Syntactic complexity and negative symptoms in first onset schizophrenia.

This paper compares the syntactic features of three groups of subjects: first onset schizophrenics with negative symptoms (n=17); with no negative symptoms (n=18); and nonpsychiatric controls (n=16). The speech of schizophrenic subjects contained more syntactically and semantically deviant sentences. The negative symptom group produced shorter sentences that contained lower levels of clausal embedding. Most of these differences were related to group differences in social class, attentional deficits in the schizophrenic group, or collinearity between sentence length and clausal complexity. Despite this, the difference in clausal complexity persisted after the effects of these confounding variables had been removed. This indicates that reduced syntactic complexity is an important feature of the speech of patients in whom negative symptoms are prominent. The significance of this finding is discussed in relation to recent theories of schizophrenia.