Aggressive behavior and physiological arousal as a function of provocation and the tendency to inhibit aggression

Those who (enjoy to) hurt: The influence of dark personality traits on animal- and human directed sadistic pleasure

BACKGROUND AND OBJECTIVES

Sadistic pleasure - gratuitous enjoyment from inflicting pain on others - has devastating interpersonal and societal consequences. The current knowledge on non-sexual, everyday sadism - a trait that resides within the general population - is scarce. The present study therefore focussed on personality correlates of sadistic pleasure. It investigated the relationship between the Dark Triad traits, and both dispositional and state-level sadistic pleasure.

METHODS

N = 120 participants filled out questionnaires to assess their level of Dark Triad traits, psychopathy subfactors, and dispositional sadism. Then, participants engaged in an animal-directed task in which they were led to believe that they were killing bugs; and in a human-directed task where they could ostensibly noise blasts another participant. The two behavioral tasks were administered within-subjects, in randomized order. Sadistic pleasure was captured by increases in reported pleasure from pre-to post-task.

RESULTS

All Dark Triad traits related to increased dispositional sadism, with psychopathy showing the strongest link. The coldheartedness psychopathy subscale showed a unique combination with both self-reported sadism and increased pleasure following bug grinding.

LIMITATIONS

Predominantly female and student sample, limiting generalizability of findings.

CONCLUSIONS

Out of all Dark Triad components, psychopathy showed the strongest link with gaining pleasure from hurting others. The results underscore the differential predictive value of psychopathy's subcomponents for sadistic pleasure. Coldheartedness can be considered especially disturbing because of its unique relationship to deriving joy from irreversible harm-infliction (i.e. killing bugs). Our findings further establish psychopathy - and especially its coldheartedness component - as the most adverse Dark Triad trait.

Chemical cousins with contrasting behavioural profiles: MDMA users and methamphetamine users differ in social-cognitive functions and aggression

Methamphetamine (METH, "Crystal Meth") and 3,4-methylenedioxymethamphetamine (MDMA, "Ecstasy") share structural-chemical similarities but have distinct psychotropic profiles due to specific neurochemical actions. Previous research has suggested that their impact on social cognitive functions and social behaviour may differ significantly, however, direct comparisons of METH and MDMA users regarding social cognition and interaction are lacking. Performances in cognitive and emotional empathy (Multifaceted Empathy Test) and emotion sensitivity (Face Morphing Task), as well as aggressive social behaviour (Competitive Reaction Time Task) were assessed in samples of n = 40 chronic METH users, n = 39 chronic MDMA users and n = 86 stimulant-naïve controls (total N = 165). Self-reports and hair samples were used to obtain subjective and objective estimates of substance use patterns. METH users displayed diminished cognitive and emotional empathy towards positive stimuli, elevated punitive social behaviour regardless of provocation, and self-reported heightened trait anger relative to controls. MDMA users diverged from the control group only by exhibiting a distinct rise in punitive behaviour when faced with provocation. Correlation analyses indicated that both higher hair concentrations of MDMA and METH may be associated with reduced cognitive empathy. Moreover, greater lifetime MDMA use correlated with increased punitive behaviour among MDMA users. Our findings confirm elevated aggression and empathy deficits in chronic METH users, while chronic MDMA users only displayed more impulsive aggression. Dose-response correlations indicate that some of these deficits might be a consequence of use. Specifically, the dopaminergic mechanism of METH might be responsible for social-cognitive deficits.

Comparing behavioral measures of aggression in the laboratory: Taylor Aggression Paradigm versus Point-Subtraction Aggression Paradigm

Aggression refers to a wide range of behaviors with lasting individual and societal consequences. Recurrent, unplanned aggressive behavior is the core diagnostic criterion for intermittent explosive disorder (IED). In this study, we compared two behavioral measures of aggression in the laboratory: the Taylor Aggression Paradigm (TAP) and the Point-Subtraction Aggression Paradigm (PSAP). This sample (n = 528) included community participants who met DSM-5 criteria for IED (n = 156), met DSM-5 criteria for a nonaggressive psychiatric disorder (n = 205), or did not meet DSM-5 criteria for any psychiatric disorder (n = 167). All participants completed the TAP, a single-session PSAP, and relevant self-report measures. MANOVA analyses demonstrated differences between IED participants and nonaggressive participants; however, these group differences were no longer significant for the PSAP after including demographic variables. Correlation analyses found that the TAP and PSAP were positively related to one another and the composite variables associated with aggressive behavior (i.e., history of aggression, impulsivity, and propensity to experience anger) and; dependent correlations revealed that past aggression and trait anger were more strongly related to the TAP. Differences in TAP and PSAP outcomes may be partially attributed to operationalizations of aggression and methods of aggression and provocation. Further, as aggressive and nonaggressive participants differed on the PSAP somewhat mirroring the TAP, our results add to growing evidence of the validity of a single-session PSAP; further research is needed to fully establish single-session PSAP as a laboratory aggression task compared to the multi-session PSAP.

The link between anger and reactive aggression: Insights into anger rumination

This study examined the mediating role of anger rumination in the relationship between anger and reactive aggression and the potential of adaptive anger rumination in reducing reactive aggression. Study 1, a two-wave longitudinal survey of 177 Chinese adolescents, showed that anger rumination mediated the relationship between anger and reactive aggression. Study 2, an experimental study with 160 university students, showed that the self-distanced group had lower aggression than the self-immersed group, and anger rumination mediated the impact of anger on reactive aggression in only the self-immersed group. These findings clarify the role of anger rumination concerning the relationship between anger and reactive-aggression and highlight the importance of self-distanced anger rumination in preventing reactive aggression among adolescents and young adults.

Common Mechanisms Underlying the Effect of Angry Rumination on Reactive and Proactive Aggression: A Moderated Mediation Model

The different influencing factors and mechanisms of the two basic kinds of aggression (i.e., reactive and proactive aggression) are salient. However, they also have common influencing factors and mechanisms, which are ignored to some extent. In addition, discovering the common mechanisms is conducive to further revealing the nature and law of aggression. To address these issues, this study tested a relational model incorporating angry rumination, moral disengagement, harm aversion, reactive aggression, and proactive aggression from the perspective of aggressive motivation. A total of 1,186 undergraduate students from eight universities were recruited. The results showed that angry rumination was significantly associated with reactive and proactive aggression. Importantly, moral disengagement acted as a common mediator, and harm aversion acted as a common moderator in the effect of angry rumination on reactive and proactive aggression. Specifically, the enhancement effects of low levels of harm aversion on these relationships are due to that it could promote the effects of angry rumination on the common mediator of moral disengagement. An aggressive motivation perspective was developed to comprehensively explain the common mediating and moderating effects. The present study contributes to a greater understanding of the mechanisms of reactive and proactive aggression and how aggressive motivations shape the model of aggressive behavior. These findings support and extend current aggression theories, especially aggression motivation theories. This study could provide insights for targeted aggression prevention interventions.

A quasi-experimental study in sibling dyads: differential provocation-aggression patterns in the interactive taylor aggression paradigm

Introduction

The Taylor Aggression Paradigm (TAP) is a well-established tool for assessing provocation-induced reactive aggression. We introduce an interactive version, the iTAP, with real-time opponents across 60 trials, including five simulated provocation trials in the middle. In this quasi-experimental study, we evaluate the effectiveness of the paradigm to investigate reactive aggression in interacting participants. The design allows us to employ the TAP in settings of high familiarity dyads, addressing an existing gap.

Method

Twenty-eight healthy same-sex adult sibling pairs (N = 56) competed against each other in the iTAP, exemplifying high familiarity through their social and emotional co-development, and mutual knowledge. Additionally, we explore naturally arising aggression types in terms of sibling pairs' reciprocal aggression trajectories across trials. Lastly, we investigate situational and personal variables influencing reactive aggression on the iTAP within high familiarity dyads.

Results

In line with non-interactive TAP versions, siblings employed a global "tit-for-tat" strategy in response to heightened provocation: Aggression increased during manipulated trials of increasing provocation, persisted during real interaction and declined in the final block, suggesting sibling co-regulation which was underscored by the convergence in within-pair aggression level. We found no gender differences in these dynamics but a trend for higher initial aggression levels within brother pairs and higher responsiveness to increased provocation in sister pairs. Overall aggression levels were related to situational variables including trial outcome (lost, won, and tie), Further, siblings' state anger correlated positively with aggression scores on the iTAP. Aggression was not reliably related to personal variables predicting aggression. We identified subgroups of sibling pairs with distinct provocation-aggression patterns related to differences in reported behavioral motivations and emotional states. The results highlight situational over personal variables in determining aggressive behavior on the task in this sample of healthy adults. While no direct link between sibling relationship quality and aggression was found, the overall behavior was likely influenced by the familiarity between siblings and the specific context of their relationship.

Conclusion

The iTAP demonstrates promise as a tool for studying reciprocal aggressive behavior. The emergence of different interaction patterns underscores the ecological validity introduced by the interactive context, which complements the standard versions of the TAP.

Characterizing the role of impulsivity in costly, reactive aggression using a novel paradigm

A lack of self-control has long been theorized to predict an individual's likelihood to engage in antisocial behaviors. However, existing definitions of self-control encompass multiple psychological constructs and lab-based measures of aggression have not allowed for the examination of aggression upon provocation where self-control is needed most. We introduce two versions of a novel paradigm, the Retaliate or Carry-on: Reactive AGgression Experiment (RC-RAGE) to fill this methodological gap. Using large online samples of US adults (N = 354 and N = 366), we evaluate to what extent dispositional impulsivity, self-control, aggression, and state anger contribute to aggression upon provocation when there is a financial cost involved. Results showed that costly retaliation on this task was related to trait aggression and being in an angry emotional state, but not related to social desirability. Importantly, we show that the tendency to act impulsively is a better predictor of costly retaliation than other forms of self-control, such as the ability to delay gratification, resist temptation, or plan ahead. As a browser-based task, the RC-RAGE provides a tool for the future investigation of reactive aggression in a variety of experimental settings.

Unraveling the Complex Interactions of Psychological Factors Contributing to Cyber Reactive Aggression Among College Students: Network and Mediation Analyses

Cyber reactive aggression (CRA) among college students is a prevalent and harmful phenomenon. Psychological characteristics, such as trait anger (TA), hostile attribution bias (HAB), and revenge motivation (RM), are known to contribute to reactive aggression. However, the interactions between these factors in the context of cyberspace and their contribution to CRA among college students have not been extensively studied. This cross-sectional study aimed to identify the associations among psychological characteristics, demographic factors, and CRA among Chinese college students through Mixed Graphical Model (MGM) network and mediation effect analyses. A total of 926 participants completed questionnaires assessing TA, HAB, RM, and CRA. The study found both direct and indirect relationships between TA and CRA, with HAB and RM serving as mediating factors. Comparisons indicated that HAB had a more significant impact on the three indirect effects than RM. Furthermore, gender was found to be associated with TA and CRA, while the left-behind experience strongly influenced HAB but had no association with other variables. This study highlights the importance of considering psychological characteristics and demographic factors in understanding CRA among college students, suggesting that effective psychological interventions, such as anger management, and promoting positive attribution training, may help reduce CRA among college students and inform the development of targeted interventions to reduce cyber aggression.

Sadism in the context of intergroup aggression

People more readily harm members of outgroups than ingroups, often enjoying the inflicted agony. Yet it remains unclear how these malevolent tendencies towards outgroups relate to sadism. Sadists often harm others, driven by a desire to feel pleasure from their suffering. In attempt to bridge these two lines of research, this work examined relationships between sadism and aggression against ingroup and outgroup members in three studies (total N = 755) that focused on two groups with a history of conflict (i.e., the United Kingdom and the Republic of Ireland). Across all studies, British participants' sadistic tendencies were just as strongly linked to their aggression against ingroup members (i.e., British partners) as to their aggression against outgroup members (i.e., Irish partners). Despite this lack of a preference for greater outgroup aggression, they tended to enjoy outgroup aggression more than ingroup aggression, especially at its extreme levels. These findings extend works linking sadism to aggression into the domain of intergroup relations and bind together research on sadism and intergroup schadenfreude.

Alcohol Use, Discrimination, and Psychological Partner Abuse Among LGBQ+ College Students: Results From a Daily Diary Study

Alcohol use correlates with psychological partner abuse (PA) perpetration among lesbian, gay, bisexual, queer, and other nonheterosexual (LGBQ+) young adults. However, less is known about the proximal association between alcohol use and psychological PA within this population, which would provide valuable information for intervention development. Informed by minority stress and alcohol-related PA theories, we evaluated whether (a) psychological PA perpetration odds increased as the number of drinks consumed prior to psychological PA on a given day increased, (b) psychological PA perpetration odds were greater following heavy episodic drinking (HED) relative to non-HED, and (c) experiencing LGBQ+-specific discrimination (i.e., heterosexist harassment, incivility, and hostility) strengthened the association between daily alcohol use (number of drinks, HED) and subsequent psychological PA perpetration. LGBQ+ college students (N = 41; 75.6% women, 22.0% men, and 2.4% transgender/non-binary) completed a baseline survey of past-year discrimination before completing daily reports of their alcohol use and psychological PA for 60 consecutive days. Multilevel modeling revealed that drinking more than one usually does on a given day is positively associated with subsequent psychological PA odds (OR = 1.31, p < .001). Psychological PA was more likely following HED relative to non-HED (OR = 3.23, p < .001). Unexpectedly, experiencing discrimination was negatively associated with psychological PA odds across models (OR = .26 p = .01). No alcohol × discrimination interactions emerged. Results support alcohol use as a proximal risk factor for psychological PA among LGBQ+ college students and underscore the need for more nuanced examination of discrimination and other contextual variables in alcohol-related PA.

Representational similarity analysis of self- versus other-processing: Effect of trait aggressiveness

In this study, using the self/other adjective judgment task, we aimed to explore how people perceive themselves in comparison to various other people, including friends, strangers, and those they dislike. Next, using representational similarity analysis, we sought to elucidate how these perceptual similarities and differences are represented in brain activity and how aggressiveness is related to these representations. Behavioral ratings show that, on average, people tend to consider themselves more like their friends than neutral strangers, and least like people they dislike. This pattern of similarity is positively correlated with neural representation in social and cognitive circuits of the brain and negatively correlated with neural representation in emotional centers that may represent emotional arousal associated with various social objects. Aggressiveness seems to predispose a person to a pattern of behavior that is the opposite of the average pattern, that is, a tendency to think of oneself as less like one's friends and more like one's enemies. This corresponds to an increase in the similarity of the behavioral representation with the representation in the emotional centers and a decrease in its similarity with the representation in the social and cognitive centers. This can be seen as evidence that in individuals prone to aggression, behavior in the social environment may depend to a greater extent on the representation of social objects in the emotional rather than social and cognitive brain circuits.

Nonverbal behavioral patterns predict social rejection elicited aggression

Aggression elicited by social rejection is costly, prevalent, and often lethal. Attempts to predict rejection-elicited aggression using trait-based data have had little success. This may be because in-the-moment aggression is a complex process influenced by current states of attention, arousal, and affect which are poorly predicted by trait-level characteristics. In a study of young adults (N = 89; 18-25 years), machine learning tested the extent to which nonverbal behavioral indices of attention (eye gaze), arousal (pupillary reactivity), and affect (facial expressions) during a novel social interaction paradigm predicted subsequent aggression towards rejecting and accepting peers. Eye gaze and pupillary reactivity predicted aggressive behavior; predictions were more successful than measures of trait-based aggression and harsh parenting. These preliminary results suggest that nonverbal behavior may elucidate underlying mechanisms of in-the-moment aggression.

Systematic Review of Gaming and Neuropsychological Assessment of Social Cognition

Playing video games is associated with cognitive changes and possibly psychosocial difficulties. Problematic gaming occurs upon the loss of control over videogame playing; gaming disorder is considered a behavioral addiction in the 11th version of the International Classification of Diseases. Models used to understand behavioral addictions include cognition as an essential factor in the development, maintenance, and relapse of addiction. Nevertheless, some aspects of cognition, such as social cognition, remain underexplored, despite evidence of alterations in cognitive and social function among patients with problematic gaming. This review aimed to describe the current understanding of social cognition in individuals exposed to videogames. We included all studies assessing social cognition in participants of any age with a wide range of exposure to video games (from simple use of video games (such as at least two exposures) to problematic gaming, defined according to the included study). This wide range of exposure allowed us to explore the whole process from repeated exposure to addiction. We included only studies that used neuropsychological tasks to assess social cognition. Patient-reported outcomes that could be biased by subjective self-report data were not included. The search was conducted from inception to January 2022 in three databases (PubMed, PsycINFO, and Web of Science). The systematic search identified 39 studies that assessed facial emotion processing, empathy, theory of mind, social decision-making, aggressive behavior, and moral competence. In general, results have been mixed, and a number of questions remain unanswered. Nevertheless, several studies showed cerebral changes when processing facial emotion that were linked with problematic gaming, while no link was obtained between nonproblematic gaming and empathy alterations. The influences of cooperation patterns, theory of mind, moral competence, and gaming frequency were highlighted. Finally, there was substantial heterogeneity in the population assessed and the methods used.

Association Between Aggression and Differential Functional Activity of Neural Regions Implicated in Retaliation

OBJECTIVE

The goal of the current study was to determine the extent to which atypical neural responsiveness during retaliation is associated with observed aggression in youth in residential care.

METHOD

This functional magnetic resonance imaging study involved 83 adolescents (56 male and 27 female; mean age, 16.18 years) in residential care performing a retaliation task. Of the 83 adolescents, 42 displayed aggressive behavior within the first 3 months of residential care, whereas 41 did not. During the retaliation task, participants were offered either fair or unfair divisions of $20 pots (allocation phase) and could either accept the offer or reject it, and, by spending $1, $2, or $3, punish the partner (retaliation phase).

RESULTS

The study's main findings were that aggressive adolescent showed the following: reduced down-regulation of activity within regions involved in representing the expected value of choice options (left ventromedial prefrontal cortex and left posterior cingulate cortex) as a function of offer unfairness and retaliation level; and reduced recruitment of regions implicated in response control (right inferior frontal gyrus and bilateral anterior insular cortex) and associated fronto-parietal regions as a function of retaliation level. The aggressive adolescents were also significantly more likely to have been aggressive prior to residential care and showed a strong trend for increased retaliation on the task.

CONCLUSION

We suggest that individuals with a greater propensity for aggression show reduced representation of the negative consequences of retaliation and associated reduced recruitment of regions potentially involved in over-ruling these negative consequences to engage in retaliation.

DIVERSITY & INCLUSION STATEMENT

We worked to ensure sex and gender balance in the recruitment of human participants. We worked to ensure that the study questionnaires were prepared in an inclusive way. We worked to ensure race, ethnic, and/or other types of diversity in the recruitment of human participants. We worked to ensure sex balance in the selection of non-human subjects. We actively worked to promote sex and gender balance in our author group. The author list of this paper includes contributors from the location and/or community where the research was conducted who participated in the data collection, design, analysis, and/or interpretation of the work. While citing references scientifically relevant for this work, we also actively worked to promote inclusion of historically underrepresented racial and/or ethnic groups in science in our reference list. While citing references scientifically relevant for this work, we also actively worked to promote sex and gender balance in our reference list. We actively worked to promote inclusion of historically underrepresented racial and/or ethnic groups in science in our author group.

Laboratory assessment of aggression: The Taylor Aggression Paradigm in adults with and without a disorder of impulsive aggression

INTRODUCTION

The modified Taylor Aggression Paradigm (TAP) has been used to study impulsive aggression in experimental designs and has been relatively successful in addressing critiques of aggression paradigms; however, little has been done to examine the potential of using the TAP as a direct measure of aggression. This study aimed to explore the psychometric properties of the TAP behavioral indexes as measures of aggression.

METHODS

A community sample of 962 adults were divided into three groups based on diagnostic assessments: Intermittent Explosive Disorder; Non-Aggressive Psychiatric Disorder; or healthy controls. Participants then completed the TAP and self-report measures to assess construct validity. A subset of 47 participants completed a second TAP within one year to assess reliability. TAP indexes were based on number of "extreme" shocks selected (high shock index), average shock levels selected (mean shock index), and shocks levels selected without provocation (unprovoked aggression).

RESULTS

Overall, TAP indexes were consistent and reliable. IED participants had the highest high shock and mean shock indexes of all groups (X2 = 49.93, p < 0.001). High shock index was related to trait aggression (β = 0.184, p < 0.001) after including covariates; mean shock index had a trending association with trait anger (β = 0.102, p = 0.059).

CONCLUSION

TAP behavioral indexes demonstrated promising psychometrics as a measure of aggression. High shock index appears to be more strongly associated with aggressive behavior; mean shock index may better measure general hostile responding. Future research might include comparisons specifically with impulse control disorders.

Effect of transcranial direct current stimulation over the left dorsolateral prefrontal cortex on the aggressive behavior in methamphetamine addicts

Aggressive behavior of drug addicts threatens human security and social stability, and Methamphetamine (MA) addicts show especially aggressive behavior. Researches showed that the decreased activity of dorsolateral prefrontal cortex (DLPFC) is closely related to violence and aggression, and continuous transcranial direct current stimulation (tDCS) on DLPFC can increase the activity of this position. So, the purpose of this study was to investigate the effect of tDCS on DLPFC for the aggressive behavior of MA addicts. Ninety MA addicts were recruited and randomly divided into anodal tDCS group, cathode tDCS group and sham tDCS group (current intensity was set as 2 mA, 2 mA and 0 mA, respectively). The tDCS intervention was conducted twice a day for five consecutive days. Taylor Aggression Paradigm (TAP) was used to measure the proactive aggressiveness and reactive aggressiveness of MA addicts at different time points (Pretest, Day 1, and Day 5). At the same time, we also recruited 30 healthy adult males as healthy controls, and measured their aggressiveness through TAP for comparative analysis. The results showed that the aggressiveness of MA addicts was significantly higher than that of healthy controls. The aggressiveness of MA addicts was effectively reduced by the anode intervention of tDCS on the left DLPFC, especially when they were subjected to high-intensity provocation, the 2-way interaction between time and tDCS group was statistically significant (F_4,164 = 2.939, P = 0.022, η_p² = 0.067). This study can provide a reference for how to correct the aggressive behavior of MA addicts.

Computerized cognitive and social cognition training in schizophrenia for impulsive aggression

BACKGROUND

Schizophrenia is associated with an elevated risk for impulsive aggression for which there are few psychosocial treatment options. Neurocognitive and social cognitive deficits have been associated with aggression with social cognitive deficits seemingly a more proximal contributor. The current study examined the effects of combining cognitive and social cognition treatment on impulsive aggression among inpatients with chronic schizophrenia and schizoaffective disorder and a history of aggression compared to cognitive remediation treatment alone.

METHODS

The two-center study randomized 130 participants to receive 36 sessions of either a combination of cognitive remediation and social cognition treatment or cognitive remediation plus a computer-based control. Participants had at least one aggressive incident within the past year or a Life History of Aggression (LHA) score of 5 or more. Participants completed measures of neurocognition, social cognition, symptom severity, and aggression at baseline and endpoint.

RESULTS

Study participants were mostly male (84.5 %), had a mean age 34.9 years, and 11.5 years of education. Both Cognitive Remediation Training (CRT) plus Social Cognition Training (SCT) and CRT plus control groups were associated with significant reductions in aggression measures with no group differences except on a block of the Taylor Aggression Paradigm (TAP), a behavioral task of aggression which favored the CRT plus SCT group. Both groups showed significant improvements in neurocognition and social cognition measures with CRT plus SCT being associated with greater improvements.

CONCLUSION

CRT proved to be an effective non-pharmacological treatment in reducing impulsive aggression in schizophrenia inpatient participants with a history of aggressive episodes. The addition of social cognitive training did not enhance this anti-aggression treatment effect but did augment the CRT effect on cognitive functions, on emotion recognition and on mentalizing capacity of our participants.

Non-Invasive Brain Stimulation for the Modulation of Aggressive Behavior-A Systematic Review of Randomized Sham-Controlled Studies

INTRO

Aggressive behavior represents a significant public health issue, with relevant social, political, and security implications. Non-invasive brain stimulation (NIBS) techniques may modulate aggressive behavior through stimulation of the prefrontal cortex.

AIMS

To review research on the effectiveness of NIBS to alter aggression, discuss the main findings and potential limitations, consider the specifics of the techniques and protocols employed, and discuss clinical implications.

METHODS

A systematic review of the literature available in the PubMed database was carried out, and 17 randomized sham-controlled studies investigating the effectiveness of NIBS techniques on aggression were included. Exclusion criteria included reviews, meta-analyses, and articles not referring to the subject of interest or not addressing cognitive and emotional modulation aims.

CONCLUSIONS

The reviewed data provide promising evidence for the beneficial effects of tDCS, conventional rTMS, and cTBS on aggression in healthy adults, forensic, and clinical samples. The specific stimulation target is a key factor for the success of stimulation on aggression modulation. rTMS and cTBS showed opposite effects on aggression compared with tDCS. However, due to the heterogeneity of stimulation protocols, experimental designs, and samples, we cannot exclude other factors that may play a confounding role.

A Laboratory Test of Alcohol-Related Intimate Partner Aggression: Expectancies Are Not to Blame

Background: The role of alcohol expectancies and evaluations (i.e., perceived outcomes of drinking and whether these outcomes are desirable) in alcohol-related intimate partner aggression (IPA) has been debated, with some researchers arguing that expectancies fully account for the alcohol-IPA relationship and others suggesting they play a minimal if any role in alcohol-related IPA. In the current study, we examine the impact of expectancies and evaluations on alcohol-related IPA observed in the lab, in order to clarify what impact, if any, alcohol expectancies have on alcohol-related IPA. Consistent with findings from laboratory studies examining general aggression, we expected that individuals who were intoxicated would display greater IPA than individuals who were sober, but that alcohol expectancies and evaluations would be unrelated to in vivo IPA. Method: Participants were 69 dating couples (total N = 138), randomly assigned to consume either an alcohol or placebo beverage. IPA was measured with an in vivo aggression task based on the Taylor Aggression Paradigm. Results: As expected, alcohol intoxication predicted in vivo IPA following provocation (p < .03), whereas alcohol expectancies and evaluations were not related to IPA. Conclusions: These findings provide further support that alcohol expectancies and evaluations play little if any role in alcohol-related IPA. Rather, intoxication likely increases risk for IPA through its physiological effects on perception and thought. Further, treatments targeting alcohol use, rather than beliefs about outcomes of drinking, may have a greater impact on alcohol-related IPA.

Emotion regulation and intimate partner violence perpetration: A meta-analysis

Intimate partner violence (IPV) is a significant public health concern that affects millions of individuals each year. As such, research informing its prediction and prevention is paramount. Etiological models of IPV perpetration and empirical findings suggest that emotion regulation (ER) is associated with IPV perpetration. Further, research has suggested that depending on ER conceptualization, ER may predict either increased (e.g., risk factor) or decreased IPV perpetration (e.g., protective factor). Despite its documented association with IPV perpetration, and amenability to intervention, ER's aggregate association with IPV perpetration has not been evaluated. The present systematic review and meta-analysis analyzes ER's association with IPV perpetration. Two hundred and sixty-five effect sizes from 62 unique samples were included for analysis. Results suggested a small to moderate association between ER and IPV perpetration, the magnitude of which varied by ER construct, whether ER predicted increased or decreased IPV perpetration, and the type of IPV perpetration measured. The magnitude of association between ER and IPV perpetration did not vary by sample type or gender. Implications of these findings were reviewed in the context of meta-theoretical and clinically-focused models of IPV perpetration and suggestions for future research were explored.

Twelve weeks of self-control training does not reduce aggression

Self-control training (SCT) is a method of practicing self-controlled behavior in one domain that enhances self-controlled behavior in additional domains. We investigated whether 4 and 12 weeks of practicing self-control would improve control over aggressive behavior. Relative to the active control group, SCT did not reduce aggression regardless of the training duration. We also did not find supportive evidence to suggest that theoretically relevant variables mediated or moderated the effects of SCT on aggression over time. Bayesian analyses showed greater support for the null hypotheses than the alternative hypothesis. Our experiment casts doubt on the long-term effectiveness of using SCT for reducing reactive aggression. Additional research is necessary to identify the conditions under which SCT is most likely to facilitate control over aggressive behavior.

The hot and the cold in destructive leadership: Modeling the role of arousal in explaining leader antecedents and follower consequences of abusive supervision versus exploitative leadership

Due to its devastating consequences, research needs to theoretically and empirically disentangle different sub-types of destructive leadership. Based on concepts derived from aggression research distinguishing re- and proactive aggression, we provide a process model differentiating abusive supervision and exploitative leadership. High versus low arousal negative affect is installed as the central mediating factor determining (1) whether perceived goal-blockage (leadership antecedents) leads to abusive supervision versus exploitative leadership and (2) whether a specific leadership behavior leads to active versus passive follower behavior (leadership consequence). Further, theoretical anchoring of individual and contextual moderators onto the model's process paths is provided and exemplary hypotheses for concrete moderation effects are deduced. Based on the provided process model, we highlight four recommendations to facilitate process-based construct differentiation in future research on destructive leadership. To precisely understand the differences and commonalities in different forms of destructive leadership will ultimately enable custom-tailored inter- and prevention.

Plain Language Summary

Negative leadership—also named “destructive” leadership—has very bad effects on followers and organizations. There are not just one, but many forms of destructive leadership and it is important to understand where different sub-types come from (i.e., to understand their antecedents) and which specific effect they have (i.e., to understand their consequences). In this paper, we focus on better understanding two forms of destructive leadership, namely abusive supervision and exploitative leadership. These two forms are similar to the two main forms of aggression. Abusive supervision is similar to reactive aggression, an impulsive “hot blooded” form of aggression. Exploitative leadership is similar to proactive aggression, a premeditated “cold blooded” form of aggression. We explain the parallels between the two forms of aggression and the two forms of leadership and provide a model which allows to predict when one versus the other form of leadership occurs and to which follower behavior they lead. An important factor in this model is the physiological characteristic of the emotional reaction to an event (i.e., arousal). An emotional reaction can be high in arousal; for instance, anger is a high arousal negative emotional reaction. On the contrary, boredom, for instance, is a low arousal negative emotional reaction. Dependent on whether both a leader and a follower react to a negative event (e.g., not getting what they want, being treated badly by others) with high or low arousal, their behavior will be different. We explain how this mechanism works and how it can help us to better predict leaders' and followers' behavior. We also outline how individual characteristics of the leader and follower and characteristics of their environment and context interact with arousal and their behavior.

The satisfaction is mine: revenge seeking following extrinsic reward

The extrinsic reward should impede revenge-seeking if revenge is solely driven by the desire to feel gratified. Study 1 (N = 114) showed that satisfaction from receiving monetary compensation decreased thinking about getting back at the provocateur. However, Study 2 (N = 213) found that insulted participants aggressed against their partners despite fulfillment from receiving the unexpected monetary reward. This evidence indicates that gratification is insufficient to impede revenge following provocation, suggesting that avengers want to feel pleasure when retaliating and want to balance the scales by sending offenders a message.

Direct and displaced aggression after exclusion: role of gender differences

The present studies consider the influence of exclusion on aggressive behavior depending on the target of the aggression and the gender of the aggressor. Previous studies have shown that after exclusion, aggressive behavior occurs toward the excluder as well as toward innocent bystanders. However, there is also evidence that men have a greater tendency toward direct aggression and women have a greater tendency toward displaced aggression. In Studies 1 (N = 89) and 2 (N = 120), participants were ostracized, in Studies 3 (N = 88) and 4 (N = 133), participants were rejected. Then, aggressive behavior toward the excluder or bystander was measured. The results confirmed the gender differences hypothesis, but only in the case of ostracism. After ostracism, more retaliatory aggression was observed in men, and more displaced aggression was noted in women. Rejection resulted in generalized aggressive behavior directed toward the excluder and the bystander in men and women. The results are discussed in light of Sexual Selection Theory.

Illicit drug use and violence

This chapter reviews evidence on the relationship between illicit drug use and violence, specifically cannabis, stimulant drugs, and opioids. It summarizes findings of systematic reviews of evidence on cannabis, stimulant drugs, and opioids. It also examines evidence from epidemiological studies of drug use among violent offenders and of violence among persons who use drugs, intervention studies, animal studies, human laboratory studies, and human neuroimaging studies. More studies have examined cannabis because of its higher prevalence of use. There is an association between cannabis use and violence, suggestive evidence of a dose-response relationship between the frequency of cannabis use and violence, and a stronger association in persons with psychoses. There is similar emerging evidence on stimulant use and violence, but evidence on opioids is very limited. There is limited and mixed evidence from intervention studies that reducing drug use reduces violence. Animal and human studies provide potential biological explanations for these associations. The association between cannabis use and violence is most consistent but limited by study heterogeneity and lack of control for potential confounders. It is unclear whether these associations are causal or reflect reverse causation or the effects of confounding.

Effect of subjective sleep quality on aggression: A two-year longitudinal and fMRI pilot study

BACKGROUND/OBJECTIVE

To examine the causal relationship between sleep quality and aggression and their reliable cognitive neural mechanisms.

METHOD

We conducted two follow-up measures on subjective sleep quality, aggression, and resting-state functional magnetic resonance imaging (rs-fMRI) of 455 college students, with a two-year interval between the two follow-up measures. We used cross-lag model on the questionnaire and amplitude of low-frequency fluctuation (ALFF) on rs-fMRI for data analysis.

RESULTS

1) The cross-lag model showed that sleep quality at the first time could predict aggression at the second time. 2) ALFF showed poor sleep quality decreased spontaneous activity in prefrontal regions, but increased activity in limbic system regions, which may be the possible neural basis linking poor sleep quality with increased aggressive behavior.

CONCLUSIONS

There is a causal relationship between subjective sleep quality and aggressive behavior. Our finding proposes a new view of how sleep quality affects aggressive behavior.

The Relation Between the Power of Prefrontal Gamma in Rest-state EEG Under Normal Sleep and Reactive Aggression Behaviour After Sleep Deprivation

Whether sleep deprivation affects aggressive behaviour is still under debate. The present study examined the influence of individual differences in reactive aggressive behaviour after sleep deprivation and preliminarily explored an electrophysiological marker to identify individuals with more aggressive behaviour after sleep deprivation. Thirty participants performed the Taylor Aggression Paradigm task under two sleep conditions: normal sleep (NS, one night of regular sleep) and total sleep deprivation (SD, 30 h of wakefulness), and 5-minute resting-state electroencephalogram (EEG) acquisition was completed under the NS condition. The results found that although sleep deprivation did not have significant effects on aggressive behaviour in the overall analysis, the participants can be classified as an increased group (n = 16) and a no-increased group (n = 14) by different changes in the two sleep conditions (SD-NS). In addition, prefrontal gamma (γ) power was significantly lower in the increased group than in the no-increased group, which may reflect the difference in ability on inhibition. Furthermore, more critical is that γ power was significantly negatively correlated with change in the reactive aggressive behaviour. These results indicate that the effect of SD on reactive aggression varies between individuals, and prefrontal γ power may be an effective electrophysiological marker for identifying people at risk of aggressive behaviour after SD.

Brain responses in aggression-prone individuals: A systematic review and meta-analysis of functional magnetic resonance imaging (fMRI) studies of anger- and aggression-eliciting tasks

Reactive aggression in response to perceived threat or provocation is part of humans' adaptive behavioral repertoire. However, high levels of aggression can lead to the violation of social and legal norms. Understanding brain function in individuals with high levels of aggression as they process anger- and aggression-eliciting stimuli is critical for refining explanatory models of aggression and thereby improving interventions. Three neurobiological models of reactive aggression - the limbic hyperactivity, prefrontal hypoactivity, and dysregulated limbic-prefrontal connectivity models - have been proposed. However, these models are based on neuroimaging studies involving mainly non-aggressive individuals, leaving it unclear which model best describes brain function in those with a history of aggression. We conducted a systematic literature search (PubMed and Psycinfo) and Multilevel Kernel Density meta-analysis (MKDA) of nine functional magnetic resonance imaging (fMRI) studies (eight included in the between-group analysis [i.e., aggression vs. control groups], five in the within-group analysis). Studies examined brain responses to tasks putatively eliciting anger and aggression in individuals with a history of aggression alone and relative to controls. Individuals with a history of aggression exhibited greater activity in the superior temporal gyrus and in regions comprising the cognitive control and default mode networks (right posterior cingulate cortex, precentral gyrus, precuneus, right inferior frontal gyrus) during reactive aggression relative to baseline conditions. Compared to controls, individuals with a history of aggression exhibited increased activity in limbic regions (left hippocampus, left amygdala, left parahippocampal gyrus) and temporal regions (superior, middle, inferior temporal gyrus), and reduced activity in occipital regions (left occipital cortex, left calcarine cortex). These findings lend support to the limbic hyperactivity model in individuals with a history of aggression, and further indicate altered temporal and occipital activity in anger- and aggression-eliciting conditions involving face and speech processing.

The centrality of cognition and coping styles in driving aggressive responses

OBJECTIVE

Despite the presence of theoretical frameworks explaining aggression, they still require refinement in the form of a specification of mechanisms that facilitate such behaviour.

METHOD

Study 1 recruited participants (N = 31) from the general population (N = 20) and from a forensic hospital (N = 11). It was expected that aggression supportive cognitions and stress would be positively associated with aggressive behaviour. An experimental paradigm was used to induce stress and participants were subsequently given the opportunity to aggress. Study 2 was based on self-report questionnaires in community sample (N = 462). It was expected that aggressive behaviour and traits would be associated with experienced stress, hostile attributions, coping styles, and attitudes to violence. Specifically, that criminal attitudes to violence will mediate the effect of hostile attribution on aggression, while coping styles will mediate the effect of perceived stress.

RESULTS

An Implicit Theory "I am the law" was found to be associated with aggression. Furthermore, elevated skin conductance, but not changes in the heart rate, during the stress task was positively associated with aggression, and only among patients. Structural Equation Model confirmed the mediating role of criminal attitudes to violence and of maladaptive coping style for aggressive behaviour.

CONCLUSION

Aggression-supportive cognitions and maladaptive coping style are specific mechanisms through which external demands or subjective perception of a situation can result in aggressive behaviour.

Dissociation of behavioral and neural responses to provocation during reactive aggression in healthy adults with high versus low externalization

The externalizing spectrum describes a range of heterogeneous personality traits and behavioral patterns, primarily characterized by antisocial behavior, disinhibition, and substance (mis)use. In psychopathology, abnormalities in neural threat, reward responses and the impulse-control system may be responsible for these externalizing symptoms. Within the non-clinical range, mechanisms remain still unclear. In this fMRI-study, 61 healthy participants (31 men) from the higher versus lower range of the non-clinical variation in externalization (31 participants with high externalization) as assessed by the subscales disinhibition and meanness of the Triarchic-Psychopathy-Measure (TriPM) performed a monetary modified Taylor-Aggression-Paradigm (mTAP). This paradigm consisted of a mock competitive-reaction-time-task played against a fictional opponent with preprogrammed win- and lose-trials. In lose-trials, participants were provoked by subtraction of an amount of money between 0 and 90 cents. As a manipulation check, provocation induced a significant rise in behavioral aggression levels linked with an increased activation in the anterior cingulate cortex (ACC). High externalization predicted reduced ACC responses to provocation. However, high externalizing participants did not behave more aggressively than the low externalization group. Additionally, the high externalizing group showed a significantly lower positive affect while no group differences emerged for negative affect. In conclusion, high externalization in the non-clinical range was related to neural alterations in regions involved in affective decision-making as well as to changes in affect but did not lead to higher behavioral aggression levels in response to the mTAP. This is in line with previous findings suggesting that aberrations at multiple levels are essential for developing externalizing disorders.

Associations Between Psychopathic Traits and Laboratory-Based Aggression: Moderating Effects of Provocation and Distraction

There are two distinct combinations of psychopathic traits (primary and secondary) that have been proposed to be a function of unique cognitive-affective deficits. This study sought to use theories of psychopathy to understand the factors that exacerbate (i.e., provocation) and attenuate (i.e., distraction) aggression in individuals high in psychopathic traits in a controlled laboratory task. Male undergraduates, who scored across the range of primary and secondary psychopathic traits, completed the Taylor Aggression Paradigm (TAP; Taylor, 1967) under conditions of low and high provocation. Participants were also randomly assigned to either a distraction condition, in which they completed a distracting concurrent task, or a control condition, in which no such task was completed. Inconsistent with our prediction, results showed that regardless of condition, primary psychopathic traits were positively related to laboratory aggression. Consistent with our hypothesis, a positive association between secondary psychopathic traits and laboratory physical aggression was observed following high provocation among nondistracted participants; this association was significantly reduced among distracted participants. These results clarify the factors that contribute to aggression for individuals high in psychopathic traits and may provide directions for future intervention development.

Stress and Violence in Video Games: Their Influence on Aggression

This study investigated whether stress or violent content in video games plays a greater role in aggressiveness towards a cooperative partner while playing a video game. It was hypothesized that participants, when exposed to stress, would demonstrate greater aggressiveness toward an incompetent partner than a competent partner. Furthermore, it was hypothesized that participants, when exposed to a violent video game, would demonstrate greater aggression toward an incompetent partner than those exposed to a non-violent video game. Stress was provoked in half of the participants using the Paced Auditory Serial Addition Test (PASAT), while others took a simple math quiz. Participants were then assigned to a video game condition, violent or non-violent with a competent or incompetent confederate and completed a reaction time task to measure aggression. Results indicated that provoked stress and violent content are not linked to aggression in this context.

A randomized controlled trial examining the effects of intranasal oxytocin on alcohol craving and intimate partner aggression among couples

BACKGROUND

While alcohol use disorder (AUD) is a well-established risk factor for intimate partner aggression (IPA), effective treatments for co-occurring AUD and IPA (AUD/IPA) are lacking. Oxytocin is one promising pharmacological candidate for AUD/IPA given its potential to modulate social behavior and attenuate alcohol use. However, emerging data suggests that oxytocin's prosocial effects are inconsistent, and a small number of studies have also found that oxytocin might have the potential to be aggressogenic. No studies have directly examined the impact of oxytocin on alcohol- or IPA-related outcomes in a dyadic context.

METHODS

The goal of this double-blind, randomized, and placebo-controlled trial was to examine the effects of a single dose of intranasal oxytocin (40 international units) on cue-induced alcohol craving, subjective aggression, laboratory task-based IPA, and cortisol reactivity in a sample of 100 couples (N = 200 individuals) with AUD and physical IPA in their current relationship.

RESULTS

There were no statistically significant differences between the oxytocin and placebo conditions for any of the primary outcomes.

CONCLUSIONS

Findings suggest that a single dose of intranasal oxytocin was not efficacious in mitigating alcohol craving or aggression in this sample. Although hypotheses were not supported, the findings provide important evidence that oxytocin was not aggressogenic in this high-risk sample. Future research investigating dispositional and contextual moderators of oxytocin response in addition to the therapeutic effects of more intensive oxytocin dosing or administration strategies on alcohol craving and aggression is warranted.

Control Yourself: Broad Implications of Narrowed Attention

Attention represents a key element of self-control, and multiple theoretical accounts have highlighted the role played by abundant attentional capacity in effecting successful self-regulation. What, then, are the consequences of living in today's world, in which attention can become so easily divided by a multitude of stimuli? In this article, we consider the implications of divided attention for self-control and show that although the end result is typically disinhibited behavior, under specified conditions, attentional limitation, or what we term attentional myopia, can be associated with enhanced restraint.

Gender Differences in the Relationship between Anger and Aggressive Behavior

Evidence is mixed regarding differences in prevalence of aggressive behavior, with many (though not all) studies suggesting that men are more aggressive than women. Furthermore, while aggression often occurs in response to provocation-induced anger, this relationship may be stronger for men; women may be more likely to engage in non-aggressive (e.g., affiliative) behaviors in response to provocation, particularly at low-level provocation. This study examined gender differences in aggression as well as differences in the relationship between anger and aggression for men and women. Adults (N = 424) participated in a behavioral aggression task, and a subset of participants (n = 304) completed a questionnaire assessing trait levels of anger as part of a larger study at a large midwestern university. Results indicated that while men and women aggressed at similar levels, aggression was significantly associated with trait anger for men only, at low levels of provocation, with only a trending relationship for high provocation. This suggests that while men and women may be equally aggressive in certain situations, this behavior may be differentially associated with anger.

Gender differences in aggression: A multiplicative function of outward anger expression

Individuals with a higher (vs. lower) tendency to outwardly express anger (i.e., greater anger-out) generally exhibit greater aggression; men (vs. women) also tend to be more aggressive. Although the general aggression model posits that multiple person variables trigger aggression, the combined effects of multiple person variables are poorly understood. Thus, the aim of this study was to examine the nature of the relation between gender, anger-out, and reactive aggression. In particular, we were interested in whether the effects of anger-out and gender are additive or multiplicative. Specifically, we tested whether men exhibit higher levels of aggression than women at a consistent ratio across all levels of anger-out (i.e., the multiplicative model) or at a fixed amount depending on the level of anger-out (i.e., the additive interaction model). To this end, undergraduate participants (N = 203) completed a task in which they were falsely instructed that their objective was to respond more quickly than a same-sex opponent. They were told that whoever responded more quickly would administer a white noise burst to the opponent and choose its intensity, which served as our measure of aggression. Compared to an additive interaction model, the multiplicative model exhibited a better fit. Specifically, men displayed proportionately more aggression than women with the same level of anger-out. Research on and treatment for aggression should consider the multiplicative effects of factors related to aggression.

Glucocorticoids and Aggression: A Tripartite Interaction

The effects of glucocorticoids on aggression can be conceptualized based on its mechanisms of action. These hormones can affect cell function non-genomically within minutes, primarily by affecting the cell membrane. Overall, such effects are activating and promote both metabolic preparations for the fight and aggressive behavior per se. Chronic increases in glucocorticoids activate genomic mechanisms and are depressing overall, including the inhibition of aggressive behavior. Finally, excessive stressors trigger epigenetic phenomena that have a large impact on brain programming and may also induce the reprogramming of neural functions. These induce qualitative changes in aggression that are deemed abnormal in animals, and psychopathological and criminal in humans. This review aims at deciphering the roles of glucocorticoids in aggression control by taking in view the three mechanisms of action often categorized as acute, chronic, and toxic stress based on the duration and the consequences of the stress response. It is argued that the tripartite way of influencing aggression can be recognized in all three animal, psychopathological, and criminal aggression and constitute a framework of mechanisms by which aggressive behavior adapts to short-term and log-term changes in the environment.

Do High-Risk Parents Use More Aggression During Competitive Play With Children?

The present study examined the extent to which the aggressive tendencies of parents at risk for perpetrating child physical abuse (CPA) generalize to situations other than discipline-related encounters (e.g., a competitive gaming interaction). Participants included parents who were either low (n = 90) or high (n = 75) risk for CPA. Parents were led to believe that they were playing a game against a child opponent with whom they exchanged sound blasts of varying intensities. Parental sound blast selections served as a proxy for aggressive behavior. Parents were randomly assigned to high or low loss conditions. The fictitious child opponent's responses were pre-programed so that sound blasts received by parents became louder (i.e., more provocative) over time. As predicted, high CPA risk parents exhibited higher levels of aggression than low CPA risk parents. Moreover, high-risk parents reported having higher levels of aggressive motives during the game than low-risk parents; and aggressive motives explained the link between parental CPA risk and parents' aggressive behavior. With one exception, higher levels of child provocation during the game prompted parents to send higher levels of sound blasts. The exception to this pattern occurred among low-risk parents who experienced high rates of loss during the game. Specifically, low-risk parents in the high loss condition continued to send low levels of sound blasts even as their child opponent became more provocative. Aggressive motives (and the ability to change motives as situations change) may help explain differences in aggressive tendencies evinced by parents with varying levels of CPA risk.

An empirically based power primer for laboratory aggression research

Recent reviews suggest that, like much of the psychological literature, research studies using laboratory aggression paradigms tend to be underpowered to reliably locate commonly observed effect sizes (e.g., r = ~.10-.20, Cohen's d = ~0.20-0.40). In an effort to counter this trend, we provide a "power primer" that laboratory aggression researchers can use as a resource when planning studies using this methodology. Using simulation-based power analyses and effect size estimates derived from recent literature reviews, we provide sample size recommendations based on type of research question (e.g., main effect vs. two-way vs. three-way interactions) and correlations among predictors. Results highlight the large number of participants that must be recruited to reach acceptable (~80%) power, especially for tests of interactions where the recommended sample sizes far exceed those typically employed in this literature. These discrepancies are so substantial that we urge laboratory aggression researchers to consider a moratorium on tests of three-way interactions. Although our results use estimates from the laboratory aggression literature, we believe they are generalizable to other lines of research using behavioral tasks, as well as psychological science more broadly. We close by offering a series of best practice recommendations and reiterating long-standing calls for attention to statistical power as a basic element of study planning.

Reactive vs proactive aggression: A differential psychobiological profile? Conclusions derived from a systematic review

INTRODUCTION

Scholars have established subcategories of aggressive behavior in order to better understand this construct. Specifically, a classification based on motivational underpinnings makes it possible to differentiate between reactive and proactive aggression. Whereas reactive aggression is characterized by emotional lability, which means it is prone to impulsive reactions after provocation, proactive aggression is driven by low emotionality and high levels of instrumentality to obtain benefits. Some authors have conceived these two types as having a dichotomous nature, but others argue against this conceptualization, considering a complementary model more suitable. Hence, neuroscientific research might help to clarify discussions about their nature because biological markers do not present the same biases as psychological instruments.

AIM

The main objective of this study was to carry out a systematic review of studies that assess underlying biological markers (e.g., genes, brain, psychophysiological, and hormonal) of reactive and proactive aggression.

METHODS

To carry out this review, we followed PRISMA quality criteria for reviews, using five digital databases complemented by hand-searching.

RESULTS

The reading of 3993 abstracts led to the final inclusion of 157 papers that met all the inclusion criteria. The studies included allow us to conclude that heritability accounted for approximately 45% of the explained variance in both types of aggression, with 60% shared by both, especially, for overt and physical expression forms, and 10% specific to each type. Regarding allelic risk factors, whereas low functioning variants affecting serotonin transport and monoaminoxidase increased the risk of reactive aggression, high functioning variants were associated with proactive aggression. Furthermore, brain analysis revealed an overlap between the two types of aggression and alterations in the volume of the amygdala and temporal cortex. Moreover, high activation of the medial prefrontal cortex (PFC) facilitated proneness to both types of aggression equally. Whereas stimulation of the right ventrolateral (VLPFC) and dorsolateral (DLPFC) reduced proneness to aggression, inhibition of the left DLPFC increased it. Finally, psychophysiological and hormonal correlates in general did not clearly differentiate between the two types because they were equally related to each type (e.g., low basal cortisol and vagal variability in response to acute stress) CONCLUSIONS: This study reinforces the complementary model of both types of aggression instead of a dichotomous model. Additionally, this review also offers background about several treatments (i.e., pharmacological, non-invasive brain techniques…) to reduce aggression proneness.

Online Crowdsourcing as a Quasi-Experimental Method for Collecting Data on the Perpetration of Alcohol-Related Partner Aggression

Cross-sectional survey, prospective, and experimental data have been evaluated to better understand the role of alcohol as a contributing cause of intimate partner aggression. Laboratory-based alcohol administration studies provide controlled data regarding causality, but the use of this methodology lacks ecological validity and has been hampered by rigorous procedural and financial demands. Online crowdsourcing is an emerging pseudoexperimental methodology with low costs, rapid data collection, access to diverse populations, greater ecological validity, and the potential to facilitate prolific research to supplement the chronic scarcity of experimental data. The current rapid review first summarizes prior methodological approaches to investigating the proximal influence of alcohol on partner aggression, then reviews prior crowdsourcing research in the disparate areas of alcohol and partner aggression, then describes aggression paradigms that may be readily adapted to online administration. We conclude by introducing recommendations for future quasi-experimental research investigating alcohol-related partner aggression research using the online crowdsourcing methodology. Initial evidence suggests that online crowdsourcing may yield appropriate samples and that existing paradigms may be adapted to rapidly, efficiently, and ethically supplement experimental alcohol-related partner aggression research.

Non-invasive neuromodulation can reduce aggressive behaviors in humans: A critical perspective

Containing aggressive behavior is an ongoing challenge in modern society. Aggressiveness is a multi-level construct that can be driven by emotions (reactive aggression) or can be "cold-blooded" and goal-directed (proactive). Aggressive behavior could arise because of a misjudgment of others' intentions or can follow frontal brain lesions leading to a reduction of impulse control and emotion regulation. In the last few years, interventional and basic research studies adopting Non-Invasive Brain Stimulation (NIBS) have significantly risen. Those techniques have been used both in healthy people, to better understand the role of certain brain regions in psychological processes, and in aggressive subjects to improve their symptoms. From an overview of the literature, focusing on the paper that uses transcranial direct current stimulation (tDCS) to reduce aggressiveness, it emerges that tDCS can (i) enhance facial emotion expression recognition, (ii) improve impulses control, and (iii) affect approach/withdrawal motivation. The current work shows the strengths and weaknesses of tDCS intervention on aggressive individuals, suggesting that this instrument could be adopted on violent people, and paves the way for intervention in some applied settings such as prison.

Modulating Behavioural and Self-Reported Aggression with Non-Invasive Brain Stimulation: A Literature Review

Aggressive behaviour is at the basis of many harms in society, such as violent crime. The efforts to explain, study, and possibly reduce aggression span various disciplines, including neuroscience. The specific brain networks which are involved in the modulation of aggressive behaviour include cortical asymmetry and brain areas such as the dorsolateral prefrontal cortex (DLPFC), the ventrolateral prefrontal cortex (VLPFC), and the ventromedial prefrontal cortex (VMPFC). Recent non-invasive brain stimulation (NIBS) research suggests that both transcranial direct current stimulation (tDCS) and continuous theta burst stimulation (cTBS) can play a role in the modulation of aggressive behaviour by directly changing brain activity. In this review, we systematically explore and discuss 11 experimental studies that aimed to modulate aggressive behaviour or self-reported aggression using NIBS. Out of these 11 studies, nine significantly up- or downregulated aggression by using tDCS or cTBS targeting the DLPFC, VLPFC or VMPFC. The potential applications of these findings span both the clinical and the forensic psychological domains. However, the results are limited by the methodological heterogeneity in the aggression measures used across the studies, and by their generally small sample sizes. Future research should consider improving the localization and specificity of NIBS by employing neuro-navigational instruments and standardized scoring methods.

Impulsivity and Perpetration of Intimate Partner Aggression: The Moderating Effects of Negative Affective State and Alcohol

Background: The goal of this study was to test the interactive effects of negative urgency, state negative affect, and alcohol intoxication on intimate partner aggression (IPA) perpetration. Methods: Heavy drinkers who recently perpetrated IPA completed self-report measures of impulsivity, were administered an alcohol or control beverage, and completed a laboratory aggression task. State negative affect was assessed unobtrusively via the Facial Action Coding System. Results: Consistent with our prediction, negative urgency was significantly and positively related to IPA when state negative affect was also high, but this relation was not significant when state negative affect was low. Conclusions: These results have implications for understanding the role of negative affect and impulsivity in IPA perpetration and for understanding trait models of impulsivity in general.

Psychobiological Correlates of Aggression in Female Adolescents with Borderline Personality Disorder

INTRODUCTION

Aggressive behavior in reaction to threats, frustration, or provocation is prevalent in borderline personality disorder (BPD). This study investigated aggressive behavior and its biological correlates in adolescents with BPD.

METHODS

Twenty-one female adolescents with a DSM-IV BPD diagnosis and 25 sex- and age-matched healthy controls participated in the Taylor Aggression Paradigm (TAP), a laboratory-based experiment measuring aggressive behavior in the interpersonal context. Heart rate was measured and saliva samples were taken throughout the experiment.

RESULTS

Multilevel mixed-effects linear regression analyses revealed no significant group difference in aggressive behavior induced by the TAP. Additionally, the two groups did not differ in cortisol, testosterone, and heart rate responses to the aggression induction. The BPD group showed a significant cortisol increase in the time preceding the start of the TAP in contrast to the healthy control group, in whom a significant heart rate increase from baseline to the first block of the TAP was observed.

DISCUSSION

There was no evidence, either at the phenomenological or the biological level, of increased task-induced aggression in adolescents with BPD. The results may indicate that adolescents with BPD experienced fearful stress in anticipation of the experimental task in contrast to healthy controls who showed an adaptive response of the autonomic nervous system necessary to deal with the upcoming demand.

Effects of Angry Rumination and Distraction in Intimate Partner Violent Men

Although the tendency to ruminate is related to the frequency of intimate partner violent (IPV) perpetration, it is unclear how IPV men react emotionally and physiologically during angry rumination. This study is the first to experimentally manipulate rumination and distraction with violent men. Using the rumination and distraction paradigm developed by Nolen-Hoeksema and Morrow, IPV (N = 87) and nonviolent (NV; N = 30) men underwent an anger induction and then were randomly assigned to either ruminate or distract. IPV men were hypothesized to experience increased effects of rumination compared to NV men. As predicted, the results demonstrate an increase in heart rate from baseline to postrumination. No change in physiological arousal was observed in the distraction condition over time. Surprisingly, no difference state anger was found between IPV and NV men, and both conditions resulted in an increase in state anger. Implications for battering interventions suggest that distraction strategies, such as taking a time-out, are not sufficient to decrease physiological arousal. Intervention strategies that address mindfulness, physiological soothing, distorted cognitions, and rumination may be more powerful in decreasing negative physiological arousal among IPV men.

A meta-analysis on shared and distinct neural correlates of the decision-making underlying altruistic and retaliatory punishment

Individuals who violate social norms will most likely face social punishment sanctions. Those sanctions are based on different motivation aspects, depending on the context. Altruistic punishment occurs if punishment aims to re‐establish the social norms even at cost for the punisher. Retaliatory punishment is driven by anger or spite and aims to harm the other. While neuroimaging research highlighted the neural networks supporting decision‐making in both types of punishment in isolation, it remains unclear whether they rely on the same or distinct neural systems. We ran an activation likelihood estimation meta‐analysis on functional magnetic resonance imaging data on 24 altruistic and 19 retaliatory punishment studies to investigate the neural correlates of decision‐making underlying social punishment and whether altruistic and retaliatory punishments share similar brain networks. Social punishment reliably activated the bilateral insula, inferior frontal gyrus, midcingulate cortex (MCC), and superior and medial frontal gyri. This network largely overlapped with activation clusters found for altruistic punishment. However, retaliatory punishment revealed only one cluster in a posterior part of the MCC, which was not recruited in altruistic punishment. Our results support previous models on social punishment and highlight differential involvement of the MCC in altruistic and retaliatory punishments, reflecting the underlying different motivations.