Dark Tetrad personality traits, paraphilic interests, and the role of impulsivity: an EEG-study using a Go/No-Go paradigm.

Maladaptive personality traits, such as 'dark personalities' are found to result in a diverse set of negative outcomes, including paraphilic interests and associated (illegal) behaviors. It is however unclear how these are exactly related, and if related, if then only those individuals higher on dark personality traits and higher impulsivity engage in paraphilic behaviors. In the current study, 50 participants were recruited to investigate the relationship between Dark Tetrad personality traits (i.e., narcissism, psychopathy, Machiavellianism and everyday sadism), paraphilic interests (arousal and behavior) and the moderating role of impulsivity. Personality and paraphilic interests were investigated through self-report questionnaires. Impulsivity was measured both through self-reported dysfunctional impulsivity and the P3 event related potential using electroencephalography during the Go/No-Go task (i.e. response inhibition). The results showed that there was a positive association between psychopathy, sadism and paraphilic interests. Whereas everyday sadism was associated with paraphilic (self-reported) arousal, psychopathy was associated with paraphilic behavior. Although P3 amplitude was not associated with paraphilic interests, self-reported dysfunctional impulsivity was associated with paraphilic behavior specifically. However, there was no moderating role of dysfunctional impulsivity and response inhibition (P3) in the relationship between psychopathy and paraphilic behavior. Findings indicate that the relation between specific dark personalities and paraphilic interests may be more complex than initially thought. Nevertheless, risk assessment and intervention approaches for paraphilia and related behavior both may benefit from incorporating Dark Tetrad and impulsivity measurements.

Child Neuropsychological Functioning and Interpersonal Callousness as Predictors of Externalising Behaviour in Early Adolescence: A Prospective Population-based Study.

Externalizing problems are a key predictor of individual functioning in adulthood. Therefore, identifying possible risk factors for externalising problems is valuable for optimising prevention and treatment programmes. Previous research has shown that (domains of) neuropsychological functioning predict externalising problems later in life. However, the influence of callous traits, and sex as potential moderators in this relation remains unclear. The aim of this study was to examine associations between neuropsychological functioning in children (at age 8 years) and later externalising behaviour in adolescence (at age 14 years), as well as to test the role of callous traits (at age 10 years) and sex as moderating factors. The analyses were conducted using data from 661 Dutch children from the population-based Generation R Study (47.2% female). We found no association between neuropsychological functioning and later externalising behaviour. However, callous traits predicted externalising problems at age 14 years. Further, callous traits moderated the association between neuropsychological functioning and externalising behaviour, though this association dropped below the statistical significance level when adjusted for confounders. Specifically, while higher neuropsychological functioning was associated with more externalising behaviour in children with high callous traits, lower neuropsychological functioning was not associated with externalising behaviour in children with low callous traits. Although boys showed significantly higher externalising behaviours compared to girls, no moderating effect of sex was found on the association between neuropsychological functioning and externalising behaviour. These results add to a growing body of evidence supporting a distinct neurocognitive profile in children with high vs low callousness.

The effect of HD-tDCS on brain oscillations and frontal synchronicity during resting-state EEG in violent offenders with a substance dependence.

Violence is a major problem in our society and therefore research into the neural underpinnings of aggression has grown exponentially. Although in the past decade the biological underpinnings of aggressive behavior have been examined, research on neural oscillations in violent offenders during resting-state electroencephalography (rsEEG) remains scarce. In this study we aimed to investigate the effect of high-definition transcranial direct current stimulation (HD-tDCS) on frontal theta, alpha and beta frequency power, asymmetrical frontal activity, and frontal synchronicity in violent offenders. Fifty male violent forensic patients diagnosed with a substance dependence were included in a double-blind sham-controlled randomized study. The patients received 20 minutes of HD-tDCS two times a day on five consecutive days. Before and after the intervention, the patients underwent a rsEEG task. Results showed no effect of HD-tDCS on the power in the different frequency bands. Also, no increase in asymmetrical activity was found. However, we found increased synchronicity in frontal regions in the alpha and beta frequency bands indicating enhanced connectivity in frontal brain regions as a result of the HD-tDCS-intervention. This study has enhanced our understanding of the neural underpinnings of aggression and violence, pointing to the importance of alpha and beta frequency bands and their connectivity in frontal brain regions. Although future studies should further investigate the complex neural underpinnings of aggression in different populations and using whole-brain connectivity, it can be suggested with caution, that HD-tDCS could be an innovative method to regain frontal synchronicity in neurorehabilitation.

Sensation seeking and its relationship with psychopathic traits, impulsivity and aggression: a validation of the Dutch Brief Sensation Seeking Scale (BSSS).

Sensation seeking is a personality trait that manifests as a preference for change, variety and novelty. Sensation seeking has been positively associated with different externalising behaviours. However, its associations with psychopathic traits, impulsivity and aggression are unclear. These associations were examined via the psychometric properties of the Dutch version of the Brief Sensation Seeking Scale (BSSS) using individuals from the general population and forensic patients. The results show that the BSSS has good psychometric properties, including test-retest reliability and a four-factor structure. Additionally, the results support associations between sensation seeking and psychopathic traits, impulsivity and total scores of aggression but revealed no specific associations with different types of aggression (e.g. proactive and reactive). The Dutch BSSS is a valuable tool for assessing sensation seeking in both the general population and forensic patients. Future research should further examine its utility and explore the role of sensation seeking in antisocial conduct.

Neurobiological Responses towards Stimuli Depicting Aggressive Interactions in Delinquent Young Adults and Controls: No Relation to Reactive and Proactive Aggression.

Neurobiological measures underlying aggressive behavior have gained attention due to their potential to inform risk assessment and treatment interventions. Aberrations in responsivity of the autonomic nervous system and electrophysiological responses to arousal-inducing stimuli have been related to emotional dysregulation and aggressive behavior. However, studies have often been performed in community samples, using tasks that induce arousal but not specifically depict aggression. In this study, we examined differences in psychophysiological (i.e., heart rate, respiratory sinus arrhythmia, skin conductance level) and electrophysiological responses (i.e., P3, late positive potential, mu suppression) to aggressive versus neutral scenes in a sample of 118 delinquent young adults and 25 controls (all male, aged 18-27). With respect to group differences, we only found significant higher SCL reactivity during the task in the delinquent group compared to controls, but this was irrespective of condition (aggressive and neutral interactions). Within the delinquent group, we also examined associations between the neurobiological measures and reactive and proactive aggression. No significant associations were found. Therefore, although we found some indication of emotional dysregulation in these delinquent young adults, future studies should further elucidate the neurobiological mechanisms underlying emotional dysregulation in relation to different types of aggression.

Cross-cultural Validity of the Reactive-Proactive Aggression Questionnaire Among Adults Across Five Countries.

This study aims to test psychometric properties and factor invariance of the Reactive-Proactive Aggression Questionnaire (RPQ) for adults across five countries: Serbia (N = 409), Mauritius (N = 400), the United States (N = 389), the Netherlands (N = 372), and China (N = 325). The results supported the two-factor structure across country samples, with a marginal model fit in Mauritius. Results also supported the congruent factor structure of Reactive Aggression scale across countries, while the Proactive Aggression scale can be considered as equal across samples from Serbia, the United States, and China, but not from Mauritius and the Netherland. Among items from the Proactive Aggression scale, those referring to open aggression aimed at obtaining social status and dominance, frightening or harming others, obtained the highest loadings across all samples and could be considered as the good representatives of adult proactive aggression. This is the first study in which cross-cultural validation of the RPQ among adults has been tested and results suggested that there are some cultural differences in expression of proactive aggression.

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

BACKGROUND: Studies 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. METHODS: Fifty 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. RESULTS: Results 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. CONCLUSIONS: Current 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.

Modulation of control: Can HD-tDCS targeting the dACC reduce impulsivity?

BACKGROUND: The dorsal anterior cingulate cortex (dACC) and its neurocircuits are central in impulsivity, and maladaptive dACC activity has been implicated in psychological disorders characterized by high trait impulsivity. High-Definition transcranial Direct Current Stimulation (HD-tDCS) is a non-invasive neuromodulation tool that, with certain electrode configurations, can be optimized for targeting deeper subcorticalbrainstructures, such as the dACC. OBJECTIVES: Using behavioural and electrophysiological measures we investigated whether HD-tDCS targeting the dACC could modulate two key components of impulsivity, inhibitory control and error processing. METHODS: Twenty-three healthy adults with high trait impulsivity participated in two experimental sessions. Participants received active or sham HD-tDCS in counterbalanced order with a wash-out period of at least 3 days, as part of a single-blind, cross-over design. EEG was recorded during the Go-NoGo task before, directly after, and 30 min after HD-tDCS. RESULTS: HD-tDCS targeting the dACC did not affect inhibitory control performance on the Go-NoGo task, but there was evidence for a delayed change in underlying neurophysiological components of motor inhibition (NoGo P3) and error processing (error related negativity; ERN) after one session of HD-tDCS. CONCLUSION: HD-tDCS has potential to modulate underlying neurophysiological components of impulsivity. Future studies should further explore to what degree the dACC was affected and whether multi-session HD-tDCS has the capacity to also induce behavioural changes, particularly in clinical samples characterized by high trait impulsivity.

Triarchic or septarchic?-Uncovering the Triarchic Psychopathy Measure's (TriPM) structure.

The Triarchic Psychopathy Measure (TriPM) is based on a 3-dimensional conceptual model, though few studies have directly tested a 3-factor structure. The current study used a large community sample (N = 1,064, 53% males, Mage = 34) to test the structure of the TriPM via exploratory and confirmatory factor analysis, along with 4 community replication samples from North American and Europe (Ns = 511-603, 33-49% males) and 1 European male offender sample (N = 150). Three of these samples were also used to model the correlations between relevant external correlates and the original TriPM factors versus emergent factors to examine the cost of misspecifying TriPM structure. The model analyses did not support a 3-factor model (comparative fit index = .76, root mean square error of approximation = .08), revealing a number of items with limited statistical information, but uncovered a 7-factor structure (comparative fit index = .92, root mean square error of approximation = .04). From the majority of Boldness, Meanness, and Disinhibition scale items, respectively, emerged 3 factors reflecting Positive Self-Image, Leadership, and Stress Immunity; 2 factors tapping Callousness and Enjoy Hurting; and 2 factors involving Trait Impulsivity and Overt Antisociality. Further, the Enjoy Hurting and Overt Antisociality factors were more strongly correlated with one another than with the other scales from their home domains (Callousness and Impulsivity). All 7 emergent factors were differentially associated with the external correlates, suggesting that the 3 original TriPM factors do not optimally represent the conceptual model underlying the TriPM. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

The perils of untested assumptions in theory testing: A reply to Patrick et al. (2020).

We respond to a critique by Patrick et al. (2020) of our recent study (Roy et al., 2020) that raised questions regarding the three-factor model of the Triarchic Psychopathy Measure (TriPM). Roy et al. demonstrated that a replicable model involving seven unidimensional factors accounted for the TriPM items across North American and European general population samples, as well as European male offenders. Despite having access to large TriPM datasets, the Patrick et al. critique relied on tangential analyses of general personality traits, using a single college sample with TriPM data as supplemental. Thus, Patrick et al. ignored findings highlighting multidimensional TriPM scales and the uncertainty they introduce with respect to the larger nomological network of psychopathy. In our reply, we demonstrate additional problems with the three-factor TriPM model and show that the seven-factor model out-performs the three-factor model in predicting correlates of psychopathy. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

The Empathic Brain of Psychopaths: From Social Science to Neuroscience in Empathy.

Empathy is a crucial human ability, because of its importance to prosocial behavior, and for moral development. A deficit in empathic abilities, especially affective empathy, is thought to play an important role in psychopathic personality. Empathic abilities have traditionally been studied within the social and behavioral sciences using behavioral methods, but recent work in neuroscience has begun to elucidate the neural underpinnings of empathic processing in relation to psychopathy. In this review, current knowledge in the social neuroscience of empathy is discussed and a comprehensive view of the neuronal mechanisms that underlie empathy in psychopathic personality is provided. Furthermore, it will be argued that using classification based on overt behavior, we risk failing to identify important mechanisms involved in the psychopathology of psychopathy. In the last decade, there is a growing attention in combining knowledge from (neuro)biological research areas with psychology and psychiatry, to form a new basis for categorizing individuals. Recently, a converging framework has been put forward that applies such approach to antisocial individuals, including psychopathy. In this bio-cognitive approach, it is suggested to use information from different levels, to form latent categories on which individuals are grouped, that may better reflect underlying (neurobiological) dysfunctions. Subsequently, these newly defined latent categories may be more effective in guiding interventions and treatment. In conclusion, in my view, the future understanding of the social brain of psychopaths lies in studying the complex networks in the brain in combination with the use of other levels of information (e.g., genetics and cognition). Based on that, profiles of individuals can be formed that can be used to guide neurophysiological informed personalized treatment interventions that ultimately reduce violent transgressions in individuals with psychopathic traits.

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.

BACKGROUND: Recent 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/DESIGN: A 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. DISCUSSION: This 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 REGISTRATION: Dutch 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.

Electrophysiological correlates of empathic processing and its relation to psychopathic meanness.

OBJECTIVE: A lack of empathy and the presence of predatory tendencies are considered key features of psychopathic meanness. Previous electrophysiological studies on empathy in relation to psychopathic traits have focused mainly on empathy for pain; therefore, little is known about the electrophysiological correlates of empathy in aggressive situations that are particularly relevant for psychopathic meanness. METHOD: We employed electroencephalography in a community sample (n = 70), the majority of whom had attained a higher level of education. All participants were screened for not having psychiatric conditions or criminal history. The P3 and late positive potential (LPP) event-related potentials and mu rhythm suppression were examined as indices of empathic processing during the observation of situations in which victims of aggression were depicted. RESULTS: As predicted, it was found that persons with elevated levels of psychopathic meanness scored lower on trait empathy and assigned higher positive valence to the aggression scenes. It is interesting that those scoring higher on meanness also scored higher on empathy for the perpetrator. In addition, it was found that psychopathic meanness was negatively related to LPP amplitudes following pictures of aggressive situations. No significant associations were found between meanness and the P3 or between meanness and mu suppression. CONCLUSIONS: This study was the first to assess the electrophysiological signature of empathy during the processing of pictures depicting aggressive situations and the relationships with psychopathic meanness. The outcomes highlight the need for more integrative approaches to further study the complex pattern of relationships between empathy and psychopathic meanness. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Examination of the Triarchic Assessment Procedure for Inconsistent Responding in six non-English language samples.

The Triarchic Assessment Procedure for Inconsistent Responding (TAPIR; Mowle et al., 2016) was recently developed to identify inattentiveness or comprehension difficulties that may compromise the validity of responses on the Triarchic Psychopathy Measure (TriPM; Patrick, 2010). The TAPIR initially was constructed and cross-validated using exclusively English-speaking participants from the United States; however, research using the TriPM has been increasingly conducted internationally, with numerous foreign language translations of the measure emerging. The present study examined the cross-language utility of the TAPIR in German, Dutch, Swedish, and Italian translations of the TriPM using 6 archival samples of community members, university students, forensic psychiatric inpatients, forensic detainees, and adolescents residing outside the United States (combined N = 5,404). Findings suggest that the TAPIR effectively detects careless responding across these 4 translated versions of the TriPM without the need for language-specific modifications. The TAPIR total score meaningfully discriminated genuine participant responses from both fully and partially randomly generated data in every sample, and demonstrated further utility in detecting fixed "all true" or "all false" response patterns. In addition, TAPIR scores were reliably associated with inconsistent responding scores from another psychopathy inventory. Specificity for a range of tentative cut scores for assessing profile validity was modestly reduced among our samples relative to rates previously obtained with the English version of the TriPM; however, overall the TAPIR appears to demonstrate satisfactory cross-language generalizability. (PsycINFO Database Record

Further Evidence for Reliability and Validity of the Triarchic Psychopathy Measure in a Forensic Sample and a Community Sample.

Psychopathy is often described as a constellation of personality characteristics encompassing features such as impulsivity and antisociality, and a lack of empathy and guilt. Although the use of self-reports to assess psychopathy is still debated, there are distinct advantages to such measures and recent research suggests that they may not be as problematic as previously thought. This study further examined the reliability and validity of the Triarchic Psychopathy Measure (TriPM) in a community sample (N = 496) and forensic psychiatric patient sample (N = 217). Results indicated excellent internal consistencies. Additionally, the TriPM total and subscale scores related as expected to different subscales of the Psychopathic Personality Inventory -Revised (PPI-R) and to the Reactive and Proactive Aggression Questionnaire, reflecting good construct validity. Most importantly, ROC curve analyses showed that the TriPM evidenced better discrimination between the community sample and forensic psychiatric patients than the PPI-R. The current study extends the existent evidence demonstrating that the TriPM can be used as an efficient self-report instrument.

Positive symptoms, substance use, and psychopathic traits as predictors of aggression in persons with a schizophrenia disorder.

It is still not clear what the unique contribution of particular psychopathological factors is in explaining aggression in schizophrenia. The current study examined whether persecutory ideations, psychopathy and substance use are associated with different measures of aggressive behavior. We expected that persecutory ideations are associated with reactive aggression, and psychopathic traits are more associated with proactive aggression of inpatients. 59 inpatients with schizophrenia were included. Persecutory ideations we assessed using the Persecutory Ideation Questionnaire (PIQ), psychopathic traits with the revised version of Psychopathic Personality Inventory (PPI-R) and substance use was assessed using the Comprehensive Assessment of Symptoms and History (CASH). In addition, aggression was measured with the Reactive and Proactive Aggression Questionnaire (RPQ), in an experimental task using the Point Subtraction Aggression Paradigm (PSAP) and on the ward using the Social Dysfunction and Aggression Scale (SDAS). Results showed that psychopathy explains most of the variance in self-reported proactive and reactive aggression. In contrast, persecutory ideations explain most of the variance in observed aggression on the ward. Results implicate that it is important to acknowledge comorbid factors in patients with schizophrenia for more precise risk assessment and appropriate treatment for aggressive patients with schizophrenia.

Brain activity elicited by reward and reward omission in individuals with psychopathic traits: An ERP study.

Psychopathy has been associated with behavioral adaptation deficits, which might be associated with problems in feedback and reward processing. In the present study, we examined the relation between psychopathic traits and reward processing in a passive gambling task. A total of 39 male participants who scored high (HP) and 39 male participants who scored low (LP) on the Triarchic Psychopathy Measure (TriPM), total score were tested. Feedback-related Event-Related Potentials (ERPs; i.e., P2, FRN, and P3) on predicted and unpredicted rewards and reward omissions were compared between both groups. It was found that in HP individuals, the P2 was enhanced for predicted rewards and reward omissions, but not for unpredicted stimuli. Moreover, HP individuals as compared to the LP individuals demonstrated a generally reduced P3 amplitude. The FRN amplitude, however, did not differ between the two groups. In addition, HP individuals showed enhanced reward sensitivity on the self-report level. Taken together, these findings suggest that HP individuals show enhanced sensitivity to early and reduced sensitivity to later markers of processing reinforcement learning signals, which points in the direction of compromised behavioral adaptation.

Anti-social personality characteristics and psychotic symptoms: Two pathways associated with offending in schizophrenia.

BACKGROUND: Several research groups have shown that people with schizophrenia who offend do not form a homogenous group. A three-group model claimed by Hodgins proposes distinguishing between people who start offending before the onset of psychosis (early starters), after psychosis onset but at age 34 years or under (late starters) and after psychosis onset but at age 35 years or older (late first offenders). AIMS: This study aimed to test the hypotheses (1) that the personality of early starters and non-psychotic offenders would be similar, but different from either late-starter group; (2) that the late-starter groups would be more likely to have positive psychotic symptoms than non-criminal patients with schizophrenia; and (3) that symptom types would differentiate the psychotic groups. METHODS: A retrospective file study was conducted on cases of 97 early starters, 100 late starters and 26 late first offenders all drawn from the Netherlands Institute of Forensic Psychiatry and Psychology (NIFP) archives 1993-2008, 115 non-psychotic offenders from 2005-2008 NIFP archives and 129 patients with schizophrenia and no criminal history from one general service in Rotterdam. RESULTS: Early starters closely resembled the non-psychotic offenders in their premorbid anti-social personality characteristics. The two late-onset offending psychosis groups were more likely to have persecutory and/or grandiose delusions than non-offenders with psychosis, but so were the early starters. IMPLICATIONS: In a first study to compare subgroups of offenders with psychosis directly with non-psychotic offenders and non-offenders with psychosis, we found such additional support for a distinction between early and late starters with psychosis that different treatment strategies would seem indicated, focusing on personality and substance misuse for the former but psychotic symptoms for all. It remains to be seen whether the higher rate of alcohol misuse amongst late first offenders is a fundamental distinction or a function of age difference.

The role of ideational distress in the relation between persecutory ideations and reactive aggression.

BACKGROUND: People with schizophrenia are more likely to be violent than the people without it. Feeling driven to act on persecutory delusions may be one explanation for this, but it remains unclear why some should act on such delusions but some not. Acquisition of data from people who are very ill is problematic. Our study explores testing of hypotheses on similar ideational and behavioural associations among healthy recruits from the general population. AIMS: This study aims to test the effect of distress induced by persecutory ideas on any relationships between those ideas and aggressive behaviour, and the effect of gender. METHODS: Twenty-four men and 53 women from the general population participated in this study. The measures of aggressive behaviour were experimentally induced aggressive responding, self-reported aggressive behaviour in general, and self-reported reactive and proactive aggressive behaviours. RESULTS: Among men, persecutory ideation predicted reactive aggressive responding and aggressive style of behaviour only in those who experienced higher levels of persecutory ideational distress. Among women, with generally lower levels of aggression, the role of ideational distress was more complicated; Women in the low distress group responded with higher aggression on the task. Women in the higher distress group responded with higher aggressive style. For neither men nor women were there links between persecutory ideation and proactive aggression, regardless of distress. CONCLUSIONS: Ideational distress moderates the relation between persecutory ideation and aggression in different measures of aggression in men and women. IMPLICATIONS FOR PRACTICE AND/OR RESEARCH: Recognition of a relation between persecutory ideations and aggression is also important in the general population. Insight in the theory of acting upon delusions may lead to more accurate violence risk assessment. Facilitation of early detection of experienced delusional distress may lead to development of more specific psychotherapeutic interventions to manage violence risk.