The facial width-to-height ratio (FWHR) is the width of the face divided by the height of the upper face. There is mixed evidence for the hypothesis that the FWHR is a cue of threat and dominance in the human face. We conducted a systematic review and meta-analyses of all peer-reviewed studies (and 2 unpublished studies) to estimate the magnitude of the sex difference in the FWHR, and the magnitude of the relationship between the FWHR and threatening and dominant behaviours and perceptions. Studies were eligible for inclusion if the authors reported an analysis involving the FWHR. Our analyses revealed that the FWHR was larger in men than in women ( = .11, n = 10,853), cued judgements of masculinity in men ( = .35, n of faces = 487; n of observers = 339), and was related to body mass index ( = .31, n = 2,506). Further, the FWHR predicted both threat behaviour in men ( = .16, n = 4,603) and dominance behaviour in both sexes ( = .12, n = 948) across a variety of indices. Individuals with larger FWHRs were judged by observers as more threatening ( = .46, n of faces = 1,691; n of observers = 2,076) and more dominant ( = .20, n of faces = 603; n of observers = 236) than those with smaller FWHRs. Individuals with larger FWHRs were also judged as less attractive ( = -.26, n of faces = 721; n of observers = 335), especially when women made the judgements. These findings provide some support for the hypothesis that the FWHR is part of an evolved cueing system of intra-sexual threat and dominance in men. A limitation of the meta-analyses on perceptions of threat and dominance were the low number of stimuli involving female and older adult faces.

Interpersonal provocation is a common and robust antecedent to aggression. Four studies identified angry rumination and reduced self-control as mechanisms underlying the provocation-aggression relationship. Following provocation, participants demonstrated decreased self-control on an unpleasant task relative to a control condition (Study 1). When provoked, rumination reduced self-control and increased aggression. This effect was mediated by reduced self-control capacity (Study 2). State rumination following provocation, but not anger per se, mediated the effect of trait rumination on aggression (Study 3). Bolstering self-regulatory resources by consuming a glucose beverage improved performance on a measure of inhibitory control following rumination (Study 4). These findings suggest that rumination following an anger-inducing provocation reduces self-control and increases aggression. Bolstering self-regulatory resources may reduce this adverse effect.

Previous measures of aggressive personality have focused on direct aggression (i.e., retaliation toward the provoking agent). An original self-report measure of trait displaced aggression is presented. Exploratory and confirmatory factor analyses provided support for a 3-factor conceptualization of the construct. These analyses identified an affective dimension (angry rumination), a cognitive dimension (revenge planning), and a behavioral dimension (general tendency to engage in displaced aggression). The trait measure demonstrated good internal consistency and test-retest reliability as well as convergent and discriminant construct validity. Unlike other related personality measures, trait displaced aggression significantly predicted indirect indicators of real-world displaced aggression (i.e., self-reported domestic abuse and road rage) as well as laboratory displaced aggression in 2 experiments.

We provide a new framework for understanding 1 aspect of aggressive conflict between groups, which we refer to as vicarious retribution. Vicarious retribution occurs when a member of a group commits an act of aggression toward the members of an outgroup for an assault or provocation that had no personal consequences for him or her but which did harm a fellow ingroup member. Furthermore, retribution is often directed at outgroup members who, themselves, were not the direct causal agents in the original attack against the person's ingroup. Thus, retribution is vicarious in that neither the agent of retaliation nor the target of retribution were directly involved in the original event that precipitated the intergroup conflict. We describe how ingroup identification, outgroup entitativity, and other variables, such as group power, influence vicarious retribution. We conclude by considering a variety of conflict reduction strategies in light of this new theoretical framework.

Psychological science has largely neglected the role of self-control in studying aggression. Fortunately, the past half decade has witnessed a surge of research on this long-neglected topic, including two self-control-informed integrative theories of aggression. Robust experimental evidence demonstrates that self-control failures frequently predict aggression and, conversely, that bolstering self-control decreases aggression. Research on rumination also suggests that maladaptive anger regulation decreases self-control and, consequently, increases aggression. Advances from social-affective and cognitive neuroscience suggest that the neural mechanisms involved in emotion regulation and cognitive control mediate the relationship between deficient self-control and aggression.