Auditory P300 abnormalities in Filipino patients with schizophrenia and their siblings

ABSTRACT

OBJECTIVES: The goal of this study is to measure the auditory Event Related Potentials in Filipino patients with schizophrenia, their siblings and comparing them with normal controls. Specifically the P300 amplitude and latency measurements of schizophrenic patients would also be correlated to sociodemographic variables such as age, duration of illness and positive and negative symptoms of schizophrenia.METHODOLOGY: Patients with schizophrenia after consenting to participate in the study were screened using the Positive and Negative Symptom Scale. The auditory event related potentials (ERP) of the parietal electrode of these patients and their siblings as well as a control group of healthy individuals from the community were measured and compared.RESULTS: Comparison of P300 parameters among 20 patients with schizophrenia, 20 siblings and 20 controls using ANOVA showed that the P300 amplitude of schizophrenic patients was markedly reduced compared with the other 2 groups. P300 latency values were markedly prolonged in both schizophrenia and their siblings when compared to the control group. Analysis of the data revealed that P300 latency had a positive correlation with the duration of positive and negative symptoms. There was also an inverse correlation with positive symptomatology.CONCLUSION: There was a decreased P300 amplitude and prolonged P300 latency in Filipino Schizophrenic patients. P300 parameters in schizophrenic patients were correlated to age, duration of symptoms and positive and negative symptoms.