Point Subtraction Aggression Paradigm Research Articles

Intermittent escitalopram treatment and reactive aggression in women with premenstrual irritability and anger: A crossover study

BackgroundSSRIs are the primary treatment for premenstrual mood symptoms and particularly effective in reducing reactive aggression in the forms of irritability and anger.The present study examined whether behavioral responses in laboratory measures of reactive aggression are influenced by medication with the SSRI escitalopram in women reporting high levels of premenstrual irritability/anger. MethodsParticipants (N = 34) rated the cardinal mood symptoms of premenstrual dysphoric disorder over three menstrual cycles. During the second and third cycles, participants received escitalopram (20 mg) or placebo in a single-blind, cross-over design. In the luteal phase of the intervention cycles, participants completed two aggression tasks: The Anger-Infused Ultimatum Game (AI-UG) and the Point Subtraction Aggression Paradigm (PSAP). Additionally, they rated expression and control of anger using the State-Trait Anger Expression Inventory-2 (STAXI-2) once in the luteal phase and once in the follicular phase. ResultsWhile irritability/anger was reduced in the treatment (vs. placebo) cycle, no effect of escitalopram was detected in the PSAP. Escitalopram decreased reactive aggressive behavior in the AI-UG but only for a subset of participants who experienced a sharp premenstrual rise in outwardly expressed anger and/or did not experience a premenstrual rise in inwardly expressed anger. LimitationsThe participants' symptoms were based on the severity of only premenstrual irritability/anger, limiting the generalizability to the broader group of PMDD patients. ConclusionThe results suggest that the behavioral consequences of severe premenstrual irritability/anger are not easily captured by traditional measures of reactive aggression and underline the importance of considering individual differences in symptom expression.

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.

Cerebellar Asymmetry of Motivational Direction: Anger-Dependent Effects of Cerebellar Transcranial Direct Current Stimulation on Aggression in Healthy Volunteers.

It has recently been theorized that the frontal asymmetry of approach- and avoidance-related motivation is mirrored in the posterolateral cerebellum. Accordingly, left-to-right dominant cerebellar activity is associated with avoidance-related motivation, whereas right-to-left dominant cerebellar activity is associated with approach-related motivation. The aim of this study was to examine the cerebellar asymmetry of motivational direction in approach-related behavior in the context of aggression. In this randomized double-blind sham-controlled crossover study, thirty healthy right-handed adult volunteers received 2mA active or sham left cathodal-right anodal transcranial direct current stimulation (tDCS) to the cerebellum on two separate occasions while engaging in the Point Subtraction Aggression Paradigm (PSAP) task to measure aggressive behavior. Self-reported state anger was assessed before, halfway and immediately after the task, and heart rate and heart rate variability (HRV) were measured during the task. No main effects of tDCS on aggressive behavior, heart rate and HRV were found. Higher state anger before and during the PSAP task was associated with increased aggressive behavior in the active compared to sham tDCS condition. Aggressive behavior was positively correlated with heart rate during active tDCS, while an inverse association was observed during sham tDCS. Results provide support for the cerebellar asymmetry of motivational direction in approach-related behavior and illustrate the importance of affective state-dependency in tDCS-related effects.

The cerebellum during provocation and aggressive behaviour: A 7 T fMRI study

Abstract Increasing empirical evidence points towards the involvement of the cerebellum in anger and aggressive behaviour. However, human functional neuroimaging studies so far have emphasised the involvement of subcortical and cortical regions, rather than examining the contributions of the cerebellum. In the present study, 7 T functional magnetic resonance imaging (fMRI) was used to assess cerebellar activation during provocation and aggressive behaviour elicited by the Point Subtraction Aggression Paradigm in 29 healthy adult volunteers. Provocations resulted in left posterior cerebellar activation, while right posterior cerebellar activation was associated with aggressive behaviour. Our findings confirm the involvement of distinct and lateralised non-motor related cerebellar areas during provocation and aggressive behaviour. This study adds to the growing recognition of the posterior cerebellar regions in emotion- and cognition-dedicated processes and to the role of the little brain in human aggression.

Contingencies for Aggression in the Point Subtraction Aggression Paradigm

Contingencies for Aggression in the Point Subtraction Aggression Paradigm

Evidence of the active participation of women in the intergroup conflict based on the use of aggression and cooperation

Intergroup conflict has been a persistent aspect of human societies since the emergence of our species. Various researchers have proposed that competition between groups has acted as a key selective force throughout human evolutionary history. Such intergroup competition for limited resources exacerbated the expression of intergroup aggression and intragroup cooperation. Furthermore, it would have a sexual dimorphism, with men demonstrating increased sensitivity to conflict threats—in order to maximize reproductive opportunities—, while women generally reject from active engagement in intergroup conflict. In the present study, we conducted behavioral experiments under controlled laboratory conditions to measure cooperation and aggression from using virtual games, specifically the Public Good Games and the Point Subtraction Aggression Paradigm, in a sample of 541 participants. We created control and experimental intergroup competition scenarios, where aggression and cooperation were necessary to increase monetary rewards. Our results shows that men modulate aggression and cooperation in the presence of intergroup conflict. In addition, our data also reveals that women cooperate more than men and display heightened levels of cooperation and aggression when confronted with intergroup conflict. These findings prompt a reevaluation of current functional theoretical models concerning the role of women in intergroup conflict and suggest that the dynamics of human aggression and cooperation may be more nuanced than previously believed.

Excluded and ashamed: Shame proneness interacts with social exclusion and testosterone reactivity to predict behavioral aggression

Exclusion from social relationships is a painful experience that may threaten an individual’s status and dominance. The steroid hormone testosterone, which fluctuates rapidly in response to such threats, may be implicated in subsequent behavioral action (e.g., aggressive or prosocial responses) that aims to protect or enhance one’s status after exclusion. Past research, however, indicates that the link between acute changes in testosterone and behavior depend on context-relevant individual dispositions. In the context of social exclusion, an individual’s level of shame proneness—characterized by a tendency to experience shame and to react submissively—is theoretically relevant to the testosterone-induced aggression relationship but has yet to be examined empirically. Here, men (n = 167) were randomly assigned to be socially included or excluded in the virtual ball-tossing game, Cyberball, after which aggressive behavior was examined using the Point Subtraction Aggression Paradigm (PSAP). Testosterone reactivity was measured via salivary hormone samples collected pre- and post-game. Moderated multiple regression analyses were run to examine the extent to which testosterone reactivity and shame proneness moderated the effect of Cyberball condition on aggression. Results revealed a significant two-way interaction between Cyberball condition and testosterone reactivity, as well as a three-way interaction including shame proneness. For individuals low in shame proneness, exclusion was associated with higher post-cyberball aggression among those who experienced a rise in testosterone but was associated with lower post-cyberball aggression among those who experienced a decrease in testosterone. For individuals high in shame proneness, however, exclusion did not meaningfully affect aggressive responses, regardless of whether they experienced an increase or decrease in testosterone. These findings extend our understanding of the moderating roles of context and disposition on the neuroendocrinology of aggression in social interaction

Investigating associations between appetite-regulating hormones, aggression and craving in males with cannabis use disorder

BackgroundAggression and craving are common and important withdrawal symptoms in cannabis use disorder. The present study investigated the association between appetite-regulating hormones, aggression, and craving during cannabis withdrawal syndrome (CWS). MethodsFifty-six male subjects diagnosed with cannabis withdrawal and 45 healthy males were included in the study. The Substance Craving Scale, the Buss–Perry Aggression Questionnaire, and the State-Trait Anxiety Inventory were implemented at baseline. Blood samples were drawn to measure ghrelin, leptin, adiponectin, and resistin levels in the serum. Then, the Point Subtraction Aggression Paradigm (PSAP) was applied. Bloodwork and psychometric assessment procedures were re-implemented after the PSAP. At the 7-day follow-up, psychometric assessments and hormone measurements were repeated in the CWS group. ResultsBaseline serum ghrelin and adiponectin levels were lower in the CWS group than controls at baseline. After PSAP, there was a significant increase in ghrelin levels of patients with CWS compared to controls. Patients yielded higher aggression scores, while there was no significant correlation between hormonal changes and PSAP findings. At 7-day follow, ghrelin and resistin levels significantly increased, while serum leptin decreased in patients with CWS. Finally, there was a positive association between craving and resistin levels. ConclusionsOur results present the changes in appetite-regulating hormones. Long-term follow-up studies are needed to shed light on neuroendocrinological aspects of cannabis withdrawal.

In vivo defensive behaviors, fear, and attention bias to physical and negative evaluation threats

Aggressive behavior is a major public health issue for which there are few efficacious treatments. Although much of information processing is automatic, there are few studies of early-stage decoding biases (e.g., attention bias to threat) and aggressive behavior, potentially resulting in missed opportunities for identifying targets of intervention. Previous studies are limited by indirect measures of attention bias and little consideration of proximal factors like state fear, which organizes perception and motivates defensive behaviors. We used laboratory methods (i.e., eye-tracking, idiographic mood induction, and the Point Subtraction Aggression Paradigm), to examine the association between attention bias to physical and negative evaluation threat and in vivo defensive responding (i.e., aggression and escape) and the potential moderating role of state fear among 74 undergraduate students. As predicted, attention bias to threat was positively associated with in vivo aggression. Fear did not potentiate aggression or modify the relationship between attentional bias to threat and aggression; however, in the fear condition, greater attentional bias to threat was associated with less escape behavior. Findings add to the sparse literature identifying early-stage decoding processes as possible risk factors of aggression and suggest a need for additional research on freeze behavior in response to threat and provocation.

Individual Differences in Frustrative Nonreward Behavior for Sucrose in Rats Predict Motivation for Fentanyl under Progressive Ratio.

Frustrative nonreward (FN) is a construct in the Negative Valence Systems domain of the Research Domain Criteria (RDoC) from the National Institute of Mental Health. An organism’s response to frustrating situations (e.g., inability to obtain an expected reward) has broad implications for a variety of neuropsychiatric conditions, including substance use disorders. The current project developed a first of its kind rat operant behavioral model of FN based loosely on the human Point Subtraction Aggression Paradigm (PSAP). The current study shows that individual differences in FN for sucrose pellets are consistent across sessions at baseline and that the task is sensitive to reward size in male rats. More importantly, high FN behavior for sucrose predicts early “breaking” for intravenous fentanyl self-administration under a progressive ratio (PR) schedule. These results solidify frustration/ FN as an important factor for substance use disorders in addition to craving, impulsivity, and habit.

Comparable level of aggression between patients with behavioural addiction and healthy subjects

Heightened aggression is identified in several psychiatric disorders, including addiction. In this preliminary study with a relatively small number of samples, aggression in subjects diagnosed with behavioural addiction (BA) was implicitly assessed using the point subtraction aggression paradigm (PSAP) test along with measurements of oxy- and deoxyhaemoglobin dynamics in the prefrontal cortex (PFC) during the test using functional near-infrared spectroscopy. Aggression in BA patients was no higher than that of healthy control (CT) subjects in the PSAP test. Although no apparent increase or decrease in haemoglobin concentrations was observed in the PFC of either BA patients or CT subjects, abnormal correlations within the PFC network were present in BA patients. Consistent with comparable aggression between the groups, blood concentrations of the sex hormone testosterone, which has been shown to be associated with aggressiveness, was even lower in BA patients than in CT subjects. In contrast, when a set of questionnaire surveys for the assessment of aggression were administered, BA patients rated themselves as more aggressive than non-BA subjects. Collectively, these results suggest that aggression may not be heightened in BA, but BA patients may overestimate their aggressiveness, raising concerns about the use of questionnaire surveys for assessments of affective traits such as aggression in behavioural addiction.

Transcranial Direct Current Stimulation Targeting the Ventromedial Prefrontal Cortex Reduces Reactive Aggression and Modulates Electrophysiological Responses in a Forensic Population

BackgroundStudies have shown that impairments in the ventromedial prefrontal cortex play a crucial role in violent behavior in forensic patients who also abuse cocaine and alcohol. Moreover, interventions that aimed to reduce violence risk in those patients are found not to be optimal. A promising intervention might be to modulate the ventromedial prefrontal cortex by high-definition (HD) transcranial direct current stimulation (tDCS). The current study aimed to examine HD-tDCS as an intervention to increase empathic abilities and reduce violent behavior in forensic substance dependent offenders. In addition, using electroencephalography, we examined the effects on the P3 and the late positive potential of the event-related potentials in reaction to situations that depict victims of aggression. MethodsFifty male forensic patients with a substance dependence were tested in a double-blind, placebo-controlled randomized study. The patients received HD-tDCS 2 times a day for 20 minutes for 5 consecutive days. Before and after the intervention, the patients completed self-reports and performed the Point Subtraction Aggression Paradigm, and electroencephalography was recorded while patients performed an empathy task. ResultsResults showed a decrease in aggressive responses on the Point Subtraction Aggression Paradigm and in self-reported reactive aggression in the active tDCS group. Additionally, we found a general increase in late positive potential amplitude after active tDCS. No effects on trait empathy and the P3 were found. ConclusionsCurrent findings are the first to find positive effects of HD-tDCS in reducing aggression and modulating electrophysiological responses in forensic patients, showing the potential of using tDCS as an intervention to reduce aggression in forensic mental health care.

Brain reactivity during aggressive response in women with premenstrual dysphoric disorder treated with a selective progesterone receptor modulator

Premenstrual dysphoric disorder (PMDD) is a psychiatric condition characterized by late luteal phase affective, cognitive, and physical impairment. The disorder causes significant suffering in about 5% of women in their reproductive age. Altered sensitivity of cognitive-affective brain circuits to progesterone and its downstream metabolite allopregnanolone is suggested to underlie PMDD symptomatology. Core mood symptoms include irritability and anger, with aggression being the behavioral outcome of these symptoms. The present study sought to investigate the neural correlates of reactive aggression during the premenstrual phase in women with PMDD, randomized to a selective progesterone receptor modulator (SPRM) or placebo. Self-reports on the Daily Record of Severity of Problems were used to assess PMDD symptoms and gonadal hormone levels were measured by liquid chromatography tandem mass spectrometry. Functional magnetic resonance imaging was performed in 30 women with PMDD, while performing the point subtraction aggression paradigm. Overall, a high SPRM treatment response rate was attained (93%), in comparison with placebo (53.3%). Women with PMDD randomized to SPRM treatment had enhanced brain reactivity in the dorsal anterior cingulate cortex and dorsomedial prefrontal cortex during the aggressive response condition. The fronto-cingulate reactivity during aggressive responses depended on treatment, with a negative relationship between brain reactivity and task-related aggressiveness found in the placebo but not the SPRM group. The findings contribute to define the role of progesterone in PMDD symptomatology, suggesting a beneficial effect of progesterone receptor antagonism, and consequent anovulation, on top-down emotion regulation, i.e., greater fronto-cingulate activity in response to provocation stimuli.

Using an Online Platform to Administer the Single-Session Point Subtraction Aggression Paradigm: An Initial Examination of Feasibility and Validity.

Online platforms represent a cost-effective option for data collection; however, it is unclear whether online administration of certain kinds of tasks (e.g., behavioral measures of aggression) poses validity threats. The present study provided a preliminary examination of effort (as indexed by total number of presses), differential drop-out, and believability of an online version of the single-session point subtraction aggression paradigm (PSAP). Two subsamples of participants were recruited; a sample recruited through Amazon's Mechanical Turk (n = 758) and an in-person undergraduate sample (n = 88). All participants completed the PSAP, along with measures of trait hostility and state anger. The online sample did not differ from the in-person sample on effort (i.e., total number of presses), and did not find the task less believable. Higher scores on state anger were associated with lower likelihood of beginning the online PSAP, but were not associated with prematurely closing the task. State anger was related to aggressive responding on the PSAP. Limitations of the online PSAP and considerations for future research are discussed.

Transcranial direct current stimulation (tDCS) as an intervention to improve empathic abilities and reduce violent behavior in forensic offenders: study protocol for a randomized controlled trial

BackgroundRecent studies show that changes in one of the brain areas related to empathic abilities (i.e. the ventromedial prefrontal cortex (vmPFC)) plays an important role in violent behavior in abusers of alcohol and cocaine. According to the models of James Blair, empathy is a potential inhibitor of violent behavior. Individuals with less empathic abilities may be less susceptible and motivated to inhibit violent behavior, which causes a higher risk of violence. Recent neuroscientific research shows that modulating (stimulation or inhibition) certain brain areas could be a promising new intervention for substance abuse and to reduce violent behavior, such as the neurostimulation technique transcranial direct current stimulation (tDCS). This study aims to investigate tDCS as an intervention to increase empathic abilities and reduce violent behavior in forensic substance use offenders.Methods/designA total sample of 50 male forensic substance abuse patients (25 active and 25 sham stimulation) will be tested in a double-blind placebo-controlled study, from which half of the patients will receive an active stimulation plus treatment as usual (TAU) and the other half will receive sham stimulation (placebo) plus TAU. The patients in the active condition will receive multichannel tDCS targeting the bilateral vmPFC two times a day for 20 min for five consecutive days. Before and after the stimulation period, the patients will complete self-report measurements, perform the Point Subtraction Aggression Paradigm (PSAP) and a passive viewing empathy task. Resting state electroencephalography (rsEEG) will be performed before and after the treatment period. A follow up will be conducted after 6 months. The primary outcome is to investigate multichannel tDCS as a new intervention to increase empathic abilities and reduce violent behavior in offenders with substance abuse problems. In addition, we will determine whether electrophysiological responses in the brain are affected by the tDCS intervention. Finally, the effects of tDCS on reducing craving will be investigated.DiscussionThis study is one of the first studies using multichannel tDCS targeting the vmPFC in a forensic sample. This study will explore the opportunities to introduce a new intervention to improve empathic abilities and reduce violence in forensic substance use offenders. Specifically, this study may give insight into how to implement the tDCS intervention in the setting of daily clinical practice in this complex, multiple-problem target group and with that contribute to reduction of recidivism.Trial registrationDutch Trial Register, NTR7701. Registered on 12 January 2019. Prospectively registered before the recruitment phase. https://www.trialregister.nl/trial/7459.Recruitment started on the 1st of February 2019 and will be finished approximately in the winter of 2019. Protocol version 1. 22 May 2019.

Frustrative Non-reward and Lab-Based Paradigms for Advancing the Study of Aggression in Persons with Psychosis

Prior research and assessment of aggression in schizophrenia and other psychotic conditions has focused on one or two levels of measurement (third-party observation and self-report) identified by the NIMH Research Domain Criteria (RDoC), while frequently neglecting a third (laboratory behavioral paradigms). We review aggression in psychosis using the RDoC conceptualization of frustrative non-reward; describe how lab-based behavioral paradigms, particularly, the Point Subtraction Aggression Paradigm (PSAP), can help to better understand aggression in individuals with psychosis; and suggest directions for future research. Many studies of violence in psychosis focus on field observations of behavior and self-report. However, laboratory behavioral paradigms such as the PSAP, which have not been widely adopted, hold conceptual promise for the study of aggression in schizophrenia. The RDoC represent a neurobehavioral approach for advancing behavioral health research that recommends multilevel investigations to include laboratory behavioral paradigms. The PSAP is one such behavioral measure with particular relevance to a frustrative non-reward conceptualization of aggression. The PSAP and its adaptations offer a promising methodology for future research of aggression in schizophrenia and other psychotic conditions. The method may likewise prove useful in individual cases, to enhance the incremental validity of violence risk assessment.

Intranasal administration of oxytocin decreases task-related aggressive responses in healthy young males

Aggression and distrust are often challenging problems in mental health treatment. Converging evidence reveals that oxytocin increases trust in social interactions and decreases fear of social betrayal. However, oxytocin has also been associated with protective behavior and, as such, might increase defensive aggressive reactions.In this randomized double-blind, placebo-controlled study, the effects of intranasal oxytocin (32IU) on task-related aggressive responses were measured using the Point Subtraction Aggression Paradigm (PSAP). Fifty-seven healthy males were enrolled and randomized to oxytocin (N = 30) or placebo (n = 27). Salivary oxytocin, cortisol and testosterone were measured serially prior to the intervention, and then before and after the PSAP, to evaluate the effects of oxytocin administration on hormonal functioning in relation to aggression. In addition, oxytocin was measured in urine collected directly after the experimental task, reflecting the 2 h period after oxytocin or placebo administration.The proportion of aggressive responses to the PSAP was significantly lower in participants receiving oxytocin versus placebo (β= -0.46, P = 0.01). No significant effect of oxytocin was found regarding defensive reactions. Urinary oxytocin was negatively associated with the proportion of aggressive responses to the PSAP in both the oxytocin and the placebo group (β= -0.02, P < 0.01), suggesting that higher levels of urinary oxytocin corresponded with reduced aggressive responding. Our results indicate that oxytocin administration reduces aggressive behavior in healthy young men. Moreover, increased endogenous urinary oxytocin is associated with less aggressive responding. Taken together, these findings suggest that oxytocin signaling has a causal influence on aggressive behavior.

The Impact of History of Aggression and Alcohol Use on Aggressive: Responding in the Laboratory

The current study examines how different levels of past aggression combined with self-reported levels of alcohol use impacted lab-based aggressive responding. Data were collected from 160 male undergraduate college students. Participants completed online measures of drinking (Alcohol Use Disorders Identification Test) and past aggression (Buss Perry Aggression Questionnaire) prior to a lab session assessing aggressive responding [Point Subtraction Aggression Paradigm (PSAP)]. Regression analyses revealed participants with “high” levels of past alcohol use and a history of “high” aggression were more likely to respond aggressively on the PSAP, a trend primarily driven by those with a history of physical aggression. For proactively aggressive participants, the risk for aggressive responding is greater in individuals with a history of physically aggressive behavior as they report higher alcohol use, relative to those “low” in past aggression. The interaction of alcohol use and past aggression was associated with continued aggressive behavior.

Sleep restriction alters reactive aggressive behavior and its relationship with sex hormones.

Few studies have experimentally manipulated sleep to study its effect on aggressive behavior. The current study examined how reactive aggression was affected by having sleep restricted to 4-hours on a single night, a level of disruption commonly experienced. Both rested and sleep-restricted participants completed the Point Subtraction Aggression Paradigm (PSAP), a laboratory task in which participants seek to earn points, are provoked by a fictitious opponent stealing their points, and may choose to steal points in response. Logistic mixed-effect models were used to investigate the effect of sleep restriction and the role of sex hormones on the odds of choosing to steal. For men, and women in the luteal phase of the menstrual cycle, sleep restriction did not result in significant changes reactive aggression, although the patterns of aggressive behavior appeared less reactive and retaliatory in nature. For women in the follicular phase of the menstrual cycle, sleep restriction was associated with higher levels of reactive aggression. For both men and women in the luteal phase, sleep restriction disrupted an association between hormone change over the task (testosterone and estradiol, respectively) and reactive aggression that was observed in their control participants. In addition, higher testosterone before the PSAP in men was associated with maintaining a high level of stealing over the task. These results indicate a complex dynamic in which sex hormones and sleep interact to predict aggressive behavior in response to provocation.

Force versus fury: Sex differences in the relationships among physical and psychological threat potential, the facial width-to-height ratio, and judgements of aggressiveness.

Individuals with larger facial width-to-height ratios (FWHRs) are judged as more threatening, and engage in more threat-related behavior, than do individuals with smaller FWHRs. Here we identified components of threat potential that are related to the FWHR. In Study 1, the FWHR was correlated positively with physical threat potential (bicep size) in women and with both physical and psychological (anger proneness) threat potential in men. Behavioral aggression was measured in a subset of these participants using the Point Subtraction Aggression Paradigm (costly aggression) and a Money Allocation Task (non-costly aggression). Psychological (but not physical) threat potential predicted non-costly aggression and physical (but not psychological) threat potential predicted costly aggression. In Study 2, a separate set of participants judged the anger proneness, strength, or aggressiveness of male participants photographed in Study 1. Participants' judgements of all three characteristics were associated with the FWHR, and there were sex differences in how aggressiveness was conceptualized (for women, aggressiveness was associated with anger proneness, for men, aggressiveness was associated with strength). These results are consistent with the hypothesis that the FWHR may be an adaptation to cue the threat potential of men.