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

Individual-level deviations from normative brain morphology in violence, psychosis, and psychopathy

Neuroimaging research has shown brain morphological abnormalities associated with violence and psychosis, but individual differences are substantial and results not consistent across studies. Normative modeling of brain MRI-features facilitates a systematic mapping of individual brain characteristics of complex phenotypes also in small samples but has not yet been applied to forensic psychiatry populations. We explored brain heterogeneity in persons with a history of severe violence with a comorbid schizophrenia spectrum disorder (SSD-V; n = 38), non-violent persons with schizophrenia spectrum disorders (SSD-NV; n = 138), persons with a history of severe violence without comorbid schizophrenia spectrum disorder (nonSSD-V; n = 20), and healthy non-violent participants (HC; n = 196) from lifetime normative trajectories of cortical thickness, surface area, and subcortical volumes. Normative models based on Freesurfer derived regions of interest from 58,836 individuals were used to investigate individual deviances, group differences, and associations to psychopathy traits. We found overall heterogeneous patterns of individual deviations from the norm, which were most prominent for regions within the collateral transverse sulcus, lingual gyrus, and cerebellum among SSD-V, a pattern that differed from SSD-NV (parieto-occipital and suborbital sulci), and nonSSD-V (paracentral and middle frontal regions). We found no significant associations to psychopathy traits. By applying normative modeling, we demonstrate heterogeneous patterns of brain morphometry deviations associated with violence and psychosis. While the results warrant replication, studies addressing individual brain deviations may contribute to improved understanding of the neurobiological underpinnings of comorbid violence and psychosis, which ultimately may have clinical impact on treatment and forensic psychiatric evaluations.

Altered Neural Activation in First Episode Psychosis Patients With Comorbid Conduct Disorder: A Pilot Investigation

Objective

Most individuals with psychosis do not perpetrate violence. However, conduct disorder (CD) increases the risk of violence in psychotic conditions. Because it is currently unknown whether the neural correlates of first-episode psychosis (FEP) differ when CD is present, we used functional magnetic resonance imaging (fMRI) during a Go/No-Go impulsivity paradigm to investigate. Based on previous research, we hypothesized that activation differences between FEP and FEP+CD would be found in the prefrontal cortex, cingulate cortex, and inferior parietal lobule.

Method

We scanned 51 male participants: 17 FEP, 16 FEP+CD, and 18 healthy controls with an average age of 24.2 years (range, 17-34 years). Whole-brain images were analyzed via a general linear model, and first-level contrast images were created comparing successful No-Go > Go trials. Paired t tests were conducted at the group level and included confound regressors for age, IQ, antipsychotic dose, psychotic symptoms, and framewise displacement. A voxel-based Z-score threshold of Z > 3.1 (p < 0.001, uncorrected) and a cluster-level extent threshold of p <0.01, corrected, was considered significant.

Results

Successful response inhibition elicited hyperactivation in FEP+CD vs FEP in the cingulate gyrus; regions of the PFC, including right middle frontal gyrus (RMFG); bilateral inferior parietal lobule; temporal gyrus; and cerebellum (p values ranged from 1.11E-08 to 0.0031). There was no region in which activation was greater in FEP > FEP+CD.

Conclusion

These preliminary results tentatively suggest that brain regions subserving response inhibition may be altered when CD is comorbid with FEP.

What do we know now about evidence-based treatment for psychosis and aggressive behaviour or criminality that we did not know when community care was implemented?

PURPOSE

Community care replaced institutional care for people with psychosis without guidance about what constituted effective treatment. In a Swedish birth cohort, many of those who developed schizophrenia or bipolar disorder as community care was being implemented were subsequently convicted of violent and non-violent crimes. Studies from other countries that were implementing community care at this time also reported elevated proportions of patients acquiring criminal convictions. Since community care was first implemented, much has been learned about factors that promote and treatments that limit aggressive/antisocial behaviour/criminality (AABC) among people with psychosis. Without the benefit of this knowledge, did mental health policy and practices that were in place as the asylums were closed inadvertently contribute to criminality?

MATERIAL AND METHODS

This article provides a narrative review of current evidence of effective treatments and management strategies to reduce AABC among patients with psychosis.

RESULTS

Reductions in AABC are associated with stable contact with psychiatric services, second-generation antipsychotic medication, clozapine for patients with schizophrenia and elevated levels of hostility and/or a history of childhood conduct disorder, abstinence from substances, avoidance of trauma, and constant monitoring of both illness symptoms and AABC.

CONCLUSIONS

Failure to adopt evidence-based practices allows the problem of AABC to persist, prevents patients from experiencing independent, safe, community tenure, and puts those around them at risk. Many challenges remain, including implementing effective assessment and interventions at first-episode and convincing patients with antisocial attitudes and behaviours to participate in treatment programs to reduce AABC and to learn prosocial behaviours.

Large-scale meta-analyses and network analyses of neural substrates underlying human escalated aggression

Escalated aggression represents a frequent and severe form of violence, sometimes manifesting as antisocial behavior. Driven by the pressures of modern life, escalated aggression is of particular concern due to its rising prevalence and its destructive impact on both individual well-being and socioeconomic stability. However, a consistent neural circuitry underpinning it remains to be definitively identified. Here, we addressed this issue by comparing brain alterations between individuals with escalated aggression and those without such behavioral manifestations. We first conducted a meta-analysis to synthesize previous neuroimaging studies on functional and structural alterations of escalated aggression (325 experiments, 2997 foci, 16,529 subjects). Following-up network and functional decoding analyses were conducted to provide quantitative characterizations of the identified brain regions. Our results revealed that brain regions constantly involved in escalated aggression were localized in the subcortical network (amygdala and lateral orbitofrontal cortex) associated with emotion processing, the default mode network (dorsal medial prefrontal cortex and middle temporal gyrus) associated with mentalizing, and the salience network (anterior cingulate cortex and anterior insula) associated with cognitive control. These findings were further supported by additional meta-analyses on emotion processing, mentalizing, and cognitive control, all of which showed conjunction with the brain regions identified in the escalated aggression. Together, these findings advance the understanding of the risk biomarkers of escalated aggressive populations and refine theoretical models of human aggression.

Task-related brain activation associated with violence in patients with schizophrenia: A meta-analysis

This study investigates specific changes in brain function during cognitive and emotional tasks in patients with schizophrenia and a history of violence (VSCZ) compared with non-violent patients with schizophrenia and healthy controls. A comprehensive literature search was conducted at the Web of Science, Medline, and PubMed. Ten studies met the inclusion criteria. In which, eight studies compared brain activation between patients with VSCZ and non-violent patients with schizophrenia, and the former exhibited increased activation at the middle occipital gyrus and rectus compared with the latter. Seven studies compared brain activation between patients with VSCZ and controls, and the former exhibited increased activation at the anterior cingulate cortex, cerebellum VI region, lingual gyrus and fusiform. Subgroup analysis in five studies performing emotional tasks revealed that patients with VSCZ showed increased activation at the middle occipital gyrus compared with non-violent patients with schizophrenia. Our findings suggest that abnormal emotion perception and regulation significantly contribute to the increased risk of violence in patients with schizophrenia. Notably, the middle occipital gyrus and rectus emerge as key neurophysiological correlates associated with this phenomenon.

Hypothalamic Subunit Volumes in Schizophrenia and Bipolar Spectrum Disorders

BACKGROUND

The hypothalamus is central to many hormonal and autonomous nervous system pathways. Emerging evidence indicates that these pathways may be disrupted in schizophrenia and bipolar disorder. Yet, few studies have examined the volumes of hypothalamic subunits in these patient groups. We compared hypothalamic subunit volumes in individuals with psychotic disorders to healthy controls.

STUDY DESIGN

We included 344 patients with schizophrenia spectrum disorders (SCZ), 340 patients with bipolar disorders (BPD), and 684 age- and-sex-matched healthy controls (CTR). Total hypothalamus and five hypothalamic subunit volumes were extracted from T1-weighted magnetic resonance imaging (MRI) using an automated Bayesian segmentation method. Regression models, corrected for age, age2, sex, and segmentation-based intracranial volume (sbTIV), were used to examine diagnostic group differences, interactions with sex, and associations with clinical symptoms, antipsychotic medication, antidepressants and mood stabilizers.

STUDY RESULTS

SCZ had larger volumes in the left inferior tubular subunit and smaller right anterior-inferior, right anterior-superior, and right posterior hypothalamic subunits compared to CTR. BPD did not differ significantly from CTR for any hypothalamic subunit volume, however, there was a significant sex-by-diagnosis interaction. Analyses stratified by sex showed smaller right hypothalamus and right posterior subunit volumes in male patients, but not female patients, relative to same-sex controls. There was a significant association between BPD currently taking antipsychotic medication and the left inferior tubular subunits volumes.

CONCLUSIONS

Our results show regional-specific alterations in hypothalamus subunit volumes in individuals with SCZ, with relevance to HPA-axis dysregulation, circadian rhythm disruption, and cognition impairment.

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.

Neuroanatomical correlates of aggressiveness: a case-control voxel- and surface-based morphometric study

Aggression occurs across the population ranging on a symptom continuum. Most previous studies have used magnetic resonance imaging in clinical/forensic samples, which is associated with several confounding factors. The present study examined structural brain characteristics in two healthy samples differing only in their propensity for aggressive behavior. Voxel- and surface-based morphometry (SBM) analyses were performed on 29 male martial artists and 32 age-matched male controls. Martial artists had significantly increased mean gray matter volume in two frontal (left superior frontal gyrus and bilateral anterior cingulate cortex) and one parietal (bilateral posterior cingulate gyrus and precuneus) brain clusters compared to controls (whole brain: p < 0.001, cluster level: family-wise error (FWE)-corrected). SBM analyses revealed a trend for greater gyrification indices in martial artists compared to controls in the left lateral orbital frontal cortex and the left pars orbitalis (whole brain: p < 0.001, cluster level: FWE-corrected). The results indicate brain structural differences between martial artists and controls in frontal and parietal brain areas critical for emotion processing/inhibition of emotions as well as empathic processes. The present study highlights the importance of studying healthy subjects with a propensity for aggressive behavior in future structural MRI research on aggression.

DSM-5 conduct disorder and symptoms in youths at high risk of psychosis in Kenya with DSM-5 mental disorders and substance use: towards integrated management

Little is known about the prevalence of Conduct Disorder (CD) and symptoms of CD in high risk psychosis persons at both clinical and community populations in LMICs and in particular Kenya. This study aimed to document (1) the prevalence of CD diagnosis and symptoms in youth who screened positive for psychosis and (2) the associated mental disorders and substance use in the same cohort in LMIC. The sample size was 536 students who had screened positive on the Washington Early Recognition Center Affectivity and Psychosis (WERCAP) from a population of 9,742 high school, college and university students, but had not converted to a psychotic disorder. We collected data on socio-demographic characteristics and used the following tools: Economic indicators tool; the Diagnostic Interview Schedule (DIS) tool for DSM-5 diagnosis; World Health Organization (WHO) Alcohol, Smoking, and Substance Involvement Screening Test (ASSIST). Basic descriptive statistics, chi-square test, Fisher's exact test, Pearson correlation and Poisson regression were conducted. Five percent (5%) of the respondents met the criteria for DSM-5 CD. Indeterminate CD comprised 10.1%. Male gender, all substances except hallucinogens lifetime, obsessive compulsive disorder, psychosis, agoraphobia, social phobia, drug abuse/dependence, antisocial personality disorder, oppositional defiant disorder, suicidality, WERCAP screen for bipolar disorder and WERCAP screen for schizophrenia were significantly (p < 0.05) associated with CD. Deceitfulness or theft criteria symptoms showed that CD had no significant gender difference. Criteria symptoms in aggression to people and animals, destruction of property and serious violations of rules were more common among males. Our findings suggest the need to screen for and diagnose CD, mental disorders and substance use in high risk psychosis youths in Kenya. This will inform integrated management.

Hypothalamic volume in pedophilia with or without child sexual offense

The hypothalamus regulates sexual behavior and is simultaneously associated with aggression and violence. Consequently, this brain region is relevant in research of pedophilia and child sexual offenses (CSO). The distinction between these two phenomena is of great importance and was the object of consideration of this study. We analyzed exclusively men, including 73 pedophilic offenders who committed CSO, an equal number of people with pedophilia but without such offenses, and 133 non-pedophilic, non-offending subjects who formed the control group. All data were collected in a multicenter in vivo study and analyzed using a semi-automated segmentation algorithm for 3-Tesla magnetic resonance images. Men with pedophilia who committed CSO on average had a 47 mm3 smaller hypothalamus per side than people without committed CSO. This effect was driven by both the group of non-offending people with pedophilia and the control group. By contrast, the exploratory comparison of pedophilic persons without CSO with the control group showed no significant difference. The present study demonstrates a deviant hypothalamic structure as a neurobiological correlate of CSO in pedophiles, but not in people with pedophilia who have not committed CSO. Thus, it strengthens the argument to distinguish between sexual offending and paraphilic sexual preferences.

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.

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.

Female Forensic Patients May Be an Atypical Sub-type of Females Presenting Aggressive and Antisocial Behavior

The percentage of forensic psychiatric patients who are female varies from 5 to 13% in Europe, rises to 18% in England and Wales, and sits at 15% in Canada. Similarly, many fewer women than men are incarcerated in correctional facilities. While these statistics supposedly reflect less antisocial and aggressive behavior (AAB) among females than males, not all findings support this supposition. Data from prospective longitudinal studies show that aggressive and antisocial behavior onsets in childhood, and in a small group of females it remains stable across the life-span. Unlike similar males, few of these females are convicted of crimes. This article begins with a review of descriptive studies of females sentenced by criminal courts to treatment in forensic psychiatric hospitals and moves on to present evidence showing that most female AAB does not lead to criminal prosecution. Next, studies of female AAB are reviewed, noting that it onsets in early childhood and, that in a small group remains stable across the life-span. Subsequent sections of the article focus on the two most common mental disorders presented by female forensic patients, schizophrenia and borderline personality disorder, highlighting what is known about the sub-groups of women with these disorders who present AAB. The article concludes with recommendations for earlier identification by psychiatric services of women presenting mental disorders and AAB, treatments to reduce both the symptoms of their mental disorders and their life-long AAB, and the research that is needed in order to improve the effectiveness of these treatments. The real possibilities of prevention of the development of AAB, and even perhaps aspects of the mental disorders that plague female forensic patients, are described.

Could Expanding and Investing in First-Episode Psychosis Services Prevent Aggressive Behaviour and Violent Crime?

OBJECTIVE

Some persons developing, or presenting, schizophrenia engage in aggressive behaviour (AB) and/or criminal offending. Most of these individuals display AB prior to a first episode of psychosis (FEP). In fact, approximately one-third of FEP patients have a history of AB, some additionally display other antisocial behaviours (A+AB). The large majority of these individuals have presented conduct problems since childhood, benefit from clozapine, have extensive treatment needs, and are unlikely to comply with treatment. A smaller sub-group begin to engage in AB as illness onsets. A+AB persists, often for many years in spite of treatment-as-usual, until a victim is seriously harmed. This article proposes providing multi-component treatment programs at FEP in order to prevent aggressive and antisocial behaviours of persons with schizophrenia.

METHOD

Non-systematic reviews of epidemiological studies of AB among persons with schizophrenia, of the defining characteristics of sub-types of persons with schizophrenia who engage in AB and their responses to treatment, and of FEP service outcomes.

RESULTS

Studies have shown that mental health services that simultaneously target schizophrenia and aggressive behaviour are most effective both in reducing psychotic symptoms and aggressive behaviour. Evidence, although not abundant, suggests that a multi-component treatment program that would include the components recommended to treat schizophrenia and cognitive-behavioural interventions to reduce A+AB, and the other factors promoting A+AB such as substance misuse, victimisation, and poor recognition of emotions in the faces of others has the potential to effectively treat schizophrenia and reduce A+AB. Patients with a recent onset of AB would require few components of treatment, while those with prior conduct disorder would require all. Such a program of treatment would be long and intense.

CONCLUSIONS

Trials are needed to test the effectiveness of multi-component treatment programs targeting schizophrenia and A+AB at FEP. Studies are also necessary to determine whether providing such programs in hospitals and/or prisons, with long-term community after-care, and in some cases with court orders to participate in treatment, would enhance effectiveness. Whether investing at FEP would be cost-effective requires investigation.

Identifying subtypes of bipolar disorder based on clinical and neurobiological characteristics

The ability to classify patients with bipolar disorder (BD) is restricted by their heterogeneity, which limits the understanding of their neuropathology. Therefore, we aimed to investigate clinically discernible and neurobiologically distinguishable BD subtypes. T1-weighted and resting-state functional magnetic resonance images of 112 patients with BD were obtained, and patients were segregated according to diagnostic subtype (i.e., types I and II) and clinical patterns, including the number of episodes and hospitalizations and history of suicide and psychosis. For each clinical pattern, fewer and more occurrences subgroups and types I and II were classified through nested cross-validation for robust performance, with minimum redundancy and maximum relevance, in feature selection. To assess the proportion of variance in cognitive performance explained by the neurobiological markers, multiple linear regression between verbal memory and the selected features was conducted. Satisfactory performance (mean accuracy, 73.60%) in classifying patients with a high or low number of episodes was attained through functional connectivity, mostly from default-mode and motor networks. Moreover, these neurobiological markers explained 62% of the variance in verbal memory. The number of episodes is a potentially critical aspect of the neuropathology of BD. Neurobiological markers can help identify BD neuroprogression.

The Importance of Conduct Disorder in the Treatment of Violence in Schizophrenia: Efficacy of Clozapine Compared With Olanzapine and Haloperidol

OBJECTIVE

Treatment of violence in schizophrenia remains a challenging problem, especially in patients with conduct disorder. Previous clinical studies did not select patients on the basis of violence and did not focus on conduct disorder. This study is a head-to-head comparison of clozapine, olanzapine, and haloperidol in the treatment of violent schizophrenia patients with and without conduct disorder.

METHODS

Physically assaultive schizophrenia patients (N=99) were randomly assigned to receive clozapine, olanzapine, or haloperidol in a 12-week double-blind trial. They were characterized on the basis of the presence or absence of conduct disorder before age 15. Assaults were recorded; their frequency and severity were scored on the Modified Overt Aggression Scale. Psychiatric symptoms were evaluated through the Positive and Negative Syndrome Scale.

RESULTS

Patients with a history of conduct disorder had more frequent and severe assaults than those without conduct disorder during the 12-week trial. Clozapine was superior to haloperidol and olanzapine in reducing assaults; olanzapine was superior to haloperidol. Clozapine's greater antiaggressive efficacy over haloperidol was substantially more pronounced in patients with conduct disorder than in patients without conduct disorder. In patients with conduct disorder, clozapine was four times more likely than haloperidol to result in lower violence; in patients without conduct disorder, it was three times more likely to do so. Olanzapine's superiority over haloperidol was also more pronounced in patients with conduct disorder.

CONCLUSIONS

This study is the first to examine the effect of clozapine in violent schizophrenia patients with conduct disorder. When conduct disorder is present, clozapine is the optimal treatment.

The implications of hypothalamic abnormalities for schizophrenia

Until a few years ago, the hypothalamus was believed to play only a marginal role in schizophrenia pathophysiology. However, recent findings show that this rather small brain region involved in many pathways found disrupted-in schizophrenia. Gross anatomic abnormalities (volume changes of the third ventricle, the hypothalamus, and its individual nuclei) as well as alterations at the cellular level (circumscribed loss of neurons) can be observed. Further, increased or decreased expression of hypothalamic peptides such as oxytocin, vasopressin, several factors involved in the regulation of appetite and satiety, endogenous opiates, products of schizophrenia susceptibility genes as well as of enzymes involved in neurotransmitter and neuropeptide metabolism have been reported in schizophrenia and/or animal models of the disease. Remarkably, although profound disturbances of the hypothalamus-pituitary-adrenal axis, hypothalamus-pituitary-thyroid axis, and the hypothalamus-pituitary-gonadal axis are typical signs of schizophrenia, there is currently no evidence for alterations in the expression of hypothalamic-releasing and inhibiting factors that control these hormonal axes. Finally, the implications of hypothalamus for disease-related disturbances of the sleep-wakefulness cycle and neuroimmune dysfunctions in schizophrenia are outlined.

The Deficits of Individual Morphological Covariance Network Architecture in Schizophrenia Patients With and Without Violence

Background: Schizophrenia is associated with a significant increase in the risk of violence, which constitutes a public health concern and contributes to stigma associated with mental illness. Although previous studies revealed structural and functional abnormalities in individuals with violent schizophrenia (VSZ), the neural basis of psychotic violence remains controversial. Methods: In this study, high-resolution structural magnetic resonance imaging (MRI) data were acquired from 18 individuals with VSZ, 23 individuals with non-VSZ (NSZ), and 22 age- and sex-matched healthy controls (HCs). Whole-brain voxel-based morphology and individual morphological covariance networks were analysed to reveal differences in gray matter volume (GMV) and individual morphological covariance network topology. Relationships among abnormal GMV, network topology, and clinical assessments were examined using correlation analyses. Results: GMV in the hypothalamus gradually decreased from HCs and NSZ to VSZ and showed significant differences between all pairs of groups. Graph theory analyses revealed that morphological covariance networks of HCs, NSZ, and VSZ exhibited small worldness. Significant differences in network topology measures, including global efficiency, shortest path length, and nodal degree, were found. Furthermore, changes in GMV and network topology were closely related to clinical performance in the NSZ and VSZ groups. Conclusions: These findings revealed the important role of local structural abnormalities of the hypothalamus and global network topological impairments in the neuropathology of NSZ and VSZ, providing new insight into the neural basis of and markers for VSZ and NSZ to facilitate future accurate clinical diagnosis and targeted treatment.

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.

Volumetric Abnormalities in Violent Schizophrenia Patients on the General Psychiatric Ward

BACKGROUND

In recent years, neuroimaging has been used increasingly to explore the biological underpinnings of violence carried out by schizophrenia patients (SPs). Studies have focused mostly on patients with a history of carrying out severe physical assaults, or comorbid with substance abuse/personality disorder (SA/PD). As a result, participants were unrepresentative and the interpretation of brain-structure changes was confusing. Here, we concentrated on SPs on a general psychiatric ward with a history of relatively lower violence, and individuals comorbid with SA or PD were excluded. We expected to identify the characteristics of brain morphometry in this population, and to explore whether the morphometric changes were universal.

METHODS

Forty-eight violent schizophrenia patients (VSPs), twenty-seven non-VSPs (nVSPs) and 28 nonviolent healthy controls (HCs) were investigated. Voxel-based morphometry was used to evaluate the gray matter volume (GMV) of all study participants. Whole-brain analyses were used to reveal group effects and differences between any two groups. Correlation analyses were undertaken between significant brain regions and behavioral measurements in the VSP group.

RESULTS

Patients showed a significantly smaller GMV in widespread frontal, temporal, and limbic regions compared with HCs. No region was found in which the two patient groups had significantly larger volumes compared with that in HCs. A significant decrease in the GMV of the right fusiform gyrus was found in the VSP group compared with that in the nVSP group (p = 0.004), where the GMV of this region had a negative correlation with the Physical Aggression [subscale of the Modified Overt Aggression Scale (MOAS)] or Hostility score. The VSP group showed a trend of GMV decrease in the left middle temporal cortex compared with that in the nVSP group (p = 0.077). Negative correlation was also found between the GMV of left inferior temporal gyrus/left Superior frontal gyrus, medial and the Hostility score.

CONCLUSIONS

Our results provide initial evidence demonstrating the generalizability of GMV abnormalities in SPs engaged in varying levels of violence, even when SA or PD have not been implicated. GMV reduction was correlated with only the Physical Aggression subscale score of the MOAS, suggesting that this change in brain morphology may be dependent upon different types of violent actions.

Hippocampal subfield and amygdala nuclei volumes in schizophrenia patients with a history of violence

Schizophrenia (SCZ) is associated with an increased risk of violence compared to the general population. Previous studies have indicated smaller hippocampal and amygdala volumes in violent than non-violent psychotic patients^. However, little is known about volumetric differences at the subdivision level of these structures. In the present study, hippocampal subfields and amygdala nuclei volumes were estimated with FreeSurfer from 3 T MRI of SCZ patients with (SCZ-V, n = 24) and without (SCZ-NV, n = 51) a history of severe violence and 90 healthy controls (HC). Volumetric differences between groups were explored with a general linear model covarying for confounders, in addition to follow-up analyses in patient groups controlling for clinical characteristics such as antipsychotic medication, duration of illness and illicit substance use. SCZ-V had smaller total hippocampal volume and smaller CA1, HATA, fimbria, and molecular layer of DG volumes compared to HC. Total amygdala volume together with basal nucleus, accessory basal nucleus, CTA, and paralaminar nucleus volumes were smaller in SCZ-V compared to HC. In SCZ-NV, compared to HC, the observed smaller volumes were limited to basal and paralaminar nucleus. There were no significant differences in hippocampal subfield and amygdala nuclei volumes between SCZ-V and SCZ-NV. Follow-up analyses showed that the results in patient groups were not affected by clinical characteristics. The results suggest that smaller hippocampal subfield and amygdala nuclei volumes may be relevant to violence risk in SCZ. However, the neurobiological signature of violence in SCZ should be further investigated in larger cohorts.

Inferior frontal gyrus gray matter volume is associated with aggressive behavior in schizophrenia spectrum disorders

We aimed to assess potential gray matter (GM) alterations for aggressive patterns of behavior in a sample of in- and outpatients with schizophrenia spectrum disorders. Eighty-four patients previously participating in brain volumetric studies were included. Aggression was assessed using the Modified Overt Aggression Scales (MOAS) based upon review of clinical records of the hospital register. Multiple regression analyses for total MOAS and each MOAS subscale separately were conducted correcting for age, sex, history of addiction, chlorpromazine equivalents, illness duration, and total intracranial volume. Significant effects were reported in two cases; the total MOAS scores and MOAS verbal aggression scores were associated with GM volume in left inferior frontal gyrus. From the demographic/clinical characteristics, only the number of episodes correlated with the subscales and the total MOAS scores. Our results highlight the role of GM volume in left inferior frontal gyri in patients with history of aggression. This evidence ties in well with previous data reporting involvement of these regions in response control and semantic networks.

Cortical structure abnormalities in females with conduct disorder prior to age 15

Among females, conduct disorder (CD) before age 15 is associated with multiple adverse outcomes in adulthood. The few existing structural neuroimaging studies of females with CD report abnormalities of gray matter volumes. The present study compared cortical thickness and surface area of young women with childhood/adolescent CD and healthy women to determine whether cortical abnormalities were present in adulthood and whether they were related to prior CD. Structural brain images from 31 women with CD and 25 healthy women were analyzed using FreeSurfer. Group differences between cortical thickness and surface area were assessed using cluster-wise corrections with Monte Carlo simulations. Women with prior CD, relative to healthy women, showed: (1) reduced cortical thickness in left fusiform gyrus extending up to entorhinal cortex and lingual gyrus; (2) reduced surface area in right superior parietal cortex; (3) increased surface area in left superior temporal gyrus, and right precentral gyrus. These differences remained significant after adjusting for past comorbid disorders, current symptoms of anxiety and depression, current substance use as well as maltreatment. The study suggests that among females, CD prior to age 15 is associated with cortical structure abnormalities in brain regions involved in emotion processing and social interaction.

A preliminary study of cortical morphology in schizophrenia patients with a history of violence

Clinical studies of patients with schizophrenia and a history of violence are challenging both from an ethical and practical perspective, and the neurobiological underpinnings remain largely unknown. We here present a comprehensive account of the brain cortical characteristics associated with violence in schizophrenia. We obtained 3T MRI scans and thorough clinical characterization of schizophrenia patients with a history of violence (murder, attempted murder, criminal assault, SCZ-V, n = 11), schizophrenia patients with no history of violence (SCZ-NV, n = 17), and healthy controls (HC, n = 19). Cortical thickness, area, and folding were analyzed vertex-wise across the cortical mantle (FreeSurfer). SCZ-V had significantly increased cortical folding in the visual and orbitofrontal cortex, and reduced cortical thickness within the precentral-, parietal-, temporal-, and fusiform cortex compared to SCZ-NV, as well as widespread regional thinning and increased folding compared to HC. There were no group differences in cortical area. A major limitation is the small subject sample. If replicated, the results from this pilot study suggest cortical abnormalities in areas involved in sensory processing, emotion recognition, and reward to be of importance to the neurobiology of violence in schizophrenia.

Variation in fourteen brain structure volumes in schizophrenia: A comprehensive meta-analysis of 246 studies

Despite hundreds of structural MRI studies documenting smaller brain volumes on average in schizophrenia compared to controls, little attention has been paid to group differences in the variability of brain volumes. Examination of variability may help interpret mean group differences in brain volumes and aid in better understanding the heterogeneity of schizophrenia. Variability in 246 MRI studies was meta-analyzed for 13 structures that have shown medium to large mean effect sizes (Cohen's d≥0.4): intracranial volume, total brain volume, lateral ventricles, third ventricle, total gray matter, frontal gray matter, prefrontal gray matter, temporal gray matter, superior temporal gyrus gray matter, planum temporale, hippocampus, fusiform gyrus, insula; and a control structure, caudate nucleus. No significant differences in variability in cortical/subcortical volumes were detected in schizophrenia relative to controls. In contrast, increased variability was found in schizophrenia compared to controls for intracranial and especially lateral and third ventricle volumes. These findings highlight the need for more attention to ventricles and detailed analyses of brain volume distributions to better elucidate the pathophysiology of schizophrenia.

The neural basis of hostility-related dimensions in schizophrenia

Hostility and related dimensions like anger, urgency, impulsivity and aggressiveness have been described in non-clinical populations and various serious mental illnesses including schizophrenia. Although representing a mental healthcare challenge, the investigation of such constructs is often limited by the presence of complex and multi-factorial causes and lack of agreement in their conceptualisation and measurement. In this review, we aim to clarify the anatomical basis of hostility-related dimensions in schizophrenia. Imaging studies suggest malfunctioning of a neural circuitry including amygdala, striatum, prefrontal cortex, anterior cingulate cortex, insula and hippocampus to modulate hostile thoughts and behaviours, at least in the subgroup of patients with schizophrenia who exhibit high levels of urgency, impulsivity and aggressiveness.

Some neuroanatomical insights to impulsive aggression in schizophrenia

Patients with schizophrenia are at increased risk of engaging in violence towards others, compared to both the general population and most other patient groups. We have here explored the role of cortico-limbic impairments in schizophrenia, and have considered these brain regions specifically within the framework of a popular neuroanatomical model of impulsive aggression. In line with this model, evidence in patients with aggressive schizophrenia implicated structural deficits associated with impaired decision-making, emotional control and evaluation, and social information processing, especially in the orbitofrontal and ventrolateral prefrontal cortex. Given the pivotal role of the orbitofrontal and ventrolateral cortex in emotion control and evaluation, structural deficits may result in inappropriate use of socially relevant information and improper recognition of impulses that are in need for regulation. Furthermore, we have extended the original model and incorporated the striatum, important for the generation of aggressive impulses, as well as the hippocampus, a region critical for decision-making, into the model. Lastly, we discuss the question whether structural impairments are specific to aggressive schizophrenia. Our results suggest, that similar findings can be observed in other aggressive patient populations, making the observed impairments non-specific to aggressive schizophrenia. This points towards a shared condition, across pathologies, a potential common denominator being impulsive aggression.

Understanding the Demographic Predictors and Associated Comorbidities in Children Hospitalized with Conduct Disorder

Objective: To determine the demographic predictors and comorbidities in hospitalized children with conduct disorder. Methods: A retrospective analysis was performed using the Nationwide Inpatient Sample (2012–2014). All patients were ≤18 years old and cases with a primary diagnosis of conduct disorder (n = 32,345), and a comparison group with another psychiatric diagnosis (n = 410,479) were identified using the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM)diagnosis codes. A logistic regression model was used to generate the odds ratio (OR) between both groups. Results: Children < 11 years old have a five times greater chance of admission for conduct disorder than adolescents (OR = 5.339). African American males are more likely to be admitted for conduct disorder. Children with conduct disorder from low-income families have a 1.5 times higher likelihood of inpatient admission compared to high-income families. These children have an about eleven times higher odds of comorbid psychosis (OR = 11.810) and seven times higher odds of depression (OR = 7.093) compared to the comparison group. Conclusion: Conduct disorders are more debilitating for children and families than many providers realize. African American males under 11 years are at the highest risk of inpatient management for conduct disorder. These patients have a higher risk of comorbid psychosis and depression, which may further deteriorate the severity of illness and require acute inpatient care.

Brain structure abnormalities in young women who presented conduct disorder in childhood/adolescence

The phenotype and genotype of antisocial behavior among females are different from those among males. Previous studies have documented structural brain alterations in males with antisocial behavior, yet little is known about the neural correlates of female antisocial behavior. The present study examined young women who had presented conduct disorder (CDW) prior to age 15 to determine whether brain abnormalities are present in adulthood and whether the observed abnormalities are associated with comorbid disorders or maltreatment that typically characterize this population. Using magnetic resonance imaging and voxel-based morphometry, we compared gray matter volumes (GMV) of 31 women who presented CD by midadolescence and 25 healthy women (HW), age, on average, 23 years. Participants completed structured, validated interviews to diagnose mental disorders, and validated questionnaires to document physical and sexual abuse. Relative to HW, CDW presented increased GMV in the left superior temporal gyrus that was associated with past alcohol and drug dependence, current use of alcohol and drugs, and current anxiety and depression symptoms and maltreatment. Additionally, CDW displayed reduced GMV in lingual gyrus, hippocampus, and anterior cingulate cortex that was associated with past comorbid disorders, current alcohol and drugs use, current anxiety and depression symptoms, and maltreatment. The CDW also presented reduced total GMV that was associated with past comorbid disorders and current anxiety/depression symptoms. Alterations of brain structure were observed among young adult females with prior CD, relative to HW, all of which were associated with internalizing and externalizing disorders and maltreatment that typically accompany CD.

Imaging Violence in Schizophrenia: A Systematic Review and Critical Discussion of the MRI Literature

Background: Persons with schizophrenia have a small but significant increase in risk of violence, which remains after controlling for known environmental risk factors. In vivo MRI-studies may point toward the biological underpinnings of psychotic violence, and neuroimaging has increasingly been used in forensic and legal settings despite unclear relevance. Objectives: (1) To present the first systematic review, following standardized guidelines, of MRI studies of violence with schizophrenia. (2) To critically discuss the promises and pitfalls of using this literature to understand violence in schizophrenia in clinical, forensic, and legal settings. Methods: Following the PRISMA guidelines and literature searches until January 2018, we found 21 original studies that fulfilled the inclusion criteria: (1) Studies of persons with schizophrenia, (2) a history of violence or aggressive behavior, (3) the use of one or more MRI-modalities (sMRI, DTI, fMRI). Results: The most consistent findings from the structural studies were reduced volumes of the hippocampus and the frontal lobe (in particular the orbitofrontal and anterior cingulate cortex) in schizophrenia patients with a history of violence or higher aggression scores. The functional studies mainly showed differences and aggression correlates in the frontal lobe and amygdala. However, the studies were methodologically heterogeneous, with four particular areas of concern: different definitions of violence, region of interest vs. whole-brain studies, small subject samples, and group comparisons in a heterogeneous diagnostic category (schizophrenia). Conclusion: The literature reports subtle, but inconsistent group level differences in brain structure and function associated with violence and aggression with schizophrenia, in particular in areas involved in the formation of psychosis symptoms and affective regulation. Due to methodological challenges the results should be interpreted with caution. In order to come closer to the neurobiological underpinnings of violence in schizophrenia future studies could: (1) address the neurobiological differences of premeditated and reactive violence, (2) use RDoC criteria, for example, or other symptom-based systems to categorize psychosis patients, (3) increase subject cohorts and apply new data driven methods. In this perspective, MRI-studies of violence in schizophrenia have the potential to inform clinical violence prediction and legal evaluations in the future.

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.

Neural Mechanisms Underlying Affective Theory of Mind in Violent Antisocial Personality Disorder and/or Schizophrenia

Among violent offenders with schizophrenia, there are 2 sub-groups, one with and one without, conduct disorder (CD) and antisocial personality disorder (ASPD), who differ as to treatment response and alterations of brain structure. The present study aimed to determine whether the 2 groups also differ in Theory of Mind and neural activations subsuming this task. Five groups of men were compared: 3 groups of violent offenders-schizophrenia plus CD/ASPD, schizophrenia with no history of antisocial behavior prior to illness onset, and CD/ASPD with no severe mental illness-and 2 groups of non-offenders, one with schizophrenia and one without (H). Participants completed diagnostic interviews, the Psychopathy Checklist Screening Version Interview, the Interpersonal Reactivity Index, authorized access to clinical and criminal files, and underwent functional magnetic resonance imaging while completing an adapted version of the Reading-the-Mind-in-the-Eyes Task (RMET). Relative to H, nonviolent and violent men with schizophrenia and not CD/ASPD performed more poorly on the RMET, while violent offenders with CD/ASPD, both those with and without schizophrenia, performed similarly. The 2 groups of violent offenders with CD/ASPD, both those with and without schizophrenia, relative to the other groups, displayed higher levels of activation in a network of prefrontal and temporal-parietal regions and reduced activation in the amygdala. Relative to men without CD/ASPD, both groups of violent offenders with CD/ASPD displayed a distinct pattern of neural responses during emotional/mental state attribution pointing to distinct and comparatively successful processing of social information.

Aggressive Behavior Among Persons With Schizophrenia and Those Who Are Developing Schizophrenia: Attempting to Understand the Limited Evidence on Causality

People with, and those who are developing, schizophrenia are at increased risk to engage in aggressive behavior (AGB). Some incidents lead to criminal prosecution. Most people with schizophrenia who commit crimes engage in delinquency and/or AGB prior to first episode. A large proportion of these individuals have a history of childhood conduct disorder (CD) and brain abnormalities suggestive of abnormal neural development distinctive from that of others with schizophrenia. Factors contributing to schizophrenia that is preceded by CD include failing to learn not-to-behave aggressively in early childhood, impairments in understanding emotions in the faces of others, maltreatment, and subsequent re-victimization. Others with no history of antisocial behavior begin engaging in AGB as positive symptoms increase and illness onsets. They too are at elevated risk to be victimized. Specific genetic variants linked to stress regulation in combination with adversity have been associated both with AGB and psychotic symptoms. Effectively treating conduct problems and preventing victimization would reduce AGB by persons with schizophrenia.

New Clinically Relevant Findings about Violence by People with Schizophrenia

OBJECTIVE

To review findings with clinical relevance that add to knowledge about antisocial and aggressive behaviour among persons with schizophrenia.

METHOD

Nonsystematic literature review.

RESULTS

Recent evidence shows that individuals who develop schizophrenia present cognitive deficits, psychotic-like experiences, and internalizing and externalizing problems from childhood onwards. Many of their relatives present not only schizophrenia-related disorders but also antisocial behaviour. While the increased risk of aggressive behaviour among persons with schizophrenia has been robustly established, recent findings show that by first contact with clinical services for psychosis, most people with schizophrenia who will engage in aggressive behaviour may be identified. At first episode, 2 distinct types are distinguishable: those who present a history of antisocial and aggressive behaviour since childhood and those who began engaging in aggressive behaviour as illness onsets. Antipsychotic medications and other treatments shown to be effective for schizophrenia are needed by both types of patients. Additionally, those with a history of antisocial and aggressive behaviour since childhood require cognitive-behavioural programs aimed at reducing these behaviours and promoting prosocial behaviour. Reducing physical victimisation and cannabis use will likely reduce aggressive behaviour. Evidence suggests that threats to hurt others often precede assaults.

CONCLUSIONS

At first contact with services, patients with schizophrenia who have engaged in aggressive behaviour should be identified and treated for schizophrenia and for aggression. Research is needed to identify interactions between genotypes and environmental factors, from conception onwards, that promote and that protect against the development of aggressive behaviour among persons with schizophrenia.

Monoamine oxidase and agitation in psychiatric patients

Subjects with schizophrenia or conduct disorder display a lifelong pattern of antisocial, aggressive and violent behavior and agitation. Monoamine oxidase (MAO) is an enzyme involved in the degradation of various monoamine neurotransmitters and neuromodulators and therefore has a role in various psychiatric and neurodegenerative disorders and pathological behaviors. Platelet MAO-B activity has been associated with psychopathy- and aggression-related personality traits, while variants of the MAOA and MAOB genes have been associated with diverse clinical phenotypes, including aggressiveness, antisocial problems and violent delinquency. The aim of the study was to evaluate the association of platelet MAO-B activity, MAOB rs1799836 polymorphism and MAOA uVNTR polymorphism with severe agitation in 363 subjects with schizophrenia and conduct disorder. The results demonstrated significant association of severe agitation and smoking, but not diagnosis or age, with platelet MAO-B activity. Higher platelet MAO-B activity was found in subjects with severe agitation compared to non-agitated subjects. Platelet MAO-B activity was not associated with MAOB rs1799836 polymorphism. These results suggested the association between increased platelet MAO-B activity and severe agitation. No significant association was found between severe agitation and MAOA uVNTR or MAOB rs1799836 polymorphism, revealing that these individual polymorphisms in MAO genes are not related to severe agitation in subjects with schizophrenia and conduct disorder. As our study included 363 homogenous Caucasian male subjects, our data showing this negative genetic association will be a useful addition to future meta-analyses.

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.

ZNF804A rs1344706 is associated with cortical thickness, surface area, and cortical volume of the unmedicated first episode schizophrenia and healthy controls

The effects of ZNF804A rs1344706, a prominent susceptibility gene for schizophrenia, on gray matter (GM) structure in unmedicated schizophrenia (SZ) patients are still unknown, although several previous studies investigated the effects in medicated SZ patients and healthy controls (HC). Analyzing cortical thickness, surface area, and GM volume simultaneously may provide a more precise and complete picture of the effects. We genotyped 59 unmedicated first episode SZ patients and 60 healthy controls for the ZNF804A single nucleotide polymorphism (SNP) rs1344706, and examined between-group differences in cortical thickness, surface area, and cortical volume using a full-factorial 2 × 2 analysis of variance (ANOVA). We found the risk allele (T) in ZNF804A rs1344706, compared to the non-risk allele (G), was associated with thinner cortex in the bilateral precuneus, left precentral gyrus, and several other regions, associated with a smaller cortical surface area in the left superior parietal, precuneus cortex and left superior frontal, and associated with a lower cortical volume in the left superior frontal, left precentral, and right precuneus in SZ patients. In contrast, in the controls, the T allele was associated with the increased cortical measurements compared to the G allele in the same regions as those mentioned above. ZNF804A rs1344706 has significant, but different, effects on cortical thickness, surface area, and cortical volume in multiple regions of the brain cortex. Our findings suggest that ZNF804A rs1344706 may aggravate the risk for schizophrenia by exerting its effects on cortical thickness, surface area, and cortical volume in these brain regions.

Aggression in Psychoses

Most individuals diagnosed with a mental illness are not violent, but some mentally ill patients commit violent acts. PubMed database was searched for articles published between 1980 and November 2013 using the combination of key words “schizophrenia” or “bipolar disorder” with “aggression” or “violence.” In comparison with the general population, there is approximately a twofold increase of risk of violence in schizophrenia without substance abuse comorbidity and ninefold with such comorbidity. The risk in bipolar disorder is at least as high as in schizophrenia. Most of the violence in bipolar disorder occurs during the manic phase. Violence among adults with schizophrenia may follow two distinct pathways: one associated with antisocial conduct and another associated with the acute psychopathology, particularly anger and delusions. Clozapine is the most effective treatment of aggressive behavior in schizophrenia. Emerging evidence suggests that olanzapine may be the second most effective treatment. Treatment nonadherence greatly increases the risk of violent behavior, and poor insight as well as hostility is associated with nonadherence. Nonpharmacological methods of treatment of aggression in schizophrenia and bipolar disorder are increasingly important. Cognitive behavioral approaches appear to be effective in cases where pharmacotherapy alone is not sufficient.

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.