Characterizing aggressive behavior in a forensic population

Brain Anatomy in Boys with Conduct Disorder: Differences Among Aggression Subtypes

Aggression is a core feature of conduct disorder (CD), but the motivation, execution of aggression may vary. A deeper understanding of the neural substrates of aggressive behaviours is critical for effective clinical intervention. Seventy-six Boys with CD (50 with impulsive aggression (I-CD) and 26 with premeditated aggression (P-CD)) and 69 healthy controls (HCs) underwent a structural MRI scan and behavioural assessments. Whole-brain analyses revealed that, compared to HCs, the I-CD group showed significant cortical thinning in the right frontal cortex, while the P-CD group demonstrated significant folding deficits in the bilateral superior parietal cortex. Both types of aggression negatively correlated with the left amygdala volume, albeit in different ways. The present results demonstrated that the complex nature of aggression relies on differentiated anatomical substrates, highlighting the importance of exploring differential circuit-targeted interventions for CD patients.

Virtual Reality for Aggression Assessment: The Development and Preliminary Results of Two Virtual Reality Tasks to Assess Reactive and Proactive Aggression in Males

Validly measuring aggression is challenging because self-reports are plagued with biased answer tendencies and behavioral measures with ethical concerns and low ecological validity. The current study, therefore, introduces a novel virtual reality (VR) aggression assessment tool, differentially assessing reactive and proactive aggression. Two VR tasks were developed, one in an alley environment (N = 24, all male, Mage = 23.88, 83.3% students) and an improved second one in a bar (N = 50, all male, Mage = 22.54, 90% students). In this bar VR task, participants were randomly assigned to either the reactive condition where they were triggered by a cheating and insulting dart-player or to the proactive condition where they could earn extra money by aggressing. Participants' level of self-reported aggression and psychopathy was assessed, after which they engaged in either the reactive or proactive VR task. Changes in affect and blood pressure were also measured. Aggression in the reactive VR task was evidenced to mostly display convergent validity because it positively correlated with self-reported aggression and total and fearless dominance factor scores of psychopathy, and there was a trend relationship with increased systolic blood pressure. The validity of the proactive aggression variant of our VR bar paradigm received less support, and needs more refinement. It can be concluded that VR is a potentially promising tool to experimentally induce and assess (reactive) aggression, which has the potential to provide aggression researchers and clinicians with a realistic and modifiable aggression assessment environment.

Parsing Associations Between Dimensions of Empathy and Reactive and Proactive Aggression

The broad dimension of empathy has been shown to underlie various forms of psychopathology, most extensively studied for the externalizing spectrum of psychopathology. However, associations between subdimensions of empathy and functions of aggression remain unclear. The current study (N = 409) aimed to investigate common and specific associations between a higher-order model of aggression, comprising reactive aggression (RA) and proactive aggression (PA) factors with an overarching general aggression factor, and item-level factor analytically derived dimensions of empathy: affective/self-oriented empathy and cognitive/other-oriented empathy. Results demonstrated specific and opposing associations between dimensions of empathy and the general aggression factor, such that affective/self-oriented empathy was positively associated, and cognitive/other-oriented empathy was negatively associated with general aggression. Affective/self-oriented empathy was positively associated with RA, whereas cognitive/other-oriented empathy was negatively associated with RA and PA. Results confirm the importance of considering the multidimensionality of empathy and aggression and suggest both common and distinct pathways from empathy to aggression.

Nurse-led mind-body relaxation intervention in prison: A multiperspective mixed-method evaluation

BACKGROUND

Mind-body relaxation techniques are complementary or alternative to medication to manage high stress and anxiety levels in prisons.

PURPOSE

To assess the motivation to attend and perceived benefits of a nurse-led group relaxation intervention in prison, investigate the experience of participants, prison officers, and health professionals, and identify improvements.

METHOD

Exploratory study was conducted in a post-trial facility in Switzerland using a multiperspective convergent parallel mixed method drawing from participatory action research principles.

FINDINGS

Reasons for attendance included back problems, mental tension, physical fitness, relaxation, and sleep problems. Perceived benefits comprised autonomy in self-practice, decreased physical tensions and anxiety, and improvement of sleep and physical fitness. Qualitative findings converged highlighting the importance of body-centering, relaxation as an alternative to medication, negative representations about relaxation sessions (useless, effeminate), and recommendations for improvement, including audio-visual support for self-practice.

DISCUSSION

Long-standing mind-body relaxation interventions led by nurses in groups may offer participants a beneficial and operationally feasible complement to stress management in prisons.

Are Owls and Larks Different When it Comes to Aggression? Genetics, Neurobiology, and Behavior

This review focuses on the contribution of circadian rhythms to aggression with a multifaceted approach incorporating genetics, neural networks, and behavior. We explore the hypothesis that chronic circadian misalignment is contributing to increased aggression. Genes involved in both circadian rhythms and aggression are discussed as a possible mechanism for increased aggression that might be elicited by circadian misalignment. We then discuss the neural networks underlying aggression and how dysregulation in the interaction of these networks evoked by circadian rhythm misalignment could contribute to aggression. The last section of this review will present recent human correlational data demonstrating the association between chronotype and/or circadian misalignment with aggression. With circadian rhythms and aggression being a burgeoning area of study, we hope that this review initiates more interest in this promising and topical area.

Developing Attributes and Attribute-Levels for a Discrete-Choice Experiment: An Example for Interventions of Impulsive Violent Offenders

BACKGROUND

Discrete-Choice Experiments (DCEs) are used to assess the strength of preferences and value of interventions, but researchers using the method have been criticised for failing to either undertake or publish the rigorous research for selecting the necessary attributes and levels. The aim of this study was to elicit attributes to inform a DCE to assess societal and offenders' preferences for, and value of, treatment of impulsive-violent offenders. In doing so, this paper thoroughly describes the process and methods used in developing the DCE attributes and levels.

METHODS

Four techniques were used to derive the final list of attributes and levels: (1) a narrative literature review to derive conceptual attributes; (2) seven focus group discussions (FGDs) comprising 25 participants including offenders and the general public and one in-depth interview with an offender's family member to generate contextual attributes; (3) priority-setting methods of voting and ranking to indicate participants' attributes of preference; (4) a Delphi method consensus exercise with 13 experts from the justice health space to generate the final list of attributes.

RESULTS

Following the literature review and qualitative data collection, 23 attributes were refined to eight using the Delphi method. These were: treatment effectiveness, location and continuity of treatment, treatment type, treatment provider, voluntary participation, flexibility of appointments, treatment of co-morbidities and cost.

CONCLUSION

Society and offenders identified similar characteristics of treatment programs as being important. The mixed methods approach described in this manuscript contributes to the existing limited methodological literature in DCE attribute development.

Psychometric properties of the Impulsive/Premeditated Aggression Scale in Portuguese community and forensic samples

Abstract Introduction Aggression can be defined according to impulsive or premeditated features. Impulsivity is defined as an uncontrolled and unplanned form of aggression. On the contrary, premeditation requires planning and is goal-oriented. Objective The purpose of this study was to validate the basic psychometric properties of the Impulsive/Premeditated Aggression Scale (IPAS) into European Portuguese. The scale evaluates aggression according to impulsive and premeditated features, which are considered the predominant forms of aggressive behavior, and can be used in community, forensic and clinical settings. Methods Participants from a community sample (n = 957; 424 male) and incarcerated individuals (n = 115, all male) completed the IPAS. Results Internal consistency and reliability indicated that the scale has good psychometric properties in both samples. Data from a principal component analysis (PCA) demonstrated similarities to previous structures reported in the literature. Conclusions The scale demonstrated to be sensitive to the bimodal classification of aggression in community and forensic samples, indicating its utility in the characterization of aggressive patterns.

Assessing societal and offender perspectives on the value of offender healthcare: a stated preference research protocol

INTRODUCTION

The increasing burden that offenders place on justice and health budgets necessitates better methods to determine the benefits of and value society places on offender programmes to guide policy regarding resource allocation. The aim of this paper is to demonstrate how economic methods will be used to determine the strength of preferences and value of violent offender treatment programmes from the perspectives of offenders, their families and the general population.

METHODS AND ANALYSIS

Two stated preference economic methods, discrete choice experiment (DCE) and contingent valuation (CV), will be used to assess society's and offenders' value of treatment programmes. The mixed methods process involves a literature review and qualitative methods to derive attributes and levels for the DCE and payment card values for the CV. Consensus building approaches of voting, ranking and the Delphi method will be used to further refine the findings from the qualitative phase. Attributes and their levels will be used in a D-efficient Bayesian experimental design to derive choice scenarios for the development of a questionnaire that will also include CV questions. Finally, quantitative surveys to assess societal preferences and value in terms of willingness to pay will be conducted.

ETHICS AND DISSEMINATION

Ethics approval for this study was obtained from the University of New South Wales (UNSW) Human Research Ethics Committee, Corrective Services New South Wales Ethics Committee and the Aboriginal Health and Medical Research Council ethics committee. The findings will be made available on the Kirby Institute UNSW website, published in peer-reviewed journals and presented at national and international conferences.

A preliminary investigation of impulsivity, aggression and white matter in patients with bipolar disorder and a suicide attempt history

BACKGROUND

Impulsivity and aggression may be associated with suicide attempts in bipolar disorder (BD), but findings have been inconsistent. Abnormalities in anterior white matter tracts that project to the frontal lobes mediate top-down regulation of emotion and may contribute to this clinical phenomenology.

METHODS

We assessed white matter (i.e., fractional anisotropy) in anterior and posterior brain regions using diffusion tensor imaging in 18 patients with BD and no prior suicide attempt (BD-S), 12 patients with BD and a prior suicide attempt (BD+S), and 12 healthy volunteers. Patients completed the Urgency, Premeditation, Perseverance, Sensation Seeking, Positive Urgency (UPPS-P) Impulsive Behavior Scale and Impulsive Premeditated Aggression Scale (IPAS). All individuals completed the Barratt Impulsiveness Scale (BIS-11).

RESULTS

Patients with BD+S had higher overall impulsivity (assessed using both the UPPS-P Impulsive Behavior Scale and BIS-11) and premeditated aggression compared to patients with BD-S. There were no significant group differences on measures of fractional anisotropy (FA). In patients with BD+S, however, higher FA in the anterior (but not the posterior) brain regions correlated with greater overall impulsivity on the UPPS-P Impulsive Behavior Scale. There were no significant correlations between either anterior or posterior brain regions with clinical measures in patients with BD-S.

LIMITATIONS

Cross-sectional study, sample size and possible contribution of psychotropic medications.

CONCLUSION

Impulsivity and aggression may be risk factors for a suicide attempt in BD. White matter in the anterior limb of the internal capsule and anterior corona radiata may play a role in this phenomenology.

The Operational Development and Empirical Testing of the Terrorist Radicalization Assessment Protocol (TRAP-18)

The Terrorist Radicalization Assessment Protocol (TRAP-18) is a structured professional judgment instrument for threat assessment of the individual terrorist. It is a rationally derived theoretical model comprising eight proximal warning behaviors and 10 distal characteristics. Empirical research on the TRAP-18 is reviewed, including both nomothetic and idiographic studies of individual terrorists in both the United States and Europe. Mean interrater reliability is 0.895 (Cohen's kappa), ranging from 0.69 to 1.0. Evidence of criterion validity has been demonstrated, including usefulness of the instrument across various extremist ideologies (jihadism, ethnic nationalism, and single-issue), and its ability to discriminate between thwarted and successful attackers. The instrument appears to advance the domain recommendations of Monahan (2012, 2016) for the risk assessment of the individual terrorist. The TRAP-18 is further discussed as a threat assessment instrument for mental health clinicians. The limitations of the current research provide direction for further studies to assess its reliability and construct, discriminant, and predictive validity.

Two types of aggression in human evolution

Two major types of aggression, proactive and reactive, are associated with contrasting expression, eliciting factors, neural pathways, development, and function. The distinction is useful for understanding the nature and evolution of human aggression. Compared with many primates, humans have a high propensity for proactive aggression, a trait shared with chimpanzees but not bonobos. By contrast, humans have a low propensity for reactive aggression compared with chimpanzees, and in this respect humans are more bonobo-like. The bimodal classification of human aggression helps solve two important puzzles. First, a long-standing debate about the significance of aggression in human nature is misconceived, because both positions are partly correct. The Hobbes-Huxley position rightly recognizes the high potential for proactive violence, while the Rousseau-Kropotkin position correctly notes the low frequency of reactive aggression. Second, the occurrence of two major types of human aggression solves the execution paradox, concerned with the hypothesized effects of capital punishment on self-domestication in the Pleistocene. The puzzle is that the propensity for aggressive behavior was supposedly reduced as a result of being selected against by capital punishment, but capital punishment is itself an aggressive behavior. Since the aggression used by executioners is proactive, the execution paradox is solved to the extent that the aggressive behavior of which victims were accused was frequently reactive, as has been reported. Both types of killing are important in humans, although proactive killing appears to be typically more frequent in war. The biology of proactive aggression is less well known and merits increased attention.

Validation of the Portuguese Version of Impulsive-Premeditated Aggression Scale in an Inmate Population

Aggression is one of the core symptoms of antisocial personality disorder (ASPD) with therapeutic and prognostic relevance. ASPD is highly prevalent among inmates, being responsible for adverse events and elevated direct and indirect economic costs for the criminal justice system. The Impulsive/Premeditated Aggression Scale (IPAS) is a self-report instrument that characterizes aggression as either predominately impulsive or premeditated. This study aims to determine the validity and reliability of the IPAS in a sample of Portuguese inmates. A total of 240 inmates were included in the study. A principal component factor analysis was performed so as to obtain the construct validity of the IPAS impulsive aggression (IA) and premeditated aggression (PM) subscales; internal consistency was determined by Cronbach's alpha coefficient; convergent and divergent validity of the subscales were determined analyzing correlations with the Barratt Impulsiveness scale, 11th version (BIS-11), and the Psychopathic Checklist Revised (PCL-R). The rotated matrix with two factors accounted for 49.9% of total variance. IA subscale had 11 items and PM subscale had 10 items. The IA and PM subscales had a good Cronbach's alpha values of 0.89 and 0.88, respectively. The IA subscale is correlated with BIS-11 attentional, motor, and non-planning impulsiveness dimensions (p < 0.05). The PM subscale is correlated with BIS-11 attentional, motor impulsiveness dimensions (p < 0.05). The PM subscale is correlated with PCL-R interpersonal, lifestyle, and antisocial dimensions (p < 0.05). The IA subscale is not correlated with PCL-R. The Portuguese translated version of IPAS has adequate psychometric properties, allowing the measurement of impulsive and premeditated dimensions of aggression.

Are Proactive and Reactive Aggression Meaningful Distinctions in Adolescents? A Variable- and Person-Based Approach

This study was designed to examine whether proactive and reactive aggression are meaningful distinctions at the variable- and person-based level, and to determine their associated behavioral profiles. Data from 587 adolescents (mean age 15.6; 71.6 % male) from clinical samples of four different sites with differing levels of aggression problems were analyzed. A multi-level Latent Class Analysis (LCA) was conducted to identify classes of individuals (person-based) with similar aggression profiles based on factor scores (variable-based) of the Reactive Proactive Questionnaire (RPQ) scored by self-report. Associations were examined between aggression factors and classes, and externalizing and internalizing problem behavior scales by parent report (CBCL) and self-report (YSR). Factor-analyses yielded a three factor solution: 1) proactive aggression, 2) reactive aggression due to internal frustration, and 3) reactive aggression due to external provocation. All three factors showed moderate to high correlations. Four classes were detected that mainly differed quantitatively (no ‘proactive-only’ class present), yet also qualitatively when age was taken into account, with reactive aggression becoming more severe with age in the highest affected class yet diminishing with age in the other classes. Findings were robust across the four samples. Multiple regression analyses showed that ‘reactive aggression due to internal frustration’ was the strongest predictor of YSR and CBCL internalizing problems. However, results showed moderate to high overlap between all three factors. Aggressive behavior can be distinguished psychometrically into three factors in a clinical sample, with some differential associations. However, the clinical relevance of these findings is challenged by the person-based analysis showing proactive and reactive aggression are mainly driven by aggression severity.

Differences in Inhibitory Control between Impulsive and Premeditated Aggression in Juvenile Inmates

Inhibitory control dysfunction was considered a universal characteristic of violent offenders. The aim of this study was to examine differences in inhibitory control between two subtypes of violent youth; those displaying predominantly impulsive and those presenting predominantly premeditated aggression (PM). Forty-four juvenile offenders, defined on the basis of the Procedures for the Classification of Aggressive/Violent Acts (Stanford and Barratt, 2001) participated (N = 23: impulsive; N = 21 premeditated). A visual Go/NoGo task was used to compare behavioral responses and event-related potentials (ERPs) between groups. The task contained two letters (W and M), W was the Go stimulus and M the NoGo stimulus. The impulsive youth showed a significantly greater decrease in N2 latency for Go relative to NoGo trials than the premeditated aggressive youth. The differentiation in N2 amplitude between Go and NoGo (N2d) was negatively correlated with impulsivity of aggression. Both groups showed no significant central NoGo P3. Our findings suggest that impulsive violent youth show stronger prepotent responses and impaired conflict monitoring during early inhibitory control processing relative to premeditated aggressive youth. Both impulsive and premeditated violent youth may show impaired response inhibition at the late processing stage of inhibitory control.

Intermittent Explosive Disorder and Substance Use Disorder: Analysis of the National Comorbidity Survey Replication Sample

OBJECTIVE

A relationship between aggression and substance use has been debated for many years. While substance use increases the risk of aggressive behavior, no studies have reported on the relationship between impulsive aggression and substance use/disorder, specifically.

METHODS

We analyzed data from the community-based National Comorbidity Survey Replication (N = 9,282 subjects) in order to examine the relationship between current DSM-5 intermittent explosive disorder (IED), a disorder of impulsive aggression, and current substance use disorders (SUDs), overall, and with regard to alcohol, tobacco, and cannabis use disorders and nondisordered use.

RESULTS

Occurrence of current SUD was elevated in current IED versus non-IED adult subjects, and onset of IED preceded that of SUD in 92.5% of comorbid IED + SUD cases. This relationship was not due to the presence, or absence, of current depressive or anxiety disorders. Examination of the severity of IED and of SUD revealed that the presence of IED increases SUD severity but that the presence of SUD does not increase IED severity.

CONCLUSIONS

Subjects with IED are at increased risk of developing SUD, compared with those without IED. This suggests that history of recurrent, problematic, impulsive aggression is a risk factor for the later development of SUD rather than the reverse. If so, effective treatment of impulsive aggression, before the onset of substance misuse, may prevent, or delay, the development of SUD in young people.

Substance use disorders: Relationship with intermittent explosive disorder and with aggression, anger, and impulsivity

BACKGROUND

A relationship between substance use and aggression has been noted for decades. While substance use appears to be associated with an increased risk of aggressive behavior, no study has yet reported on the pattern of comorbidity and temporal relationship between impulsive aggression (i.e., intermittent explosive disorder) and substance use disorders (SUD), specifically.

METHODS

To specify these relationships, we examined DSM-5 diagnosis data from diagnostic interviews of 1355 adults who met one of five non-overlapping diagnostic subgroups: those with intermittent explosive disorder (IED; n = 339), those with SUD (n = 136), IED+SUD (n = 280), adults with psychiatric disorders but no SUD or IED (n = 320), and healthy

CONTROLS

HC, n = 282).

RESULTS

Occurrence of lifetime SUD was elevated in IED vs. all Non-IED subjects (Odds Ratio: 3.61 [95% CI: 2.82-4.63]) and onset of IED preceded SUD in 80% of comorbid IED+SUD cases. Examination of the severity of impulsive aggression and SUD revealed that IED increased SUD severity but the presence of SUD did not increase severity of IED core features, including aggression, anger, or impulsivity.

CONCLUSIONS

Subjects with IED are at increased risk of developing substance use disorder, compared to those without IED. This suggests that history of recurrent, problematic, impulsive aggression is a risk factor for the later development of SUD rather than the reverse. Thus, effective treatment of impulsive aggression, before the onset of substance misuse, may prevent or delay the development of SUD in young individuals.

Impulsive versus premeditated aggression in the prediction of violent criminal recidivism

Past aggression is a potent predictor of future aggression and informs the prediction of violent criminal recidivism. However, aggression is a heterogeneous construct and different types of aggression may confer different levels of risk for future violence. In this prospective study of 91 adults in a pretrial diversion program, we examined (a) premeditated versus impulsive aggression in the prediction of violent recidivism during a one-year follow-up period, and (b) whether either type of aggression would have incremental validity in the prediction of violent recidivism after taking into account frequency of past general aggression. Findings indicate that premeditated, but not impulsive, aggression predicts violent recidivism. Moreover, premeditated aggression remained a predictor of recidivism even with general aggression frequency in the model. Results provide preliminary evidence that the assessment of premeditated aggression provides relevant information for the management of violent offenders.

Validation of the Impulsive/Premeditated Aggression Scale in Mexican psychiatric patients

INTRODUCTION

Aggression has been linked to several psychiatric disorders. None of the available instruments validated in Mexico is able to classify aggression as impulsive or premeditated. The Impulsive/Premeditated Aggression Scale (IPAS) is a self-report instrument designed to characterize aggressiveness as predominately impulsive or premeditated.

OBJECTIVE

The aim of the study was to determine the validity and reliability of the IPAS in a sample of Mexican psychiatric patients.

METHOD

A total of 163 patients diagnosed with affective, anxiety or psychotic disorder were included. A principal-component factor analysis was performed to obtain construct validity of the IPAS impulsive and premeditated aggression subscales; convergent validity as well as internal consistency of subscales were also determined.

RESULTS

The rotated matrix accounted for 33.4% of the variance. Significant values were obtained for convergent validity and reliability of the IPAS subscales.

CONCLUSION

The IPAS is an adequate instrument, which might be used to differentiate the type of aggressive behavior in Mexican psychiatric patients.

Treatment moderators of cognitive behavior therapy to reduce aggressive behavior: a meta-analysis

Maladaptive aggression in adolescents is an increasing public health concern. Cognitive Behavior Therapy (CBT) is one of the most common and promising treatments of aggression. However, there is a lack of information on predictors of treatment response regarding CBT. Therefore, a meta-analysis was performed examining the role of predictors on treatment response of CBT. Twenty-five studies were evaluated (including 2,302 participants; 1,580 boys and 722 girls), and retrieved through searches on PubMed, PsycINFO and EMBASE. Effect sizes were calculated for studies that met inclusion criteria. Study population differences and specific CBT characteristics were examined for their explanatory power. There was substantial variation across studies in design and outcome variables. The meta-analysis showed a medium treatment effect for CBT to reduce aggression (Cohen'd = 0.50). No predictors of treatment response were found in the meta-analysis. Only two studies did examine whether proactive versus reactive aggression could be a moderator of treatment outcome, and no effect was found of this subtyping of aggression. These study results suggest that CBT is effective in reducing maladaptive aggression. Furthermore, treatment setting and duration did not seem to influence treatment effect, which shows the need for development of more cost-effective and less-invasive interventions. More research is needed on moderators of outcome of CBT, including proactive versus reactive aggression. This requires better standardization of design, predictors, and outcome measures across studies.

The role of emotion regulation in the relations between psychopathy factors and impulsive and premeditated aggression

Given the high rates of aggressive behavior among highly psychopathic individuals, much research has sought to clarify the nature of the relation between psychopathy and aggression. The present study examined relations between Fearless Dominance (PPI FD), Self-Centered Impulsivity (PPI SCI), and Coldheartedness (PPI CH) Factors of the Psychopathic Personality Inventory (PPI; Lilienfeld & Andrews, 1996) and aggression dimensions (premeditated and impulsive aggression) in a sample of substance users receiving inpatient treatment. At the univariate level, PPI FD traits were significantly and positively related to premeditated aggression, but were not significantly related to impulsive aggression. PPI SCI traits were positively related to both forms of aggression, whereas PPI CH was not significantly related to either aggression dimension. Emotion regulation difficulties, as measured by the Difficulties with Emotion Regulation Scale (DERS; Gratz & Roemer, 2004), were negatively related to PPI FD traits, positively related to PPI SCI traits, and negatively related to PPI CH traits. Both PPI SCI and PPI FD traits exerted significant indirect effects on impulsive aggression through the DERS. In contrast, the DERS did not mediate the relations between psychopathic traits and premeditated aggression. Results provide a more nuanced understanding of the psychopathy-aggression relations and suggest that difficulties with emotion regulation may be an important mediator of the relations between psychopathy factors and impulsive aggression.

Motivational dimensions of inpatient aggression

BACKGROUND

Recent studies have suggested that functional classifications of aggression should be used to improve the understanding of the heterogeneity of aggression and its management, among inpatients in psychiatric hospitals.

AIMS

Our aim was to examine a theoretically derived three-factor model for conceptualising aggressive incidents by inpatients as irritable, instrumental or defensive.

METHODS

As part of the routine assessments in a forensic psychiatric high security ward, staff filled out a questionnaire on motives for aggression after all violent incidents. A total of 1652 incidents from 28 patients were analysed by means of exploratory and confirmatory factor analyses.

RESULTS

Support was found for the three-factor model. For the most part, the scale items loaded on the factors as predicted, and the model was able to explain 61% of the data variance. Irritable incidents were the most common, but elevated scores for instrumental characteristics were found as well. High psychopathy scores were associated with incidents scoring high values on both irritable and instrumental dimensions, and low values on the defensive dimensions.

CONCLUSIONS

Confirming these three dimensions of inpatient aggressive incidents may help caregivers' understanding of aggressive behaviour. If confirmed in future studies, this dimensional approach may prove useful for the management of aggressive inpatients.

Reactive and proactive aggression and suicide attempts among criminal offenders

Outwardly-directed aggression is associated with suicide attempts, but aggression is a heterogeneous construct. Increased specificity in our understanding of the link between aggression and suicide attempts can be attained by examining subtypes of aggression. We studied the relationships of reactive and proactive aggression to history of a suicide attempt among 96 criminal offenders in a pretrial supervision program. Consistent with prior findings in non-offender samples, reactive aggression was associated with a history of suicide attempt after controlling for gender and depression. Proactive aggression was unrelated to suicide attempts. Results indicate that suicide risk assessments in forensic settings may be informed by the measurement of reactive aggression.

Subtypes of aggression in patients with schizophrenia: the role of personality disorders

BACKGROUND

Research has repeatedly demonstrated that schizophrenia has a small but significant association with violence. It is further recognised that a subgroup of people with such links also have personality disorders, but the extent to which type of violence or aggression varies according to subgroup is less clear.

AIM

This study aimed to investigate, among co-morbid cases, if the number or type of personality disorders predicts type of aggression.

METHODS

In a cross-sectional study, 108 patients with schizophrenia were assessed for personality disorder, Axis-I diagnosis, verbal IQ, social functioning and type of aggression.

RESULTS

Logistic regression revealed that the more personality disorders identified (Cluster B personality disorders compared with Clusters A and C) and anti-social personality disorder compared with other Cluster B disorders significantly predicted premeditated aggression.

CONCLUSIONS

These findings suggest that detailed personality assessment should be a routine part of comprehensive assessment of patients with schizophrenia. Improved knowledge of the presence and type of personality disorders may help detect and manage the risk of some types of aggression.

Officer attitudes towards intra-group aggression in young people and young adults: does the reported motivation of an aggressor impact on intervention and support?

The present study aims to assess whether global and context specific attitudes influence the ability to correctly identify the motivation for aggression and selection of appropriate intervention strategies. A sample of 105 prison officers completed a measure assessing global attitudes towards prisoners, one assessing context specific attitudes towards aggression, and also a case vignette. Officers were asked to consider the motivation for aggression and to select an appropriate intervention. It was predicted that sex, age and level of experience would impact on global and context specific attitudes. Officers expressing positive global attitudes and non-aggressive context specific attitudes were expected to be more able to identify the motivation for aggression and more likely to adopt a rehabilitative approach. There was evidence to indicate sex differences in global and context specific attitudes but no impact of age. Level of experience of aggression impacted both on global and context specific attitudes. Global or context specific attitudes did not influence the ability to interpret aggression, but aggression type did. Limitations and directions for future research are discussed.

Predatory violence aiming at relief in a case of mass murder: Meloy's criteria for applied forensic practice

Mass murder is the result of the complex interaction of several factors. What seems ubiquitous within mass murder are extreme feelings of anger and revenge. Yet despite these intense affective states, mass murders are, as a rule, not behaviorally impulsive, but rather prepared. The presence of extreme hate and anger evokes an impulsive outburst of rage, whereas planning and premeditation point in the direction of a cognitive, rather unemotional deed. This inconsistency is also reflected in reports of offenders' emotional states during the execution of their crimes: while some mass murderers have been described as calm, focused and emotionless during the events, others have shown signs of hostility, confusion, and distress. Considering mass murder from the perspective of its violence mode might shed some light on its nature and dynamics. With respect to the differentiation between affective and predatory violence, Meloy (1988) developed a model for applied forensic practice. The fully documented case of mass murder discussed in this study contains nine indices of predatory violence and one of affective violence. Furious affects of hate and anger were present but appeared to precede the cold-blooded killings. As a matter of fact, it is argued that the offender carried out the predatory murder in order to alleviate the psychological tension and symptoms generated by these severe ego-dystonic affects. The offender thus didn't seem to strive for narcissistic gratification of omnipotence, but rather seemed to aim to solve a problem.

Childhood physical abuse, aggression, and suicide attempts among criminal offenders

Childhood physical abuse (CPA) has numerous short and long-term negative effects. One of the most serious consequences of CPA is an increased risk for suicide attempts. Clarifying the mechanisms by which CPA increases risk for suicidal behavior may enhance preventive interventions. One potential mechanism is a tendency toward aggression. In a sample of 266 criminal offenders, ages 18-62, we examined the relationships among CPA, lifetime aggression, and suicide attempts and tested lifetime history of aggression as a mediator of the relationship between CPA and suicide attempts. Results indicated that CPA and aggression were associated with suicide attempts. Consistent with our hypothesis, lifetime aggression mediated the CPA and suicide attempts relationship. Findings suggest that aggression may be an important mediator of the relationship between CPA and suicide attempts among criminal offenders, and are consistent with the possibility that treating aggression may reduce risk for suicide attempts.

Do personality characteristics and beliefs predict intra-group bullying between prisoners?

This study assesses how beliefs about aggression and personality can predict engagement in intra-group bullying among prisoners. A sample of 213 adult male prisoners completed the DIPC-SCALED (bullying behavior), the EXPAGG (beliefs toward aggression), and the IPIP (a five-factor measure of personality). It was predicted that bullies would hold greater instrumental beliefs supporting the use of aggression than the other categories, with perpetrators reporting lower scores on agreeableness, conscientiousness, and openness to experience, and higher scores on neuroticism (i.e. low scores on emotional stability) than the remaining sample. Bullies and bully-victims endorsed greater instrumental aggressive beliefs than the victim category. Only one perpetrator group, bullies were predicted by reduced levels of agreeableness and increased levels of neuroticism, whereas bully/victims were predicted by decreased levels of neuroticism. Limitations of this study and directions for future research are discussed.

Psychopathy and axis I psychiatric disorders among criminal offenders: relationships to impulsive and proactive aggression

Both psychopathology and aggression are heterogeneous constructs. Determining which forms of psychopathology relate to risk for different classes of aggressive behavior has implications for risk recognition and management. This study examined the relationships of impulsive aggression (IA) and proactive aggression (PA) to psychopathy and symptoms of several Diagnostic and Statistical Manual Axis I disorders in a sample of criminal offenders. Results replicated prior findings from community samples of a broad relationship between psychopathology and IA. PA was related only to psychopathy. An interaction was found whereby IA was associated with impulsive-antisocial traits of psychopathy only for individuals with moderate to high levels of generalized anxiety. Results indicate that assessing and treating several Axis I disorders in offenders may decrease risk for IA. Moreover, current findings raise the possibility that generalized anxiety is a key, modifiable component of the relationship between IA and impulsive-antisocial traits.

A test of the reactive aggression-suicidal behavior hypothesis: is there a case for proactive aggression?

A large body of literature suggests that aggressive behavior can be classified into two subtypes--reactive aggression (RA) and proactive aggression (PA)--which differ on dimensions of emotional arousal, control, and impulsivity. A longstanding hypothesis posits that RA underlies the association between aggression and suicidal behavior, with the implicit assumption that PA is unrelated to suicidal behavior. However, no empirical study to date has specifically investigated this question. The authors examined associations of RA and PA with suicide attempts and suicidal ideation among 878 male and female patients in substance-dependence treatment programs. They also examined the moderating effects of sex. Contrary to hypotheses, PA was associated with both suicide attempts and suicidal ideation. RA was also associated with both outcomes in unadjusted analyses but became nonsignificant for suicide attempts in multivariate analyses. Moreover, sex served as a moderator, with PA showing an association with suicide attempt among men but not women. Results indicate the need for additional studies of PA and suicidal behavior.

Predicting short-term institutional aggression in forensic patients: a multi-trait method for understanding subtypes of aggression

Accurately predicting inpatient aggression is an important endeavor. The current study investigated inpatient aggression over a six-month time period in a sample of 152 male forensic patients. We assessed constructs of psychopathy, anger, and active symptoms of mental illness and tested their ability to predict reactive and instrumental aggression. Across all levels of analyses, anger and active symptoms of mental illness predicted reactive aggression. Traits of psychopathy, which demonstrated no relationship to reactive aggression, were a robust predictor of instrumental aggression. This study (a) reestablishes psychopathy as a clinically useful construct in predicting inpatient instrumental aggression, (b) provides some validation for the reactive/instrumental aggression paradigm in forensic inpatients, and (c) makes recommendations for integrating risk assessment results into treatment interventions.

Differentiating impulsive and premeditated aggression: self and informant perspectives among adolescents with personality pathology

Previous research has articulated the conceptual differentiation of impulsive and premeditated aggression. Little, if any, of this research has examined personological differences among adolescents with aggression-oriented pathology, and little, if any, has examined both self and informant perspectives. The current study examined such differentiation within a Conduct Disorder population in which normal and pathological personality characteristics were examined via self- and informant-report. Results indicated the two forms of aggression were independent: high impulsive aggression was associated with high Neuroticism, but high premeditated aggression was associated with low Agreeableness and high Extraversion. Overall, adolescents high in impulsive aggression had a pattern of personality characteristics that are seen as socially-detached and emotionally volatile. In contrast, adolescents high in premeditated aggression had a pattern of characteristics seen as egocentric and socially-engaged but without concern for others. The results have implications for the social and motivational mechanisms producing the two forms of aggression.

Empathic deficits and alexithymia in trauma-related impulsive aggression

Our long term interest is to develop a developmental model of impulsive aggression based on a confluence of social, psychological and biological features. This approach incorporates neurobiological research, which has identified language processing deficits as a unique characteristic of impulsive aggressors and extends it to include emotional deficits. As an initial test of this hypothesis, we examined whether empathy and alexithymia were associated with impulsive aggression. Regressions were performed to explore the associations among impaired empathy, alexithymia, impulsive aggression, verbal and physical general aggression. Among impulsive aggressive veterans (n=38) recruited from a VA trauma clinic, alexithymia predicted impulsive aggression and empathic deficits predicted verbal aggression. Neither emotional awareness deficit predicted general physical aggression in this middle-aged sample. Results suggested that empathic deficits were associated with general verbal aggression, but alexithymia was uniquely associated with impulsive aggression. Consideration of alexithymia in impulsive aggression has implications for its etiology, prevention and treatment.

Comparison of impulsive and premeditated perpetrators of intimate partner violence

Violence occurs in four to five million intimate relationships each year in the United States. Past research has investigated the concept of batterer subtypes based on the nature of the violent behavior. To extend this research, the present study used the Impulsive/Premeditated Aggression Scale (IPAS) along with a battery of relevant self-report measures in a sample of men (N = 113) convicted of domestic violence and court ordered into an intervention program. Batterers whose violence was classified as premeditated scored higher on psychopathic traits and a measure of treatment rejection. Batterers whose violence was classified as impulsive in nature reported a wider range of serious psychopathology. It is suggested that the use of a bimodal classification (Impulsive/Premeditated) in batterers may have significant clinical and legal policy implications.

Impulsive and premeditated subtypes of aggression in conduct disorder: differences in time estimation

Research aimed at identifying and studying subtypes of aggression have historically dichotomized aggressive subtypes, although specific nomenclature has varied; one approach has been to classify aggressive behavior as predominantly impulsive or predominantly premeditated. There are a number of behavioral and cognitive differences between those exhibiting these different forms of aggression. This study was designed to extend understanding of the impulsive/premeditated aggression dichotomy by comparing time estimation among adolescents exhibiting predominantly impulsive or predominantly premeditated forms of physical aggression who have a psychiatric diagnosis of conduct disorder (CD). Time estimation has previously been shown to be disrupted in impulsive and some aggressive individuals. Time estimation was compared between healthy Controls (n = 37) and two groups of adolescents with CD, those with histories of either predominantly impulsive (CD-Impulsive, n = 26) or predominantly premeditated (CD-Premeditated, n = 38) aggressive behaviors. Participants completed five computerized trials during which they estimated when 1 min had passed. Among aggressive adolescents with CD, the misperception of time was specific to those with histories of impulsive aggression, although time estimates improved with repeated testing and performance feedback. This study confirms the importance of considering the role and type of physical aggression when studying heterogeneous diagnostic groups like CD and supports the relevance of time estimation to certain subgroups of adolescents with CD.

Characterizing aggressive behavior with the Impulsive/Premeditated Aggression Scale among adolescents with conduct disorder

This study extends the use of the Impulsive/Premeditated Aggression Scale for subtyping aggressive behavior among adolescents with Conduct Disorder. Of the Conduct Disorder symptoms, aggression has the strongest prognostic and treatment implications. While aggression is a complex construct, convergent evidence supports a dichotomy of impulsive and premeditated aggressive subtypes that are qualitatively different from one another in terms of phenomenology and neurobiology. Previous attempts at measuring subtypes of aggression in children and adults are not clearly generalizable to adolescents. Sixty-six adolescents completed a questionnaire for characterizing aggression (Impulsive/Premeditated Aggression Scale), along with standard measures of personality and general functioning. Principal components analysis demonstrated two stable factors of aggression with good internal consistency and construct validity. Compared to the premeditated aggression factor, the impulsive aggression factor was associated with a broader range of personality, thought, emotional, and social problems. As in the adult and child literature, characterization of aggressive behavior into two subtypes appears to be relevant to understanding individual differences among adolescents with Conduct Disorder.

Reliability of the Impulsive-Premeditated Aggression Scale (IPAS) in treated opiate-dependent individuals

The purpose of the study was to evaluate the internal consistency and test-retest reliability of the Impulsive Aggression (IA) and Premeditated Aggression (PM) scales of the Impulsive-Premeditated Aggression Scale (IPAS) in male and female substance-dependent patients, and to compare the findings to those obtained on widely used, validated measures of aggression. Using a sample of 121 patients (61 women) in methadone maintenance treatment, 69 (35 women) of which were re-evaluated after a minimum of 2weeks, the IPAS scales showed acceptable internal consistency (alpha>.72) and test-retest reliability (ICC>.54). These results were comparable to the other aggression measures, and results among women were comparable to men. This was the first study to examine the IPAS scales in a substance use population, to contain a sufficient sample of women for sub-analyses, and to examine the stability of the measure. Findings support the internal consistency and test-retest reliability of the IPAS in male and female opiate-dependent individuals.

Empirical basis and forensic application of affective and predatory violence

The objective of this paper is to address the empirical basis and forensic application of a bimodal theory of violence. The definitions of affective and predatory violence, the relevant animal and clinical research, and the current empirical evidence in neurochemistry, neuropsychology and psychophysiology are reviewed. Forensic evidence for the relevance of this bimodal theory is investigated. An appropriate methodology for data gathering, and two observational measures along with one self-report measure are explicated. Integration of this bimodal theory into forensic practice is suggested. Affective and predatory modes of violence represent an empirically valid bimodal theory of violence, find application in forensic psychiatry, and scientifically deepen the understanding of discrete violent acts for both retrospective and prospective psychiatric and psychological investigations. This bimodal theory of violence should have a place in forensic psychiatric practice.