ABSTRACT
Visual event-related potential (ERP) is an electrophysiological technique that objectively reflects the cognitive processing of stimulus from the perspective of detecting and recording neural electrophysiology responses using different paradigms of visual stimuli. Its endogenous components are closely related to advanced psychological activities. This article introduces the characteristics of main endogenous components including visual mismatch negativity (vMMN), N200 and P300, reviews the research progress of visual ERP in the sequelae of brain injury and objective evaluation of visual function, and prospects the application prospect of visual ERP in the field of forensic medicine.
Subject(s)
Humans , Brain Injuries, Traumatic/complications , Evoked Potentials , Brain Injuries , Forensic MedicineABSTRACT
Event-related potentials (ERP) is some kind of brain potentials that recorded from cranial surface when human cognitive processing an object(pay attention, memorize, thinking, etc). ERP consists of a variety of cognitive function and related components. Including early composition, mismatch negativity (MMN), N2 family, P3 family, and other related components of language processing. These components are closely related to human cognitive function,the research of ERP can lead to a deeper understanding of cognitive function of human brains and has important application value of forensic medicine.
ABSTRACT
OBJECTIVE: Event-related potentials(ERPs) are electrical changes recorded at the surface of the scalp in response to stimulus presentation, and their latency and amplitude change according to cognitive processes. Through past studies of the auditory ERP in schizophrenia, the P300 has been reported to be statistically smaller and delayed in schizophrenia than comparison groups. However, studies of the visual ERP have not been systematically examined. The present study was designed to investigate the visual P300 in patients with schizophrenia and normal controls and to compare the pattern of P300 between them. METHODS: The subjects were composed of patients(N=22) with schizophrenia by DSM-IV and normal controls(N=22). The visual ERPs were measured by the visual continuous performance test. P300 amplitude and latency measured on 5 scalp electrodes(Fz, Cz, Pz, T7, T8) were compared between patients and controls. RESULTS: The P300 latencies measured on Fz, Cz, Pz, and T7 electrodes were significantly longer in patients than controls(p<0.05). The P300 amplitudes in patients were smaller than controls. However, the difference between them was not statistically significant. CONCLUSION: Analysis of the visual ERPs showed that the P300 latency is significantly delayed and the P300 amplitude is slightly smaller in patients than controls. These results are similar to established studies of the auditory P300 in schizophrenia.