Neural Correlates of Psychopathic Traits in Schizophrenia: fMRI Study of Response Inhibition in Persistently Violent Patients.

Background And Hypothesis: Psychopathic traits play an important role in schizophrenia, particularly for violent behavior. There have been very few functional imaging studies (fMRI) examining the impact of brain dysfunction on psychopathic traits in schizophrenia. Our goal was to evaluate neural abnormalities underlying these traits through fMRI in violent subjects with schizophrenia (VS) and in 3 comparison groups: healthy controls (HC), nonviolent patients (NV), and nonpsychotic violent subjects (NPV).

Separate pathways to violent behavior in schizophrenia and in the general population.

Violence in schizophrenia is best investigated within the broader context of violent behavior in the general population. Two important domains of general pathology which allow us to take such an approach include impairment in emotion processing, as manifested by faulty facial emotion recognition, and aggressive reactivity which consists of heightened sensitivity to provocation. To test this approach, we included 135 subjects: 38 violent (VS's) and 33 nonviolent patients with schizophrenia, 32 healthy controls and 32 non-psychotic violent subjects (NPV's).

Distinctive profiles of traits predisposing to violence in schizophrenia and in the general population.

Objective: We delineated important trait predispositions to violence, including psychopathic and impulsive traits and trait aggression, in patients with schizophrenia and in the general population.

Method: The study included 144 subjects: 40 violent (VS's) and 34 nonviolent (NV's) patients with schizophrenia, 35 healthy controls (HC's) and 35 non-psychotic violent subjects (NPV's). We used the Psychopathy Checklist, Buss-Perry Aggression Questionnaire, and Barratt Impulsiveness Scale (BIS-11).

Neuroanatomical Abnormalities in Violent Individuals with and without a Diagnosis of Schizophrenia.

Several structural brain abnormalities have been associated with aggression in patients with schizophrenia. However, little is known about shared and distinct abnormalities underlying aggression in these subjects and non-psychotic violent individuals. We applied a region-of-interest volumetric analysis of the amygdala, hippocampus, and thalamus bilaterally, as well as whole brain and ventricular volumes to investigate violent (n = 37) and non-violent chronic patients (n = 26) with schizophrenia, non-psychotic violent (n = 24) as well as healthy control subjects (n = 24).

Proneness to aggression and its inhibition in schizophrenia: Interconnections between personality traits, cognitive function and emotional processing.

Objective: Research on aggression in schizophrenia has focused on narrowly defined deficits, while ignoring interconnections among these impairments which provide better explanatory power. Our goal was to investigate interrelations among impairments in important domains related to aggression: personality traits, including psychopathy and impulsivity, cognition and processing of emotions.

Method: 34 healthy controls, 37 high aggression (HAG) and 31 low aggression (LAG) patients with schizophrenia participated.

Disturbances in Response Inhibition and Emotional Processing as Potential Pathways to Violence in Schizophrenia: A High-Density Event-Related Potential Study.

Objective: Increased susceptibility to emotional triggers and poor response inhibition are important in the etiology of violence in schizophrenia. Our goal was to evaluate abnormalities in neurophysiological mechanisms underlying response inhibition and emotional processing in violent patients with schizophrenia (VS) and 3 different comparison groups: nonviolent patients (NV), healthy controls (HC) and nonpsychotic violent subjects (NPV).

Methods: We recorded high-density Event-Related Potentials (ERPs) and behavioral responses during an Emotional Go/NoGo Task in 35 VS, 24 NV, 28 HC and 31 NPV subjects.

Aberrant response inhibition and task switching in psychopathic individuals.

Deficits in cognitive control have been considered a core dysfunction of psychopathy, responsible for disrupted self-control. We investigated cognitive control impairments, including difficulties with task switching, failure of response inhibition, and inability to adjust speed of responding. Participants included 16 subjects with psychopathic traits (Ps), and 22 healthy controls (HCs).

Depression and impulsivity as pathways to violence: implications for antiaggressive treatment.

Background: Difficulties with affect regulation and impulse control have a strong influence on violence. The objective of this study was to determine whether baseline depression and impulsivity predict aggression and whether they predict differential response to antiaggressive treatment. This is important, as we lack knowledge as to the selection of antipsychotics for the treatment of aggression.

The denial of aggression in violent patients with schizophrenia.

Background: There is no literature investigating denial of aggression in schizophrenia. Our goal was to study this phenomenon and to determine what deficits are associated with it.

Methods: 102 inpatients with schizophrenia were divided into three groups: (1) patients with a documented history of violent crime who denied it on extensive interviews ("deniers"); (2) those with such a history who admitted to it; and (3) those without violent crime.

Visual sensory processing deficits in schizophrenia: is there anything to the magnocellular account?

Visual processing studies have repeatedly shown impairment in patients with schizophrenia compared to healthy controls. Electroencephalography (EEG) and, specifically, visual evoked potential (VEP) studies have identified an early marker of this impairment in the form of a decrement in the P1 component of the VEP in patients and their clinically unaffected first-degree relatives. Much behavioral and neuroimaging research has implicated specific dysfunction of either the subcortical magnocellular pathway or the cortical visual dorsal stream in this impairment.

Early sensory-perceptual processing deficits for affectively valenced inputs are more pronounced in schizophrenia patients with a history of violence than in their non-violent peers.

Individuals with schizophrenia are more prone to violent behaviors than the general population. It is increasingly recognized that processing of emotionally valenced stimuli is impaired in schizophrenia, a deficit that may play a role in aggressive behavior. Our goal was to establish whether patients with a history of violence would show more severe deficits in processing emotionally valenced inputs than non-violent patients.

Executive function predicts response to antiaggression treatment in schizophrenia: a randomized controlled trial.

Objective: Despite extensive experience with antipsychotic medications, we have limited capacity to predict which patients will benefit from which medications and for what symptoms. Such prediction is of particular importance for the proper treatment of violence. Our goal was to determine whether executive function predicts outcome of treatment for aggressive behavior and whether such prediction varies across medication groups.

Atypical antipsychotics, neurocognitive deficits, and aggression in schizophrenic patients.

The purpose of this study was to compare the effects of olanzapine, clozapine, and haloperidol on neurocognitive function in schizophrenic patients who present with documented episodes of physical aggression and to determine whether change in cognitive function is related to aggression. One hundred physically aggressive schizophrenic inpatients were assigned to a randomized, double-blind, parallel-group, 12-week treatment, and received cognitive evaluations at baseline. There were 33, 34, and 33 subjects in the clozapine, olanzapine, and haloperidol groups, respectively.

Atypical antipsychotic agents in the treatment of violent patients with schizophrenia and schizoaffective disorder.

Context: Violent behavior of patients with schizophrenia prolongs hospital stay and interferes with their integration into the community. Finding appropriate treatment of violent behaviors is of primary importance.

Objective: To compare the efficacy of 2 atypical antipsychotic agents, clozapine and olanzapine, with one another and with haloperidol in the treatment of physical assaults and other aggressive behaviors in physically assaultive patients with schizophrenia and schizoaffective disorder.