The linguistic signature of hallucinated voice talk in schizophrenia

Very few studies have investigated the formal linguistic aspects of auditory verbal hallucinations (AVHs), though speech is a defining aspect of AVHs. Hallucinated speech heard by 19 patients with schizophrenia and highly frequent voices was obtained online, as and when they spoke, and annotated for pre-selected linguistic variables. Results showed that, consistently across the sample, (i) the grammatical first Person was significantly less represented than both second and third person, and often absent altogether; (ii) overwhelmingly, isolated clauses with no grammatical connectivity (parataxis) were produced, as compared with subordinations, coordinations, and adjunctions; (iii) in all participants except one, virtually no noun phrases (NPs) were anaphoric ones, back-referring to previous NPs, illustrating again a lack of connectivity across utterances. (vi) Sentence-level content was largely personal rather than impersonal, and in impersonal utterances, it was generally vague. (v) Formal syntactic errors were consistently nearly absent, as were semantic level errors such as paraphasias. Voice talk was not generally stereotyped. These results indicate that, despite a certain amount of individual variation, there is a distinctive linguistic profile to voice speech, which constrains theories of AVHs and their neurocognitive basis.