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

Sex differences in relational and overt aggression among 3rd (n=176), 4th (n=179), and 5th graders (n=145) from three public schools (n=500; 278 girls) were examined. Nominations of relational aggression increased over time among 4th and 5th grade girls, but not among boys or 3rd grade girls. Among 3rd graders, boys received more nominations for relational aggression than girls. By the end of the 5th grade, girls received more relational aggression nominations than boys. There was also a significant rise in nominations of overt aggression among 5th grade girls, but not among 5th grade boys or younger boys and girls. As expected, boys were more likely than girls to be nominated for overt aggression at all grade levels. The findings are helpful for explaining inconsistencies of earlier research pertaining to sex differences in relational aggression and for advancing our understanding of the causes of aggression. Aggr. Behav. 36:282–291, 2010. © 2010 Wiley‐Liss, Inc.     

Beliefs about aggression among male and female prisoners

This study investigated instrumental and expressive beliefs about aggression, and their association with self-reported aggression, among male (N = 62) and female (N = 47) prisoners serving sentences in closed prisons in the North of England. Instrumental but not expressive beliefs were strongly correlated with measures of aggression. Expressive beliefs were significantly higher among females than males, but unlike previous findings, there were no significant sex differences in instrumental beliefs or in physical aggression. However, age was significantly negatively correlated with instrumental beliefs, physical aggression, anger and hostility. Those convicted for violent offences showed significantly higher scores for physical aggression and anger, but lower scores for expressive beliefs. The results provide both similarities and contrasts with previous findings for student samples. Aggr. Behav. 23:405–415, 1997. © 1997 Wiley-Liss, Inc.     

Comparison of two aggression inventories

Two recently developed questionnaire measures of aggression, the Aggression Questionnaire [Buss and Perry (1992; Journal of Personality and Social Psychology 63:452–459]; and the Aggression Inventory [Gladue (1991a); Psychological Reports 68:675–684], were administered to a British sample (N=320) of men and women undergraduates. Both questionnaires contain subscales measuring physical and verbal aggression; the other scales of the Aggression Questionnaire measure anger and hostility, and those of the Aggression Inventory measure impulsiveness and avoidance of aggression. The factor structure of scales were assessed using confirmatory factor analysis. The interrelations of the subscales were calculated in both cases: anger was independently related to verbal and physical aggression and to hostility on the Aggression Questionnaire; impulsivity, and verbal and physical aggression were associated on the Aggression Inventory. Sex differences were largest on the two physical subscales, of lesser magnitude but still significantly different for the two verbal subscales, but absent for anger and hostility. This supports the hypothesis that sex differences in aggression are larger for more escalated forms of aggression. The physical and verbal subscales of the two questionnaires were each highly correlated with one another and the impulsive subscale of the Aggression Inventory highly correlated with the anger subscale of the Aggresion Questionnaire. Thus, two aggression questionnaires developed in the US not only produce similar associations between subscales and sex differences among a British undergraduate sample, but also show high correlations between their respective scales. © 1995 Wiley-Liss, Inc.     

Sex differences in genetic and environmental effects on aggression

The aim of the present study was to investigate the genetic and environmental factors influencing teacher and parental rated aggression in boys and girls, asking whether the magnitude of these effects is similar across rater and sex. The study is part of an ongoing nationwide twin‐family study of behavioral development and health habits carried out in Finland. The sample consisted of 1651 twin pairs (264 monozygotic male, 300 monozygotic female, 292 dizygotic male, 278 dizygotic female, and 517 dizygotic opposite‐sex twin pairs), representing subsets of five 11‐ to 12‐year‐old twin cohorts (b. 1983–1987). The data were collected using the teacher and parental rating forms of the Multidimensional Peer Nomination Inventory. Structural equation models of sex‐limitation assessed sex differences in genetic and environmental influences on aggression. The results suggested significant genetic, common environmental, and specific environmental effects on aggression in both boys and girls, but the best fitting model differed depending on the informant. For both ratings, boys showed lower levels of heritability and higher levels of common environment than girls. In addition, the teacher rating data also suggested the presence of either sex‐specific common environmental effects or sex‐specific genetic effects. Support is provided also for sibling contrast effects, either at the behavioral level or as a rater bias. Aggr. Behav. 29:55–68, 2003. © 2003 Wiley‐Liss, Inc.     

Psychopathic personality traits in relational aggression among young adults

Psychopathy is a robust predictor of overt physical aggression that may also be relevant to relational aggression (RA). This study was conducted to investigate the utility of psychopathic personality traits in the prediction of RA in a sample of 291 college students. Hierarchical multiple regression analyses indicated that both primary and secondary psychopathic traits explained additional variance in general/peer and romantic RA beyond physical aggressiveness. Consistent with previous research, no gender differences were found on either form of RA, challenging the popular stereotype of RA as a female behavior. Moreover, psychopathic traits were not differentially predictive of RA by gender or level of physical aggressiveness. Implications of these findings for research and clinical practice are discussed.     

Sex differences in processing aggression words using the Emotional Stroop task

There is a robust relationship between the salience of stimulus materials presented in the Emotional Stroop task and inhibition of response in clinical populations. Researchers have now found information‐processing biases in both forensic and non‐forensic samples presented with threatening or aggressive stimuli [Cohen et'al., 1998; Eckhardt and Cohen, 1997; Smith and Waterman, 2003; Van Honk et'al., 2001]. We sought to explore sex differences in processing words relating to acts of direct and indirect aggression using a group of undergraduates (50 males and 50 females). Participants also completed self‐report questionnaires (AQ and EXPAGG) to allow some consideration of the relationship between objective and subjective measures. We predicted that males would demonstrate delayed responses when presented with words relating to acts of direct aggression. We also predicted that high levels of physical aggression would be the best predictor of bias for direct aggression words, high levels of verbal aggression would be the best predictor of bias for indirect aggression words, physical aggression would predict bias in males, and verbal aggression would predict bias in females. Males demonstrated a perceptual bias for words relating to acts of direct aggression, taking significantly longer to correctly colour name direct aggression words. Females were slower to correctly colour name indirect aggression words, but not significantly so. Verbal aggression, as expected, predicted bias performance for indirect aggression words but anger rather than physical aggression was the best predictor of bias for direct aggression words. Gender was a predictor for bias with both sets of words. Contrary to our predictions, it was observed that a high level of physical aggression was the best predictor of bias in both males and females. These data provide further evidence to confirm the saliency of aggression words to aggressive individuals in non‐forensic populations. Aggress. Behav. 00:00–00, 2005. © 2005 Wiley‐Liss, Inc.     

Sex,race, and experiences of aggression

Most previous research on sex differences in experienced aggression has confounded the sex of the aggressor and of the target by considering married or dating couples. In the present study, black and white male and female college students were asked about specific acts of aggression which they had received from or directed toward a male or female. As predicted, males were likely to have both received and exhibited more forms of aggressive behavior, although females were somewhat more likely to have been honked at, to have been forced by a male to have sex, and to have slapped someone. Few racial differences were found, but it appeared that blacks might have been relatively more likely to exhibit physical aggression and whites to exhibit nonphysical aggression. Some differences were found in specific behaviors directed toward and received from males and females, but in general subjects said that they received more aggressive behaviors than they directed toward others. © 1992 Wiley-Liss, Inc.     

Cooperative social coordination and aggression: Sex and strain differences in the effects of housing on gonadectomized rats with hormone replacement

Laboratory rats were used to investigate sex and strain differences in the effects of aggression on a cooperative behavior in which pairs learn to coordinate shuttling in a rectangular chamber. The level of aggression was manipulated by comparing males and females of the aggressive S3 strain and a less aggressive Sprague-Dawley-derived strain and by housing same-sex partners either together or individually (eight groups, n = 7 pairs per group). Hormone levels were stabilized by gonadectomy and daily injections of the appropriate sex hormone. The only serious coordination deficits were in individually housed males, associated with violent fighting and an extreme dominance/subordinance relationship that was not observed in females. All other groups readily learned and performed the coordination, with evidence that low and moderate levels of aggression could facilitate coordination by evoking species-typical behaviors that increased proximity, synchrony, and differentiation within pairs. The discussion focused on models of affiliative behavior in the study of aggression and the compatibility between moderate levels of aggression and cooperation.     

Victim and peer group responses to different forms of aggression among primary school children

Both behaviourist and social learning theory emphasise the importance of the consequences of a behaviour on its subsequent frequency of occurrence [e.g., Bandura, 1973, 1977; Skinner, 1953]. Despite this, very little is known about the types of consequences children receive when they aggress towards other children. The present study employed a wireless microphone and hidden camera to record victim and peer responses to primary school children's physical, verbal, indirect, and relational forms of aggression. The results showed that the most frequent consequences of aggression were victim retaliation or withdrawal, and peer support. In addition, the results showed limited support for the suggestion that sex differences in the use of different types of aggression arise due to differential reinforcement from victims and/or peers. The implications of the results for the development of interventions aimed at reducing aggression are considered along with alternative explanations for sex differences in aggression. Aggr. Behav. 31:00–00, 2005. © 2005 Wiley‐Liss, Inc.     

Adolescent perceptions of indirect forms of relational aggression: sex of perpetrator effects

Different types of aggressive behavior (both physical and relational) by boys and girls have been shown to be perceived differently by observers. However, most research has focused on adult perceptions of very young children, with little research examining other ages. The aim of this study is to establish any sex differences in adolescent perceptions of indirect forms of relational aggression enacted by boys and girls. One hundred and sixty adolescents were shown one of the two videos involving relational aggression and completed a questionnaire that assessed their perceptions of the aggression. The videos were identical except for the sex of the aggressor and the victim; one condition portrayed boy-to-boy aggression, the other showed girl-to-girl aggression. Results indicated that participants viewed boy-to-boy relational aggression as more justified. This study revealed that stereotypes about aggressive boys are perpetuated even when the aggression is a type that is not commonly associated with boys.