbehaviour). We believe that the inconsistencies in the literature regarding child gender-by-parenting interactions is due to the reliance on gender as an indicator of a different variable which is intended to explain the interactions. This may be problematic because there is likely within-gender and between-sample variability in such constructs. Future research should consider measuring and modelling variables that are assumed to explain such interactions when conducting gender-by-parenting research.

Research Review: 'Ain't misbehavin': Towards a developmentally-specified nosology for preschool disruptive behavior

There is increasing consensus that disruptive behavior disorders and syndromes (DBDs) are identifiable in preschool children. There is also concomitant recognition of the limitations of the current DBD nosology for distinguishing disruptive behavior symptoms from the normative misbehavior of early childhood. In particular, there appears to be substantial insensitivity to heterotypic manifestations of this developmental period and problems in identifying meaningful heterogeneity. As a result, the developmental basis for much of the current nosology may be called into question. To address these and other critical issues, this paper reviews the foundational elements of clinical and developmental science pertinent to developmental differentiation of disruptive behavior in the preschool period as paradigmatic for developmental specification across the lifespan and generates an agenda for future research. We begin by reviewing evidence of the validity of DBDs in preschool children. This is followed by an outline of key developmental concepts and a review of the corollary evidence from developmental science. These provide a basis for conceptualizing disruptive behavior in reference to developmental deviation in four core dimensions hypothesized to mark the core features of disruptive behavior syndromes. Finally, we propose a program of research to establish an empirical basis for determining the incremental utility of a developmentally specified nosology. Central to this approach is a contention that the benefits of developmental specification are extensive and outweigh any disadvantages. This is because a developmentally specified approach holds substantial promise for increasing sensitivity and specificity for differentiating disruptive behavior from normative misbehavior and from other related syndromes as well as for improving prediction. Further, more precisely defined, developmentally based phenotypes are likely to elucidate distinct mechanisms within translational studies and to serve as a catalyst for the generation of novel treatments.

Predictors and sequelae of trajectories of physical aggression in school-age boys and girls

Teacher-rated trajectories of physical aggression in boys and girls from first through sixth grade were examined using data from the NICHD Study of Early Child Care and Youth Development. In separate analyses, four trajectories were identified in boys and three in girls. Higher levels of aggression in both boys and girls were related to greater sociodemographic risk and higher maternal harshness in the preschool years; lower levels of observed maternal sensitivity during early childhood also predicted higher trajectories of aggression among girls. Trajectory groups also differed on a range of social and academic adjustment outcomes in sixth grade, with the most aggressive children and even moderately aggressive children evidencing some difficulties in adjustment. Patterns and levels of aggression in boys and girls are discussed as are their predictors and consequences.

Modeling dad: animal models of paternal behavior

In humans, paternal behaviors have a strong influence on the emotional and social development of children. Fathers, more frequently than mothers, leave the family nucleus, and/or become abusive, leading to offspring that are more likely to grow under stressful conditions and greater susceptibility to abnormal health and social outcomes. Literature on parental behaviors, human or animal, has primarily focused on the interactions between mothers and offspring, with little research directed at understanding paternal behavior. In animal studies, experimenters correlate paternal behaviors with those seen in rodent or primate mothers, often under situations in which behaviors such as nest protection, huddling, pup grooming, and retrieval are artificially induced. In humans, the majority of the studies have looked at paralleling hormonal changes in fathers with those occurring in mothers, or observed paternal behaviors in populations with specific anthropological backgrounds. These studies reveal commonalities in parental behaviors and their underlying neural circuits. However, this work highlights the possibility that paternal behavior has components that are strictly masculine with unique neurobiological mechanisms. This review summarizes this information and provides a current view of a topic that needs further exploration.

Continuity and change in social and physical aggression from middle childhood through early adolescence

For a sample followed from age 9-13 (N=281), this investigation examined developmental trajectories for social and physical aggression as measured by teacher ratings. Trajectories for both forms of aggression were estimated first separately, then jointly. Mean levels of both social and physical aggression decreased over time for the overall sample, but with high variability of individual trajectories. Subgroups followed high trajectories for both social and physical aggression. Joint estimation yielded six trajectories: low stable, low increasers, medium increasers, medium desisters, high desisters, and high increasers. Membership in the high increaser group was predicted by male gender, unmarried parents, African American ethnicity, and maternal authoritarian and permissive parenting. Permissive parenting also predicted membership in the medium increaser group. This is one of the first studies to examine social aggression longitudinally across this developmental period. Though the results challenge the claim that social aggression is at its peak in early adolescence, the findings emphasize the importance of considering different developmental trajectories in trying to understand origins and outcomes of aggression.

Developmental links between trajectories of physical violence, vandalism, theft, and alcohol-drug use from childhood to adolescence

Differences in developmental trajectories of physical violence, vandalism, theft, and alcohol-drug use from ages 10 to 15 were studied. For females and for males, three trajectories of theft and of alcohol-drug use increased from 10 years to 15 years, while only the high trajectory of vandalism increased from ten to 14. All trajectories of physical violence decreased. Children who engaged in the high trajectories of vandalism, theft, and alcohol-drug use had a high probability of also being high in physical violence. Compared to males, females were less likely to be on the high trajectory of physical violence, and their trajectories of other antisocial behaviors were less strongly associated with high levels of physical violence. The results suggest that physical violence during pre-adolescence and adolescence has a different developmental pattern than other forms of antisocial behavior, and that its relation to these other forms of antisocial behavior differs by sex.

Research review: a critical review of studies on the developmental trajectories of antisocial behavior in females

BACKGROUND

Knowledge on the onset and the development of antisocial behavior in females is limited, because most of the research in this domain is based on males.

METHODS

We critically reviewed 46 empirical studies that examined developmental trajectories of antisocial behavior in females, notably to help determine whether or not an early-onset/life-course-persistent trajectory exists in females.

RESULTS

The review suggested that antisocial behavior in females can follow different developmental trajectories (e.g., early-onset/life-course-persistent, childhood-limited, adolescence-limited, adolescence-delayed-onset, adulthood-onset). However, many of the studies reviewed were limited by factors such as the use of global measures of antisocial behavior, the identification of the trajectories based on threshold criteria, and the small sample sizes.

CONCLUSIONS

Future studies should take into account the shortcomings highlighted in this review. Such studies are needed to improve the understanding and prevention of the development of antisocial behavior in females.

Family correlates of children's social and physical aggression with peers: Negative interparental conflict strategies and parenting styles

This investigation examines whether negative interparental conflict strategies (stonewalling, triangulation, verbal aggression, and physical aggression) and parenting styles are related to social and physical aggression with peers for children followed longitudinally from age 9 to 10 (N = 256). Parents reported on negative conflict strategies and parenting styles at the beginning of the study and teachers rated children's social and physical aggression with peers when children were in the 3rd and 4th grades. Structural equation modeling demonstrated that, for girls, mothers' negative interparental conflict strategies were positively associated with both social and physical aggression with peers. Mothers' negative conflict strategies were not related to boys' social and physical aggression at school, fathers' negative conflict strategies were not related to aggression for either gender, and no relations emerged for parenting styles. These results offer partial support for a same-gender modeling hypothesis and suggest that girls' social and physical aggression at school may be related to watching mothers resolve marital disputes by engaging in triangulation, stonewalling, and verbal and physical aggression with partners.

Contingent responses of mothers and peers to indirect and direct aggression in preschool and school-aged children

The primary goal of the study was to determine whether mother and peer's responses to direct and indirect aggression would contribute to children's use of direct and indirect aggression. Using adaptations of the Direct and Indirect Aggression Scale, a multi-informant strategy, and a sample of disadvantaged families, data were collected from 296 mothers of children ages 4-11, 237 children ages 6-11, and 151 teachers of those children. Mothers and peers were reported to react more harshly in response to direct aggression compared with indirect aggression, and higher rates of direct aggression were associated with reduced popularity. These findings were seen as being consistent with the hypothesis that different forms of aggression result in differential responding by mothers and peers, as well as the notion that direct aggression is a higher cost option than indirect aggression. Results also replicated previous findings that boys tend to use physical aggression more than girls, but girls use indirect aggression more than boys. Finally, low IQ was correlated with higher direct aggression in girls but had no relation with aggression in boys.

Joint development of bullying and victimization in adolescence: relations to delinquency and self-harm

OBJECTIVE

To estimate trajectories of bullying and victimization in early to mid-adolescence, associations between the trajectories, and links with delinquency and self-harm.

METHOD

A total of 3,932 adolescents (50% boys) reported bullying (ages 14 to 16), victimization (ages 13 to 16), delinquency (age 16), and self-harm (age 16).

RESULTS

Two bullying trajectories (low/decreasing, high/increasing) and three victimization trajectories (low, high/decreasing, high/increasing) were identified. Over time, victimization increased the likelihood of involvement in bullying to a greater extent than bullying increased the likelihood of victimization. Boys and girls in the high/increasing bullying and the low or high/increasing victimization trajectories (i.e., the bullies and the bully-victims) were highest in mid-adolescent delinquency. Girls following the high/increasing bullying and high/increasing victimization trajectories (bully-victims) were the highest in mid-adolescent self-harm.

CONCLUSIONS

Youths who are victimized by their peers are at increased risk, in turn, of victimizing others. Sex-specific adjustment problems are associated with differing patterns of involvement in bullying and victimization among adolescents.

Controlling parenting and physical aggression during elementary school

The goal of the present study was to examine whether controlling parenting contributes to the problem of physical aggression. Developmental trajectories of children's physical aggression were modeled from yearly teachers' ratings, from ages 6 to 12. Multinomial logistic regressions (N = 1,508) served to identify risk factors that distinguish children who display different levels of physical aggression throughout grade school. Results revealed that being a boy and having a reactive temperament were important child predictors. Parental separation and an early onset of motherhood were also significant risk factors. Finally, mothers' controlling parenting increased the odds of following the highest trajectory of physical aggression, above and beyond the previous risk factors.