Communication disturbances and family psychiatric history in parents of schizophrenic patients.

Parents of schizophrenic patients have demonstrated subtle disturbances of thought, language, and communication. The etiologic relevance of these disturbances is not clear. This study assessed levels of referential communication disturbance in the "natural speech" of schizophrenic patients, nonschizophrenic parents of patients, and control subjects matched to the patients' parents and tested for associations of communication disturbances in parents with family history of psychosis and with schizotypy scale scores. The speech of the patients' parents as a group contained high frequencies of referential failures. Those parents with first-degree family histories of psychosis and/or high schizotypy scale scores made more frequent referential failures than the rest of the parents. Family history was particularly highly associated with failures involving language structural breakdown. The results of this study suggest that referential disturbances in parents of patients may be related to genetic liability in the parents. However, such an effect does not appear to account fully for the sizable differences between parents and controls in levels of communication disturbance.