Comparison of adult schizophrenics with matched normal native speakers of English as to "acceptability" of English sentences.

This study tried to make some determinations as to whether the distortions observed occasionally in a speech in chronic schizophrenics was, at root, a thought disturbance or a problem of comprehension and use of standard English speech. We compared 25 normal college students with 25 educationally matched inpatients at Camarillo State Hospital, Camarillo, California, who had been diagnosed as chronic undifferentiated schizophrenics in the judgment of sentences as being either relatively "acceptable" or "unacceptable." The sentences (from Maher's 1972 study) varied in the degree to which they violated Chomsky's selection restriction rules: animate versus inanimate, human versus animal, and concrete verus abstract. Using Tuley's comparison test, we found no significant difference between normal and schizophrenic subjects in determining sentence acceptability or in the detection of sentence rule violations. The performance of chronic schizophrenics in rating sentences as relatively ungrammatical was not significantly different from that of normals. In addition, schizophrenics did not turn out to be significantly less sensitive to the number and types of selection rule violations in sentences. It seems probable that distortion in thought processes, rather than inability to use the semantic and syntactic rules of English speech, might be the underlying cause of the bizarre speech patterns which occur at times in the language of schizophrenics.