Inhibition Of Return In Schizophrenia And Event-related Potential Study

Part I Behavioral study of the simple discrimination and localization taskObjective:The present study was to examine and quantify different patterns of inhibition of return(IOR) with simple discrimination and localization task in schizophrenia patients and healthy controls, and whether it was influenced by the course of illness and medication. Methods:Twenty one patients with first episode schizophrenia(FES), twenty one patients with chronic schizophrenia(CS), and twenty one healthy controls(HC) were recruited in the study according to the inclusive and exclusive criteria. All subjects went through simple discrimination and localization task with six stimulus onset asynchrony(SOA) intervals (300ms,700ms,1200ms,1300ms, 1500ms and 2000ms) at three time points (baseline,6 weeks after medication,8 weeks after medication), and record the behavioral data(reaction time, accute rate and the effect of IOR). Results:Compared between three groups, the reaction time of CS was longer than that of FES and HC, the accurate rate of CS was lower than that of FES and HC. Compared between three time points, all of the data above was improved after medication. But the difference of magnitude of IOR across the three groups and time points were not found to be statistically significant. Conclusion:In the simple discrimination and localization task with exogenous non-informative peripheral and central cue, the schizophrenic patients response more slowly than healthy controls, and can be improved by medication.Partâ…¡Behavioral and ERP study of the simple detection task1. Behavioral study of the simple detection task Objective:The present study was to examine and quantify different patterns of IOR with simple detection task in schizophrenia patients and healthy controls, and whether it was influenced by the course of illness and medication. Methods:Twenty one patients with FES, twenty one patients with CS, and twenty one HC were recruited in the study according to the inclusive and exclusive criteria. All subjects went through simple detection task with three SOA intervals (350ms,700ms,1200ms) at two time points (baseline,6 weeks after medication), and record the behavioral data(reaction time, accute rate and the effect of IOR). Results:Compared between three groups, the reaction time of CS was longer than that of FES and HC, the accurate rate of CS was lower than that of FES and HC. Compared between two time points, all of the data above was improved after medication. The difference of magnitude of IOR between HC and patients(FES and CS) were found to be statistically significant. Moreover, the difference were not found to be changed by medication. Conclusion:In the simple detection task with exogenous non-informative peripheral and central cue, the schizophrenia patients response more slowly and inaccurately than healthy controls, and can be improved by medication. IOR effects were induced in both the patients and controls, but the magnitude of IOR on ERP early components were not infulenced by illness duaration and medication.2. ERP study of the simple detection taskObjective:The present study was to elucidate different performance of IOR on the early ERP perceptive components (P1 and N1) with simple detection task in schizophrenia patients and healthy controls, and whether it was influenced by the course of illness and medication. Methods:Twenty one patients with FES, twenty one patients with CS, and twenty one HC were recruited in the study according to the inclusive and exclusive criteria. All subjects went through simple detection task with three SOA intervals (350ms,700ms,1200ms) at two time points (baseline,6 weeks after medication), and record the ERP data. Results:Compared between three groups, the magnitude of P1 and N1 were not found to be statistically significant, but the latency of CS was longer than that of FES and HC. Compared between two time points, all of the data above was not found to be different.Conclusion:In the simple detection task with exogenous non-informative peripheral and central cue, IOR effects were induced in both the patients and controls, but the effect of IOR were not changed after medication.Conclusion1. In the simple discrimination, localization and detection task with exogenous non-informative peripheral and central cue, the schizophrenia patients response more slowly and inaccurately than healthy controls. Moreover, all of these can be improved by medication.2. In the simple discrimination, localization and detection task with exogenous non-informative peripheral and central cue, IOR effects were induced in both the patients and controls. However, in the simple detection task the magnitude of IOR were not influenced by illness duaration and medication.3. In the simple detection task with exogenous non-informative peripheral and central cue, IOR effects were induced in both the patients and controls, but the effect of IOR on ERP early perceptive components(P1 and N1) were not changed after medication.