Changes In Physical Aggression Research Articles

Peer Factors as Mediators of Relations Between Exposure to Violence and Physical Aggression in Middle School Students in a Low-Income Urban Community.

Although prior research has demonstrated that peers influence both physical aggression and exposure to violence during adolescence, few studies have investigated the extent to which peers play a role in relations between physical aggression and violence exposure. This longitudinal study examined peer pressure for fighting, friends' delinquent behavior, and friends' support for fighting as mediators of relations between exposure to violence through witnessing and victimization, and adolescents' frequency of physical aggression. Participants were 2,707 adolescents attending three urban middle schools (Mage = 12.4; 52% female; 79% African American, 17% Hispanic/Latino). Participants completed measures of their frequency of physical aggression, witnessing community violence, victimization by violence, and negative life events, and peer variables at four waves within the same school year. Cross-lagged analyses indicated that the role of peer variables as mediators varied as a function of the type of exposure and the direction of effects. Whereas peer pressure for fighting mediated relations between witnessing violence and changes in physical aggression, friends' delinquent behavior mediated relations between physical aggression and changes in witnessing violence and victimization. In contrast, violent victimization was not associated with changes in any of the peer factors when included in the same model as witnessing violence. These findings highlight the role of peers as both a cause and a consequence of adolescents' aggressive behavior and exposure to violence. They suggest focusing on peer variables as targets for interventions to disrupt connections between exposure to violence and physical aggression during early adolescence.

The influence of exposure to violence on adolescents’ physical aggression: The protective influence of peers

IntroductionThis study examined the degree to which peers can serve as a protective factor to mitigate the negative effects of exposure to violence (i.e., victimization, witnessing violence) on adolescents' physical aggression. Four specific dimensions of peer influence were examined — friends' support for nonviolence, friends' support for fighting, peer pressure for fighting, and friends’ delinquent behavior. MethodsAnalyses were conducted on four waves of data collected every 3 months (i.e., fall, winter, spring, summer) from a predominantly African-American (78%) sample of 2575 sixth, seventh, and eighth graders attending three public middle schools in the United States. The sample was 52% female, with a mean age of 12.3 years (SD = 1.00). ResultsFindings for relations with victimization differed by sex. For boys, low levels of friends' delinquent behavior attenuated the relation between victimization and changes in physical aggression across all three waves. The protective effect of low levels of peer pressure for fighting was only evident in the winter for boys, whereas the protective effect of friends' support for nonviolence was only evident in the summer. For girls, high levels of friends’ support for nonviolence attenuated the relation between victimization in the winter and changes in physical aggression in the spring. In contrast, none of the peer factors moderated the relation between witnessing violence and physical aggression. ConclusionsFindings suggest that prevention and interventions that increase positive peer influences and decrease negative peer influences may benefit adolescents by reducing risks associated with victimization.

Bidirectional Relations between Witnessing Violence, Victimization, Life Events, and Physical Aggression among Adolescents in Urban Schools.

Although there is empirical evidence supporting associations between exposure to violence and engaging in physically aggressive behavior during adolescence, there is limited longitudinal research to determine the extent to which exposure to violence is a cause or a consequence of physical aggression, and most studies have not addressed the influence of other negative life events experienced by adolescents. This study examined bidirectional relations between physical aggression, two forms of exposure to violence-witnessing violence and victimization, and other negative life events. Participants were a sample of 2568 adolescents attending three urban public middle schools who completed measures of each construct every 3 months during middle school. Their mean age was 12.76 (SD = 0.98); 52% were female. The majority were African American (89%); 17% were Hispanic or Latino/a. Cross-lagged regression analyses across four waves of data collected within the same grade revealed bidirectional relations between witnessing violence and physical aggression, and between witnessing violence and negative life events. Although physical aggression predicted subsequent changes in victimization, victimization predicted changes in physical aggression only when witnessing violence was not taken into account. Findings were consistent across sex and grades. Overall, these findings highlight the need for interventions that break the connection between exposure to violence and aggression during adolescence.

Evaluation of the Olweus Bully Prevention Program in an Urban School System in the USA.

This study evaluated the Olweus Bully Prevention Program (OBPP) in urban middle schools serving a mostly African American student population. Participants were 1791 students from three communities with high rates of crime and poverty. We evaluated the impact of the OBPP using a multiple-baseline experimental design in which we randomized the order and timing of intervention activities across three schools. We assessed the frequency of violence and victimization using self-report and teachers' ratings of students collected every 3months over 5years. Initiation of the OBPP was associated with reductions in teachers' ratings of students' frequency of aggression, with effects emerging in different years of implementation for different forms of aggression. Whereas reductions in teachers' ratings of students' verbal and relational aggression and victimization were evident during the second implementation year, reductions in physical aggression did not appear until the third year. Effects were consistent across gender and schools, with variability across grades for relational and verbal aggression and victimization. In contrast, there were no intervention effects on students' reports of their behavior. Positive outcomes for teachers', but not students' ratings, suggest the intervention's effects may have been limited to the school context. Variation in when effects emerged across outcomes suggests that changes in physical aggression may require more sustained intervention efforts. The intervention was also associated with increases in teachers' concerns about school safety problems, which may indicate that teachers were more attuned to recognizing problem behaviors following exposure to the OBPP.

Peer Effects on Aggressive Behavior in Norwegian Child Care Centers.

This study examined whether exposure to changes in peer aggression predicted changes in child physical aggression (PA) in preschool children attending Norwegian Early Childhood Education and Care (ECEC) centers. Data from the Behavior Outlook Norwegian Developmental Study were used, including 956 children. In fixed effects models, within-child changes in exposure to peer aggression predicted changes in teacher-rated child PA across ages 2, 3, and 4. Moreover, changes in exposure to a peer group with two or more externalizing children increased teacher-rated child PA over time, but only for boys. No significant peer effects on parent-rated child PA were found. Findings point to the importance of avoiding the congregation of several problematic children, particularly boys, in the same ECEC groups.

Reducing child aggression through sports intervention: The role of self-control skills and emotions

This study examined how sports intervention may reduce aggressive behaviors in children (Grades 3–6), focusing on the relations between acquisition of self-control skills (SCSs) and aggressive behavior through the mediation of thoughts (i.e., hostility) and emotions (i.e., positive and negative). In a sample of 649 Israeli children, 50% were assigned to an experimental group and the remainder to a waitlisted control group. As hypothesized, children in the experimental group reported significantly larger gains in SCSs and significantly larger decreases in physical aggression, hostile thoughts, and negative emotions. Results of structural equation modeling suggested that SCS gains were linked to changes in hostile thoughts, as mediated by changes in both positive and negative emotions. In addition, changes in hostile thoughts were linked to changes in physical aggression through the mediation of changes in anger. Among girls, changes in SCSs were linked directly to changes in physical aggression (with no indirect effect), whereas among boys, changes in SCSs were linked indirectly to changes in physical aggression, through changes in positive and negative emotions. Findings contribute to understanding of possible mechanisms underlying the associations between children's self-control and aggression, with particular implications for the roles of positive and negative emotions.

The Impact of Victimization and Witnessing Violence on Physical Aggression Among High‐Risk Adolescents

Relations among witnessing violence, victimization, and physical aggression were investigated within a high-risk sample of 1,156 sixth graders. Longitudinal, multilevel analyses were conducted on two waves of data from two cohorts of students in 37 schools from four communities. The sample was 65% male and 67% African American. Neighborhood concentrated disadvantage, witnessing violence, victimization, and physical aggression were strongly and positively correlated at the school level. Contrary to hypothesis, exposure to violence did not mediate the effects of neighborhood concentrated disadvantage on changes in physical aggression. As expected, witnessing violence and physical aggression had bidirectional longitudinal effects on each other at the student level. In contrast, there were no cross-variable relations between changes in violent victimization and aggression over time.

Infant externalizing behavior as a self-organizing construct.

We evaluated the extent to which the externalizing behavior construct is self-organizing in the first 2 years of life. Based on dynamic systems theory, we hypothesized that changes in physical aggression, defiance, activity level, and distress to limitations would each be predicted by earlier manifestations of one another. These hypotheses were evaluated via mothers' and fathers' reports of 274 infants' externalizing behaviors at 8, 15, and 24 months of child age. Eight-month measures of physical aggression, activity level, and/or distress to limitations explained increases in physical aggression, defiance, activity level, and distress to limitations from 8 to 15 months. Increases in defiance and activity level from 15 to 24 months were predicted by 15-month physical aggression and/or distress to limitations. These findings suggest that the externalizing behavior construct is formed by dynamic interplay among its individual elements, particularly between 8 and 15 months.

Developmental trajectories of physical aggression: prediction of overt and covert antisocial behaviors from self- and mothers' reports.

Physical aggression declines for the majority of children from preschool to elementary school. Although this desistance generally continues during adolescence and early adulthood, a small group of children maintain a high level of physical aggression over time and develop other serious overt and covert antisocial behaviors. Typically, researchers have examined relations of developmental changes in physical aggression to later violence with teachers' or mothers' reports on surveys. Little is known about the degree to which children's self-reported physical aggression predicts later antisocial behavior. The longitudinal study in this article had a staggered, multiple cohort design. Measures of physical aggression were collected through self- and mother reports from age 11-14 years, which were used to construct trajectory groups (attrition was 6 and 14% from age 11-14, respectively, for self- and mother reports). Overt and covert antisocial behaviors were self-reported at age 18-19 years (attrition was 36% from age 11 to 18-19). Four trajectory groups (low stable, 11%; moderate-low declining, 34%; moderate declining, 39%; high stable, 16%) were identified from self-reports, whereas three trajectories (low declining, 33%; moderate declining, 49%; high stable, 18%) were identified from mothers' ratings. We examined the prediction of overt and covert antisocial behaviors in early adulthood from the high stable and the moderate declining trajectories. According to both informants, higher probability of belonging to the high stable group was associated with higher overt and covert antisocial behavior, whereas higher probability of belonging to the moderate declining group was associated with higher covert antisocial behavior. Our results support the value of children's as well as mothers' reports of children's aggression for predicting different types of serious antisocial behavior in adulthood.

A Brief Motivational Intervention for Physically Aggressive Dating Couples

Motivational interviewing is a brief non-confrontational intervention designed to enhance motivation to reduce harmful behavior (Miller and Rollnick 2002). The purpose of this study was to examine the effectiveness of motivational interviewing as a targeted prevention approach for partner aggression in emerging adulthood. Participants were 50 college dating couples between 18 and 25 years old who reported at least one act of male-to-female physical aggression in their current relationships. After completing a 2-hour assessment session, half of all couples were randomly assigned to a 2-hour individualized motivational feedback session targeting physical aggression and risk factors for aggression. The remaining couples received minimal, non-motivational feedback. Follow-up surveys were conducted 3, 6, and 9 months later. Hierarchical linear modeling analyses indicated that, compared to the control condition, the motivational feedback intervention led to reductions in physical aggression and harmful alcohol use and to less acceptance of female psychological aggression and male psychological aggression (among women only). Lagged analyses indicated that changes in physical aggression were predicted by reductions in psychological aggression and by lower acceptance of both male and female psychological aggression. Reductions in physical aggression predicted lower anxiety and greater relationship investment and male relationship commitment over time. These findings suggest that a brief motivational intervention is a useful prevention approach for high-risk dating couples, with benefits to both individual and relationship functioning.

Using a vulnerability-stress-adaptation framework to predict physical aggression trajectories in newlywed marriage.

The authors used a vulnerability-stress-adaptation framework to examine personality traits and chronic stress as predictors of the developmental course of physical aggression in the early years of marriage. Additionally, personality traits and physical aggression were examined as predictors of the developmental course of chronic stress. Data from 103 couples collected 4 times over the first 3 years of marriage were analyzed with an actor-partner interdependence model and structural equation modeling techniques. Personality traits of husbands predicted their own physical aggression and stress trajectories, as well as their wives' levels of stress and physical aggression. Personality traits of wives predicted their levels of stress and physical aggression and predicted changes in their physical aggression over time. Both husbands' and wives' changes in stress predicted changes in physical aggression over time. Implications for employment of a vulnerability-stress-adaptation model in the study of physical aggression and for improvement of the efficacy of therapies targeting physical aggression in intimate relationships are delineated.

The effect of fish oil on physical aggression in schoolchildren — a randomized, double-blind, placebo-controlled trial

Objectives The aim of the study was to investigate whether fish oil supplementation affected Japanese schoolchildren's behavior, with changes in aggression over time as the primary endpoint. Design and subjects A placebo-controlled double-blind study with 166 schoolchildren 9–12 years of age was performed. The subjects of the fish oil group ( n=83) took fish oil-fortified foods (bread, sausage and spaghetti). These foods were provided in amounts such that each subject in the fish oil group had an intake of 3600 mg of docosahexaenoic acid + 840 mg of eicosapentaenoic acid (EPA)/week for 3 months. The rest (the controls, n=83) took control supplements. At the start and end of the study, psychological tests were performed to assess their aggression. Results Physical aggression assessed by Hostility-Aggression Questionnaire for Children in girls increased significantly (median: 13 to 15, n=42) in the control group and did not change (13 to 13, n=43) in the fish oil group with a significant intergroup difference ( P=.008) with baseline as covariate. The changes in physical aggression scores over time and those of the ratio of EPA/arachidonic acid in RBC (ΔEPA/AA) were significantly correlated in girls who agreed to blood collection ( r=−.53, P=.01, n=23). On the contrary, there were no significant changes in physical aggression in boys. Aggression against others (extraggression) assessed by Picture Frustration Study did not change in the control group (median: 5 to 5) but increased significantly in the fish oil group (4 to 5) with a significant intergroup difference ( P=.02) with baseline as covariate. These changes in extraggression might be explained partly by significantly lower baseline values of extraggression in the fish oil group ( P=.02) than in the control group. There were no significant correlations between Δextraggression and ΔEPA/AA in blood-sampled children ( n=49). Impulsivity of girls assessed by parents/guardians using the diagnostic criteria for attention deficit/hyperactivity disorder of DSM-IV was reduced in the fish oil group (1 to 0) with a significant ( P=.008) intergroup difference from the control group (1 to 1). There were no significant correlations between Δimpulsivity and ΔEPA/AA in blood-sampled girls. In males, impulsivity reduced in both groups without any intergroup differences. Conclusion There is a possibility that changes in fatty acid nutrition might affect physical aggression especially in girls.