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

Social Anxiety and Peer Victimization and Aggression: Examining Reciprocal Trait-State Effects among Early Adolescents

As peer relationships become paramount during early adolescence, there's a normative rise in social anxiety, coinciding with a peak in peer victimization and aggression. Although previous studies have suggested reciprocal associations between changes in social anxiety and adolescent peer victimization and aggression, the mechanics of these associations at the personal trait and time-varying state levels remains unclear. This study examined the longitudinal relations between social anxiety and adolescent peer victimization and aggression by disentangling between-person trait differences from within-person state processes. A total of 4731 Chinese early adolescents (44.9% girls; M age = 10.91 years, SD = 0.72) participated in a four-wave longitudinal study with 6-month intervals. Random-intercept cross-lagged panel model (RI-CLPM) was applied. The results revealed higher levels of social anxiety are associated with more peer victimization and aggression at the between-person trait level. At the within-person state level, adolescent social anxiety, and adolescent physical victimization and physical aggression, reciprocally predicted each other. Relational victimization significantly predicted an increase of social anxiety, but not vice versa. Social anxiety positively predicted relational aggression over time, whereas the effect of relational aggression on social anxiety was only observed at the initial stage of early adolescence. These findings highlight that various types of victimization and aggression might exhibit unique reciprocal associations with social anxiety. Distinguishing between the within-person state and between-person trait effects is crucial in research that informs the co-development of adolescent peer victimization, aggression, and social anxiety.

Self-esteem and cortical thickness correlate with aggression in healthy children: A surface-based analysis

Aggressive behavior can have serious physical, psychological, and social consequences. However, little is known about the personality and neurological antecedents underlying aggressive behavior in children. The objective of this study was to investigate the relationship between self-esteem, aggression, and brain structure (i.e., cortical thickness and surface area) in a population of healthy children (N = 78; 9-12 years; mean age: 9.95 ± 0.90 years). The results revealed that self-esteem showed a negative association with aggression and significantly predicted aggressive behavior. No gender differences were found in aggression and its neural correlates. We performed the cortical parcellation method to further explore the neural foundations underlying the association of self-esteem with aggression. Children with higher aggression had increased cortical thickness in four clusters after multiple comparison correction: right medial orbitofrontal cortex, right lateral orbitofrontal cortex, right superior frontal gyrus, and left insula. In a mediation analysis, cortical thickness in the right medial orbitofrontal cortex contributed to the effect of self-esteem on aggression. These findings extend our understanding of morphological correlates of aggression in children, suggesting that an increased cortical thickness in childhood is a potential mechanism linking low self-esteem to aggression.

Provoked and unprovoked aggression in toddlerhood: Evaluating measurement invariance and latent means across gender, age, and time

This paper re-examined the factor structure of a recently developed parent report of aggression, the Provoked and Unprovoked Aggression Questionnaire, and evaluated measurement invariance and latent mean differences across gender, age, and time. Participants were 333 mothers of toddlers (younger age group: n = 167, 53.9% boys, Mage Time 1  = 18.30 months, SD = 0.45; older age group: n = 166, 48.8% boys, Mage Time 1  = 24.29 months, SD = 0.38) who filled out provoked (eight items) and unprovoked (five items) aggression scales twice over a 3-month period. We found evidence for the configural, metric, and scalar measurement invariance-a requirement needed to make a meaningful comparison between aggression means across gender, age groups, and time. When comparing means for boys and girls, gender differences emerged earlier for unprovoked than provoked aggression. Also, the frequency of provoked aggression increased among younger, but not older, toddlers. By developing a brief parental report of aggression in toddlerhood, we hope to fill a void of early aggression measures that tap the contextual variability in aggressive behaviors, and thereby stimulate more research to further our understanding of different types of aggression and their correlates in toddlerhood.

Love withdrawal use by toddlers: Multi-informant associations with aggression and parents' use of love withdrawal

Love withdrawal is a form of interpersonal manipulation that shares many features with relational aggression; its use by children has not been examined. Guided by social learning theory, we sought to investigate the prevalence of toddlers' use of love withdrawal toward caregivers (parents and teachers) and further investigate how this behavior was associated with relational and physical aggression and parents' use of love withdrawal. These aims were examined using parent and teacher reports in a sample of 198 toddlers (Mage  = 33.62 months; SD = 5.00 months; 50.5% girls). We found that most toddlers used love withdrawal directed at parents (79.2%) and teachers (72.1%) when angry and displayed this type of behavior more than relational and physical aggression. Accounting for household income, hours per week in childcare, and child age in months, as well as classroom clustering, we found that relational aggression, and not physical aggression, predicted the use of love withdrawal by toddlers (teacher reports), and that the associations were stronger for love withdrawal and relational aggression than for physical aggression. We also found that parents' use of love withdrawal toward their child was correlated with their reports of their child's use of love withdrawal, but not with their child's use of aggression. These results highlight the importance of considering the use of love withdrawal by children given its association with aggression which is linked to poorer psychosocial functioning.

Heterotypic and homotypic continuity in psychopathology: a narrative review

Psychopathology is a process: it unfolds over time and involves several different factors. To extend our knowledge of such process, it is vital to understand the trajectories that lead to developing and maintaining a specific disorder. The construct of continuity appears very useful to this aim. It refers to the consistency, similarity, and predictability of behaviors or internal states across different developmental phases. This paper aims to present a narrative review of the literature on homotypic and heterotypic continuity of psychopathology across the lifespan. A detailed search of the published literature was conducted using the PsycINFO Record and Medline (PubMed) databases. Articles were included in the review based on the following criteria: (1) publication dates ranging from January 1970 to October 2022; and (2) articles being written in the English language. To ensure a thorough investigation, multiple combinations of keywords such as "continuity," "psychopathology," "infancy," "childhood," "adolescence," "adulthood," "homotypic," and "heterotypic" were used. Articles were excluded if exclusively focused on epidemiologic data and if not specifically addressing the topic of psychopathology continuity. The literature yielded a total of 36 longitudinal studies and an additional 190 articles, spanning the research published between 1970 and 2022. Studies on continuity focus on the etiology of different forms of mental disorders and may represent a fundamental resource from both a theoretical and clinical perspective. Enhancing our understanding of the different trajectories beneath psychopathology may allow clinicians to implement more effective strategies, focusing both on prevention and intervention. Since literature highlights the importance of early detection of clinical signs of psychopathology, future research should focus more on infancy and pre-scholar age.

Indirect aggression, anxiety, and empathy: Disaggregating between and within person longitudinal associations during childhood and adolescence

Although indirectly aggressive behavior and anxiety symptoms can co-occur, it is unclear whether anxiety is an antecedent or outcome of indirect aggression at the individual level and whether other personality traits can contribute to these longitudinal associations. Therefore, the between- and within-person associations among indirect aggression, anxiety symptoms, and empathic concern were examined across adolescence from ages 11 to 16 in a cohort of individuals followed annually (N = 700; 52.9% girls; 76.0% White) controlling for direct aggression and demographic variables. Results of autoregressive latent trajectory models with structured residuals supported an acting out model at the within-person level. Specifically, anxiety symptoms positively predicted indirect aggression and indirect aggression negatively predicted empathic concern at each adjacent time point. These findings suggest that methods of reducing worries about the self and increasing healthy self-confidence could prevent indirect aggression and help build concern and compassion toward others.

Early co-occurrence of peer victimization and aggression

An accelerated longitudinal research design was used to examine heterogeneity in the developmental co-occurrence of peer relational victimization and aggression and of peer overt victimization and aggression from age 4.5 to 10.5 years. Data were gathered from four cohorts of children in kindergarten to Grade 3 (N = 503) on six occasions across 2 years. Psychopathology, peer, and social-cognitive factors were examined as predictors of the joint trajectories. Sequential process latent growth mixture models identified four distinct subgroups for the relational trajectories (co-occurring increasing aggression, co-occurring increasing victimization, high chronic victimization, typical low risk) and four distinct subgroups for the overt trajectories (co-occurring decelerating aggression, high chronic victimization, moderate chronic victimization, typical low risk). Membership in the co-occurring trajectories was associated with psychopathology and membership in the chronic victimization trajectories was related to internalizing and social-cognitive problems but also peer likeability.

Psychometric properties of the Social Behavior Questionnaire (SBQ) in a longitudinal population-based sample

We assessed the psychometric properties of the Social Behavior Questionnaire (SBQ), a 30-item questionnaire evaluating social (e.g., disruptive behaviors, bullying) and emotional problems (e.g., anxiety, depression) among children aged 3.5–12 years. Children ( n = 1,950, 50.21% boys) were drawn from the Quebec Longitudinal Study of Child Development. Mothers reported the frequency with which children presented social and emotional behaviors from 3.5 to 8 years of age, and teachers from 6 to 12 years. We assessed internal structure using Confirmatory Factor Analysis, reliability using Cronbach’s alpha, and convergent and discriminant validity using a multitrait-multimethod (MTMM) approach. The six-factor (emotional distress, withdrawal, impulsive/hyperactive/inattentive, disruptive behaviors, prosocial behaviors, and peer relationships difficulties) structure of the SBQ showed good fit from ages 3.5 to 12 years. Reliability estimates were good to excellent (alphas > .7), and MTMM showed good convergent and discriminant validity. Overall, the SBQ presented good psychometric properties with a large population-based sample aged 3.5–12 years. Further studies should assess its screening potential by investigating its convergent validity with diagnostic information.

Head start parents' vocational preparedness indirectly predicts preschoolers' physical and relational aggression

Severe poverty has profound impacts on child outcomes, yet much of the research on poverty fails to consider the psychological experiences of poverty, frames low-socioeconomic status families as a monolith, and until recently, has not considered the utility of behavior within the poverty context. This short-term (4 months) longitudinal study was designed to consider children's aggression as predicted by their inhibitory control (IC) and parents' experiences of poverty-related strain in an urban Head Start sample. At Time 1, parents reported on their family's economic situation (income, family size), education, vocational preparedness, and completed a measure of psychological economic strain; children (N = 90; Mage = 52.78 months) completed two IC tasks (Day/Night Stroop; Whisper). Four months later, parents completed the Preschool Proactive and Reactive Aggression survey, used to assess children's physical and relational aggression. Mediation analyses supported that physical and relational aggression were both fully mediated from parents' vocational preparedness, though through different mechanisms. Physical aggression was mediated by parents' psychological economic strain. Relational aggression was mediated through children's IC. Findings support the proposal that aggression should be viewed within context and that typical assumptions about developmental patterns of physical aggression may not hold for all children.

The Genetic, Environmental, and Cultural Forces Influencing Youth Antisocial Behavior Are Tightly Intertwined

The aggressive and rule-breaking behaviors that constitute youth antisocial behavior (ASB) are shaped by intertwined genetic, developmental, familial, spatial, temporal, cultural, interpersonal, and contextual influences operating across multiple levels of analysis. Genetic influences on ASB, for example, manifest in different ways during different developmental periods, and do so in part as a function of exposure to harsh parenting, delinquent peers, and disadvantaged neighborhoods. There is also clear evidence documenting societal effects, time-period effects, sex-assigned-at-birth effects, and cohort effects, all of which point to prominent (and possibly interconnected) cultural influences on ASB. In short, ASB is shaped by individuals' current and prior environmental experiences, genetic risks, and the time and place in which they live. This review seeks to illuminate already documented instances of interplay among the multilevel etiologic forces impinging on youth ASB, with the goal of facilitating additional research.

The role of harsh parenting practices in early- to middle-childhood socioemotional development: An examination in the Millennium Cohort Study

Patterson's coercion model describes a gradual escalation in maladaptive parent-child transactions whereby externalizing behaviors lead to increases in maladaptive parenting and vice versa. The current study investigates the role of (predominantly mother-reported) harsh parenting practices in the within-person development of conduct problems, hyperactive/inattentive behaviors, and emotional problems. A random-intercept cross-lagged panel model was fit across ages 3, 5, and 7 (N = 14,037, 49% female, 84% White) using the UK population-representative Millennium Cohort Study. Findings support Patterson's coercion model, providing evidence for reciprocal within-family relations between parenting practices and child behaviors. They suggest the importance of addressing parenting difficulties in families where children present with socioemotional difficulties in order to help prevent the accumulation of additional issues.

Individual differences in the development of youth externalizing problems predict a broad range of adult psychosocial outcomes

This study examined how youth aggressive and delinquent externalizing problem behaviors across childhood and adolescence are connected to consequential psychosocial life outcomes in adulthood. Using data from a longitudinal, high-risk sample (N = 1069) that assessed children and their parents regularly from early childhood (ages 3-5) through adulthood, multilevel growth factors of externalizing behaviors were used to predict adult outcomes (age 24-31), providing a sense of how externalizing problems across development were related to these outcomes via maternal, paternal, teacher, and child report. Findings indicated strong support for the lasting connections between youth externalizing problems with later educational attainment and legal difficulties, spanning informants and enduring beyond other meaningful contributors (i.e., child sex, cognitive ability, parental income and education, parental mental health and relationship quality). Some support was also found, although less consistently, linking externalizing problems and later alcohol use as well as romantic relationship quality. Delinquent/rule-breaking behaviors were often stronger predictors of later outcomes than aggressive behaviors. Taken together, these results indicate the importance of the role youth externalizing behaviors have in adult psychosocial functioning one to two decades later.

Co-development of aggression in elementary school children: The predictive roles of victimization experiences

Aggression among peers is a common and serious problem in school-age children. Physical, relational, and cyber aggression often occur simultaneously but may exhibit heterogeneous developmental patterns. We aimed to identify heterogeneous co-developmental patterns of physical, relational, and cyber peer aggression and to investigate the contributions of victimization experiences to co-developmental trajectories. Participants were 2869 elementary school students (56.2% boys), initially in fourth grade (M_age  = 10.51 years) in China. Longitudinal data on peer aggression were collected from participants semiannually for 2 years. Data on victimization experiences were collected in the initial measurement wave. Parallel process latent curve growth modeling produced four co-developmental trajectories of peer aggression: High Desisting group, Moderate-Increasing group, Moderate-Physical and Relational Aggression group, and Low Stable group. Multivariate logistic regression analyses revealed that childhood emotional abuse, psychological maltreatment by teachers, as well as physical peer victimization, and cyber peer victimization, served as risk factors for severe co-developmental trajectories. The findings highlight the co-development of physical, relational, and cyber aggression. The identification of risk factors for co-developmental trajectories points to the need for continued monitoring and protection from ongoing victimization experiences in the family and school settings to prevent or ameliorate aggressive behavior.

Dominance in humans

Dominance captures behavioural patterns found in social hierarchies that arise from agonistic interactions in which some individuals coercively exploit their control over costs and benefits to extract deference from others, often through aggression, threats and/or intimidation. Accumulating evidence points to its importance in humans and its separation from prestige-an alternate avenue to high status in which status arises from information (e.g. knowledge, skill, etc.) or other non-rival goods. In this review, we provide an overview of the theoretical underpinnings of dominance as a concept within evolutionary biology, discuss the challenges of applying it to humans and consider alternative theoretical accounts which assert that dominance is relevant to understanding status in humans. We then review empirical evidence for its continued importance in human groups, including the effects of dominance-independently of prestige-on measurable outcomes such as social influence and reproductive fitness, evidence for specialized dominance psychology, and evidence for gender-specific effects. Finally, because human-specific factors such as norms and coalitions may place bounds on purely coercive status-attainment strategies, we end by considering key situations and contexts that increase the likelihood for dominance status to coexist alongside prestige status within the same individual, including how: (i) institutional power and authority tend to elicit dominance; (ii) dominance-enhancing traits can at times generate benefits for others (prestige); and (iii) certain dominance cues and ethology may lead to mis-attributions of prestige. This article is part of the theme issue 'The centennial of the pecking order: current state and future prospects for the study of dominance hierarchies'.

The Effect of Left-Behind Experience and Self-Esteem on Aggressive Behavior in Young Adults in China : A Cross-Sectional Study

There is little investigation on the independent effects of left-behind experience (LBE) on self-esteem and aggressive behavior in Chinese young adult populations, or the interaction effects of LBE and self-esteem on aggressive behavior. Thus, a school-based health survey was conducted in Anhui province in China in 2017. A total of 4,154 college students completed standard questionnaires which contain details of left-behind-related characters, self-esteem, aggressive behavior, and sociodemographic profile. Of included students, 55.3% were those with LBE (LBEs). Compared to students without left-behind experiences (NLBEs), LBEs had significantly increased scores of aggressive behavior and decreased score of self-esteem. The increased aggression in LBEs was highly related to longer left-behind duration, younger age of left-behind for the first time, and decreased self-esteem. On the other side, the aggressive behavior was demonstrated negatively correlated with self-esteem in both LBEs and NLBEs. There was an interaction effect of left-behind duration and self-esteem on physical aggression and of frequency of contacting with parents and self-esteem on verbal aggression. Besides, the interaction of primary caregiver and self-esteem on hostility and aggression toward self were also observed, respectively. Our results indicated LBEs and low self-esteem are associated with increased risk of aggressive behavior in Chinese young adults. The increased aggressive behavior in LBEs were highly related to longer left-behind duration, younger age of left-behind for the first time and decreased self-esteem. In those LBEs with some certain left-behind-related characters, aggressive behavior decreased more prominently with the increase of self-esteem. Strategies to improve self-esteem, particularly among young adults who have certain characters of LBE, should be a significant component of prevention and interventions of aggressive behavior.

Risk of Injury to Others: The Development of an Algorithm to Identify Children and Youth at High-Risk of Aggressive Behaviours

Youth violence is considered one of the most preventable causes of morbidity and premature mortality. Various risk factors have previously been identified, however, there is presently a crucial need to develop effective decision-support tools in order to identify children and youth at increased risk for violence. The current study utilised data collected from the interRAI Child and Youth Mental Health Screener (ChYMH-S), within the province of Ontario, to develop and validate a methodology for the purpose of identifying young persons who were at greater risk of harm to others. Additional data from 59 mental health agencies validated the algorithm, and it was found to be a strong predictor of harmful behaviour toward others. The RIO algorithm provides a valuable decision-support tool with strong psychometric properties that may be used to identify young persons who exhibit signs or symptoms associated with increased likelihood of harm toward others, in order to provide early intervention efforts for these vulnerable youth, thereby reducing the likelihood of future aggressive behaviours.

Female Forensic Patients May Be an Atypical Sub-type of Females Presenting Aggressive and Antisocial Behavior

The percentage of forensic psychiatric patients who are female varies from 5 to 13% in Europe, rises to 18% in England and Wales, and sits at 15% in Canada. Similarly, many fewer women than men are incarcerated in correctional facilities. While these statistics supposedly reflect less antisocial and aggressive behavior (AAB) among females than males, not all findings support this supposition. Data from prospective longitudinal studies show that aggressive and antisocial behavior onsets in childhood, and in a small group of females it remains stable across the life-span. Unlike similar males, few of these females are convicted of crimes. This article begins with a review of descriptive studies of females sentenced by criminal courts to treatment in forensic psychiatric hospitals and moves on to present evidence showing that most female AAB does not lead to criminal prosecution. Next, studies of female AAB are reviewed, noting that it onsets in early childhood and, that in a small group remains stable across the life-span. Subsequent sections of the article focus on the two most common mental disorders presented by female forensic patients, schizophrenia and borderline personality disorder, highlighting what is known about the sub-groups of women with these disorders who present AAB. The article concludes with recommendations for earlier identification by psychiatric services of women presenting mental disorders and AAB, treatments to reduce both the symptoms of their mental disorders and their life-long AAB, and the research that is needed in order to improve the effectiveness of these treatments. The real possibilities of prevention of the development of AAB, and even perhaps aspects of the mental disorders that plague female forensic patients, are described.

The effect of classroom aggression-related peer group norms on students' short-term trajectories of aggression

Using a four-wave/seven-month longitudinal design with a sample of 1595 preadolescents (53% boys, 47% girls, M_age  = 10.2 years) from 63 fourth-, fifth- and sixth- grade classrooms in nine mixed-sex schools in Bogotá, Colombia, we examined whether growth trajectories of measures of overt and relational aggression varied as a function of classroom norms for aggression. Multilevel growth mixture modeling revealed (a) distinct trajectories of overt and relational aggression for boys and girls and (b) that norm salience (i.e., the process by which a group norm is made salient via the punishments or reinforcements to the behavior within the group) was a better predictor of associations with trajectories of overt and relational aggression than were perceived injunctive norms (i.e., the perceived standards of what is approved or disapproved in a social context). In classrooms where popular or accepted children were perceived by their peers as aggressive, more boys followed an increasing trajectory of overt and relational aggression than a low-stable trajectory, and more girls followed a high-stable trajectory of relational aggression than a low-stable trajectory. These findings are discussed in terms of the practical implications for the design of educational interventions aimed at preventing aggression in classroom settings.

Externalizing Risk Pathways for Adolescent Substance Use and Its Developmental Onset: A Canadian Birth Cohort Study: Trajectoires de comportements extériorisés et le risque pour l'initiation et l'usage de substances des adolescents : Une étude de cohorte de naissance canadienne

OBJECTIVE

Only a minority of drug and alcohol users develops a substance use disorder. Previous studies suggest that this differential vulnerability commonly reflects a developmental trajectory characterized by diverse externalizing behaviors. In this study, we examined the relation between child and adolescent externalizing behaviors and adolescent substance use in a prospectively followed Canadian birth cohort, accounting for the temporal sequence of a wide variety of contributing factors.

METHODS

Two hundred and forty-two adolescents followed since birth (date range: 1996 to 2012) were assessed on externalizing behavior (age 17 months to 16 years), alcohol and cannabis use at age 16, age of alcohol use onset, family history of substance use problems, family functioning (age 11 to 15), sensation seeking (age 16), prenatal substance exposure, socioeconomic status (age 1 to 9), and sex.

RESULTS

Age of alcohol use onset was predicted by a family history of substance use problems, externalizing traits from ages 6 to 10 and 11 to 16, sensation seeking at age 16, prenatal alcohol and tobacco exposure and family functioning at ages 11 to 15. High frequencies of alcohol and cannabis use at age 16 were both predicted by externalizing traits from ages 11 to 16, a family history of substance use problems and sensation seeking after controlling for other individual, environmental and familial variables. The association between familial substance use problems and substance use during adolescence was partially mediated by externalizing traits from age 11 to 16.

CONCLUSIONS

The present findings provide prospective evidence for a developmental risk pathway for adolescent substance use, potentially identifying those who could benefit from early interventions.

The Development of Respect in Children and Adolescents

Respect is an integral part of everyday life. It is a virtue central to the aim of living an ethically good life. Despite its importance, little is known about its emergence, development, correlates, and consequences. In this monograph, we aim to fill this gap by presenting empirical work on children's and adolescents' thinking and feelings about respect. Specifically, we examined the development of respect in ethnically diverse samples of children between the ages of 5 and 15 years (N = 476). Using a narrative and semi-structured interview, as well as self-, caregiver- and teacher-reports, and peer-nominations, we collected information on children's respect conceptions and reasoning, as well as on the social-emotional correlates and prosocial and aggressive behavioral outcomes of respect. We begin with a review of theoretical accounts on respect. This includes a selective overview of the history of respect in philosophy and psychology in Chapter I. Here, we discuss early writings and conceptualizations of respect across the seminal works of Kant and others. We then provide an account of the various ways in which respect is conceptualized across the psychological literature. In Chapter II, we review extant developmental theory and research on respect and its development, correlates, and behavioral consequences. In this chapter, as part of our developmental framework, we discuss how respect is related and distinct from other emotions such as sympathy and admiration. Next, we describe our methodology (Chapter III). This includes a summary of our research aims, samples, and measures used for exploring this novel area of research. Our primary goals were to examine how children and adolescents conceptualize respect, how their conceptualizations differ by age, whether and to what degree children feel respect toward others' "good" behavior (i.e., respect evaluations for behavior rooted in ethical norms of kindness, fairness, and personal achievement goals), and how children's respect is related to other ethical emotions and behaviors. The next three chapters provide a summary of our empirical findings. Chapter IV showcases our prominent results on the development of children's conceptions of respect. Results revealed that children, across age, considered prosociality to be the most important component involved in conceptualizations of respect. We also found age-related increases in children's beliefs about fairness as a core component of respect. Children and adolescents also reported feeling higher levels of respect for behavior in the ethical domain (e.g., sharing fairly and inclusion) than behavior in the personal domain (i.e., achieving high grades in school). Chapter V investigates how sympathy and feelings of sadness over wrongdoing relate to respect conceptions and respect for behavior. Our findings show that sadness over wrongdoing was positively associated with adolescents' fairness conceptions of respect. Sympathy was positively related to children's feelings of respect toward others' ethical behavior. In Chapter VI, we present links between respect and social behavior. Our findings provide some evidence that children's feelings of respect are positively linked with prosocial behavior and children's conceptions of respect (particularly those reflecting themes of fairness and equality) are negatively related to physical aggression. In the last two chapters, we discuss the empirical findings and their implications for practice and policy. In Chapter VII, we draw upon recent work in the field of social-emotional development to interpret our results and provide insight into how our findings extend previous seminal work on the development of respect from early childhood to adolescence. Finally, in Chapter VIII, we conclude by discussing implications for educational and clinical practice with children and adolescents, as well as social policies aimed at reducing discrimination and nurturing children's well-being and positive peer relationships.

Listening In: How Parent-Child Communication Relates to Social and Physical Aggression

In this study, we investigated the relations between features of parent-child conversations (neutral talk, positive and negative in-dyad and out-dyad talk) and children's social and physical aggression from ages 9-18. Participants were 297 youth (52% girls) of about 9 years old at Time 1 and their parent. Fifty-two percent of this United States sample identified as White, 20% Black, 20% Hispanic, 8% other races/ethnicities. One hundred eighty-seven parents participated in the parent-child observation task. Ninety four percent of parent participants were mothers. Parent-child conversations were observed in the laboratory during preadolescence, and teachers reported child's aggression. Using multinomial logit analyses, we found that coded observations of communication features predicted membership in linear trajectories of social and physical aggression across nine years of adolescence; trajectories were derived via mixture modeling. Parent and child communication characteristics were related to trajectories of aggression that spanned preadolescence and adolescence; however, not all predicted associations were significant. Children's talk about neutral topics predicted being on a lower social aggression trajectory. Positive out-dyad talk from children was related to being on a lower physical aggression trajectory, as was parent in-dyad positive talk. After controlling for other factors, neither parent nor child in- or out-dyad negative talk was associated with social or physical aggression. These findings highlight the importance of positive communication by youth and toward youth in association with long-term social adjustment.

Victims Become Covert Aggressors: Gender Differences in the Mediating Effects of Rumination on Anger and Sadness

This longitudinal study examined the link between peer victimization and relational aggression by testing the mediating roles of sadness and anger rumination, with attention to gender differences, among Chinese adolescents. Survey measures were administrated to 2,152 junior middle school students at two time points, one year apart. The results found that self-reported peer victimization (but not peer-nominated victimization) positively predicted relational aggression one year later, and this link was completely mediated by sadness and anger rumination. Specifically, perceived peer victimization exerted a positive influence on both sadness and anger rumination, thereby increasing adolescents' tendency to exhibit relational aggression one year later. Furthermore, victimized boys' elevated relational aggression was predominantly accounted for by their high sadness rumination, whereas victimized girls' elevated relational aggression was mainly due to their great anger rumination. Such a gender-difference suggests that interventions to reduce adolescents' externalizing problems may be most effective when tailored to each gender specifically.

The personality dispositions and resting-state neural correlates associated with aggressive children

Despite aggression being detrimental to children's physical health, mental health and social development, the dispositional and neurological antecedents of aggression in the child are poorly understood. Here we examined the relationship between trait aggression as measured by Buss and Warren's Aggression Questionnaire and personality traits measured with Big Five Questionnaire for Children in 77 primary-school children and recorded resting-state brain activity (fractional amplitude of low-frequency fluctuations [fALFF]) and resting-state functional connectivity (rsFC) using functional magnetic resonance imaging. The present results showed that trait aggression was negatively correlated with agreeableness and positively correlated with neuroticism. The brain analyses showed that children with a higher propensity for aggression had a lower fALFF mainly in the left superior temporal gyrus, right parahippocampal gyrus and left supramarginal gyrus. Physical and total aggressions were negatively associated with rsFC between the right parahippocampal gyrus and the right putamen. Further analysis revealed that this rsFC could moderate the influence of neuroticism on total aggression. Moreover, the results suggest the presence of a sex difference in the neurodevelopmental mechanisms underlying aggression in middle childhood. Overall, our findings indicate that aggressive children have lower agreeableness and higher neuroticism, and the underlying neural systems are mainly implicated in social judgment and empathy.

The growth of gossip: Socialization of relational aggression from adolescence to emerging adulthood

The extant literature suggests that relational aggression appears in early childhood, and gradually increases throughout adolescence. However, very little research has examined the growth of relational aggression from adolescence to emerging adulthood. In addition, research generally examines socializing factors of relational aggression, such as parenting, peers, siblings, or media in isolation. Accordingly, the aim of the current study was to examine these socializing factors conjunctively as predictors of the growth of relational aggression over time. Participants consisted of 500 adolescents who completed several questionnaires over a 7-year period (between ages 14-20 on average). Results revealed that the vast majority of individuals (88%) showed low levels of relational aggression that decreased over time. Conversely, a small proportion of individuals (12%) had high, increasing levels of relational aggression between adolescence and emerging adulthood. High levels of maternal psychological control, sibling hostility, and relational aggression in the media at the initial time point all predicted being in the high and increasing group.

Parallel Trajectories of Proactive and Reactive Aggression in Middle Childhood and Their Outcomes in Early Adolescence

This study used an accelerated longitudinal design to investigate trajectories of proactive and reactive aggression in middle childhood and their outcomes in early adolescence. Children (N = 1420; ages 5-12; 48% female) were assessed biannually over 6 school years. Classroom teachers rated students' proactive and reactive aggression throughout grades K-5; and multi-method (teacher-report, self-report, school records) measures of peer problems, depressive symptoms, academic performance, disciplinary actions, and school absenteeism were collected throughout grades 3-5. Latent class growth models were estimated to differentiate parallel-process trajectories of proactive-reactive aggression. Class membership was then examined as a predictor of outcomes at the end of 5th grade. The best-fitting solution had four trajectory classes: (1) low aggression, 76.7%; (2) high proactive-reactive aggression, 4.7%; (3) declining aggression, 4.9%; and (4) predominantly reactive aggression, 13.7%. Most classes showed seasonal upticks in aggressive behavior in the spring semester relative to fall; these were especially pronounced for proactive aggression, both as a variable and for the proactive-reactive class. Relative to their low-aggression peers, children in any elevated-aggression class had higher levels of peer problems, depressive symptoms, and disciplinary actions and lower GPAs at the end of 5th grade. The reactive class-which on no occasion had the highest total aggression-exhibited the most consistently unfavorable pattern of outcomes across methods and measures. Findings offer new insights concerning the multifinality and heterogeneity of aggressive behavior in childhood. Research, theory, and practice could benefit from adopting person-centered conceptualizations that consider the long-term trajectories, short-term variations, and proactive vs. reactive functions of youth aggression.

The Use of Indirect Aggression among Boys and Girls with and without Conduct Problems: Trajectories from Childhood to Adolescence

Though conceptually distinct from other behavior problems, indirect aggression (IA) is correlated with physical aggression and is linked to oppositional defiant disorder and conduct disorder from childhood to adolescence. Thus, IA could be part of the clinical picture of children with identified conduct problems (CP). However, trajectories of IA have not been studied in children with CP. In the present study, we evaluated and compared the mean trajectory of IA from 7 to 14 years of age in children with (n = 328; 47.6% girls) and without (n = 320; 51.3% girls) early clinically significant CP using both parent and teacher ratings. We then examined if sub-groups of children distinguished themselves by their use of IA over time and tested for sex differences. Latent growth models showed that children with CP used IA at higher rates over time than children without CP. Regardless of this higher frequency, the use of IA in both groups of children was best described by down-turned curvilinear trajectories peaking at 10 years of age. Growth mixture models showed that children without CP, according to parent and teacher ratings, and children with CP, according to parent ratings, both followed two trajectories of IA over time, with, respectively, 10% to 14% of them following a high trajectory. As for sex differences, the use of IA of boys and girls without CP did not differ, but differences emerged for children with CP, with girls using IA more frequently. The clinical implications of the findings are discussed.

Relations between forms and functions of aggression and moral judgments of aggressive transgressions

The present study sought to examine the influence of aggressive behavior, psychopathy, and gender on moral judgments of aggressive transgressions. A two-dimensional conceptualization of aggression was used, such that proactive relational aggression, reactive relational aggression, proactive physical aggression, and reactive physical aggression were treated as distinct subtypes of aggression and also as distinct subtypes of moral judgments of aggression. Participants were 421 emerging adults (215 women). Self-report measures of aggression, psychopathy, and moral judgments were collected. Peer-reports of aggression and psychopathy were obtained from a randomly assigned subsample of 73 participants (46 women) for validity purposes. Unique associations were found between subtypes of aggression and corresponding moral judgments of the same subtypes.

Preweaning Paternal Deprivation Impacts Parental Responses to Pups and Alters the Serum Oxytocin and Corticosterone Levels and Oxytocin Receptor, Vasopressin 1A Receptor, Oestrogen Receptor, Dopamine Type I Receptor, Dopamine Type II Receptor Levels in Relevant Brain Regions in Adult Mandarin Voles

Although maternal separation and neonatal paternal deprivation (PD) have been found to exert a profound and persistent effects on the physiological and behavioural development of offspring, whether preweaning PD (PPD; from PND 10 to 21) affects maternal and parental responses to pups and the underlying neuroendocrine mechanism are under-investigated. Using monogamous mandarin voles (Microtus mandarinus), the present study found that PPD increased the latency to approach a pup-containing ball, decreased the total durations of sniffing and contacting a pup-containing ball and walking and increased the total duration of inactivity in both sexes. Moreover, PPD decreased serum oxytocin levels and increased corticosterone levels, but only in females. Furthermore, in both males and females, PPD decreased the expression of oxytocin receptor mRNA and protein in the medial preoptic area (MPOA), nucleus accumbens (NAcc) and medial prefrontal cortex (mPFC), but increased it in the medial amygdala (MeA) and decreased the expression of oestrogen receptor mRNA and protein in the MPOA. PPD increased the expression of dopamine type I receptor in the NAcc, but decreased it in the mPFC. PPD decreased dopamine type II receptor (D2R) in the NAcc both in males and females, but increased D2R in the mPFC in females and decreased D2R protein expression in males. Moreover, PPD decreased vasopressin 1A receptor (V1AR) in the MPOA, MeA and mPFC, but only in males. Our results suggest that the reduction of parental responses to pups induced by PPD may be associated with the sex-specific alteration of several neuroendocrine parameters in relevant brain regions.

Taming anger and trusting others: Roles of skin conductance, anger regulation, and trust in children's aggression

Proactive and reactive aggression subtypes are distinguishable as early as the preschool years. However, their early physiological and social-emotional correlates have not been examined simultaneously. We tested whether children's skin conductance level, anger regulation, and trust in others were differentially related to their proactive and reactive aggression. Four-year-olds and their primary caregivers were recruited from a large Canadian city (N = 150). Controlling for reactive aggression, higher trust was associated with lower proactive aggression, but only for children with low anger regulation or skin conductance level. Controlling for proactive aggression, lower anger regulation was related to higher reactive aggression, and higher trust was related to higher reactive aggression for children with high skin conductance level. Findings highlight the unique and collective relations of physiology, emotion regulation, and trust to different forms of aggression in early childhood. Statement of contribution What is already known on this subject Proactive and reactive aggression subtypes are distinguishable as early as the preschool years. Unique physiological and social-emotional correlates of each subtype have been studied in middle and late childhood. Trust is a critical milestone for positive social interactions in early childhood and has been linked to aggression. What the present study adds Physiological and social-emotional correlates are uniquely linked to subtypes of aggression already at age 4. Trust is differentially linked to aggression subtypes as a function of anger regulation and skin conductance level.

Development of Aggression Subtypes from Childhood to Adolescence: a Group-Based Multi-Trajectory Modelling Perspective

The persistence of elevated subtypes of aggression beginning in childhood have been associated with long-term maladaptive outcomes. Yet it remains unclear to what extent there are clusters of individuals following similar developmental trajectories across forms (i.e., physical and indirect) and functions (i.e., proactive and reactive) of aggression. We aimed to identify groups of children with distinct profiles of the joint development of forms and functions of aggression and to identify risk factors for group membership. A sample of 787 children was followed from birth to adolescence. Parent and teacher reports, and standardised assessments were used to measure two forms and two functions of aggressive behaviour, between six and 13 years of age along with preceding child, maternal, and family-level risk-factors. Analyses were conducted using a group-based multi-trajectory modelling approach. Five trajectory groups emerged: non-aggressors, low-stable, moderate-engagers, high-desisting, and high-chronic. Coercive parenting increased membership risk in the moderate-engagers and high-chronic groups. Lower maternal IQ increased membership risk in both high-desisting and high-chronic groups, whereas maternal depression increased membership risk in the high-desisting group only. Never being breastfed increased membership risk in the moderate-engagers group. Boys were at greater risk for belonging to groups displaying elevated aggression. Individuals with chronic aggression problems use all subtypes of aggression. Risk factors suggest that prevention programs should start early in life and target mothers with lower IQ. Strategies to deal with maternal depression and enhance positive parenting while replacing coercive parenting tactics should be highlighted in programming efforts.

Normative Trends in Physically Aggressive Behavior: Age-Aggression Curves from 6 to 24 Months

OBJECTIVE

To investigate age-related trends in physically aggressive behaviors in children before age 2 years.

STUDY DESIGN

A normative US sample of 477 mothers of 6- to 24-month-old children reported on the frequency of 9 interpersonally directed aggressive child behaviors, and hurting animals, in the past month.

RESULTS

Almost all (94%) of the children were reported to have engaged in physically aggressive behavior in the past month. Based on 2-part regression models, the prevalences of kicking (OR, 1.70; P = .023), pushing (OR, 3.22; P < .001), and swiping (OR, 1.78; P = .018) increased with years of age, but the prevalence of hair pulling decreased with age (OR, 0.55; P = .020). The prevalences of hitting and throwing increased initially, then plateaued at age 18-20 months, and then decreased (quadratic aOR, 0.13 and 0.16; P < .001 and .010, respectively). The frequencies of hitting (R² = .05; P < .001) and throwing (R² = .03; P = .030) increased, and the frequencies of hair pulling (R² = .07; P < .001) and scratching (R² = .02; P = .042) decreased with age (P values adjusted for false discovery rate).

CONCLUSIONS

Physically aggressive behavior in the 6- to 24-month age range appears to be nearly ubiquitous. Most, but not all, forms of physical aggression increase with age. These results can guide pediatricians as they educate and counsel parents about their child's behavior in the first 2 years of life.

Relations between Parent Psychological Control and Parent and Adolescent Social Aggression

Parent-child interactions and parenting behavior may be related to social aggression among adolescents, and adolescents' social aggression may relate to parents' social aggression. This study investigated (a) whether parent psychological control predicted future adolescent and parent social aggression in their own peer relationships, (b) whether parents' social aggression was related to their use of psychological control within the parent-adolescent relationship (c) whether adolescents' and parents' social aggression was associated with changes in each other's social aggression over time, and (d) change in psychological control. Participants were 174 racially/ethnically diverse parent-adolescent dyads assessed longitudinally for four years. Adolescents were approximately 15-years-old at the first time point. The adolescent sample was 52% girls and 56% identified as White, 22% as Black or African American, 16% as Hispanic, and 5% as mixed race/ ethnicity. Ten percent of the parent participants were fathers. Parents self-reported their psychological control and social aggression, and their adolescents' teachers reported adolescents' social aggression. Hypotheses were tested using longitudinal structural equation modeling and a latent growth curve analysis. The hypothesized effect of parent's psychological control on parent's future aggression with their own peers was supported. Psychological control positively predicted parent aggression from T2 to T3 (β = .28, p < .05) and from T3 to T4 (β = .37, p < .05). Other hypotheses were not supported. The findings suggest that the parent-child relationship may influence the parent's functioning in their own peer relationships. Parents' peer relations seem to have important implications for their own wellbeing and the parent-child relationship.

Risk Factors Associated With Boys' and Girls' Developmental Trajectories of Physical Aggression From Early Childhood Through Early Adolescence

Importance

This study used multitrajectory modeling to identify distinct trajectories of physical aggression from ages 1.5 to 13 years for boys and girls.

Objectives

To trace the development of boys' and girls' physical aggression problems from infancy to adolescence using mother ratings, teacher ratings, and self-ratings and to identify early family predictors of children on the high physical aggression trajectories.

Design, Setting, and Participants

This cohort study used data from the Quebec Longitudinal Study of Child Development (QLSCD), a study of a representative, population-based sample of 2223 infants born in 1997 and 1998 in the Canadian province of Quebec. The dates of analysis were January 2017 to January 2018.

Main Outcomes and Measures

Trained research assistants conducted 7 interviews (at child ages 1.5, 2.5, 3.5, 4.5, 5, 6, and 8 years) with the person most knowledgeable about the child (mothers in 99.6% [2214 of 2223] of cases). Teachers assessed the child's behavior at ages 6, 7, 8, 10, 12, and 13 years. Self-reports of behavior problems were obtained from the child at ages 10, 12, and 13 years.

Results

The sample included 2223 participants, 51.2% of whom were boys and 91.2% of whom were of white race/ethnicity. The mean response rate for mother ratings of physical aggression during the first 8 years of life was 80.9% (range, 65.1%-91.7%). For teacher ratings of physical aggression from ages 6 to 13 years, the mean response rate was 45.7% (range, 35.4%-56.9%), while the mean response rate of physical aggression assessment from self-ratings between ages 10 and 13 years was 57.9% (range, 55.2%-60.5%). Attrition was higher among families with low socioeconomic status and single-parent families, as well as among young mothers and mothers who were not fluent in French or English. A statistical analysis to examine the consequences of attrition was included. For boys and girls, the frequency of physical aggressions increased from age 1.5 years (2039 [91.7%]) to age 3.5 years (1941 [87.3%]) and then substantially decreased until age 13 years (1228 [55.2%]). Three distinct developmental trajectories of physical aggression were observed for girls and 5 for boys. Most family characteristics measured at 5 months after the child's birth were associated with a high physical aggression trajectory for boys and girls.

Conclusions and Relevance

Family characteristics at 5 months after the child's birth could be used to target preschool interventions aimed at preventing the development of boys' and girls' chronic physical aggression problems.

Past-year relational victimization is associated with a blunted neural response to rewards in emerging adults

Anhedonia is associated with multiple forms of psychopathology, yet relatively, little is known about how anhedonia develops. Emerging evidence suggests that anhedonia is the result of interactions between life stress and the brain's reward systems, and that social stress, in particular, may drive these processes. One potent form of social stress is peer victimization, but very little research has focused on peer victimization beyond adolescence, and even less has examined the associations between peer victimization and neural response to rewards. The present study sought to identify associations between past-year history of peer victimization and neural response to rewards in emerging adults (N = 61). Relational and physical forms of victimization were assessed separately since these distinct types of social stress have different trajectories across development and different associations with psychopathology. Reward sensitivity was indexed with the event-related potential component known as the reward positivity, which was elicited using a forced-choice monetary reward guessing task. Results demonstrated that past-year relational, but not physical, victimization was associated with a blunted neural response to rewards. These findings provide insight into one potential mechanism in the etiology of anhedonia, which may, in turn, help us to better identify pathways to multiple psychopathologies.

Universal Coping Power for pre-schoolers: Effects on children's behavioral difficulties and pre-academic skills

The Coping Power Program has been adapted as a universal prevention model (Coping Power Universal) aimed to reduce children's behavioral difficulties in Italian primary and nursery classes. The current study aimed to determine whether the version of the Universal Coping Power for pre-schoolers could reduce behavioral problems in school and home contexts, and could produce transfer effects on children's pre-academic skills. The sample included 102 five-year-old children who attended six pre-school classes located in Rovigo (Italy). Classes were randomly assigned to the intervention or to the control condition. Both parents and teachers indicated a significant reduction in behavioral problems for Coping Power classes, and teachers rated improvement in children's pre-mathematics, and language abilities. The results of this study are promising, suggesting pre-schoolers' social-emotional and pre-academic skills may benefit from the Universal Coping Power program.

Self-Reported Moral Emotions and Physical and Relational Aggression in Early Childhood: A Social Domain Approach

This study examined discrepancies between 4- and 7-year-olds' (n = 135; M_age  = 5.65) self-reported affect following hypothetical moral versus social-conventional transgressions and their associations with teacher-rated physical and relational aggression concurrently and 9-months later. Negative emotion ratings in response to prototypical moral transgressions were not associated with children's aggression. When transgressions were described as no longer prohibited by rules and authority figures, children reporting more negative affect in response to moral as compared to conventional violations were less physically aggressive at Wave 1 and showed relative and mean-level declines in physical aggression over time. Relational aggression was not associated with self-reported emotions. Findings indicate the importance of distinguishing between types of transgressions and forms of aggression in studying moral emotions.

The aggressive child

Aggression in children is a common transdiagnostic symptom associated with a wide range of developmental and mental health problems. It emerges early and without intervention, may increase in severity as the child grows stronger. Aggressive children are more likely to experience physical and mental illness, unemployment, poverty and forensic problems as adults. Strategies to prevent aggression must address risk factors: low maternal education, adolescent pregnancy, in utero exposure to tobacco and alcohol, poverty, coercive parenting, childhood maltreatment and bullying victimisation. The aggressive child requires a comprehensive assessment to identify and manage underlying or comorbid problems, to understand the reasons for the aggressive behaviour and to detect modifiable factors that exacerbate or perpetuate the aggression. Psychosocial interventions include parenting skills training and child-directed cognitive behavioural therapy, whereas pharmacotherapy may be used to treat underlying developmental or mental health problems or to manage the aggression.

Predictors of childhood trajectories of overt and indirect aggression: An interdisciplinary approach

The aim of this study was to advance our understanding of the development of aggression in boys and girls by testing a model combining insights from both evolutionary theory and developmental psychology. A sample of 744 children (348 girls) between six and 13 years old was recruited in schools with high deprivation indices. Half of the sample (N = 372; 40.1% girls) had received special educational services for behavioral and/or socio-emotional problems. Two trajectories for overt aggression and two trajectories for indirect aggression were identified and binomial logistic regressions were used to identify environmental predictors and sex-specific patterns of these trajectories. Results indicated that peer rejection predicted overt aggression and indirect aggression and that extraversion and male sex predicted overt aggression. The results also showed that interaction between parental practices and some child temperament traits predicted overt aggression (coercion and lack of supervision associated with extraversion or low effortful control) or indirect aggression (coercion and neglect associated with negative affect or low effortful control), and the absence of a father figure predicted high indirect aggression in girls.

Reactive and proactive aggression as meaningful distinctions at the variable and person level in primary school-aged children

Reactive and proactive aggression is a dichotomous classification of aggression in adults and children. This distinction has been supported by a number of variable-based and factor analytic studies. Due to high inter-correlations, however, the reactive-proactive aggression distinction may not be entirely useful for understanding how group or individual aggressive behavior varies in children and adolescents. Drawing on a sample of primary school-aged children (N = 242) aged 7-12 years, this study sought to determine whether reactive and proactive aggression could be distinguished at the variable-level and the person-level in children. Exploratory Factor Analysis of data from an aggression instrument measuring both functions and forms of aggression, found a two-factor construct of aggression constituted by a reactive and proactive aggression factor. A person-based analysis was then conducted after classifying children according to the presence of reactive and/or proactive aggression. Discriminant function analysis was used to discern whether classifications on the basis of aggression function produced meaningful distinctions in terms of antisocial traits and emotional valence and intensity measures. Two functions were identified which distinguished children with different combinations of reactive and proactive aggression. Reactive-only aggressive children were defined primarily by high levels of impulsivity, while proactive-only children were defined primarily by higher levels of antisocial traits. Children high in both types of aggression exhibited both the presence of antisocial traits and impulsivity. Contrary to recent findings, this suggests that differences in aggression functions remain meaningful at the person level in children. Implications for interventions are discussed.

Longitudinal Associations between Depression and Aggression in Children and Adolescents

Due to the longstanding and detrimental effects of engaging in aggressive behaviour and of experiencing symptoms of internalizing problems in children and adolescents, there is an increasing interest in identifying the temporal sequence between these 2 problems with previous research yielding inconsistent findings. Therefore, the longitudinal links between relational aggression, physical aggression, and depression were examined across 7 years in a sample of 643 children (54 % girls) aged 10 at Time 1. Three models were compared- (1) the failure model, in which aggression predicted depression, (2) the acting out model, in which depression predicted aggression, and (3) a reciprocal model, in which both aggression and depression shared a reciprocal relation over time. Cross-lagged path analyses using structural equation modeling supported the failure model (i.e., engaging in relational and physical aggression predicts subsequent depressive symptoms). Findings were similar for boys and girls. These findings add to the literature suggesting that externalizing problems precede internalizing problems.

Longitudinal Links between Executive Function, Anger, and Aggression in Middle Childhood

Previous research has indicated that executive function (EF) is negatively associated with aggressive behavior in childhood. However, there is a lack of longitudinal studies that have examined the effect of deficits in EF on aggression over time and taken into account different forms and functions of aggression at the same time. Furthermore, only few studies have analyzed the role of underlying variables that may explain the association between EF and aggression. The present study examined the prospective paths between EF and different forms (physical and relational) and functions (reactive and proactive) of aggression. The habitual experience of anger was examined as a potential underlying mechanism of the link between EF and aggression, because the tendency to get angry easily has been found to be both a consequence of deficits in EF and a predictor of aggression. The study included 1,652 children (between 6 and 11 years old at the first time point), who were followed over three time points (T1, T2, and T3) covering 3 years. At T1, a latent factor of EF comprised measures of planning, rated via teacher reports, as well as inhibition, set shifting, and working-memory updating, assessed experimentally. Habitual anger experience was assessed via parent reports at T1 and T2. The forms and functions of aggression were measured via teacher reports at all three time points. Structural equation modeling revealed that EF at T1 predicted physical, relational, and reactive aggression at T3, but was unrelated to proactive aggression at T3. Furthermore, EF at T1 was indirectly linked to physical aggression at T3, mediated through habitual anger experience at T2. The results indicate that deficits in EF influence the later occurrence of aggression in middle childhood, and the tendency to get angry easily mediates this relation.

Characteristics of Physical Aggression in Children of Immigrant Mothers and Non-immigrant Mothers: A Cross-Sectional Analysis of the Survey of Young Canadians

Physical aggression (PA) is important to regulate as early as the preschool years in order to ensure healthy development of children. This study aims to determine the prevalence and characteristics of PA in children of immigrant and non-immigrant mothers. Secondary data analysis was conducted using the nationwide 2010 Survey for Young Canadians, limited to children 4-9 years of age. Bivariate and multivariable logistic regression was performed, with the outcome, PA, and covariates including maternal, child, household and neighbourhood characteristics. Twenty percent of children of non-immigrant mothers and 16% of children of immigrant mothers reported PA. The only common characteristic of PA between children of non-immigrant (Adj OR 1.44, 95% CI 1.09-1.89) and immigrant mothers (Adj OR 2.08, 95% CI 1.07-4.03) was viewing violent movies/shows. The characteristics of PA differ between children of immigrant versus non-immigrant mothers therefore healthcare providers, policy makers, and researchers should be mindful to address PA in these two groups separately, and find ways to tailor current recommended coping strategies and teach children alternative ways to solve problems based on their needs.

Depression in early adolescence: Contributions from relational aggression and variation in the oxytocin receptor gene

Interpersonal stress arising from relational aggression (RA)-the intentional effort to harm others via rejection and exclusion-may increase risk for depression in youth. Biological vulnerabilities related to the hormone oxytocin, which affects social behavior and stress responses, may exacerbate this risk. In a community sample of 307 youth (52% female; age range = 10-14 years), we tested whether (1) the association between RA and subsequent depressive symptoms was mediated through social problems and (2) a single nucleotide polymorphism (rs53576) in the oxytocin receptor gene (OXTR) moderated this indirect association between RA and depression, where GG homozygotes are predicted to be more sensitive to the effects of social problems than A-allele carriers. Youth-reported RA and depressive symptoms were measured using a structured interview and a questionnaire, respectively. DNA was extracted from saliva collected with Oragene kits. Consistent with the interpersonal theory of depression, the association between relational aggression and subsequent depressive symptoms was mediated by social problems. This indirect effect was further moderated by rs53576 genotype, such that GG homozygotes showed a stronger mediation effect than A-carriers. These results suggest that rs53576 variants confer vulnerability for depression within the context of interpersonal risk factors, such that youth with the GG genotype may be particularly sensitive to the social consequences resulting from RA.

Psychometric properties of the Mental Health and Social Inadaptation Assessment for Adolescents (MIA) in a population-based sample

We report on the psychometric properties of the Mental Health and Social Inadaptation Assessment for Adolescents (MIA), a self-report instrument for quantifying the frequency of mental health and psychosocial adaptation problems using a dimensional approach and based on the DSM-5. The instrument includes 113 questions, takes 20-25 minutes to answer, and covers the past 12 months. A population-based cohort of adolescents (n = 1443, age = 15 years; 48% males) rated the frequency at which they experienced symptoms of Attention Deficit Hyperactivity Disorder (ADHD), Conduct Disorder, Oppositional Defiant Disorder, Depression, Generalized Anxiety, Social Phobia, Eating Disorders (i.e. DSM disorders), Self-harm, Delinquency, Psychopathy as well as social adaptation problems (e.g. aggression). They also rated interference with functioning in four contexts (family, friends, school, daily life). Reliability analyses indicated good to excellent internal consistency for most scales (alpha = 0.70-0.97) except Psychopathy (alpha = 0.46). The hypothesized structure of the instrument showed acceptable fit according to confirmatory factor analysis (CFA) [Chi-square (4155) = 9776.2, p = 0.000; Chi-square/DF = 2.35; root mean square error of approximation (RMSEA) = 0.031; Comparative Fit Index (CFI) = 0.864], and good convergent and discriminant validity according to multitrait-multimethods analysis. This initial study showed adequate internal validity and reliability of the MIA. Our findings open the way for further studies investigating other validity aspects, which are necessary before recommending the wide use of the MIA in research and clinical settings.

Coping power for preschool-aged children: a pilot randomized control trial study

AIM

Preschoolers with behavioural difficulties, both at clinical and sub-clinical levels, are at higher risk for several negative outcomes. The current paper reports the results from a randomized clinical trial evaluating an adaptation of the Coping Power for preschool-aged children. In the present study, Coping Power is adapted as a universal prevention intervention, in which teachers deliver a curriculum that is designed to improve children's social competence and reduce problem behaviours.

METHODS

Ten nursery school classes (164 children, mean age 54.40 months) from two Italian schools were randomly assigned to Coping Power or to the control group, which received the standard academic curriculum provided in Italian nursery schools. Teachers in the five intervention classes implemented weekly lessons and extension activities over a 6-month period. Teacher and parent reports of child behaviour assessments were collected at the beginning and end of the school year. At each assessment period, teachers completed the Strengths and Difficulties Questionnaire.

RESULTS

The findings suggest that after exposure to Coping Power, intervention children showed lower levels of behavioural difficulties, rated both by parents and teachers.

CONCLUSIONS

The results of this study are promising and can be interpreted as providing initial support for the efficacy of the preschool version of Coping Power.