Study On Characteristics Of Source Monitoring In Patients With Schizophrenia

Objective Schizophrenia is a disorder associated with symptoms such as hallucinations, delusions, and thought disorder. Some of these symptoms (e.g., hallucinations and Schneiderian delusions) are considered to be representative of a disorder of "self," involving difficulty in discriminating between information that was self-generated and that originating from others. Source-monitoring is a complex set of cognitive processes that involves discriminating the source of an event. These events may be internally generated (such as in imagination) or externally generated (such as something seen or heard).People with psychosis may have difficulties with many aspects of source-monitoring.We used a paradigm that engages verbal self-monitoring to investigate this theory in patients with schizophrenia.Methods The diagnoses were made according to international Statistical Classification of diseases and related health problems,Tenth Edition (ICD-10) criteria.Total 50 patients with schizophrenia and 26 healthy control group subjects matched for age, gender,education were enrolled in the study.Useing PANSS scales assess patients’ psychiatric symptoms.Then all subjects take task source monitoring paradiam.Results 1:There are significant differences between two patient groups and control group on ACSIM (P<0.01), the control group is better than Sch-AVH group (P<0.01) and Sch-nonAVH group (P<0.01),but not between Sch-AVH group and Sch-nonAVH(P>0.05).2:The mistake attributing imagined voices to heard voices have significant differences between three groups (P<0.01), the control group is better than Sch-AVH group (P<0.01) and Sch-nonAVH group (P<0.01),but not between Sch-AVH group and Sch-nonAVH group (P>0.05); 3:There are significant differences about RT between three groups (P<0.01), the control group is better than Sch-AVH group (P<0.01) and Sch-nonAVH group (P<0.01),but not between Sch-AVH group and Sch-nonAVH group (P>0.05).4:There is a significant negative correlation between PANSS positive subscale scores and ACSIM scores (r=-0.35,P=0.02) in Sch-AVH group.Remaining correlations were very weak and did not reach significance.Conclusion Source monitoring is impaired in patients with schizophrenia, some of the symptoms (such as delusions, hallucinations) may be related to a failure of reality discrimination,whereby inner speech is mistaken for an external event and misattributed to an external source.