Poverty of speech in schizophrenia and depression during in-patient and post-hospital periods.

Poverty of speech, a prominent feature of the negative symptom construct in schizophrenia, was assessed longitudinally in 12 schizophrenic and 13 depressed subjects at hospital admission and about seven months after discharge in order to evaluate hypotheses concerning course and diagnostic specificity. Multiple measures of the poverty of speech construct were employed, including both clinical and quantitative indices. During the in-patient period, poverty of speech was more pronounced among depressed than schizophrenic subjects. Examination of this specific negative symptom across in-patient and follow-up evaluations indicated that poverty of speech increased among schizophrenic subjects, but remained relatively stable or declined among depressed subjects. These results suggest that the processes underlying poverty of speech may differ in schizophrenia and depression.