Neurobiological correlates of violent behavior among persons with schizophrenia

Brain structural alterations associated with impulsiveness in male violent patients with schizophrenia

BACKGROUND

Violence in schizophrenia (SCZ) is a phenomenon associated with neurobiological factors. However, the neural mechanisms of violence in patients with SCZ are not yet sufficiently understood. Thus, this study aimed to explore the structural changes associated with the high risk of violence and its association with impulsiveness in patients with SCZ to reveal the possible neurobiological basis.

METHOD

The voxel-based morphometry approach and whole-brain analyses were used to measure the alteration of gray matter volume (GMV) for 45 schizophrenia patients with violence (VSC), 45 schizophrenia patients without violence (NSC), and 53 healthy controls (HC). Correlation analyses were used to examine the association of impulsiveness and brain regions associated with violence.

RESULTS

The results demonstrated reduced GMV in the right insula within the VSC group compared with the NSC group, and decreased GMV in the right temporal pole and left orbital part of superior frontal gyrus only in the VSC group compared to the HC group. Spearman correlation analyses further revealed a positive correlation between impulsiveness and GMV of the left superior temporal gyrus, bilateral insula and left medial orbital part of the superior frontal gyrus in the VSC group.

CONCLUSION

Our findings have provided further evidence for structural alterations in patients with SCZ who had engaged in severe violence, as well as the relationship between the specific brain alterations and impulsiveness. This work provides neural biomarkers and improves our insight into the neural underpinnings of violence in patients with SCZ.

Aberrant brain structure in patients with schizophrenia and violence: A meta-analysis

Previous studies have indicated that schizophrenia is associated with an increased risk of violence, which may constitute a public health concern, leading to poor treatment outcomes and stigmatization of patients. Investigating brain structural features of violence in schizophrenia could help us understand its specific pathogenesis and find effective biomarkers. Our study aimed at identifying reliable brain structural changes associated with violence in patients with schizophrenia by conducting a meta-analysis and meta-regression of magnetic resonance imaging studies. Specific brain changes in patients with schizophrenia and violence (VSZ) were studied, compared with patients with schizophrenia and violence (VSZ), patients with non-violent schizophrenia (NVSZ), and individuals with a history of violence only and health controls. Primary outcomes revealed that there was no significant difference of gray matter volume between patients with VSZ and patient with NVSZ. Compared with controls, patients with VSZ exhibited decreased gray matter volume in the insula, the superior temporal gyrus (STG), the left inferior frontal gyrus, the left parahippocampus, and the right putamen. Compared with individuals with a history of violence only, patients with VSZ exhibited decreased volume in the right insula and the right STG. Meta-regression analysis revealed a negative correlation between the duration of schizophrenia and the volume of the right insula in patients with VSZ. These findings may suggest a shared neurobiological basis for both violence and psychiatric symptoms. The impaired frontotemporal-limbic network may serve as a neurobiological basis for higher prevalence of violent behaviour in patients with schizophrenia. However, it is important to note that these changes are not unique to patients with VSZ. Further investigation is needed to explore the neural mechanism that drive the interaction between violent behaviour and specific aggression-related dimensions of schizophrenia.

Neurocognitive Suicide and Homicide Markers in Patients with Schizophrenia Spectrum Disorders: A Systematic Review

Suicide and homicide are considered important problems in public health. This study aims to identify the cognitive performance of suicidal and homicidal behaviors in people with schizophrenia spectrum disorders, as well as examining whether there are shared neuropsychological mechanisms. A systematic review of the recent literature was carried out from September 2012 to June 2022 using the Medline (via PubMed), Scopus, Embase, and Cochrane databases. Among the 870 studies initially identified, 23 were finally selected (15 related to suicidal behaviors and 8 to homicidal behaviors). The results evidenced a relationship between impairment of cognitive performance and homicidal behavior; meanwhile, for suicidal behaviors, no consistent results were found. High neuropsychological performance seems to act as a protective factor against violent behavior in people with schizophrenia spectrum disorders, but not against suicidal behavior; indeed, it can even act as a risk factor for suicidal behavior. To date, there is insufficient evidence that shared neurocognitive mechanisms exist. However, processing speed and visual memory seem to be affected in the presence of both behaviors.

Characteristics and associated factors of violence in male patients with schizophrenia in China

Objective

To investigate the characteristics and associated factors of violence in male patients with schizophrenia in China.

Methods

A total of 507 male patients with schizophrenia were recruited, including 386 non-violent and 121 violent patients. The socio-demographic information and medical history of the patients were collected. Psychopathological characteristics, personality traits psychopathology, and factors related to risk management were assessed using the Brief Psychiatric Rating Scale (BPRS), the History of Violence, Clinical, Risk Assessment Scale (HCR-20), and the Psychopathy Checklist-Revised (PCL-R), as appropriate. Differences in these factors were compared between the violent and non-violent patients, and logistic regression analysis was performed to explore the risk factors for violence in male patients with schizophrenia.

Results

The results showed that the violent group had a lower level of education, longer duration of illness, as well as a higher rate of hospitalization, history of suicidal attempts, and history of alcohol compared with the non-violent group. The violent group scored higher in items of symptoms in BPRS, personality traits and psychopathy in PCL-R, and risk management in HCR-20. The regression analysis showed that previous suicidal behavior (OR = 2.07,95% CI [1.06-4.05], P = 0.033), antisocial tendency in PCL-R (OR = 1.21, 95% CI [1.01-1.45], P = 0.038), H2: young age at violent incident (OR = 6.39, 95% CI [4.16-9.84], P < 0.001), C4: impulsivity (OR = 1.76, 95% CI [1.20-2.59], P = 0.004), and H3: relationship instability (OR = 1.60, 95% CI [1.08-2.37], P = 0.019) in HCR-20 were risk factors of violence among male patients with schizophrenia.

Conclusion

The present study found significant differences in socio-demographic information, history of treatment, and psychopathy characteristics between male patients with schizophrenia who had engaged in violent behaviors and their non-violent counterparts in China. Our findings suggested the necessity of individualized treatment for male patients with schizophrenia who had engaged in violent behaviors as well as the use of both HCR-20 and PCL-R for their assessment.

Smaller amygdala subnuclei volume in schizophrenia patients with violent behaviors

To investigate the association between the volume of amygdala subnuclei and violent behaviors in patients with schizophrenia (SCZ). In the present study, we recruited 40 SCZ patients with violent behaviors (VS), 26 SCZ patients without violent behaviors (NVS), and 28 matched healthy controls (HC) who completed T1-weighted magnetic resonance imaging. Both the total amygdala and amygdala subnuclei volumes were estimated with FreeSurfer. When comparing the SCZ patients with HC, SCZ patients had a smaller volume of the left basal nucleus (P < 0.05, uncorrected). Further, the VS patients had a smaller volume of the left amygdala central nucleus than the NVS group (P < 0.05, Bonferroni corrected). Our study suggests that a smaller volume of the left amygdala basal nucleus may be a biomarker for SCZ and that a smaller volume of the left central nucleus may be relevant to violence risk in patients with schizophrenia.

Neurocognitive features, personality traits, and social function in patients with schizophrenia with a history of violence

Recent literature examining associations between cognitive function, clinical features, and violence in patients with schizophrenia has been growing; however, the results are inconsistent. Reports on social function and personality are limited. These studies are yet to be reflected in risk assessment tools and management plans. The aim of this study is to provide a resource for risk assessment and intervention studies by conducting multifaceted well-established assessments in a large population. Data from 355 patients with schizophrenia (112 patients with a history of violence; 243 patients without a history of violence) and 1265 healthy subjects were extracted from a large database of individuals with mental disorders in a general psychiatric population in Japan. The associations between violence in patients with schizophrenia and intellectual function, cognitive function (memory function, executive function, attentional function, verbal learning, processing speed, social cognition), clinical variables, personality traits, social function, and quality of life (QOL) were analyzed. Compared with healthy subjects, the schizophrenia group had broadly impaired cognitive function and social cognition, and their personality traits showed similar differences as those reported previously. Patients with schizophrenia with a history of violence showed significantly more impaired visual memory function (P = 1.9 × 10^-5, Cohen's d = 0.34), longer hospitalization (P = 5.9 × 10^-4, Cohen's d = 0.38), more severe excited factor on Positive and Negative Syndrome Scale (P = 1.6 × 10^-4, Cohen's d = 0.47), higher self-transcendence personality construct on the Temperament and Character Inventory (P = 1.8 × 10^-4, Cohen's d = 0.46), and shorter total working hours per week (P = 4.8 × 10^-4, Cohen's d = 0.53) than those with schizophrenia without a history of violence. New findings, including impaired visual memory, a high self-transcendence personality trait, and shorter total working hours, could be focused on in future interventional research.

Review on Selected Aggression Causes and the Role of Neurocognitive Science in the Diagnosis

Simple Summary

Aggression in dogs is often a reason for abandonment and/or euthanasia. Recently, knowledge about aggression has been subjected to more detailed analysis. In recent years, it has been studied in terms of factors affecting it, such as diet (especially nutritional supplements) and physiology (endocrine system). In addition, recently, new methods of brain research, such as neurocognitive research, have appeared, which enable a significant increase in knowledge about dog behavior, including aggression.

Abstract

Aggression as a behavior is not always desirable, often ends in abandonment and/or euthanasia. However, it is possible to prevent the occurrence of unwanted aggression in domestic dogs. Aggression is not a fully understood phenomenon. In recent years, many studies have focused on the influence of diet and physiology (including the endocrine system) on the emergence of behavioral disorders. In particular, the emphasis was put on nutritional additives such as fatty acids, amino acids, and probiotics. In addition, the possibility of using neurocognition in the observation of abnormal behavior in dogs has also been discussed, which may allow for a more detailed determination of the basis of aggressive behavior in dogs. In this review, the concepts related to aggression and its potential causes have been gathered. In addition, the possible influence of diet and hormones on aggression in dogs has been discussed, as well as the application of neurocognition in the possibility of its diagnosis.

Structural Deficits in the Frontotemporal Network Associated With Psychopathic Traits in Violent Offenders With Schizophrenia

People with schizophrenia (SZ) are at increased risk of violence compared to the general population. However, the neural mechanisms of violent behavior in patients with SZ are still unclear due to the heterogeneity of the diseased population. In this study, we aimed to examine the neural correlates of violent behavior in SZ and to determine whether the structural deficits were related to psychopathic traits. A total of 113 participants, including 31 SZ patients with violent behavior (vSZ), 39 SZ patients without violent behavior (nvSZ), and 43 healthy controls (HC), completed the T1-weighted magnetic resonance imaging (MRI) scan and were analyzed using voxel-based morphometry approach. The psychopathic traits were assessed using the Psychopathy Checklist: Screening Version (PCL:SV). The results showed decreased gray matter volume (GMV) in the vSZ group in the right temporal lobe and bilateral inferior frontal gyri compared to HCs; while reduced GMV in the inferior parietal lobe, parahippocampal and orbital frontal gyri was found in the nvSZ group compared with HCs. Correlation analyses showed that psychopathic traits were negatively associated with the GMV in the right superior temporal and left fusiform gyri in the vSZ group, indicating that psychopathic traits, as reflected by the score of antisocial factor, might be related to structural deficits in the temporal lobe, which led to a propensity to violent behavior in patients with SZ. Our findings suggest that violent behavior in patients with SZ might have a personality background associated with the frontotemporal network aberrance. In future studies, we need to take a closer look at psychopathic traits for better understanding of the mechanism of interpersonal violence in patients with SZ and to explore whether the imaging findings from this study can serve as a biomarker to predict future violent behaviors and community living.

Violence, neurocognitive function and clinical correlates in patients with schizophrenia

BACKGROUND

Schizophrenia patients with violent behavior are a severe public health concern, but the correlates of this violent behavior are unknown. Additionally, the relationship between neurocognitive function and violent behavior in Chinese patients with schizophrenia has not yet been investigated.

METHODS

A total of 337 schizophrenia inpatients were recruited. The Positive and Negative Syndrome Scale (PANSS) was used to assess psychopathological symptoms. Neurocognitive functioning was evaluated using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS).

RESULTS

The percentage of violent behavior was 10.4% in patients with schizophrenia. Patients with violent behavior had higher PANSS-positive, excited, and total subscale scores than patients who did not show violent behavior. Patients with violent behavior also had lower RBANS language, semantic fluency, and total subscale scores. Gender (OR = 0.066∼0.819, p = 0.023), illness duration (OR = 0.876∼0.971, p = 0.002), smoking (OR = 1.127∼2.950, p = 0.014), the PANSS positive subscale (OR = 1.050∼1.197, p = 0.001), and the RBANS language subscale (OR = 0.927∼0.987, p = 0.005) significantly contributed to the development of violent behavior in schizophrenia patients.

CONCLUSION

Our findings revealed that cognitive and clinical assessments should be considered in comprehensive assessments of future risks of violence in schizophrenia patients.

Processing of Spoken Emotions in Schizophrenia: Forensic and Non-forensic Patients Differ in Emotional Identification and Integration but Not in Selective Attention

Patients with schizophrenia (PwS) typically demonstrate deficits in visual processing of emotions. Less is known about auditory processing of spoken-emotions, as conveyed by the prosodic (tone) and semantics (words) channels. In a previous study, forensic PwS (who committed violent offenses) identified spoken-emotions and integrated the emotional information from both channels similarly to controls. However, their performance indicated larger failures of selective-attention, and lower discrimination between spoken-emotions, than controls. Given that forensic schizophrenia represents a special subgroup, the current study compared forensic and non-forensic PwS. Forty-five PwS listened to sentences conveying four basic emotions presented in semantic or prosodic channels, in different combinations. They were asked to rate how much they agreed that the sentences conveyed a predefined emotion, focusing on one channel or on the sentence as a whole. Their performance was compared to that of 21 forensic PwS (previous study). The two groups did not differ in selective-attention. However, better emotional identification and discrimination, as well as better channel integration were found for the forensic PwS. Results have several clinical implications: difficulties in spoken-emotions processing might not necessarily relate to schizophrenia; attentional deficits might not be a risk factor for aggression in schizophrenia; and forensic schizophrenia might have unique characteristics as related to spoken-emotions processing (motivation, stimulation).

Effects of Integrated Violence Intervention on Alexithymia, Cognitive, and Neurocognitive Features of Violence in Schizophrenia: A Randomized Controlled Trial

Patients with schizophrenia and repetitive violence express core impairments that encompass multiple domains. To date, there have been few interventions integrating neurocognition, social cognition, alexithymia, and emotion regulation together as an approach to manage repetitive violence. The aim of this open-label randomized controlled trial was to examine more comprehensively the effectiveness of a novel Integrated Cognitive Based Violence Intervention Program on management of repetitive violence in patients with schizophrenia (vSZ). Sixty recruited patients were aged ≥20 years, diagnosed with schizophrenia for >2 years, had repetitive violent behavior within one year, and were psychiatrically hospitalized. The vSZ patients were randomly allocated to two groups and received either the intervention or treatment as usual. The intervention module, consisting of all defined 11 cognitive and social cognitive domains as well as emotion regulation, which were grouped into four modules. The intervention placed emphasis on the patients’ behavioral problems or intrinsic conflicts in relation to repetitive violence. The results indicate a statistically significant trend toward reducing impulsivity, anger with resentment, physical aggression, suspicion, and hostility (p < 0.05). The intervention significantly alleviated the intensity of cognitive failure, improved the management of alexithymic features and attribution styles and errors, and fostered adequate decision-making styles and emotion regulation capacity (p < 0.05). The intervention, when applied in conjunction with psychiatric standard care, could exert synergistic effects on alexithymia and cognitive, clinical, and neurocognitive features of repetitive violence in schizophrenia. This intervention provided patients a more active role to manage their violent behavior with the involvement of alexithymia.

Brain gray matter differences among forensic psychiatric patients with psychosis and incarcerated individuals without psychosis: A source-based morphometry study

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We employed source-based morphometry to examine grey matter differences in forensic psychiatric patients with psychosis versus incarcerated controls without psychosis.

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Compared to the psychotic group, the non-psychotic group demonstrated greater loading weights in the superior, transverse, and middle temporal gyrus and the anterior cingulate.

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Compared to the non-psychotic group, the psychotic group exhibited greater loading weights in the frontal pole, precuneus, basal ganglia, thalamus, parahippocampal gyrus, and visual cortex.

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Neuroimaging investigations of offenders with psychosis ought to control for the level of psychopathic traits present.

Background

While psychosis is a risk factor for violence, the majority of individuals who perpetrate aggression do not present psychotic symptoms. Pathological aggressive behavior is associated with brain gray matter differences, which, in turn, has shown a relationship with increased psychopathic traits. However, no study, to our knowledge, has ever investigated gray matter differences in forensic psychiatric patients with psychosis compared with incarcerated individuals without psychosis matched on levels of psychopathic traits. Here, we employed source-based morphometry (SBM) to investigate gray matter differences in these two populations.

Methods

We scanned 137 participants comprising two offender subgroups: 69, non-psychotic incarcerated offenders and 68, psychotic, forensic psychiatric patients. Groups showed no difference in age, race, ethnicity, handedness, and Hare Psychopathy Checklist-Revised scores. Source-based morphometry was utilized to identify spatially distinct sets of brain regions where gray matter volumes covaried between groups. SBM is a data-driven, multivariate technique that uses independent components analysis to categorize groups of voxels that display similar variance patterns (e.g., components) that are compared across groups.

Results

SBM identified four components that differed between groups. These findings indicated greater loading weights in the superior, transverse, and middle temporal gyrus and anterior cingulate in the non-psychotic versus psychotic group; greater loading weights in the basal ganglia in the psychotic versus non-psychotic group; greater loading weights in the frontal pole, precuneus, and visual cortex among psychotic versus non-psychotic offenders; and greater loading weights in the thalamus and parahippocampal gyrus in psychotic versus non-psychotic groups.

Conclusions

Two different offender groups that perpetrate violence and show comparable levels of psychopathic traits evidenced different gray matter volumes. We suggest that future studies of violent offenders with psychosis take psychopathic traits into account to refine neural phenotypes.

Violent Behavior Is Associated With Emotion Salience Network Dysconnectivity in Schizophrenia

Background: Despite individuals with schizophrenia being at an elevated risk of violence compared to the general population, limited efforts have been invested in investigating the neurobiological etiology explaining the increase. Among the few studies examining functional disruptions pertaining to violent schizophrenia patients using fMRI, only one study has considered functional connectivity. The current state of knowledge does not allow to infer deficits in functional connectivity specific to distinct cognitive/emotional states that have been associated with the emergence of violence in schizophrenia, such as negative emotion processing. This study sought to identify disrupted connectivity among men with schizophrenia and a history of violence (SCZ+V), compared to men with schizophrenia without a history of violence (SCZ-V) and healthy controls, during negative emotion processing using fMRI. Methods: Twenty SCZ+V, 19 SCZ-V, and 21 healthy men were scanned while viewing negative images. Results: Negative images elicited an increased connectivity between the dorsal anterior cingulate cortex (dACC) and the bilateral rostral prefrontal cortex (rPFC), as well as a decreased functional connectivity between the frontal regions (bilateral rPFC and dACC) and the putamen and hippocampus in SCZ+V men as compared to SCZ-V men and healthy controls. Concurrently, the centrality of the dACC within the network was reduced in SCV+V subjects. Conclusions: These results suggest an inefficient integration of the information by the dACC between frontal and limbic regions in SCZ+V men during negative emotion processing and highlight the importance of the ACC in the neurobiological bases of violent behavior in schizophrenia.

Voxel-Based Morphometry Correlates of an Agitated-Aggressive Syndrome in the At-Risk Mental State for Psychosis and First Episode Psychosis

There are mixed reports on structural neuroimaging correlates of aggression in schizophrenia with weak evidence due to cohort overlaps and lack of replications. To our knowledge, no study examined volumetric neuroimaging correlates of aggression in early stages of psychosis. An agitated-aggressive syndrome is present in at-risk mental state (ARMS) and in first-episode psychosis (FEP) - it is unclear whether this syndrome is associated with structural brain abnormalities in early stages of psychosis. Using three-dimensional magnetic resonance imaging and a whole brain voxel-based morphometry approach, we examined 56 ARMS patients, 55 FEP patients and 25 healthy controls. We operationalized aggression using the Excited Component of the Brief Psychiatric Rating Scale (BPRS-EC) and dichotomized our patient group by median split into "BPRS-EC high" (n = 49) and "BPRS-EC low" groups (n = 62). The "BPRS-EC high" group had significantly smaller left lingual gyrus volume than HC. This finding was not present in the "BPRS-EC low" group. In addition, grey matter volume in the left lingual gyrus showed a negative linear correlation with BPRS-EC over all subjects (ρ = -0.318; p = 0.0001) and in the patient group (ρ = -0.202; p = 0.033). These findings provide first hints on structural brain abnormalities associated with an agitated-aggressive syndrome in ARMS and FEP patients.

A review of factors associated with severe violence in schizophrenia

BACKGROUND

There is a modest but consistent association between violence and schizophrenia. The consequences of serious violence could be catastrophic for the victims, as well as the patients themselves and the community. Any knowledge that would help to prevent acts of serious violence would be of considerable value for the individual and the society.

AIM

To identify external and clinical risk factors for serious violence in schizophrenia, in addition to considering the strength of the association between the factors assessed and severe violence.

METHODS

This was accomplished by a literature survey. One-hundred and two relevant papers were identified that were published during the past 20 years. Forty-four papers were assessed for eligibility. In all, 27 studies including clinical or cognitive variables were reviewed systematically. An effect size was reported where an odds ratio (OR) could be identified or calculated from available data. Five external factors and six clinical domains were evaluated.

RESULTS

Substance abuse is robustly linking schizophrenia and violence. Among the clinical factors, insight, impulsivity, psychopathy, motor speed and a global measure of cognition are the factors with the strongest empirical evidence for an association with severe violence.

CONCLUSION

This is the first systematic review of risk factors for severe violence in schizophrenia, in which a great number of clinical and external factors have been evaluated. Most of the clinical factors have been compared on effect size. The identified factors that represent an increased risk of violence in patients with schizophrenia should be included in risk assessments.

Shared and differential cortical functional abnormalities associated with inhibitory control in patients with schizophrenia and bipolar disorder

Schizophrenia (SZ) and bipolar I disorder (BD-I) share genetic risk factors and cognitive impairments, but these conditions may exhibit differences in cortical functioning associated with inhibitory control. We measured hemodynamic responses during a stop-signal task using near-infrared spectroscopy (NIRS) in 20 patients with SZ, 21 patients with BD-I and 18 healthy controls (HCs). We used stop-signal reaction time (SSRT) to estimate behavioural inhibition. Compared with HCs, patients with either SZ or BD-I exhibited significantly reduced activation in the bilateral inferior, middle and superior frontal gyri. Furthermore, patients with BD-I showed inactivation of the right superior temporal gyri compared with patients with SZ or HCs. Patients with SZ or BD-I demonstrated significant negative correlations between SSRT and hemodynamic responses of the right inferior frontal gyrus. Moreover, patients with SZ exhibited correlations in the middle and superior frontal gyri. Our findings suggest that right inferior frontal abnormalities mediate behavioural inhibition impairments in individuals with SZ or BD-I. Differential patterns of orbitofrontal or superior temporal functional abnormalities may reflect important differences in psychopathological features between these disorders.

Locked in and Growing Old: The Psychiatric, Forensic, and Cognitive Correlates of 30 Years of Psychiatric Hospitalization

OBJECTIVE

As the number of older adults in the United States continues to grow, the population of older adults with severe mental illness in institutional settings (OASIS) is expected to place a significant demand on healthcare resources. This study presents an update to research regarding the clinical characteristics of OASIS inpatients with histories of extensive hospitalization through the use of a newly developed psychiatric measure: the Clinician-Rated Dimension of Psychosis Symptom Severity.

METHODS

We investigated an OASIS sample (N = 55) with an average of nearly 30 continuous years of hospitalization at a forensic state psychiatric hospital.

RESULTS

The average OASIS patient exhibited the most prominent psychiatric symptoms via delusions and negative symptoms, received psychotropic medications at substantially higher doses than recommended therapeutic levels, rarely committed acts of institutional violence (IV), and performed more than two standard deviations below the normative mean on cognitive testing. More severe hallucination symptoms were associated with higher psychotropic medication dosage, and more severe depressive symptoms were associated with more IV incidents. OASIS inpatients performed moderately worse than general psychiatric inpatients in the areas of overall cognition, immediate memory, and delayed memory; older age was associated with poorer language and attention. No psychiatric or cognitive factors predicted IV incidents.

CONCLUSION

These results highlight the continued importance of understanding the psychiatric, forensic, and cognitive factors associated with aging in an institutional setting and how these factors among OASIS inpatients may vary from general psychiatric inpatients.

Structural Magnetic Resonance Imaging Correlates of Aggression in Psychosis: A Systematic Review and Effect Size Analysis

Background: Aggression in psychoses is of high clinical importance, and volumetric MRI techniques have been used to explore its structural brain correlates. Methods: We conducted a systematic review searching EMBASE, ScienceDirect, and PsycINFO through September 2017 using thesauri representing aggression, psychosis, and brain imaging. We calculated effect sizes for each study and mean Hedge's g for whole brain (WB) volume. Methodological quality was established using the PRISMA checklist (PROSPERO: CRD42014014461). Results: Our sample consisted of 12 studies with 470 patients and 155 healthy controls (HC). After subtracting subjects due to cohort overlaps, 314 patients and 96 HC remained. Qualitative analyses showed lower volumes of WB, prefrontal regions, temporal lobe, hippocampus, thalamus and cerebellum, and higher volumes of lateral ventricles, amygdala, and putamen in violent vs. non-violent people with schizophrenia. In quantitative analyses, violent persons with schizophrenia exhibited a significantly lower WB volume than HC (p = 0.004), and also lower than non-violent persons with schizophrenia (p = 0.007). Conclusions: We reviewed evidence for differences in brain volume correlates of aggression in persons with schizophrenia. Our results point toward a reduced whole brain volume in violent as opposed to non-violent persons with schizophrenia. However, considerable sample overlap in the literature, lack of reporting of potential confounding variables, and missing research on affective psychoses limit our explanatory power. To permit stronger conclusions, further studies evaluating structural correlates of aggression in psychotic disorders are needed.

Functional Neuroimaging Correlates of Aggression in Psychosis: A Systematic Review With Recommendations for Future Research

Background and methods: Aggression in psychosis is clinically important. We systematically compiled the evidence on functional correlates of aggression in psychosis searching PubMed, EMBASE, ScienceDirect, and PsycINFO until September 2017. We included studies reporting functional brain imaging correlates of aggression comparing: (1) affective or non-affective psychosis groups with a history of violence or with aggression operationalized using questionnaires, (2) affective or non-affective psychosis groups with a history of violence or with aggression operationalized using questionnaires to controls, (3) affective or non-affective psychosis groups with a history of violence or with aggression operationalized using questionnaires to controls with diagnoses other than affective or non-affective psychoses. We applied no language restriction and required patients to have a DSM or ICD diagnosis of affective or non-affective psychosis. Results: Our sample consisted of 12 studies with 334 patients and 113 controls. During n-back tasks, violent (VS) as opposed to non-violent persons with schizophrenia (NVS) hypoactivated their inferior parietal lobe. When anticipating shock, VS vs. NVS hyperactivated their medial prefrontal gyrus, cuneus, middle temporal gyrus, and middle occipital gyrus. When viewing negative emotional pictures, VS vs. NVS hyperactivated the middle frontal gyrus, inferior frontal gyrus, anterior cingulate, lingual gyrus, precentral gyrus, globus pallidus, mid-cingulate, and precuneus. Limitations: Due to the small number of available studies, sample overlap, and insufficient reporting of relevant moderators we could not conduct a meta-analysis. Conclusions: We found non-systematic functional correlates of aggression in schizophrenia. Only few studies using varied paradigms and often overlapping samples have been conducted. There have been no attempts to replicate any of the observed findings in the published literature. Focusing on future directions, we recommend that authors adhere to clear definitions of aggression, measurements of psychopathology, comorbidities, and medication. In particular, replication studies would allow for a better synthesis of the findings. PROSPERO Registration Number: CRD42016048579.

Murder and psychosis: Neuropsychological profiles of homicide offenders with schizophrenia

BACKGROUND

Neurocognitive dysfunction, a core feature of schizophrenia, is thought to contribute to the impulsive violent aggression manifested by some individuals with schizophrenia, but not enough is known about how homicidal individuals with schizophrenia perform on neuropsychological measures.

AIMS

The primary aim of our study was to describe the neuropsychological profiles of homicide offenders with schizophrenia. Supplementary analyses compared the criminal, psychiatric and neuropsychological features of schizophrenic homicide offenders with and without God/Satan/demon-themed psychotic symptoms.

METHODS

Twenty-five men and women diagnosed with schizophrenia who had killed another person - 21 convicted of first-degree murder and 4 found not guilty by reason of insanity - completed neuropsychological testing during forensic evaluations.

RESULTS

The sample was characterised by extensive neurocognitive impairments, involving executive dysfunction (60%), memory dysfunction (68%) and attentional dysfunction (50%), although those with God/Satan/demon-themed psychotic symptoms performed better than those with nonreligious psychotic content.

CONCLUSIONS

Our findings indicate that impaired cognition may play an important role in the commission of homicide by individuals with schizophrenia. A subgroup with God/Satan/demon delusions seem sufficiently less impaired that they might be able to engage in metacognitive treatment approaches, aimed at changing their relationship to their psychotic symptoms, thus reducing the perception of power and omnipotence of hallucinated voices and increasing their safety. Copyright © 2016 John Wiley & Sons, Ltd.

Neuropsychological Impairment and Its Association with Violence Risk in Japanese Forensic Psychiatric Patients: A Case-Control Study

Background

In Japan, the legislation directing treatment of offenders with psychiatric disorders was enacted in 2005. Neuropsychological impairment is highly related to functional outcomes in patients with psychiatric disorders, and several studies have suggested an association between neuropsychological impairment and violent behaviors. However, there have been no studies of neuropsychological impairment in forensic patients covered by the Japanese legislation. This study is designed to examine the neuropsychological characteristics of forensic patients in comparison to healthy controls and to assess the relationship between neuropsychological impairment and violence risk.

Methods

Seventy-one forensic patients with psychiatric disorders and 54 healthy controls (matched by age, gender, and education) were enrolled. The CogState Battery (CSB) consisting of eight cognitive domains, the Iowa Gambling Task (IGT) to test emotion-based decision making, and psychological measures of violence risk including psychopathy were used.

Results

Forensic patients exhibited poorer performances on all CSB subtests and the IGT than controls. For each group, partial correlational analyses indicated that poor IGT performance was related to psychopathy, especially antisocial behavior. In forensic patients, the CSB composite score was associated with risk factors for future violent behavior, including stress and noncompliance with remediation attempts.

Conclusion

Forensic patients with psychiatric disorders exhibit a wide range of neuropsychological impairments, and these findings suggest that neuropsychological impairment may increase the risk of violent behavior. Therefore, the treatment of neuropsychological impairment in forensic patients with psychiatric disorders is necessary to improve functional outcomes as well as to prevent violence.

Anterior cingulate hyperactivations during negative emotion processing among men with schizophrenia and a history of violent behavior

BACKGROUND

Evidence suggests a 2.1-4.6 times increase in the risk of violent behavior in schizophrenia compared to the general population. Current theories propose that the processing of negative emotions is defective in violent individuals and that dysfunctions within the neural circuits involved in emotion processing are implicated in violence. Although schizophrenia patients show enhanced sensitivity to negative stimuli, there are only few functional neuroimaging studies that have examined emotion processing among men with schizophrenia and a history of violence.

OBJECTIVE

The present study aimed to identify the brain regions with greater neurofunctional alterations, as detected by functional magnetic resonance imaging during an emotion processing task, of men with schizophrenia who had engaged in violent behavior compared with those who had not.

METHODS

Sixty men were studied; 20 with schizophrenia and a history of violence, 19 with schizophrenia and no violence, and 21 healthy men were scanned while viewing positive, negative, and neutral images.

RESULTS

Negative images elicited hyperactivations in the anterior cingulate cortex (ACC), left and right lingual gyrus, and the left precentral gyrus in violent men with schizophrenia, compared to nonviolent men with schizophrenia and healthy men. Neutral images elicited hyperactivations in the right and left middle occipital gyrus, left lingual gyrus, and the left fusiform gyrus in violent men with schizophrenia, compared to the other two groups.

DISCUSSION

Violent men with schizophrenia displayed specific increases in ACC in response to negative images. Given the role of the ACC in information integration, these results indicate a specific dysfunction in the processing of negative emotions that may trigger violent behavior in men with schizophrenia.

A randomized study of cognitive remediation for forensic and mental health patients with schizophrenia

Cognitive remediation has proven efficacy for improving neurocognition in people with schizophrenia. The current study evaluated the benefits of cognitive remediation on neurocognition, functioning, psychotic symptoms, and aggression in a sample of forensic and mental health patients. Care recipients with schizophrenia or schizoaffective disorder (N = 78) receiving services in the forensic and mental health units of a state hospital were randomized to participate in cognitive remediation versus computer games control activities. Participants' neurocognition, functional capacity, experiential recovery, psychotic symptoms, and aggression incidents were assessed at baseline and posttreatment. Cognitive remediation was associated with improvements in several neurocognitive domains and circumscribed domains of functional capacity. People assigned to cognitive remediation experiences greater reductions in negative symptoms, agitation/excitement, and verbal and physical aggression. In addition to improving neurocognition in long-term hospitalized forensic and mental health patients, cognitive remediation may enhance efforts at reducing negative symptoms, emotion dysregulation, and aggression incidents. Forensic settings may represent a new frontier for the clinical dissemination of cognitive remediation.

Prospective cohort study of the relationship between neuro-cognition, social cognition and violence in forensic patients with schizophrenia and schizoaffective disorder

BACKGROUND

There is a broad literature suggesting that cognitive difficulties are associated with violence across a variety of groups. Although neurocognitive and social cognitive deficits are core features of schizophrenia, evidence of a relationship between cognitive impairments and violence within this patient population has been mixed.

METHODS

We prospectively examined whether neurocognition and social cognition predicted inpatient violence amongst patients with schizophrenia and schizoaffective disorder (n = 89; 10 violent) over a 12 month period. Neurocognition and social cognition were assessed using the MATRICS Consensus Cognitive Battery (MCCB).

RESULTS

Using multivariate analysis neurocognition and social cognition variables could account for 34 % of the variance in violent incidents after controlling for age and gender. Scores on a social cognitive reasoning task (MSCEIT) were significantly lower for the violent compared to nonviolent group and produced the largest effect size. Mediation analysis showed that the relationship between neurocognition and violence was completely mediated by each of the following variables independently: social cognition (MSCEIT), symptoms (PANSS Total Score), social functioning (SOFAS) and violence proneness (HCR-20 Total Score). There was no evidence of a serial pathway between neurocognition and multiple mediators and violence, and only social cognition and violence proneness operated in parallel as significant mediators accounting for 46 % of the variance in violent incidents. There was also no evidence that neurocogniton mediated the relationship between any of these variables and violence.

CONCLUSIONS

Of all the predictors examined, neurocognition was the only variable whose effects on violence consistently showed evidence of mediation. Neurocognition operates as a distal risk factor mediated through more proximal factors. Social cognition in contrast has a direct effect on violence independent of neurocognition, violence proneness and symptom severity. The neurocognitive impairment experienced by patients with schizophrenia spectrum disorders may create the foundation for the emergence of a range of risk factors for violence including deficits in social reasoning, symptoms, social functioning, and HCR-20 risk items, which in turn are causally related to violence.

Neurocognitive features in male patients with schizophrenia exhibiting serious violence: a case control study

BACKGROUND

The relationship between violence and neurocognitive function in schizophrenia is unclear. We examined the backgrounds and neurocognitive functions of violent and nonviolent patients with schizophrenia to identify factors associated with serious violence.

METHODS

Thirty male patients with schizophrenia who were hospitalized after committing serious violent acts were compared with 24 hospitalized male patients with schizophrenia and no history of violence. We evaluated psychiatric symptoms using the Positive and Negative Syndrome Scale (PANSS) and neurocognitive functions using the Brief Assessment of Cognition in Schizophrenia (BACS)-Japanese version.

RESULTS

Repeated-measures analyses of variance on BACS subcomponents z-scores showed that the violent and control groups had different neuropsychological profiles at trend level (p = 0.095). Post hoc analyses of variance indicated that the violent group had significantly better working memory and executive function than the control group. In post hoc ANOVAs also controlling for the effect of the presence of substance abuse on cognitive function, violent or nonviolent group had a significant main effect on executive function but not on working memory.

CONCLUSIONS

Patient with violent or non-violent schizophrenia have distinct neuropsychological profiles. These results may help develop improved psychosocial treatments.

Moral cognition in schizophrenia

INTRODUCTION

Disordered moral behaviour and understanding of moral rules were described early in the literature on schizophrenia; however, moral cognition has received scant attention in spite of a large literature focused on social cognitive impairments and violent behaviour in schizophrenia.

METHODS

We conducted a narrative synthesis of the literature on violence, moral judgement and schizophrenia.

RESULTS

Initial empirical research into moral cognition in schizophrenia did not fully account for the basic- and social-cognitive deficits now known to characterise schizophrenia. Importantly, research into moral cognition in autism and psychopathy, disorders in part characterised by social cognitive impairments indicates subtle patterns of difference to the moral cognition of control participants. Recent neuroeconomic studies of moral cognition in schizophrenia have indicated that individuals with schizophrenia display subtle dysfunction in their fairness-related behaviours, but not in their propensity to engage in altruistic punishment.

CONCLUSIONS

Further research has the potential to broaden our understanding of what is intact and what is impaired in moral cognition in schizophrenia and also to inform our theories of the structures subserving moral judgement in the general population. Furthermore, a more thorough understanding of moral cognitive impairments in schizophrenia may have implications for both legal process and psychosocial rehabilitation.

Violence among people with schizophrenia: phenotypes and neurobiology

People with schizophrenia are at increased risk, as compared to the general population, to acquire convictions for violent crimes and homicide. They also show elevated levels of aggressive behaviour. While psychotic symptoms explain aggressive behaviour that is common during acute episodes, they do not explain such behaviour at other stages of illness or prior to illness onset. Three distinct phenotypes have been identified: individuals with a childhood onset of conduct disorder who display antisocial and aggressive behaviour both before and after schizophrenia onset; individuals with no history of conduct problems who begin engaging in aggressive behaviour as illness onsets; and individuals who after many years of illness engage in a severe physical assault. Little is known about the aetiology of the three types of offenders and about the neural mechanisms that initiate and maintain these behaviours. We hypothesize that schizophrenia preceded by conduct disorder is associated with a combination of genes conferring vulnerability for both disorders and altering the effects of environmental factors on the brain, and thereby, with a distinct pattern of neural development. Some evidence is available to support this hypothesis. By contrast, offending among adults with schizophrenia who have no history of such behaviour prior to illness may result from the changes in the brain that occur as illness onsets, and that are further altered by comorbid conditions such as substance misuse, or by the progressive changes in the brain through adulthood that may result from the illness and from the use of antipsychotic medications.

Neurocognitive vulnerability: suicidal and homicidal behaviours in patients with schizophrenia

OBJECTIVE

Schizophrenia is associated with an increase in the risk of both homicide and suicide. The objectives of this study were to systematically review all published articles that examined the relation between neurocognitive deficits and suicidal or homicidal behaviours in schizophrenia, and to identify vulnerabilities in suicidal and homicidal behaviour that may share a common pathway in schizophrenia.

METHODS

A systematic review of the literature was performed using MEDLINE to include all studies published up to August 31, 2012.

RESULTS

Among the 1760 studies, 7 neuropsychological and 12 brain imaging studies met the selection criteria and were included in the final analysis. The neuropsychological and functional neuroimaging studies were inconclusive. The structural imaging studies reported various alterations in patients with schizophrenia and a history of homicidal behaviour, including: reduced inferior frontal and temporal cortices, increased mediodorsal white matter, and increased amygdala volumes. Patients with a history of suicidal acts showed volumetric reductions in left orbitofrontal and superior temporal cortices, while right amygdala volume was increased, though, these findings have rarely been replicated. Finally, no study has directly compared neurocognitive markers of suicidal and homicidal risk.

CONCLUSION

These results suggest that brain alterations, in addition to those associated with schizophrenia, may predispose some patients to a higher risk of homicide or suicide in particular circumstances. Moreover, some of these alterations may be shared between homicidal and suicidal patients. However, owing to several limitations, including the small number of available studies, no firm conclusions can be drawn and further investigations are necessary.

Structural brain alterations associated with schizophrenia preceded by conduct disorder: a common and distinct subtype of schizophrenia?

Conduct disorder (CD) prior to age 15 is a precursor of schizophrenia in a minority of cases and is associated with violent behavior through adulthood, after taking account of substance misuse. The present study used structural magnetic imaging to examine gray matter (GM) volumes among 27 men with schizophrenia preceded by CD (SZ+CD), 23 men with schizophrenia but without CD (SZ-CD), 27 men with CD only (CD), and 25 healthy (H) men. The groups with schizophrenia were similar in terms of age of onset and duration of illness, levels of psychotic symptoms, and medication. The 2 groups with CD were similar as to number of CD symptoms, lifelong aggressive behavior, and number of criminal convictions. Men with SZ+CD, relative to those with SZ-CD, displayed (1) increased GM volumes in the hypothalamus, the left putamen, the right cuneus/precuneus, and the right inferior parietal cortex after controlling for age, alcohol, and drug misuse and (2) decreased GM volumes in the inferior frontal region. Men with SZ+CD (relative to the SZ-CD group) and CD (relative to the H group) displayed increased GM volumes of the hypothalamus and the inferior and superior parietal lobes, which were not associated with substance misuse. Aggressive behavior, both prior to age 15 and lifetime tendency, was positively correlated with the GM volume of the hypothalamus. Thus, among males, SZ+CD represents a distinct subtype of schizophrenia. Although differences in behavior emerge in childhood and remain stable through adulthood, further research is needed to determine whether the differences in GM volumes result from abnormal neural development distinct from that of other males developing schizophrenia.

Factors predicting hostility in outpatients with schizophrenia: 36-month results from the SOHO study

This analysis explored the prevalence, incidence, and predictors of hostility in the European Schizophrenia Outpatient Health Outcomes (EU-SOHO) study. Data were collected at baseline and up to 36 months on the presence of hostility, clinical course and severity, medication compliance, side effects, substance/alcohol abuse, and being a crime survivor. Regression models were fitted to test the association between predictors and the presence of hostility. Hostility prevalence in the 6 months before baseline was 27.9%, and the incidence at 3 years was 14.0%. Variables related to hostility during follow-up were age, male sex, alcohol/substance abuse, tardive dyskinesia, extrapyramidal symptoms, cognitive impairment, noncompliance, and hospitalization. Being a crime survivor, being married, not living independently, and not being in paid employment were associated with hostility at baseline. Clinical and social variables are related to hostility in schizophrenia. Extrapyramidal symptoms and tardive dyskinesia, alcohol/substance abuse, cognitive impairment, medication noncompliance, and hospitalizations are predictors of future hostility.

Executive functioning deficits and childhood trauma in juvenile violent offenders in China

A large body of evidence indicates that violent offenders have executive functioning deficits. However, previous studies have not considered childhood trauma, which is likely to influence the executive functioning of violent offenders. The aim of the present study was to compare the difference of executive functioning among juvenile violent offenders, with non-violent offenders and normal controls, and then to analyse whether executive functioning was affected independently of childhood trauma. In addition to using a battery of tests assessing executive functioning including the Intra/Extradimensional Shift Test(IED), the Stockings of Cambridge Test (SOC), and the Spatial Working Memory Test (SWM) from the Cambridge Automated Neuropsychological Testing Battery (CANTAB), the short form of the Chinese Revision of the Wechsler Adult Intelligence Scale (WAIS-RC) and Childhood Trauma Questionnaire-28 item Short Form (CTQ) were also used among 107 violent offenders, 107 non-violent offenders and 107 normal controls. Our results showed that both offender groups obtained significantly lower estimated Intelligence Quotient (IQ) scores and experienced more childhood trauma than did normal controls. Violent offenders showed impaired executive functioning on tasks of attention set-shifting, working memory and planning. Finally, spatial working memory (SWM) deficits, particularly SWM strategy scores, may be associated with childhood trauma.

Smaller right amygdala in Caucasian alcohol-dependent male patients with a history of intimate partner violence: a volumetric imaging study

Studies have shown that various brain structure abnormalities are associated with chronic alcohol abuse and impulsive aggression. However, few imaging studies have focused on violent individuals with a diagnosis of alcohol dependence. The present study used volumetric magnetic resonance imaging (MRI) to compare the volumes of different structural components of prefrontal cortex and six subcortical structures in perpetrators of intimate partner violence with alcohol dependence (IPV-ADs), non-violent alcohol-dependent patients (non-violent ADs) and healthy controls (HCs). Caucasian men (n = 54), ages 24-55, who had participated in National Institutes of Alcohol Abuse and Alcoholism treatment programs, were grouped together as IPV-ADs (n = 27), non-violent ADs (n = 14) and HCs (n = 13). The MRI scan was performed at least 3 weeks from the participant's last alcohol use. T1-weighted images were used to measure the volumes of intracranial space, gray and white matter, orbitofrontal cortex, medial prefrontal cortex, lateral prefrontal cortex, and six subcortical structures. Results revealed that IPV-ADs, compared with non-violent ADs and HCs, had a significant volume reduction in the right amygdala. No significant volumetric difference was found in other structures. This finding suggests that structural deficits in the right amygdala may underlie impulsive types of aggression often seen in alcohol-dependent patients with a history of IPV. It adds to a growing literature suggesting that there are fundamental differences between alcohol-dependent patients with and without IPV.

Symptoms associated with victimization in patients with schizophrenia and related disorders

Background

Patients with psychoses have an increased risk of becoming victims of violence. Previous studies have suggested that higher symptom levels are associated with a raised risk of becoming a victim of physical violence. There has been, however, no evidence on the type of symptoms that are linked with an increased risk of recent victimization.

Methods

Data was taken from two studies on involuntarily admitted patients, one national study in England and an international one in six other European countries. In the week following admission, trained interviewers asked patients whether they had been victims of physical violence in the year prior to admission, and assessed symptoms on the Brief Psychiatric Rating Scale (BPRS). Only patients with a diagnosis of schizophrenia or related disorders (ICD-10 F20–29) were included in the analysis which was conducted separately for the two samples. Symptom levels assessed on the BPRS subscales were tested as predictors of victimization. Univariable and multivariable logistic regression models were fitted to estimate adjusted odds ratios.

Results

Data from 383 patients in the English sample and 543 patients in the European sample was analysed. Rates of victimization were 37.8% and 28.0% respectively. In multivariable models, the BPRS manic subscale was significantly associated with victimization in both samples.

Conclusions

Higher levels of manic symptoms indicate a raised risk of being a victim of violence in involuntary patients with schizophrenia and related disorders. This might be explained by higher activity levels, impaired judgement or poorer self-control in patients with manic symptoms. Such symptoms should be specifically considered in risk assessments.

Neuroimaging and neurocognitive correlates of aggression and violence in schizophrenia

Individuals diagnosed with major mental disorders such as schizophrenia are more likely to have engaged in violent behavior than mentally healthy members of the same communities. Although aggressive acts can have numerous causes, research about the underlying neurobiology of violence and aggression in schizophrenia can lead to a better understanding of the heterogeneous nature of that behavior and can assist in developing new treatment strategies. The purpose of this paper is to review the recent literature and discuss some of the neurobiological correlates of aggression and violence. The focus will be on schizophrenia, and the results of neuroimaging and neuropsychological studies that have directly investigated brain functioning and/or structure in aggressive and violent samples will be discussed as well as other domains that might predispose to aggression and violence such as deficits in responding to the emotional expressions of others, impulsivity, and psychopathological symptoms. Finally gender differences regarding aggression and violence are discussed. In this context several methodological and conceptional issues that limited the comparison of these studies will be addressed.

Structured assessment of violence risk in schizophrenia and other psychiatric disorders: a systematic review of the validity, reliability, and item content of 10 available instruments

OBJECTIVES

To undertake a systematic review on structured violence risk assessment tools in individuals with schizophrenia.

METHODS

A systematic search was conducted from 1990 to 2011 to identify violence risk assessment tools and studies examining their predictive validity. Item content of the identified instruments was analyzed, and areas under the curve (AUC) from the studies were extracted. In addition, an 11-item checklist was developed to assess the utility and psychometric properties of these tools.

RESULTS

Ten risk assessment tools designed to predict community violence in psychiatric patients were identified, but only 2 studies reporting predictive validity estimates in patients with schizophrenia were found (median AUC = 0.69; interquartile range = 0.60-0.77). When inclusion criteria was broadened to include studies measuring accuracy for any diagnostic group, mixed evidence of predictive validity was found, with median AUCs ranging from 0.62 to 0.85 depending on the population. Item content included mostly clinical, sociodemographic, and criminal history factors. As only 1 tool included a neurobiological item, a structured review of brain-based and cognitive risk factors for violence was included, and 3 clusters (neurocognitive ability, neurocognitive awareness, and attitudinal cognition) were identified.

CONCLUSIONS

While a number of violence risk assessment tools exist that can be used to predict the likelihood of community violence in psychiatric patients, there is currently little direct evidence for their utility in individuals with schizophrenia. In addition, there is large variation in item content between instruments, and further research is necessary to determine whether the inclusion of alternative factors could improve risk assessment.

Neuroimaging correlates of aggression in schizophrenia: an update

PURPOSE OF REVIEW

Aggression in schizophrenia is associated with poor treatment outcomes, hospital admissions, and stigmatization of patients. As such it represents an important public health issue. This article reviews recent neuroimaging studies of aggression in schizophrenia, focusing on PET/single photon emission computed tomography and MRI methods.

RECENT FINDINGS

The neuroimaging literature on aggression in schizophrenia is in a period of development. This is attributable in part to the heterogeneous nature and basis of that aggression. Radiological methods have consistently shown reduced activity in frontal and temporal regions. MRI brain volumetric studies have been less consistent, with some studies finding increased volumes of inferior frontal structures, and others finding reduced volumes in aggressive individuals with schizophrenia. Functional MRI studies have also had inconsistent results, with most finding reduced activity in inferior frontal and temporal regions, but some also finding increased activity in other regions. Some studies have made a distinction between types of aggression in schizophrenia in the context of antisocial traits, and this appears to be useful in understanding the neuroimaging literature.

SUMMARY

Frontal and temporal abnormalities appear to be a consistent feature of aggression in schizophrenia, but their precise nature likely differs because of the heterogeneous nature of that behavior.

Criminal offending and distinguishing features of offenders among persons experiencing a first episode of psychosis

AIMS

Persons with severe mental illness (SMI) are at increased risk of criminal offending, particularly violent offending, as compared with the general population. Most offenders with SMI acquire convictions prior to contact with mental health services. This study examined offending among 301 individuals experiencing their first episode of psychosis.

METHODS

Patients provided information on sociodemographic and clinical variables and completed a neurological soft sign examination and neuropsychological tests. Additional information was extracted from clinical files and official criminal records.

RESULTS

The results show that 33.9% of the men and 10.0% of the women had a record of criminal convictions, and 19.9% of the men and 4.6% of the women had been convicted of at least one violent crime. Proportionately more male and female patients than men and women in the general UK population had prior convictions for violent crimes. In a multivariate model including background and clinical variables, only one variable distinguished the male offenders. African-Caribbean ethnicity was associated with a threefold increase in the odds of offending (odds ratio=3.84, 95% confidence interval 1.03-14.37). Offenders, as compared with non-offenders, obtained significantly lower premorbid and current intelligence quotient scores and similar scores on tests of neurological soft signs, working memory and executive functions.

CONCLUSIONS

At contact with mental health services for a first episode of psychosis, significant numbers of patients have records of criminal convictions and thereby a high risk for future violent behaviour. These patients require specific interventions, in addition to medication, to reduce offending and aggressive behaviour.

Impulsivity and neural correlates of response inhibition in schizophrenia

BACKGROUND

The clinical picture of schizophrenia is frequently worsened by manifestations of impulsivity. However, the neural correlates of impulsivity in this disorder are poorly known. Although impulsivity has been related to disturbances of the neural processes underlying response inhibition, no studies have yet examined the relationship between these processes and psychometric measures of impulsivity in schizophrenia. This was the aim of the current investigation.

METHOD

Event-related functional magnetic resonance imaging in conjunction with a Go/NoGo task was employed to probe the neural activity associated with response inhibition in 26 patients with schizophrenia and 30 healthy comparison subjects. All participants also completed the Barratt Impulsiveness Scale - version 11 (BIS-11). Voxel-wise regression analyses were used to examine the relationship between the BIS-11 score and brain activation during response inhibition in each group.

RESULTS

Patients with schizophrenia were more impulsive than healthy subjects, as indicated by higher BIS-11 scores. Patients, but not healthy subjects, were found to display a positive correlation between these scores and cerebral activation associated with response inhibition. This correlation involves a unique cluster localized within the right ventrolateral prefrontal cortex (VLPFC), a key node of the brain network subserving response inhibition.

CONCLUSIONS

We evidenced in patients with schizophrenia that greater BIS-11 scores are associated with greater activation within the right VLPFC during response inhibition. This finding suggests that the efficiency of this brain region to process inhibitory control is reduced in the more impulsive patients.

Suicidal attempts and increased right amygdala volume in schizophrenia

Suicide is a major cause of death in schizophrenia. Neurobiological studies suggest that suicidality is associated with abnormal brain structure and connectivity in fronto-temporo-limbic regions. However, it is still unclear whether suicidality in schizophrenia is related to volumetric abnormalities in subcortical structures that play a key role in emotion regulation, aggression and impulse control. Therefore, we aimed to examine whether the volume of selected subcortical regions is associated with previous suicidal attempts and self-aggression in schizophrenia. For this cross-sectional study, we recruited 50 outpatients with schizophrenia and 50 healthy controls (HC) matched for age and gender. Fourteen patients had a history of one or more suicide attempts. Different forms of aggression were assessed using the Modified Overt Aggression Scale. All participants underwent structural MR imaging at 3 Tesla. Physical volumetric measures were calculated for the lateral ventricles, thalamus, hippocampus, amygdala, caudate, putamen, pallidum and accumbens using an automatic segmentation method on T1-weighted high-resolution (voxel size 1×1×1mm(3)) images. Multivariate and follow-up univariate ANOVAs revealed a selective increase in volume in the right amygdala of patients with a history of suicidality compared both to patients without such a history and HC. Moreover, in the entire patient group increased right amygdala volume was related to increased self-aggression. Our findings suggest that right amygdala hypertrophy may be a risk factor for suicide attempts in patients with schizophrenia and this could be relevant for suicide prevention.

Prefrontal cortex activity during response inhibition associated with excitement symptoms in schizophrenia

Previous fMRI studies of schizophrenia have shown a prefrontal abnormality during response inhibition. However, the association with the clinical symptoms in schizophrenia remains unclear. The aim of the present study was to clarify the association of psychotic symptoms with the prefrontal function during response inhibition in patients with schizophrenia. We evaluated the prefrontal activity during the Go/NoGo task in 14 patients with schizophrenia and age- and gender-matched 40 healthy controls using multi-channel near-infrared spectroscopy. We also examined the relationship between the prefrontal function during the Go/NoGo task and psychotic symptoms assessed by the PANSS five-factor model in patients with schizophrenia. Subjects in both groups performed well on the task, and the omission and commission error rates in the NoGo condition showed no statistically significant differences. The comparison of prefrontal activation between the Go condition and the NoGo condition in each group revealed that the healthy controls had a significant deactivation during the NoGo condition in the dorsolateral prefrontal cortex (DLPFC), and such changes were not shown in patients with schizophrenia. Furthermore, in patients with schizophrenia, the excitement score of the PANSS five-factor model was positively correlated with the activation in the right prefrontal cortex and frontopolar region. These results suggested that the abnormal prefrontal activity during simple inhibition of response would be associated with excitement symptoms in patients with schizophrenia.

Association among aggressiveness, neurocognitive function, and the Val66Met polymorphism of brain-derived neurotrophic factor gene in male schizophrenic patients

BACKGROUND

The aim of this study was to investigate the association among aggressive behavior, neuropsychological function, and the Val66Met functional polymorphism of brain-derived neurotrophic factor (BDNF) gene in male schizophrenic patients.

METHODS

We examined 51 male patients with schizophrenia who had committed homicide (ie, H-SCZ), 50 male patients with schizophrenia who had not committed homicide (ie, NH-SCZ), and 50 healthy male controls. Patients were evaluated using the Positive and Negative Syndrome Scale, Life History of Aggression, and the Overt Aggression Scale. In addition, patients were given neurocognitive function tests, including Korean-Wechsler Adult Intelligence Scale short form, the Korean version of the Rey Memory Test, the Stroop Test, and the Wisconsin Card Sorting Test. The Val66Met polymorphism of the BDNF gene was also genotyped in all schizophrenic patients.

RESULTS

We observed no significant difference between patients in the H-SCZ and NH-SCZ groups, with regard to Positive and Negative Syndrome Scale scores. Total Life History of Aggression (P < .01) and Overt Aggression Scale scores for the most severe episode (P < .01) or for the previous month (P < .05) were higher in the H-SCZ group than in the NH-SCZ group. There were no significant differences in the genotype distribution or allelic frequency of the Val66Met polymorphism between the schizophrenic groups. In addition, we observed no significant differences between H-SCZ and NH-SCZ groups with regard to performance on neuropsychological tests. The Met allele of the Val66Met polymorphism was associated with poor intelligence quotient, memory quotient), learning, and delayed recall in the H-SCZ group. However, genotype did not seem to influence neurocognitive function in schizophrenic patients who had committed homicide.

CONCLUSIONS

The neurocognitive tests used in our study were unable to distinguish between violent and nonviolent schizophrenic patients. Furthermore, the Val66Met polymorphism was not associated with aggressiveness in patients with schizophrenia.

Reduced hippocampal and parahippocampal volumes in murderers with schizophrenia

Evidence has accumulated to suggest that individuals with schizophrenia are at increased risk for violent offending. Furthermore, converging evidence suggests that abnormalities in the fronto-limbic system, including the prefrontal cortex, the hippocampus, and the parahippocampal gyrus, may contribute towards both neuropsychological disturbances in schizophrenia and violent behavior. Since the behavioral and clinical consequences of disturbed fronto-limbic circuitry appear to differ in schizophrenia and violence, it may be argued that patients with schizophrenia who exhibit violent behavior would demonstrate different structural abnormalities compared to their non-violent counterparts. However, the neurobiological basis underlying homicide offenders with schizophrenia remains unclear and little is known regarding the cross-cultural applicability of the findings. Using a 2 x 2 factorial design on a total Chinese sample of 92 males and females, we found reduced gray matter volume in the hippocampus and parahippocampal gyrus in murderers with schizophrenia, in the parahippocampal gyrus in murderers without schizophrenia, and in the prefrontal cortex in non-violent schizophrenia compared to normal controls. Results provide initial evidence demonstrating cross-cultural generalizability of prior fronto-limbic findings on violent schizophrenia. Future studies examining subtle morphological changes in frontal and limbic structures in association with clinical and behavioral characteristics may help further clarify the neurobiological basis of violent behavior.

Psychopathy and functional magnetic resonance imaging blood oxygenation level-dependent responses to emotional faces in violent patients with schizophrenia

BACKGROUND

Comorbidity between schizophrenia and psychopathy has been noted in violent patients in forensic settings. Both disorders are characterized by deficits in processing sad and fearful emotions, but there have been no imaging studies examining the impact of comorbid psychopathic traits on emotional information processing in violent patients with schizophrenia. We tested the hypothesis that violent patients with schizophrenia who had high psychopathy scores would show attenuated amygdala responses to emotional (particularly fearful) faces compared with those with low psychopathy scores.

METHODS

Twenty-four violent male patients with schizophrenia were categorized as high/low scorers based on the Psychopathy Checklist: Screening Version. Participants underwent functional magnetic resonance imaging during a block-designed implicit face affect processing task. In a region of interest approach, responses in the amygdala and prefrontal cortex were examined with contrasts between sad/fearful/angry/disgusted faces and neutral faces.

RESULTS

High psychopathy scorers exhibited reduced blood oxygenation level-dependent (BOLD) responses in the amygdala during exposure to fearful faces. Psychopathy scores, particularly the affective facets, correlated negatively with amygdala responses. The BOLD responses in the orbitofrontal cortex were negatively correlated with the lifestyle and antisocial facets of psychopathy during exposure to sad faces. Psychopathy scores were positively correlated with neural activation in amygdala and inferior prefrontal regions for disgust but negatively correlated for anger.

CONCLUSIONS

Patients with schizophrenia and high levels of psychopathic traits appear to have blunted amygdala responses to fearful faces. At a dimensional level, psychopathy subfacets show a differential relationship to functioning in amygdala-prefrontal circuitry.

[Homicide and major mental disorder: what are the social, clinical, and forensic differences between murderers with a major mental disorder and murderers without any mental disorder?]

OBJECTIVES

To establish the social, clinical, and forensic differences between murderers suffering from a major mental disorder and murderers without any psychiatric disorder and, in particular, to compare their respective records of psychiatric symptoms and their respective relationship with their victims.

METHOD

We studied 210 forensic examinations of murderers, the offences related to the murders, and the social and clinical information collected from psychiatric court reports on persons convicted of homicide. Firstly, we identified the socio-demographic, clinical and criminological profiles of 210 murderers from which were distinguished murderers with major mental disorder. Then, we compared the profiles of murderers suffering from a major mental disorder with those of murderers without any mental disease. In other words, we compared 37 persons affected with major mental disorder (schizophrenia, paranoiac delusional disorder, and affective disorder) with 73 persons without any mental disorder. We deliberately excluded subjects with personality disorder or abuse of/dependency on drugs, mental retardation or dementia.

RESULTS

With the exception of certain variables, murderers with major mental disorder have the same characteristics as others murderers: young man, living alone, with psychiatric and offence records and substance abuse. Murderers with major mental disorder are older (37.8 versus 31.7 years old) than perpretators without any mental disorder, and the former have a psychiatric record more often than the latter (81 versus 32.9%). In addition, contrary to the latter, the former show clinical symptoms of a psychopathological process. Depression, delusional and suicidal ideas are frequent among murderers with a major mental disorder, whereas the persons without mental disorder quarrel or have a row with their victim just before their crime. The victim was known to the perpetrator significantly more often in the major mental disorder group than in the no mental disorder group (94,6 versus 76,7%, p=0,008). The most major mental disorders' homicide was more likely to be against intimates than strangers. The application of the former article 64 or the present article 122-1 of the French Criminal Code are envisaged more often in the major mental disorder group than in the no mental disorder group.

CONCLUSION

The main difference between murderers with a major mental disorder and murderers without any mental disorder is the psychopathology of the morbid process which underlies the homicide. Impairment of judgment at the time of the crime should be taken into account. As a clinician, we should focus our attention on general risk factors of violence and homicide (male, young, underprivileged class, abuse of alcohol) and on more specific factors (mental disorder co-morbidities...). To these factors should be added the dynamic characteristics of the meeting of the protagonists.

Dysfunctional, but not functional, impulsivity is associated with a history of seriously violent behaviour and reduced orbitofrontal and hippocampal volumes in schizophrenia

Aggression and violent acts have been linked with impulsive responding. We investigated whether impulsive personality trait, especially suggestive of dysfunctional impulsivity (i.e. fast and inaccurate responding where this is non-optimal), is associated with a history of seriously violent behaviour and specific brain deficits in schizophrenia. Twenty-four male participants with schizophrenia, of whom 10 had a history of serious physical violence, and 14 healthy male participants were assessed on impulsiveness (dysfunctional impulsivity), venturesomeness (functional impulsivity), and empathy. All participants underwent magnetic resonance imaging. The results revealed that participants with schizophrenia and a history of violence showed elevated impulsiveness but had comparable scores on venturesomeness and empathy dimensions. Impulsiveness scores correlated negatively with reduced orbitofrontal grey matter volume in both the patient and healthy control groups, and with hippocampal volume in the patient group. Our findings suggest that dysfunctional, but not functional, impulsivity is elevated in patients with schizophrenia with a propensity for repetitive violence, and this in turn appears to be associated with reduce volumes of both the orbitofrontal cortex grey matter and the hippocampus. Violence risk prediction and management strategies in schizophrenia may benefit from including specific measures of dysfunctional impulsive traits.