Research on cognitive processes has primarily focused on cognitive control and inhibitory processes to the detriment of other psychological processes, such as defense mechanisms (DMs), which can be used to modify aggressive impulses as well as self/other images during interpersonal conflicts. First, we conducted an in-depth theoretical analysis of three socio-cognitive models and three psychodynamic models and compared main propositions regarding the source of aggression and processes that influence its enactment. Second, 32 participants completed the Hostile Expectancy Violation Paradigm (HEVP) in which scenarios describe a hostile vs. non-hostile social context followed by a character's ambiguous aversive behavior. The N400 effect to critical words that violate expected hostile vs. non-hostile intent of the behavior was analyzed. Prepotent response inhibition was measured using a Stop Signal task (SST) and DMs were assessed with the Defense Style Questionnaire (DSQ-60). Results showed that reactive aggression and HIA were not significantly correlated with response inhibition but were significantly positively and negatively correlated with image distorting defense style and adaptive defense style, respectively. The present article has highlighted the importance of integrating socio-cognitive and psychodynamic models to account for the full complexity underlying psychological processes that influence reactive aggressive behavior.

From a neuropsychological perspective, impulsive aggression and its treatment are usually conceptualized in most research as a closed executive functioning system, as though the behavior was the product of the person's cerebral functioning only. However, recent studies in social cognitive neuroscience have emphasized the influence of social factors on cognitive processes and cerebral functioning for the development and maintenance of impulsive aggression. This chapter will review studies that highlight the relevance of initiating a shift of paradigm from a one-person-cerebral functioning model to a social interactive-cerebral functioning model of impulsive aggression. First, the influences of an aversive environment on a child's cognitive processes and executive functioning will be discussed with the aim of explaining the development of impulsive aggressive behaviors in early childhood. Second, we will review studies that have shown how the link between social information processes and executive/inhibitory functioning serve to maintain behaviors. Finally, strengths and weaknesses of existing inhibitory control strategies will be discussed with the intention of proposing some novel ideas that incorporate a twoperson neuropsychological approach.

<b><i>Introduction:</i></b> Splitting, as a defense mechanism in Kernberg’s theory, plays a significant role in the development and maintenance of polarized and oscillating representations of self/other characteristics of borderline personality disorder (BPD). Although the notion of splitting can be considered from a structural and a functional point of view, almost all empirical studies to date have focused on the former elements to the detriment of related cognitive processes. <b><i>Methods:</i></b> To further investigate the cognitive processes related to splitting, 60 participants were administered the Splitting Index and indexes of resistance to proactive interference (PI) using the interpersonal recent negative task with words that reflect negative or positive interactions compared to neutral words. <b><i>Results:</i></b> The use of splitting was uniquely and significantly predicted by a higher capacity to resist PI and a lower capacity to consistently maintain this resistance when presented with negative words, above and beyond BPD traits, primitive defenses, and the presentation of neutral words. Results showed no evidence of a relationship between splitting and resistance to PI with positive words. <b><i>Conclusion:</i></b> Results appear compatible with Kernberg’s conceptualization of splitting as an active defense process that relates to an unstable capacity to inhibit negative representations of the object from entering working memory.

The aim of this study was to better understand the role of hostile attribution bias (HAB) in the relationship between cluster B personality traits and reactive aggression. Sixty-three French-speaking adults were asked to complete online questionnaires assessing their personality traits, hostile attribution bias, and aggressive behaviors. While brain activity was recorded, they were asked to read scenarios involving daily life interactions and to imagine why the characters (whose intentions were ambiguous) behaved in a provocative manner toward them. Following each scenario, we analyzed the N400 component of the event-related brain potential associated with the presentation of unexpected hostile or nonhostile intentions after each scenario. Results showed a stronger N400 amplitude during the presentation of unexpected nonhostile intentions (hostile expectancy violations) in the centro-parietal regions. There was no mediating effect of hostile or nonhostile expectancy violation in the relationship between cluster B personality characteristics and reactive aggression. Further studies are needed to better understand the psychological processes underlying aggressive behaviors in cluster B personality disorders.