Objectives:P300 is a cognitive event-related potential (ERP) elicited by relevant stimuli. The P300 component (amplitude and latency) is consistently reduced in patients with schizophrenia during stimulus discriminate task. This study was designed to evaluate the clinical availability of P300 latency in patients with schizophrenia.
Methods:To elicit P300, 2-stimulus auditory and visual oddball paradigms were employed for patients with schizophrenia (N= 12) and normal controls (N=12). The 2-stimulus auditory oddball paradigm was composed of standard tone (1000 Hz, 75 dB, 80%) and target tone (2000 Hz, 75 dB, 20%).
Results:P300 amplitude was not smaller in patients with schizophrenia across midline electrodes (F=2.7, p=0.11). There was no interaction between subject groups and electrode (F=0.7, p>0.4). The P300 latency showed delayed trend in patients with schizophrenia across midline electrodes (F=3.6, p=0.07) and there was no interaction between subject groups and midline electrodes (F=1.1, p>0.2).
Conclusion:Even though P300 amplitude in patients with schizophrenia was not smaller, the P300 latency could be delayed. Thus, P300 latency might be used as a kind of biological marker for exploring the patients with schizophrenia. (Schizophrenia Clinics 2005;8:25-29) |