Surveillance of Gun-Related Conversations on Twitter.

Gun violence in the USA is a documented public health crisis. Publicly accessible data from Twitter posts can be used to rapidly capture and describe the public's recent conversations about guns. Because these gun-related conversations change rapidly, it is important to provide regularly updated information on them. Twitter posts containing gun-related terms were obtained from January 1, 2022 to June 30, 2022. To understand topics of gun-related tweets (N = 449,492), topic modeling was performed with Top2Vec. Gun ownership control, concern about gun safety and its impact on children and schools, and the Second Amendment were major areas of the gun-related discourse on Twitter. Several identified topics in this study were a consequence of the study period, including "Discourse on Capitol Riots," and "Wartime and Military Use of Guns," with the latter topic containing conversations about the Russia-Ukraine War. Conversations around the influence of the National Rifle Association (NRA) on gun policies and pro-gun ownership perspectives were also part of the public discourse. The intersection between alcohol, substance use, and gun use was infrequently observed. Findings suggest that gun-related conversations in social media such as Twitter can inform public health researchers.

Evolution, culture, and the possibility of peace.

Glowacki's work meshes well with our view of human nature as having evolved to use culture to improve survival and reproduction. Peace is a cultural achievement, requiring advances in social organization and control, including leaders who can implement policies to benefit the group, third-party mediation, and intergroup cooperation. Cultural advances shift intergroup interactions from negative-sum (war) to positive-sum (trade).

Within-Person Bidirectional Associations Over Time Between Parenting and Youths' Callousness.

OBJECTIVE: Callousness has been identified as a key driver of aggressive and violent behavior from childhood into early adulthood. Although previous research has underscored the importance of the parenting environment in contributing to the development of youth callousness, findings have generally been confined to the between-individual level and have not examined bidirectionality. In the current study, we test whether aspects of parenting are associated with callousness from childhood to adolescence both between and within individuals, examine the temporal ordering of associations, and test whether these relations are moderated by gender or developmental stage. METHOD: Data came from a longitudinal study in which parents of 1,421 youth (52% girls; 62% White and 22% Black) from the second, fourth, and ninth grades were interviewed three times, with one year between consecutive interviews. RESULTS: A random-intercept cross-lagged panel model indicated that elevated youth callousness predicts subsequent increases in parental rejection and decreases in consistency of discipline. Findings were largely similar for boys and girls, but within-individual associations were generally stronger for 4th graders compared to the 2nd and 9th graders. CONCLUSIONS: Callousness and parenting practices and attitudes were related both at the between-individual and within-individual level. These results have implications for the etiology and treatment of children and adolescents who exhibit callousness.

Frustration-aggression hypothesis reconsidered: The role of significance quest.

One of the oldest scientific theories of human aggression is the frustration-aggression hypothesis, advanced in 1939. Although this theory has received considerable empirical support and is alive and well today, its underlying mechanisms have not been adequately explored. In this article, we examine major findings and concepts from extant psychological research on hostile aggression and offer an integrative conception: aggression is a primordial means for establishing one's sense of significance and mattering, thus addressing a fundamental social-psychological need. Our functional portrayal of aggression as a means to significance yields four testable hypotheses: (1) frustration will elicit hostile aggression proportionately to the extent that the frustrated goal serves the individual's need for significance, (2) the impulse to aggress in response to significance loss will be enhanced in conditions that limit the individual's ability to reflect and engage in extensive information processing (that may bring up alternative, socially condoned means to significance), (3) significance-reducing frustration will elicit hostile aggression unless the impulse to aggress is substituted by a nonaggressive means of significance restoration, (4) apart from significance loss, an opportunity for significance gain can increase the impulse to aggress. These hypotheses are supported by extant data as well as novel research findings in real-world contexts. They have important implications for understanding human aggression and the conditions under which it is likely to be manifested and reduced.

Development and Validation of the Single-Item Mindfulness Scale (SIMS).

Mindfulness is a focused attention to and acceptance of present experiences. Although several reliable and valid multi-item measures of trait mindfulness exist, researchers may sometimes want a short and quick measure of mindfulness. In this project, we developed and validated the Single-Item Mindfulness Scale (SIMS) to assess trait mindfulness. We conducted eight studies involving 3,125 adult and adolescent participants. The studies consisted of cross-sectional, short longitudinal, and daily diary designs. We first developed the wording of the SIMS in Studies 1 and 2 and then examined the validity and reliability in Studies 3-8. The SIMS was found to be reliable and valid. It correlated with several multi-item measures of mindfulness at effect sizes in the medium to large range. It also correlated in expected ways with variables known to be related to existing multi-item measures of mindfulness such as self-compassion, anxiety, negative affect, positive affect, depression, neuroticism, empathy, prosocial behavior, and self-consciousness. Furthermore, it correlated positively with daily reports of mindfulness in a two-week diary study. Although existing multi-item trait mindfulness scales should be used, when possible, the SIMS is recommended in situations when time, question quantity, or researcher focus is constrained.

Developmental Changes in the Relation between Youth Disclosure and Parenting Behavior: A Cohort-sequential Analysis.

To address a gap in the literature regarding the development of youth disclosure across the transition to adolescence, the current research uses a cohort-sequential approach to study youth disclosure from middle childhood through adolescence. Longitudinal data from three cohorts of parents were utilized (N = 1359; children at T1 were in grades 2 [M = 8.00 years, SD = 0.57 years, 45% female], 4 [M = 10.12 years, SD = 0.60 years, 45% female], and 9 [M = 15.19 years, SD = 0.57 years, 48% female]). Parents were assessed annually over a 3-year time period. The focal analyses explored contemporaneous associations between characteristics of the parent-youth relationship (specifically, parental rejection and parental consistent discipline) and youth disclosure after accounting for person-specific trajectories of disclosure. Associations of gender, age, and socioeconomic status with disclosure were also assessed. Regarding trajectories of youth disclosure, results indicate that youth disclose less information to their parents about their daily lives as they get older; this trend was consistent across gender and socioeconomic status. In terms of associations with youth disclosure, when parents provided more consistent discipline or engaged in less rejection of their child, youth disclosure increased, even after accounting for their own trajectory of disclosure across time. In addition, the association of consistent discipline with youth disclosure became stronger with increased youth age. Results are discussed in terms of implications for understanding youth autonomy development, and the dyadic and developmental impact of parenting behaviors over time.

Effects of violent and nonviolent sexualized media on aggression-related thoughts, feelings, attitudes, and behaviors: A meta-analytic review.

Women are often depicted as sex objects rather than as human beings in the media (e.g., magazines, television programs, films, and video games). Theoretically, media depictions of females as sex objects could lead to negative attitudes and even aggressive behavior toward them in the real world. Using the General Aggression Model (Anderson & Bushman, 2002) as a theoretical framework, this meta-analytic review synthesizes the literature on the effects of sexualized media (both violent and nonviolent) on aggression-related thoughts, attitudes, and behaviors. Our sample includes 166 independent studies involving 124,236 participants, which yielded 321 independent effects. Overall, the effects were "small" to "moderate" in size (r = .16 [.14-.18]). Significant correlations were found in experimental, cross-sectional, and longitudinal studies, indicating a triangulation of evidence. Effects were stronger for violent sexualized media (r = .25 [.19-.31]) than for nonviolent sexualized media (r = .15 [.13-.17]), although the effects of nonviolent sexualized media were still significant and nontrivial in size. Moreover, the effects of violent sexualized media on aggression were greater than the effects of violent non-sexualized media on aggression obtained in previous meta-analyses. Effects were similar for male and female participants, for college students and non-students, and for participants of all ages. The effects were also stable over time. Sensitivity analyses found that effects were not unduly influenced by publication bias and/or outliers. In summary, exposure to sexualized media content, especially in combination with violence, has negative effects on women, particularly on what people think about them and how aggressively they treat them.

Longitudinal predictions of young adults' weapons use and criminal behavior from their childhood exposure to violence.

In this study, we examine whether youth who are exposed to more weapons violence are subsequently more likely to behave violently with weapons. We use data collected with a 3-cohort, 4-wave, 10-year longitudinal study of 426 high-risk youth from Flint, Michigan, who were second, fourth, or ninth-graders in 2006-2007. The data were obtained from individual interviews with the youth, their parents, and their teachers, from archival school and criminal justice records, and from geo-coded criminal offense data. These data show that early exposure to weapons violence significantly correlates at modest levels with weapon carrying, weapon use or threats-to-use, arrests for weapons use, and criminally violent acts 10 years later. Multiple regression analyses, controlling for children's initial aggressiveness, intellectual achievement, and parents' income, education, and aggression, reveal statistically significant independent 10-year effects: (1) more early exposure to weapon use within the family predicts more using or threatening to use a gun; (2) more cumulative early violent video game playing predicts more gun using or threatening to use weapons, and normative beliefs that gun use is acceptable; (3) more cumulative early exposure to neighborhood gun violence predicts more arrests for a weapons crime; and (4) more cumulative early exposure to movie violence predicts more weapon carrying. We argue that youth who observe violence with weapons, whether in the family, among peers, or through the media or video games, are likely to be infected from exposure with a social-cognitive-emotional disease that increases their own risk of behaving violently with weapons later in life.

"Boom, Headshot!": Violent first-person shooter (FPS) video games that reward headshots train individuals to aim for the head when shooting a realistic firearm.

When shooting a gun at a human target, firearms training instructors teach individuals to shoot for the upper torso because it is the largest lethal target on the human body. In contrast, violent first-person shooter (FPS) video games reward players for headshots. The head is the smallest lethal target, and requires careful aim to hit. In this experiment, participants were randomly assigned to play a violent FPS game with humanoid targets that rewarded headshots, a nonviolent shooting game that punished hits to bull's-eye targets with faces, or a nonviolent non-shooting game. After gameplay, participants shot 16 "bullets" from a realistic gun at a life-sized human-shaped mannequin. Participants were told to hit the mannequin with as many bullets as possible, but they were not told where to aim. Consistent with operant conditioning theory, participants who played a violent FPS game that rewarded headshots had the most hits to the mannequin's head. Participants whose favorite video games were violent shooting games also had the most hits to the mannequin's head. These findings suggest that FPS games that reward headshots can influence people to aim for the head with a realistic gun after the game is turned off, even though the head is a much smaller target to hit and they are much less likely to hit another body part if they miss. FPS games are often used to train soldiers and police officers, but these findings suggest that such games might train individuals to hit the wrong part of the body.

Effects of sexualized video games on online sexual harassment.

Negative consequences of video games have been a concern since their inception. However, one under-researched area is the potential negative effects of sexualized video game content on players. This study analyzed the consequences of sexualized video game content on online sexual harassment against male and female targets. We controlled for a number of variables that might be related to online sexual harassment (i.e., trait aggressiveness, ambivalent sexism, online disinhibition). Participants (N = 211) played a video game with either sexualized or non-sexualized female characters. After gameplay, they had the opportunity to sexually harass a male or a female partner by sending them sexist jokes. Based on the General Aggression Model integrated with the Confluence Model of Sexual Aggression (Anderson & Anderson, ), we predicted that playing the game with sexualized female characters would increase sexual harassment against female targets. Results were consistent with these predictions. Sexual harassment levels toward a female partner were higher for participants who played the game with sexualized female characters than for participants who played the same game with non-sexualized female characters. These findings indicate that sexualization of female characters in a video game can be a sufficient condition to provoke online sexual harassment toward women.

The competitive reaction time task: The development and scientific utility of a flexible laboratory aggression paradigm.

Laboratory measures play an important role in the study of aggression because they allow researchers to make causal inferences. However, these measures have also been criticized. In particular, the competitive reaction time task (CRTT) has been criticized for allowing aggression to be operationalized in multiple ways, leaving it susceptible to "p-hacking." This article describes the development of the CRTT and the ways in which its paradigm flexibility and analytic flexibility allows it to test a wide range of hypotheses and research questions. This flexibility gives the CRTT significant scientific utility, but as with any research paradigm, comes with the obligation that it has to be used with integrity. Although safeguards exist and there is little evidence of misuse, study preregistration can increase confidence in CRTT findings. The importance of findings such as those of Hyatt et al. (in press), which provide further evidence for the validity of the CRTT, are also noted.

Effects of Weapons on Aggressive Thoughts, Angry Feelings, Hostile Appraisals, and Aggressive Behavior: A Meta-Analytic Review of the Weapons Effect Literature.

A landmark 1967 study showed that simply seeing a gun can increase aggression-called the "weapons effect." Since 1967, many other studies have attempted to replicate and explain the weapons effect. This meta-analysis integrates the findings of weapons effect studies conducted from 1967 to 2017 and uses the General Aggression Model (GAM) to explain the weapons effect. It includes 151 effect-size estimates from 78 independent studies involving 7,668 participants. As predicted by the GAM, our naïve meta-analytic results indicate that the mere presence of weapons increased aggressive thoughts, hostile appraisals, and aggression, suggesting a cognitive route from weapons to aggression. Weapons did not significantly increase angry feelings. Yet, a comprehensive sensitivity analysis indicated that not all naïve mean estimates were robust to the presence of publication bias. In general, these results suggest that the published literature tends to overestimate the weapons effect for some outcomes and moderators.

Origins of narcissism in children.

Narcissism levels have been increasing among Western youth, and contribute to societal problems such as aggression and violence. The origins of narcissism, however, are not well understood. Here, we report, to our knowledge, the first prospective longitudinal evidence on the origins of narcissism in children. We compared two perspectives: social learning theory (positing that narcissism is cultivated by parental overvaluation) and psychoanalytic theory (positing that narcissism is cultivated by lack of parental warmth). We timed the study in late childhood (ages 7-12), when individual differences in narcissism first emerge. In four 6-mo waves, 565 children and their parents reported child narcissism, child self-esteem, parental overvaluation, and parental warmth. Four-wave cross-lagged panel models were conducted. Results support social learning theory and contradict psychoanalytic theory: Narcissism was predicted by parental overvaluation, not by lack of parental warmth. Thus, children seem to acquire narcissism, in part, by internalizing parents' inflated views of them (e.g., "I am superior to others" and "I am entitled to privileges"). Attesting to the specificity of this finding, self-esteem was predicted by parental warmth, not by parental overvaluation. These findings uncover early socialization experiences that cultivate narcissism, and may inform interventions to curtail narcissistic development at an early age.

CLASH: Climate (change) and cultural evolution of intergroup conflict.

Aggression and violence levels generally increase as one moves closer to the equator, but why? We developed a new theoretical model, CLimate, Aggression, and Self-control in Humans (CLASH; van Lange, Rinderu, & Bushman, 2017b, 2017c), to understand differences within and between countries in aggression and violence in terms of differences in climate. Colder temperatures, and especially larger degrees of seasonal variation in climate, call for individuals and groups to adopt a slower life history strategy, revealed in a greater focus on the future (vs. present) and a stronger focus on self-control-variables that are known to inhibit aggression and violence. Other variables (e.g., wealth, income inequality, parasite stress) are also linked to both climate differences and to aggression and violence differences. When people think of the consequences of climate change, they rarely think of the impact on aggression and violence levels, but they should. CLASH has broad implications for the effects of climate change on intergroup conflict.

Neuromodulation can reduce aggressive behavior elicited by violent video games.

Research has shown that exposure to violent media increases aggression. However, the neural underpinnings of violent-media-related aggression are poorly understood. Additionally, few experiments have tested hypotheses concerning how to reduce violent-media-related aggression. In this experiment, we focused on a brain area involved in the regulation of aggressive impulses-the right ventrolateral prefrontal cortex (rVLPFC). We tested the hypothesis that brain polarization through anodal transcranial direct current stimulation (tDCS) over rVLPFC reduces aggression related to violent video games. Participants (N = 79) were randomly assigned to play a violent or a nonviolent video game while receiving anodal or sham stimulation. Afterward, participants aggressed against an ostensible partner using the Taylor aggression paradigm (Taylor Journal of Personality, 35, 297-310, 1967), which measures both unprovoked and provoked aggression. Among those who received sham stimulation, unprovoked aggression was significantly higher for violent-game players than for nonviolent-game players. Among those who received anodal stimulation, unprovoked aggression did not differ for violent- and nonviolent-game players. Thus, anodal stimulation reduced unprovoked aggression in violent-game players. No significant effects were found for provoked aggression, suggesting tit-for-tat responding. This experiment sheds light on one possible neural underpinning of violent-media-related aggression-the rVLPFC, a brain area involved in regulating negative feelings and aggressive impulses.

The Contagious Spread of Violence Among US Adolescents Through Social Networks.

OBJECTIVES: To test the hypothesis that violence among US adolescents spreads like a contagious disease through social networks. METHODS: Participants were a nationally representative sample of 90 118 US students aged 12 to 18 years who were involved in the National Longitudinal Study of Adolescent Health. Violence was assessed by having participants report the number of times in the preceding 12 months they had been involved in a serious physical fight, had hurt someone badly, and had pulled a weapon on someone. RESULTS: Participants were 48% more likely to have been involved in a serious fight, 183% more likely to have hurt someone badly, and 140% more likely to have pulled a weapon on someone if a friend had engaged in the same behavior. The influence spread up to 4 degrees of separation (i.e., friend of friend of friend of friend) for serious fights, 2 degrees for hurting someone badly, and 3 degrees for pulling a weapon on someone. CONCLUSIONS: Adolescents were more likely to engage in violent behavior if their friends did the same, and contagion of violence extended beyond immediate friends to friends of friends.

Low glucose relates to greater aggression in married couples.

Intimate partner violence affects millions of people globally. One possible contributing factor is poor self-control. Self-control requires energy, part of which is provided by glucose. For 21 days, glucose levels were measured in 107 married couples. To measure aggressive impulses, each evening participants stuck between 0 and 51 pins into a voodoo doll that represented their spouse, depending how angry they were with their spouse. To measure aggression, participants competed against their spouse on a 25-trial task in which the winner blasted the loser with loud noise through headphones. As expected, the lower the level of glucose in the blood, the greater number of pins participants stuck into the voodoo doll, and the higher intensity and longer duration of noise participants set for their spouse.

Drawn to danger: trait anger predicts automatic approach behaviour to angry faces.

Most people automatically withdraw from socially threatening situations. However, people high in trait anger could be an exception to this rule, and may even display an eagerness to approach hostile situations. To test this hypothesis, we asked 118 participants to complete an approach-avoidance task, in which participants made approach or avoidance movements towards faces with an angry or happy expression, and a direct or averted eye gaze. As expected, higher trait anger predicted faster approach (than avoidance) movements towards angry faces. Crucially, this effect occurred only for angry faces with a direct eye gaze, presumably because they pose a specific social threat, in contrast to angry faces with an averted gaze. No parallel effects were observed for happy faces, indicating that the effects of trait anger were specific to hostile stimuli. These findings suggest that people high in trait anger may automatically approach hostile interaction partners.

Aggression and violence around the world: A model of CLimate, Aggression, and Self-control in Humans (CLASH).

Worldwide there are substantial differences within and between countries in aggression and violence. Although there are various exceptions, a general rule is that aggression and violence increase as one moves closer to the equator, which suggests the important role of climate differences. While this pattern is robust, theoretical explanations for these large differences in aggression and violence within countries and around the world are lacking. Most extant explanations focus on the influence of average temperature as a factor that triggers aggression (The General Aggression Model), or the notion that warm temperature allows for more social interaction situations (Routine Activity Theory) in which aggression is likely to unfold. We propose a new model, CLimate, Aggression, and Self-control in Humans (CLASH), that helps us to understand differences within and between countries in aggression and violence in terms of differences in climate. Lower temperatures, and especially larger degrees of seasonal variation in climate, call for individuals and groups to adopt a slower life history strategy, a greater focus on the future (vs. present), and a stronger focus on self-control. The CLASH model further outlines that slow life strategy, future orientation, and strong self-control are important determinants of inhibiting aggression and violence. We also discuss how CLASH differs from other recently developed models that emphasize climate differences for understanding conflict. We conclude by discussing the theoretical and societal importance of climate in shaping individual and societal differences in aggression and violence.

The Logic of Climate and Culture: Evolutionary and Psychological Aspects of CLASH.

A total of 80 authors working in a variety of scientific disciplines commented on the theoretical model of CLimate, Aggression, and Self-control in Humans (CLASH). The commentaries cover a wide range of issues, including the logic and assumptions of CLASH, the evidence in support of CLASH, and other possible causes of aggression and violence (e.g., wealth, income inequality, political circumstances, historic circumstances, pathogen stress). Some commentaries also provide data relevant to CLASH. Here we clarify the logic and assumptions of CLASH and discusses its extensions and boundary conditions. We also offer suggestions for future research. Regardless of whether none, some, or all of CLASH is found to be true, we hope it will stimulate future research on the link between climate and human behavior. Climate is one of the most presing issues of our time.