Reduced impulse control and emotion dysregulation are associated with an increased risk of violence in psychosis. We used an emotional stop-signal task (ESST) with angry and neutral facial expressions stimuli to examine the differences in inhibition in neutral and emotional contexts between acutely violent (N = 117) and non-violent (N = 50) patients with schizophrenia spectrum disorders and healthy volunteers (N = 50).
However, 66 violent patients (56.41%) from the final sample with a higher level of self-reported impulsivity did not finish the behavioral task. Inhibition was found to be weaker in emotional than in neutral contexts in both the violent (n = 51) and non-violent patient groups in comparison with healthy controls.
At the same time, violent patients had weaker inhibition in both neutral and emotional contexts than non-violent patients and healthy controls. Violent patients also showed significant associations between response inhibition and positive schizophrenia symptoms.
These results show that emotion regulation impairment is present in schizophrenia patients in general and violent behavior is associated with higher impulsivity regardless of the emotional context. Impaired response inhibition seems to be a stronger indicator for violent patients than the disorder itself, and it may constitute a marker for the risk of violent behavior in psychotic patients.
Positive symptoms might fall into underlying factors of increased impulsivity in acutely violent psychotic patients. However, the emotional stop-signal task seemed to be too strenuous for highly impulsive patients and acutely violent patients with psychosis, and its use was limited to the patients who were able or willing to complete the task.