Referential failures and affective reactivity of language in schizophrenia and unipolar depression

Reference failures, and their increase in affectively negative conditions (known as affective reactivity of speech), are more frequently observed in schizophrenia patients than in normal controls, but no information is available comparing schizophrenia with depression, ie, a mental disorder closely linked to the concept of affective reactivity. To address this gap in the literature, the present study compared 24 schizophrenia inpatients, 21 unipolar depression inpatients and 21 normal controls. Two 10-minute conversational speech samples (1 on negative and 1 on positive memories) were collected from each patient. The transcripts of the audiotaped interviews were analyzed blindly for frequencies of 6 types of referential failures, employing the Communication Disturbances Index, adapted for use with Italian. The schizophrenia patients made more frequent total reference failures and, specifically, more missing information references than the depression patients. The depression patients made more frequent reference failures than the normal controls, overall, and on most of the specific types of failures. Affective reactivity of speech was observed only for the schizophrenia sample and was greatest for missing information references. This study supports the viability of reference failure analysis as a measure of communication disturbance in a language other than English. The findings indicate that schizophrenia and depression both are associated with high levels of referential failures but that affective reactivity of speech is present only in schizophrenia and not in depression.