Abnormal subjective experiences in schizophrenia: Its relationships with neuropsychological disturbances and frontal signs

The prevalence of abnormal subjective experiences is high in schizophrenic patients. This study starts from the hypothesis that these subjective disorders are associated with cognitive disturbances. In order to test this hypothesis a study was carried out on 40 patients who were diagnosed as suffering from schizophrenia according to RDC and DSM-III-R criteria. They were consecutively admitted due to a recrudescence of their symptomatology. Version 3 of the Frankfurt Complaint Questionnaire, adapted for Spanish by the authors, was used as an instrument for the assessment of subjective experiences. Eight patients refused to answer the questionnaire. A neuropsychological battery, including the Mini-Mental State, some subtests from the WAIS, Bender's visual-motor test, Rey's Complex Figure, and the Trail Making Test, was used. Frontal neurological signs were evaluated. The abnormal subjective experiences of schizophrenics presented a close association with neuropsychological disturbances and, to a lesser degree, of intensity with frontal neurological signs. Regression analyses by means of stepwise method and partial correlation analyses were undertaken. Many significant relationships between subjective experiences and cognitive disturbances persisted after controlling the influence of age, gender, education, lack of insight, neuroleptic doses, and biperidene doses.