School-based aggression is one of the best known predictors of future academic, social, and psychological adjustment problems including poor school achievement, dropping out of school, delinquency, peer rejection, peer victimization, and depression. Until recently; however, research on aggression has been seriously limited in two important ways: (1) aggressive boys have received most of the research attention whereas aggressive girls have often been excluded from relevant studies; and (2) forms of aggression that are salient to boys, such as threatened or actual physical harm, have been emphasized whereas forms that are salient for girls, such as threats to end the friendship or the use of the "silent treatment," have largely been ignored. Because of these limitations, relatively little is known about girls who are aggressive at school, which impedes understanding of the adjustment difficulties of girls in general. The proposed study will address this gender inequity by targeting types of aggressive behaviors salient for females (relational aggression) as well as those more characteristic of males (physical aggression). This research will examine links between aggression and autonomic nervous system activity (blood pressure, heart rate, and skin conductance), an index of stress physiology, for a sample of 250 4th graders. This sample will be followed prospectively for two years with reassessments occurring in 5th and 6th grades. Of particular interest will be identification of patterns of reactivity to various types of social stressors and their links to relational and/or physical aggression for boys versus girls. Findings from the proposed research have significant promise for substantially increasing the knowledge of the factors that contribute to the development and maintenance of relational and physical aggression. First, very little is known about the biological risk factors associated with relational aggression. Information about the biological contributors to both relational and physical aggression would improve the ability to identify children most at risk for long-term behavior problems as well as those at risk for future health problems. Although not typically considered in past studies of stress physiology and childhood aggression, relatively high levels of physiological reactivity to stressors, particularly those of an interpersonal nature, have been shown to place individuals at risk for serious health problems such as heart disease or immune dysfunction. Because this risk can begin at relatively young ages and persist over time, early identification is likely to play an important role in the prevention of these serious health problems. Findings from the proposed study are also likely to have important implications for increasing the specificity of intervention efforts with aggressors. If particular forms of aggression (relational vs. physical) are shown to be associated with physiological underarousal, intervention efforts may focus on helping aggressors to identify more appropriate, socially competent ways of seeking out stimulation in their environments. In contrast, aggressors who exhibit physiological overarousal in response to stress may benefit from programs that include anger management techniques, including recognition of physiological responses.
The goal of this grant was to examine the association between functioning of one of the body’s stress systems, the autonomic nervous system (ANS), and children’s aggressive behavior. The project focused specifically at expanding our understanding of how physiological stress reactivity, such as increases in heart rate following stress, relate to relational forms of aggression. Relational aggression, defined as behaviors intended to hurt or harm others through the damage of interpersonal relationships, includes behaviors such as maliciously spreading gossip or using social exclusion. Relational aggression is more common among girls than physical forms of aggression, such as hitting. This project examined how stress system functioning related to both physical and relational forms of aggression. We also examined the role of gender and of being the target of aggression (i.e., victimization) in the relation between stress system activity and aggression. Our findings indicated that relational aggression in girls appeared to most frequently occur in the context of blunted stress reactivity (e.g., blunted heart rate reactions to stress). In contrast, among boys, relational aggression was associated with heightened stress reactivity (e.g., high heart rate reactions to stress). Our findings highlight the possibility that aggression, especially relational forms of aggression in girls, may be most common among youth who fail to experience emotional arousal in response to peer stress. Instead of being anger-prone, these aggressive youth may be relatively unemotional. Among boys, relational aggression may often emerge among youth who experience exaggerated angry reactions to peer stress. In both boys and girls, stress reactivity was primarily a risk factor for aggression among youth who were themselves often the targets of peer aggression. The findings from this study have significant societal implications and may inform interventions developed for aggressive boys and girls. Results highlight the role of victimization experiences in the development of aggression among youth with dysregulated stress reactions. These findings suggest that one potential intervention point for aggressive conduct in schools is to prevent victimization of at-risk youth (e.g., youth with disruptions in stress reactivity). Findings also underscore the role of unemotional reactions to peer stress in the development of aggression, suggesting that intervention efforts that focus on anger management may benefit from broadening the focus to other emotional processes, with a particular emphasis on unemotional reactions to peer stress. The results also suggest that risk factors for aggression may differ for males versus females and for physical versus relational aggression, highlighting the need for the development of interventions aimed at reducing relational aggression in females.
