Visual P3 abnormalities in patients with first-episode schizophrenia, unaffected siblings of schizophrenia patients and individuals at ultra-high risk for psychosis.

Cued version of the continuous performance test (AX-CPT) assesses sustained attention, working memory and cognitive control processes, which have been reported as impaired in schizophrenia. This study investigated visual P3 event-related potential elicited during cued CPT in patients with schizophrenia and in individuals who were at clinical or genetic high risk for psychosis to determine whether any abnormality may provide a marker of vulnerability for psychosis. Visual P3 elicited during cued CPT have not been reported in individuals at high risk for psychosis.

Lack of progressive reduction in P3 amplitude after the first-episode of schizophrenia: A 6-year follow-up study.

P3 event-related potential may track the course of neurophysiological pathology in schizophrenia. Reduction in the amplitude of the auditory P3 is a widely replicated finding, already present at the first psychotic episode, in schizophrenia. Whether a progressive deficit is present in auditory P3 in schizophrenia over the course of illness is yet to be clarified.

Time-frequency analysis of the event-related potentials associated with the Stroop test.

Multiple executive processes are suggested to be engaged at Stroop test, and time-frequency analysis is acknowledged to improve the informative utility of EEG in cognitive brain research. We aimed to investigate event-related oscillations associated with the Stroop test. EEG data was collected from 23 healthy volunteers while they performed a computer version of Stroop test.

Cognitive deficits in clinical and familial high risk groups for psychosis are common as in first episode schizophrenia.

The aim of this study is to compare the neurocognitive functions in individuals with clinical or genetic risk for psychosis, in patients with first-episode schizophrenia (FES) and in healthy controls. We compared cognitive functions of 52 individuals at ultra high risk (UHR) for psychosis, 53 patients with FES, their 30 healthy siblings (familial high risk group, FHR) and controls. FES group had worse neuropsychological performance than controls in all of the domains.

N2 and P3 potentials in early-onset and late-onset patients with obsessive-compulsive disorder.

Background: Impaired cognitive control processes may be central in the pathogenesis of obsessive-compulsive disorder (OCD). Our objective was to evaluate cognitive control processes with event-related potentials in early-onset OCD (EO) and late-onset OCD (LO), which are suggested to have distinct characteristics.

Methods: Participants were unmedicated EO (n = 26) and LO patients (n = 33) without comorbid psychopathology and healthy controls (n = 54).

P50 gating at acute and post-acute phases of first-episode schizophrenia.

Deficit in P50 sensory gating has repeatedly been shown in schizophrenia. In order to determine the contribution of trait and/or state features to P50 gating deficit in schizophrenia we evaluated the P50 gating in patients with first-episode schizophrenia (FES) at acute and post-acute phases. Subject groups comprised 16 patients with FES and 24 healthy controls.

Mismatch negativity at acute and post-acute phases of first-episode schizophrenia.

The objective of this study was to evaluate the mismatch negativity (MMN) in patients with first-episode schizophrenia at acute and post-acute phases in order to determine the contribution of trait and/or state features to MMN disturbances in schizophrenia. Subject groups comprised 30 patients with first-episode schizophrenia at the acute phase and 34 healthy controls. Ten patients were neuroleptic-naive during testing at the acute phase.

Novelty P3 and P3b in first-episode schizophrenia and chronic schizophrenia.

The objective of this study was to evaluate P3b and novelty P3 responses in patients with first-episode schizophrenia (FES) and chronic schizophrenia (CS). P3b is consistently reported to be reduced in CS. However, novelty P3 results in CS are controversial.