Differences in Neuropsychological Functioning Between Homicidal and Nonviolent Schizophrenia Samples

Executive functioning in antisocial behavior: A multi-level systematic meta-analysis

Neurobiological information - including executive functioning - is increasingly relevant for forensic clinical practice, as well as for the criminal justice system. Previous meta-analyses report that antisocial populations show impaired performance on executive functioning tasks, but these meta-analyses are outdated, have limitations in their methodological approach, and are therefore in need of an update. The current multi-level meta-analysis including 133 studies (2008-2023) confirms impaired performance in executive functioning (d=.42), but studies are heterogeneous. Several moderator analyses showed that neuropsychological test used, type of executive function component, and control group characteristics moderated the overall effect. Specifically, matching psychiatric problems in the non-antisocial control group eliminated any differences in executive functioning between groups. No moderation effects were found for assessment quality, hot or cold executive functions, and various population characteristics. These results could indicate that the assessment of executive functioning in antisocial populations may be less relevant for recidivism risk assessment than thought, although this should first be assessed in prospective longitudinal studies. Executive functioning could potentially be used to identify or screen for individuals with certain treatment needs or be used as a responsivity factor, especially in disorders which are often underdiagnosed in criminal justice settings.

The "zipper model of empathy" applied to violence in schizophrenia: A search for social cognitive underpinnings of lack of empathic behavior

BACKGROUND

The "zipper model of empathy" has been proposed for psychopathy. It postulates that empathic behavior may fail to arise due to impaired facial emotion recognition. In this study, we examined if the model may be of relevance for schizophrenia.

METHODS

In a sample of participants with schizophrenia and a history of severe interpersonal violence, associations between measures of social cognition (emotion recognition, theory of mind) and aspects of psychopathy (lack of empathy, lack of remorse) were investigated. A non-violent sample experiencing schizophrenia served as a control group.

RESULTS

Correlation analyses revealed a specific and statistically significant association between facial emotion recognition and lack of empathy in the violent sample. Follow-up analyses identified that neutral emotions were of particular importance. Logistic regression analyses confirmed that impairments in facial emotion recognition predicted levels of empathy in the violent sample experiencing schizophrenia.

CONCLUSIONS

Our results suggest that the "zipper model of empathy" may be relevant for schizophrenia. The findings further point to the potential benefit of including social cognitive training in the treatment of persons with schizophrenia and a history of interpersonal aggression.

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.

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.

Suicidal Offenders and Non-Offenders with Schizophrenia Spectrum Disorders: A Retrospective Evaluation of Distinguishing Factors Using Machine Learning

Patients with schizophrenia spectrum disorders (SSD) have an elevated risk of suicidality. The same has been found for people within the penitentiary system, suggesting a cumulative effect for offender patients suffering from SSD. While there appear to be overlapping characteristics, there is little research on factors distinguishing between offenders and non-offenders with SSD regarding suicidality. Our study therefore aimed at evaluating distinguishing such factors through the application of supervised machine learning (ML) algorithms on a dataset of 232 offenders and 167 non-offender patients with SSD and history of suicidality. With an AUC of 0.81, Naïve Bayes outperformed all other ML algorithms. The following factors emerged as most powerful in their interplay in distinguishing between offender and non-offender patients with a history of suicidality: Prior outpatient psychiatric treatment, regular intake of antipsychotic medication, global cognitive deficit, a prescription of antidepressants during the referenced hospitalisation and higher levels of anxiety and a lack of spontaneity and flow of conversation measured by an adapted positive and negative syndrome scale (PANSS). Interestingly, neither aggression nor overall psychopathology emerged as distinguishers between the two groups. The present findings contribute to a better understanding of suicidality in offender and non-offender patients with SSD and their differing characteristics.

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.

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).

Childhood trauma, social cognition and schizophrenia: Specific association between physical neglect and cognitive theory of mind in homicide offenders

Schizophrenia is associated with a small, but increased risk of violent behavior, including homicide. Violent individuals with schizophrenia have elevated rates of childhood trauma and substantial social cognitive impairments. The aim of this study was to examine if childhood trauma is related to social cognition in homicide offenders with schizophrenia. We recruited 26 individuals with schizophrenia sentenced to compulsory mental care for homicide/attempted homicide and 28 non-violent schizophrenia controls. They filled out the Childhood Trauma Questionnaire (CTQ), providing scores for physical abuse, sexual abuse, emotional abuse, physical neglect and emotional neglect. Social cognition was assessed with two measures of emotion processing (Emotion in Biological Motion, Pictures of Facial Affect) and two theory of mind (ToM) tests (Hinting Task, Movie for the Assessment of Social Cognition: MASC). Spearman's rho correlation coefficients were computed, and significant results followed up with partial correlation analyses controlling for IQ. Three associations were statistically significant, all in the homicide group; between CTQ physical neglect and cognitive ToM assessed with Hinting Task and with MASC, and between CTQ emotional neglect and Hinting Task. Only the first remained significant after controlling for IQ, indicating a specific association between physical neglect and cognitive ToM in homicide offenders with schizophrenia.

Forensic psychiatric evaluation of 187 homicidal assailants with and without a schizophrenia spectrum disorder: Clinical, criminological and behavioral characteristics

Intentional homicide, a declining phenomenon in Italy, represents one of the most extreme forms of violence. A specific subgroup of homicidal assailants is represented by those affected by mental disorders, where the relationship between psychopathology and characteristics of the homicidal attack is not yet fully understood. We analyzed the case files of 187 homicides or attempted homicides, in which the defendant had undergone a forensic psychiatric evaluation within the previous 10 years from a single forensic psychiatric center. We described and analyzed the perpetrator, victim and criminological characteristics of the study cases. A diagnosis of a schizophrenia spectrum disorder, a victim who was the perpetrator's biological child and absence of a personality disorder diagnosis were associated with an increased probability of having been adjudicated as lacking or having substantially diminished criminal responsibility due to a mental disorder. Homicidal assailants with a schizophrenia spectrum disorder showed some differences in criminological characteristics compared with murderers without a schizophrenic spectrum disorder, including a higher incidence of parricide, interruption of pharmacotherapy before the crime and disorganized post-crime behavior.

Dissociative Aggression Triggered by Headache

Headache is generally perceived as a negative symptom focused on oneself. However, there are reports suggesting that patients suffering from pain, especially headache, can be aggressive. The precise nature of the link between headache and aggression is not known. Here, we describe a homicidal attack, triggered by headache, in a middle-aged man. The patient's background and the characteristics of the attack suggested a dissociative behavior. The case shows that headache may be a trigger for homicidal behavior. Case-control studies are needed to determine the prevalence of aggressive tendencies in patients with headache.

Women and Men who Committed Murder: Male/Female Psychopathic Homicides

The present study was designed to compare gender differences in psychiatric diagnosis with the dimension of psychopathy in women and men who had attempted or committed homicide. The study samples consisted of 39 homicidal females and 48 homicidal males who were confined in one of Italy's REMS or prison facilities in two southern provinces of Italy (Puglia and Basilicata). Assessment instruments included the SCID-5, the PID-5 IRF, and the PCL-R. Each gender group was stratified according to the level of criminal responsibility for the homicidal offense (full, partial, absent), and after assessments, according to the degree of the psychopathic dimension. There were clear gender differences in homicidal individuals. Female offenders were less likely to have had a record of criminal charges/convictions or imprisonment, and their homicides were more often intrafamilial, victimizing especially of their children, whereas males targeted intimate partners and extrafamilial victims. In the entire group, there was an inverse relationship between the level of psychopathy and the personality disorder on one side, and the psychotic disturbance on the other. Factor 2 (lifestyle/antisocial dimension) of the PCL-R was higher among the homicidal males, whereas females tended to score higher on Factor 1 (the interpersonal/affective dimension). Finally, if the psychopathic dimension is a qualifier for antisocial personality disorder, as indicated in DSM-5, this appears to be less true for females who tend to have other personality disorders.

Attention Problems Predict Risk of Violence and Rehabilitative Engagement in Mentally Disordered Offenders

Mentally disordered offenders (MDOs) endorse difficulties with attention, impulsivity, and hyperactivity. Assessing these difficulties among MDOs may confer practical benefits for the management and provision of care for this population, by informing strategies to improve rehabilitative engagement and risk assessments for violence. However, there is a dearth of literature exploring these cognitive problems in MDOs in relation to outcome factors. Forty-eight MDOs from a high-security hospital completed the QbTest, which measures the domains of inattention, impulsivity, and hyperactivity. Comprehensive file review of clinical and occupational/vocational rehabilitative engagement and Historical Clinical Risk Management-20 (HCR-20) were used as outcome measures of interest. Participants displayed greater cognitive deficits in attention, impulsivity, and hyperactivity compared to the general population. The domain of inattention and omission errors was related to occupational/vocational therapy engagement as well as a higher risk of present and future violence as measured by the HCR-20. The findings suggest that QbTest is a helpful objective tool that could be incorporated into the assessment of MDOs. Specifically, inattention emerged as a strong predictor of patients' risk of violence as well as patient's vocational therapy engagement. Therefore, cognitive skills programs targeting attention problems should be introduced to improve outcomes for this population.

Large social cognitive impairments characterize homicide offenders with schizophrenia

Schizophrenia is associated with an increased violence risk, particularly homicide. One possible, but scarcely explored, contributor to the increased violence risk is social cognitive impairment. Individuals with schizophrenia show impairments in social cognition that are associated with poor functional outcome. This study examined social cognition among homicide offenders with schizophrenia (HOS), applying validated measures of emotion perception and theory of mind (ToM). Two groups of individuals with schizophrenia were compared, one had committed homicide (HOS, n = 26), and the other had no violence history (non-HOS, n = 28). Healthy controls (HC, n = 71) were included as reference group for one measure. Emotion perception was indexed by the Emotion in Biological Motion (Emotion) and Pictures of Facial Affect (PFA) tests. ToM was assessed with the Hinting Task and Movie for the Assessment of Social Cognition (MASC). The results showed that HOS participants had significantly poorer performance than non-HOS in both emotion perception and ToM. For the MASC test, HOS participants showed large deficits compared to HC (-4 standard deviations). Particularly, HOS participants made a substantial number of undermentalizing errors. The results suggest that emotion perception deficits and a tendency to undermentalize may be important for understanding homicide in schizophrenia.

Impaired neuropsychological profile in homicide offenders with schizophrenia

BACKGROUND

Our ability to predict and prevent homicides committed by individuals with schizophrenia is limited. Cognitive impairments are associated with poorer functional outcome in schizophrenia, possibly also homicide. The aim of the current study was to investigate global and specific cognition among homicide offenders with schizophrenia (HOS).

METHODS

Twenty-six HOS were compared to 28 individuals with schizophrenia and no history of violence (non-HOS), and a group of healthy controls (HC, n = 151). HOS and non-HOS participants were recruited from in- and outpatient units across Norway. An extensive neuropsychological test battery was administered.

RESULTS

HOS participants performed significantly weaker than HC in all cognitive domains. Further, statistically significant differences between HOS and non-HOS participants were found for IQ (d = 0.52) and verbal learning (d = 0.82), with larger impairments in the HOS compared to the non-HOS group.

CONCLUSIONS

Our results indicate that HOS participants show clinically significant impairments in global and specific cognition.