Linkages Between Children's and Their Friends' Social and Physical Aggression: Evidence for a Gene–Environment Interaction?

Based on a sample of 406 seven-year-old twins, this study examined whether exposure to friends' social or physical aggression, respectively, moderates the effect of heritability on children's own social and physical aggression. Univariate analyses showed that children's own social and physical aggression were significantly explained by genetic factors, whereas friends' social and physical aggression represented "true" environmental factors that were unrelated to children's genetic dispositions. Multivariate analyses further suggested a possible gene–environment interaction in the link between friends' and children's physical aggression but not in the link between friends' and children's social aggression. Instead, friends' social aggression was directly related to children's social aggression, in addition to genetic effects on this behavior. Theoretical and practical implications of these results are discussed.     

Linkages between children's and their friends' social and physical aggression: evidence for a gene-environment interaction?

Based on a sample of 406 seven-year-old twins, this study examined whether exposure to friends' social or physical aggression, respectively, moderates the effect of heritability on children's own social and physical aggression. Univariate analyses showed that children's own social and physical aggression were significantly explained by genetic factors, whereas friends' social and physical aggression represented "true" environmental factors that were unrelated to children's genetic dispositions. Multivariate analyses further suggested a possible gene-environment interaction in the link between friends' and children's physical aggression but not in the link between friends' and children's social aggression. Instead, friends' social aggression was directly related to children's social aggression, in addition to genetic effects on this behavior. Theoretical and practical implications of these results are discussed.     

The importance of shared environment in mother-infant attachment security: a behavioral genetic study

In a sample of 157 monozygotic and dizygotic twins, genetic and environmental influences on infant attachment and temperament were quantified. Only unique environmental or error components could explain the variance in disorganized versus organized attachment as assessed in the Ainsworth Strange Situation Procedure. For secure versus nonsecure attachment, 52% of the variance in attachment security was explained by shared environment, and 48% of the variance was explained by unique environmental factors and measurement error. The role of genetic factors in attachment disorganization and attachment security was negligible. Genetic factors explained 77% of the variance in temperamental reactivity, and unique environmental factors and measurement error explained 23%. Differences in temperamental reactivity were not associated with attachment concordance.     

The genetic and environmental covariation among psychopathic personality traits, and reactive and proactive aggression in childhood

The present study investigated the genetic and environmental covariance between psychopathic personality traits with reactive and proactive aggression in 9- to 10-year-old twins (N = 1,219). Psychopathic personality traits were assessed with the Child Psychopathy Scale (D. R. Lynam, 1997), while aggressive behaviors were assessed using the Reactive Proactive Questionnaire (A. Raine et al., 2006). Significant common genetic influences were found to be shared by psychopathic personality traits and aggressive behaviors using both caregiver (mainly mother) and child self-reports. Significant genetic and nonshared environmental influences specific to psychopathic personality traits and reactive and proactive aggression were also found, suggesting etiological independence among these phenotypes. Additionally, the genetic relation between psychopathic personality traits and aggression was significantly stronger for proactive than reactive aggression when using child self-reports.     

Development pathways from abusive parenting to delinquency: The mediating role of depression and aggression

This study investigated the long-term relationship between abusive parenting and adolescent mental health, and the path to delinquent behavior. Longitudinal data from 5th through 7th graders from the Korean Children and Youth Panel Survey (KCYPS) were analyzed to examine if abusive parenting was a predictor of early adolescent delinquency behavior, via aggression and depression as mediating factors. The results were as follows. First, parental abuse (both emotional and physical) was found to have significant effects on children's psychosocial factors (aggression and depression), while parental neglect (both emotional and physical) had significant effects on depression alone and not on aggression. Second, aggression exerted significant effects on both violent and non-violent delinquent behaviors, while depression had a significant effect on only non-violent delinquent behaviors. Third, children's psychosocial factors (aggression and depression) played significant mediating roles between earlier abusive parenting and delinquent behaviors. Fourth, for children living in a family with their grandparents, paths from abusive parenting, psychosocial adaptation, and later delinquent behaviors were not significant, implying that living with grandparents played a protective factor in these relationships.     

Adolescent, parent, and observer perceptions of parenting: genetic and environmental influences on shared and distinct perceptions

Agreement among reporters on features of family life, whether family members or outside observers, is considered to be low. This study, which involved a national sample of 720 families comprised of identical and fraternal twins, full siblings, half siblings, and biologically unrelated stepsiblings, examined the issue of low interrater agreement by decomposing the common and unique variance among parent, child, and observer reports of parenting behaviors (warmth and negativity) into genetic and environmental factors. Quantitative genetic analyses were employed to decompose the "Social" level of perception (common variance among parents, children, observers), the level of "Family" subculture (common variance only among parents and children), and the unique "Individual" level into genetic and environmental components. It was predicted that genetic factors would account for substantial portions of the variance at the Social and Family levels; nonshared environmental factors were expected to influence variance unique to child reports; and shared environmental factors were expected to influence variance unique to parent reports. A second and related aim of the study was to examine the subjective-objective dimension of genetic effects on measures of the environment. Results of model-fitting analyses generally supported the predictions for parental warmth and negativity at the Family and Individual levels. At the Social level, genetic factors were predominant for parental negativity and shared environmental factors for parental warmth. The findings are discussed in terms of genetically influenced child effects on parenting and methodological difficulties in constructing latent variables.     

Gene-environment processes linking aggression, peer victimization, and the teacher-child relationship

Aggressive behavior in middle childhood is at least partly explained by genetic factors. Nevertheless, estimations of simple effects ignore possible gene-environment interactions (G × E) or gene-environment correlations (rGE) in the etiology of aggression. The present study aimed to simultaneously test for G × E and rGE processes between aggression, on the one hand, and peer victimization and the teacher-child relationship in school, on the other hand. The sample comprised 124 MZ pairs and 93 DZ pairs assessed in Grade 1 (mean age = 84.7 months). Consistent with rGE, children with a presumed genetic disposition for aggression were at an increased risk of peer victimization, whereas in line with G × E, a positive relationship with the teacher mitigated the genetically mediated expression of aggression.     

Longitudinal genetic study of verbal and nonverbal IQ from early childhood to young adulthood

In a longitudinal genetic study we explored which factors underlie stability in verbal and nonverbal abilities, and the extent to which the association between these abilities becomes stronger as children grow older. Measures of verbal and nonverbal IQ were collected in Dutch twin pairs at age 5, 7, 10, 12 and 18 years. The stability of both verbal and nonverbal abilities was high, with correlations over time varying from .47 for the 13-year time interval up to .80 for shorter time intervals. Structural equation modeling showed increasing heritability with age, from 48% (verbal) and 64% (nonverbal) at age 5 to 84% and 74% at age 18. Genetic influences seemed to be the driving force behind stability. Stability in nonverbal ability was entirely explained by genes. Continuity in verbal abilities was explained by genetic and shared environmental effects. The overlap between verbal and nonverbal abilities was fully accounted for by genes influencing both abilities. The genetic correlation between verbal and nonverbal IQ increased from .62 in early childhood to .73 in young adulthood.     

Early Child Language Mediates the Relation Between Home Environment and School Readiness

Home environment quality is a well-known predictor of school readiness (SR), although the underlying processes are little known. This study tested two hypotheses: (a) child language mediates the association between home characteristics (socioeconomic status and exposure to reading) and SR, and (b) genetic factors partly explain the association between language and SR. Data were collected between 6 and 63 months in a large sample of twins. Results showed that home characteristics had direct effects on SR and indirect effects through child language. No genetic correlation was found between language and SR. These results suggest that home characteristics affect SR in part through their effect on early language skills, and show that this process is mainly environmental rather than genetic in nature.     

The rates and correlates of the exposure of Palestinian adolescents to family violence: toward an integrative-holistic approach

OBJECTIVES: First, to examine the rates of Palestinian adolescents' exposure to (i.e., witnessing and experiencing) different patterns of psychological aggression and physical violence in their families of origin; and second, to examine the correlation between this exposure and sociodemographic characteristics, parents' psychological adjustment problems, and family exposure to political stressors. METHOD: A cross-sectional survey was carried out among a sample of 1,185 Palestinian secondary school students. RESULTS: The study reveals very alarming rates of witnessing interparental and parent-to-sibling aggression and violence, and high rates of experiencing aggression and violence by parents and siblings during childhood and adolescence. In addition, these rates were found to be intercorrelated, and correlated significantly with several sociodemographic characteristics such as parents' levels of education, place of residence, family size, religious affiliation, family income, and housing conditions, as well as with parents' psychological adjustment problems and with family exposure to political stressors. CONCLUSIONS: The results of the study reveal strong evidence that emphasizes the importance of studying violence in the family from an integrative, comprehensive, and ecological perspective that incorporates intrapersonal traits, family stress theory, family resources theory, social learning theory, and sociological and environmental factors, to explain the risk factors and predictors of violence in the family.     

Dynamic and static assessment of phonological awareness in preschool: a behavior-genetic study

The genetic and environmental overlap between static and dynamic measures of preschool phonological awareness (PA) and their relation to preschool letter knowledge (LK) and kindergarten reading were examined using monozygotic and dizygotic twin children (maximum N = 1,988). The static tests were those typically used to assess a child's current level of PA such as blending and elision, and the dynamic test included instruction in phoneme identity to assess the child's ability to respond to this instruction. Both forms were influenced by genes and by shared and nonshared environment. The static and dynamic versions were influenced by the same genes, and part of the total genetic influence was shared with LK. They were subject to both overlapping and independent shared environment influences, with the component in common also affecting LK. Nonshared environment influences were mostly independent. Scores from dynamic assessment added only minimally to variance explained in kindergarten reading after LK and static assessment had been factored in. Although one of the genetic factors that influenced both forms of PA also affected kindergarten reading, it was only the one shared with LK. The authors conclude that dynamic assessment of PA in preschool offers little advantage over the more commonly used static forms, especially if LK scores are available, although they acknowledge its potential in cases of preschool educational disadvantage.     

Deaf children and bullying: directions for future research

U.S. SCHOOLS are currently addressing bullying and its effects on children. Bullying is characterized as repetitive verbal teasing, threatening, physical intimidation, demeaning others, violent acts, torture, and other forms of verbal and physical aggression (Smith and Sharp, 1994a). Little is known about bullying and its impact on deaf children. Measures to describe and quantify bullying factors in this population should be developed and validated that address characteristics of deaf victims and bullies, various types of school settings deaf children attend, bullying dynamics that may be unique to this population and its peers, and other environmental factors. The presence of disabilities besides deafness, social support systems of deaf children and their families, sociocultural background, degree of hearing loss, parental educational levels and occupations, socioeconomic status, and linguistic backgrounds should also be considered. This discussion highlights issues and precautions concerning future directions for studying bullying with deaf children.     

LINKING SOCIAL–ENVIRONMENTAL RISK FACTORS WITH AGGRESSION IN SUBURBAN ADOLESCENTS: THE ROLE OF SOCIAL–COGNITIVE MEDIATORS

Previous research suggests that social–cognitive factors mediate the association between social–environmental risk and aggression in high‐risk samples, but less is known about the relation among these factors in suburban youth. The present study examined whether such an association occurred for suburban youth exposed to low levels of social rejection and community violence. Using data from 184 adolescents (mean age = 14.97 years, SD = .84) and their homeroom teachers, analyses with structural equation modeling revealed a significant relation between relatively mild levels of social–environmental risk and aggression. This association was partially mediated by negatively biased social–cognitive factors (i.e., general knowledge structures and social information processing). Findings suggest that even relatively low levels of social rejection and community violence exposure characterizing suburban youth (in contrast to urban youth) put them at an increased risk for problems with aggression.     

Telephone Testing and Teacher Assessment of Reading Skills in 7-year-olds: II. Strong Genetic Overlap

In a companion paper, word recognition skills assessed by telephone using the Test of Word Reading Efficiency (TOWRE) were found to correlate highly with National Curriculum (NC) teacher-assessed reading ability in 7-year-old twins. This study examined the genetic and environmental origins of this high correlation. TOWRE and NC scores were both highly heritable and the correlation between them was largely due to overlapping genetic effects. These findings were obtained both across the normal range of reading abilities and at the low extreme, defined by scores below a 13.4% cut-off on either measure. TOWRE and NC scores may provide promising phenotypes for further study of the aetiology of early reading abilities and disabilities.     

Intelligence and Achievement: A Behavioral Genetic Perspective

Understanding the etiology and relationship between standardized intelligence and academic achievement tests is essential, given their ever-increasing role in American education. Behavioral genetic studies have examined the genetic and environmental etiology of intelligence, academic achievement, and their relationship. Results suggest that genetic, shared environmental, and nonshared environmental influences have an impact on intelligence and academic achievement. Behavioral genetic studies also suggest that the importance of genes may vary as a function of age. Other studies suggest that genes drive the correlation and that the nonshared environment drives the discrepancy between measures of intelligence and achievement. Implications for the identification of intellectually and academically relevant environmental influences are discussed.     

Gene–environment interplay linking perceived parental supervision and peer drunkenness with Chinese adolescent alcohol initiation

Following 602 Chinese twin pairs (48% male, all Han ethnicity) from primarily lower-than-average socioeconomic status families from early to mid-adolescence (M_s = 12 and 15 in 2006 and 2009), this study investigated gene–environment interplay between perceived parental supervision, peer drunkenness, and adolescent alcohol initiation. For alcohol initiation, shared environmental influences were initially negligible but became substantial. Genetic factors largely explained the links between both correlates with alcohol initiation. Parental supervision amplified genetic risks for alcohol initiation in early adolescence but suppressed it in mid-adolescence. Peer drunkenness augmented genetic and environmental influences at both times. Peer drunkenness showed stronger links and moderating potential than parental supervision. Chinese adolescents show dynamic gene–environment interplay patterns involving parent–child and peer processes in alcohol initiation.     

Effects of parental verbal aggression on children's self-esteem and school marks.

OBJECTIVE: The aim of the study was to distinguish the effects of verbal aggression from those of physical aggression and investigate whether parental verbal violence has negative effects on children's self-esteem and academic achievements. METHOD: One hundred and forty-four 10-year-old children completed the Harter Self-perception Profile for Children questionnaire and a questionnaire concerning their mothers' and fathers' verbal aggression towards them and their use of physical punishment. The researchers used school records to obtain the subjects' marks in French (their native language) and Mathematics. RESULTS: Six children had never been the targets of either verbal aggression or physical punishment. Thirty-four children had been subjected to both types of aggression. Verbal aggression alone was found to be in significant negative correlation with three of six components of self-esteem. Verbal aggression alone was also found to be in significant negative correlation with French marks. In addition children who had been subject to greater verbal aggression had lower self-esteem and lower marks in French than children who had been subject to lesser verbal aggression. They were also significantly negatively affected in a fourth component of self-esteem. CONCLUSIONS: Parental verbal aggression alone as separate and distinct from physical punishment contributes to lowering children's self-esteem and school achievements. Given the extent of the use of verbal aggression by ordinary parents the authors suggested a need for parent education on the topic of positive methods of child rearing.     

Aggression in primary schools: the predictive power of the school and home environment

In this study, we analyse the predictive power of home and school environment-related factors for determining pupils’ aggression. The multiple regression analyses are performed for fourth- and eighth-grade pupils based on the Trends in Mathematics and Science Study (TIMSS) 2007 (N = 8394) and TIMSS 2011 (N = 9415) databases for Slovenia. At the national level, the Lestvica agresivnosti aggression scale was administered in both TIMSS cycles. For home environment variables, we included those related to socio-economic status, pupils’ educational aspirations, parental activities with their children and pupils’ free time activities. The results show that the variables related to socio-economic status, spare time activities and parental activities are significant predictors. The results differ in both analysed data-sets. For school environment variables, we include those related to the school climate, pupils’ attitudes towards school and school subjects and pupils’ achievement in mathematics. We find that the variables related to school climate and students’ self-confidence are significant predictors. These results are stable in both years. The predictive power of the school characteristics model (including only the school environment variables) is larger (based on the proportion of explained variance) compared with the home characteristics model. The hierarchical linear model of data from 2007 to 2011 shows small differences in aggression between schools. The inclusion of two data cycles collected in two time- periods allows us to observe changes in aggression predictors over time. Practical implications are finally included.     

"Somebody Else Making Somebody Else Fight": Aggression and the Social Context Among Urban Adolescent Girls

This study explored episodes of social and physical aggression among members of a low-income, urban sample of adolescent girls. Thirty African American, Hispanic, and Latina girls were interviewed about recent episodes of conflict, disagreement, or fighting in their grade. The study explored (a) the relationship between episodes of physical aggression and social aggression, (b) the importance of group alliances during aggressive episodes, and (c) the resolution of social and physical aggression. Episodes of social aggression frequently led to episodes of physical aggression among these girls, with group alliances solidified in the process. Adults intervened to resolve episodes of physical aggression (using suspension from school), whereas precipitating episodes of social aggression remained unresolved. Adolescents reported that suspension was an acceptable form of conflict resolution.     

The incidence of witnessing interparental violence and some of its psychological consequences among Arab adolescents

OBJECTIVES: The study had two aims. First, it sought to examine the incidence of interparental psychological aggression and physical violence witnessed by Arab adolescents. Second, it sought to assess the implications of such exposure on adolescents' feelings of hopelessness, psychological adjustment problems, and self-esteem. METHOD: A cross-sectional survey was conducted among a sample of 1640 Arab adolescents from Israel. Different forms of the Conflict Tactics Scales (CTS) were utilized to measure the extent of interparental psychological aggression and physical violence witnessed by adolescents. The Hopelessness Scale for Children (HSC), the Psychological Adjustment Scale (PAS), and the Rosenberg Self-Esteem Scale (RSE) were used to measure the above-mentioned psychological states. RESULTS: The results indicate that Arab adolescents witness high rates of psychological aggression and physical violence between their parents. Furthermore, regression and multiple regression analyses revealed that significant amounts of the variance in adolescents' hopelessness, psychological adjustment problems, and low self-esteem are explained by witnessing different patterns of interparental psychological aggression and physical violence, beyond the amounts of variance in these criterion variables that can be attributed to some sociodemographic characteristics of the adolescents, their parents, and families. CONCLUSIONS: The results provided strong support for the hypothesis that witnessing interparental aggression and violence has a strong detrimental impact on adolescents' psychological states. Furthermore, the results emphasize the need for further research into the effects of witnessing other patterns of psychological aggression and physical violence in adolescents' nuclear and extended families. It would also be worthwhile to investigate the risk factors that predispose violence in the family and the consequences of those factors.