The comparative study of the early stages of sensory and sensory-motor information processing in aggressive and non-aggressive schizophrenic patients

Abstract

To study the early stages of sensory (P50 suppression) and sensorimotor (prepulse modification of acoustic startle reaction - ASR) information processing in aggressive and non-aggressive patients with schizophrenia. Two groups (aggressive group A, 44 s. and non-aggressive group NA, 27 s.) and 48 healthy people were studied using oculography and encephalography. Symptoms of schizophrenia were assessed by PANSS. The analysis of ASR and P50 revealed the increased ASR latency, deficit of prepulse inhibition (PPI) with 60 ms leading interval, and P50 suppression in patients compared to controls. Aggressive behavior impacted on lateral features of ASR changes in the group A. The increase of ASR amplitude and the decline of prepulse facilitation were found in the group NA. The P50 analysis revealed the increased P50 amplitude and the shortened latency in response to 2nd stimulus in the pair. The increase in scores on item G14 of the PANSS (Poor impulse control) in the group A and its correlations with ASR and P50 parameters in this group suggested the important role of impulsivity in aggressive behavior in the studied sample of aggressive patients. ASR and P50 characteristics in the group NA are associated with increased sensitivity to incoming stimuli and such personality traits as increased alertness and fear, which might inhibit aggression. Thus, indicators of the early stages of information processing can be considered as potential predictors of aggressive behavior.