Prolonged P300 Latency in Antipsychotic-Free Subjects with At-Risk Mental States Who Later Developed Schizophrenia

Abstract

We measured P300, an event-related potential, in subjects with at-risk mental states (ARMS) and aimed to determine whether P300 parameter can predict progression to overt schizophrenia. Thirty-three subjects with ARMS, 39 with schizophrenia, and 28 healthy controls participated in the study. All subjects were antipsychotic-free. Subjects with ARMS were followed-up for more than two years. Cognitive function was measured by the Brief assessment of Cognition in Schizophrenia (BACS) and Schizophrenia Cognition Rating Scale (SCoRS), while the modified Global Assessment of Functioning (mGAF) was used to assess global function. Patients with schizophrenia showed smaller P300 amplitudes and prolonged latency at Pz compared to those of healthy controls and subjects with ARMS. During the follow-up period, eight out of 33 subjects with ARMS developed overt psychosis (ARMS-P) while 25 did not (ARMS-NP). P300 latency of ARMS-P was significantly longer than that of ARMS-NP. At baseline, ARMS-P elicited worse cognitive functions, as measured by the BACS and SCoRS compared to ARMS-NP. We also detected a significant relationship between P300 amplitudes and mGAF scores in ARMS subjects. Our results suggest the usefulness of prolonged P300 latency and cognitive impairment as a predictive marker of later development of schizophrenia in vulnerable individuals.

Unveiling the Associations between EEG Indices and Cognitive Deficits in Schizophrenia-Spectrum Disorders: A Systematic Review

“…Discrepancies are also found in the literature relevant to correlation between P3b and cognitive functions in SCZ, FES and high-risk subjects. Indeed, most studies found a positive correlation between P3b amplitude and several cognitive domains [ 91 , 157 , 162 , 163 , 197 , 200 , 201 , 204 , 208 , 211 , 212 , 214 , 215 , 216 , 217 , 218 , 219 , 220 , 221 ], while some studies found no significant correlation [ 161 , 210 , 213 , 220 ].…”

“…As such, P300 has been one of the most studied ERP components in this context [ 278 ]. Associations between amplitude reductions in P300 [ 156 , 203 ] or its two subtypes, P3a [ 180 , 192 , 208 ] and P3b [ 201 , 208 , 211 , 215 , 216 , 218 , 219 , 220 ], with deficits in attention is one of the most consistent EEG finding in schizophrenia [ 156 , 163 , 192 , 201 , 203 , 208 , 215 , 218 ], first-episode psychosis [ 180 , 197 , 211 ] and clinical high-risk [ 216 , 219 ] subjects. Associations of P300 amplitude reduction with verbal learning and memory deficits have also been reported [ 96 , 115 , 157 , 162 , 180 , 200 , 206 , 217 , 218 , 220 ] and suggest that impairments in identifying and responding to stimuli that are either salient or novel might also influence higher-order steps of cognitive processing relevant to goal directed behaviour.…”

Study on clinical characteristics of event‐related potential P300 in elderly schizophrenics and associated risk factors

“…Dominated by symptoms of psychotic diseases, the two can influence each other in a certain stressful situation, which may increase impulsivity and anger, and induce violent events. Event‐related potential (ERP) P300 component is a relatively objective electroencephalogram biological indicator reflecting cognitive psychological activity, which can be used to predict the development of schizophrenia in a susceptible population (Higuchi et al., 2021).…”

Auditory P300 in individuals with high schizotypy: associations of schizotypal traits with amplitude and latency under different oddball conditions

“…P300 is a late cognitive component of event-related potentials (ERPs), which is thought to reflect a working memory update of change and attention ( Nieman et al, 2002 ). Deficits in auditory P300 measures are potential neurophysiological markers of schizophrenia ( Wang et al, 2003 ; Higuchi et al, 2013 , 2021 ; Kim et al, 2015 ). Previous studies reported that lower amplitude and longer latency of P300 in patients with schizophrenia ( Bramon et al, 2004 ; De Wilde et al, 2008 ; Kim et al, 2015 ), in their first-degree biological relatives, and in the individuals with clinical high risk for psychosis ( Ozgürdal et al, 2008 ; Hamilton et al, 2019 ).…”