Relationship between mousekilling and conspecific aggression in the male rat

In order to investigate the relationships between mousekilling and conspecific aggression, behavioral variables of killer and nonkiller rats were compared in a “resident-intruder” paradigm, in resident as well as in intruder animals. The occurrence of offensive items (offensive sideways, attack) was significantly higher in killer rats when they were residents; their corresponding opponents displayed more defensive behaviors. No significant difference in aggressive behaviors was noted when the comparison was done in the intruders. These results and those of previous studies suggest that there is a correlation between mousekilling and intraspecific offensive behaviors. Some similarities in the situations where both behaviors are elicited–eg, introduction of an unfamiliar intruder into a familiar environment–may contribute to the existence of such a correlation and the possibility of common mechanisms underlying both behaviors is discussed.     

Olfactory stimuli and intermale aggression in androgen-treated castrated sheep

The ability of olfactory stimuli to elicit aggression in male sheep was assessed in testosterone-treated castrates. Ablation of the olfactory bulbs (Exp. 1) did not reduce the capacity of sheep to participate in aggressive behaviour after testosterone treatment. Topical application of urine from castrates treated with propionated testosterone, 5α-dihydrotestosterone, 17β-oestradiol, or an oil vehicle to the fleeces of untreated castrates (Exp. 2) did not result in different levels of aggressive responsiveness in testosterone-treated castrates.     

The septum: neural systems involved in eating, drinking, irritability, nuricide, copulation, and activity in rats.

Eating, drinking, irritability, muricide, and copulation were measured in 45 male rats before and after one of three coronal knife cuts in the septal region or a control operation; in addition, activity was measured postoperatively. (a) Cuts posteroventral to the septum resulted in slight hypophagia, marked hyperdipsia, irritability, asexuality, and decrease in activity. (b) Cuts of the fornix resulted only in slight decrease in activity. (c) Cuts through the anterior septum resulted in irritability, slight hyposexuality, and slight decrease in activity. No significant correlations between the various behavioral effects were found. It was suggested that the neural pathways mediating eating, drinking, irritability, muricide, copulation, and activity are relatively distinct and that neural activity in the septal region probably does not influence behavior in any unitary fashion.     

Indicators of impulsive aggression: Present status of research on irritability and emotional susceptibility scales

Results of recent studies on Irritability and Emotional Susceptibility scales are presented. The developed scales have been proposed primarily for the research on individual differences concerning the manifestation of impulsive aggression. Principal-components analysis confirms the unifactorial structure of both scales and its stability with respect to groups of Ss of different language, nationality and cultural context. Content validity of both scales is clarified by their interrelationships with other measurements, and construct validity of both scales is clarified by a series of experimental studies.     

male self-control and sexual aggression

This study examines judgments of male self-control regarding sexual aggression in dating situations. A survey was conducted using vignettes that described situations where a hypothetical man attempts to have intercourse with his female date, she resists, and he considers various ways of overcoming her resistance. Survey respondents judged these vignettes. The goals of the study were to estimate the prevalence of beliefs about low male self-control, and to examine how contextual information affects these assessments. Contrary to expectations derived from the literature, the large majority of respondents attributed high levels of self-control to men across a wide range of scenarios. As expected, the man's alcohol intoxication reduced perceived control. Against expectations, consensual foreplay and prior sex did not affect ratings. Implications for social learning and rational choice theories of sexual aggression are discussed, with particular emphasis on Ajzen's (1988) theory of planned behavior.     

Fear and aggression in the rat

The effect of fear on two types of aggression in rats was investigated by adding a cat stimulus to a colony in which the dominant male was attacking an intruder (offensive aggression), or, to a tube test situation in which defensive biting was measured before and during tail shock. The cat completely abolished offense in the colony; when the cat was presented and removed before a strange rat was placed in the colony, attack on the intruder was also reduced. In contrast, defensive biting was unchanged or even slightly potentiated by the presence of the cat, demonstrating a separation of the effects of fear on offensive and defensive aggression.     

Predicting laboratory aggression against female and male targets: Implications for sexual aggression

This study assessed the ability of several variables to predict men's laboratory aggression against female and male victims. The predictors were chosen on the basis of their associations with sexual aggression against women in naturalistic settings. On the whole, these variables successfully predicted laboratory aggression against the female target but were not similarly related to aggression against the male. The data supported the view that specific factors uniquely contribute to aggression against women. It is suggested that, at least in part, such aggression needs to be examined within the larger context of sexist relations.     

Interpolating physical exercise between instigation to aggress and aggression: The role of irritability and emotional susceptibility

Two studies were conducted using the Buss aggression machine paradigm to investigate the mediational role of physical exercise with respect to subsequent aggression in relation to the presence or absence of previous instigation. The irritability level of subjects was taken into account in the first study, and the subject' emotional susceptibility level in the second study. In both studies sex differences were also considered so that each study resulted in a 2 × 2 × 2 × 2 design with ten subjects in each cell. As far as irritability is concerned, experimental subjects (pedaling on a bicycle ergonometer) delivered higher shocks than controls (who just waited out the 10 min the experimental subjects were pedaling), independent of irritability level or of the presence or absence of previous instigation. When emotional susceptibility was taken into consideration, physical exercise associated with high level of emotional susceptibility and previous instigation resulted in increased intensity of the shocks subsequently delivered. These findings are discussed in terms of the importance of stable personality characteristics that may differentially mediate aggression.     

Individual differences conducive to aggression and violence: trajectories and correlates of irritability and hostile rumination through adolescence

This study examined the developmental trends of Irritability and Hostile Rumination at different times over the course of adolescence in a sample of 500 youth. Participants were 12 years old at the time of the first assessment and 20 years old at the last assessment time. Three objectives were pursued: (a) investigation of the stability and change of both Irritability and Hostile Rumination; (b) identification of developmental trajectories of Irritability and Hostile Rumination; and (c) determination of whether different trajectories of Irritability and Rumination were significantly related to physical and verbal aggression and violent conduct at age 20. Results showed that Irritability and Hostile Rumination were highly correlated and stable over time. Four developmental trajectories were identified for both dimensions. Whereas most of the participants demonstrated stable mean levels of Irritability, half of the youth either increased or decreased in their level of Hostile Rumination over time. In addition, high Irritability trajectories were associated with high physical and verbal aggression while high Hostile Rumination trajectories were associated with high levels of violent behavior.     

Relational aggression and victimization in gay male relationships: the role of internalized homophobia

This article presents two studies that are the first to examine relational aggression and relational victimization in gay male peer relationships. A qualitative pilot study provides a strong rationale for a subsequent empirical investigation of 100 young adult, self-identified gay males. Results of both studies demonstrate that relational aggression and relational victimization are common experiences in gay male relationships. They also reveal forms of relational aggression and victimization that appear to be unique to gay males (e.g., outing). Results of the empirical study found significant relations between engaging in relational aggression against gay males and experiencing relational victimization and between experiencing relational victimization and internalized homophobia. However, there was no significant correlation between internalized homophobia and engaging in relational aggression. A multiple regression analysis found that experiencing relational victimization was correlated more strongly with the combination of engaging in relational aggression and internalized homophobia together than with relational aggression alone. Results are discussed within the framework of Allport's "traits due to victimization" theory and Meyer's theory of "minority stress." Implications for the prevention of relational aggression/victimization in gay male relationships are offered.