Schizophrenia impairs phonological speech production: A preliminary report

Introduction. Schizophrenia causes clinically conspicuous impairment of syntax and semantics as part of the disorganisation syndrome; however, little is known regarding its effect on the phonological stage of speech, where word meanings are resolved into speech imagery. Methods. We used a "tongue-twister" task to probe phonological speech production and its clinical associations in six schizophrenia patients and 16 controls. Results. Errors induced by phonological similarity were more common in the patients (p = .003), were positively associated with psychomotor poverty symptoms (p = .02) and negatively associated with reality distortion symptoms (p = .03). Conclusions. Our findings suggest that phonological speech production is markedly disrupted by schizophrenia. Further, this phonological abnormality is distinct from disorganisation syndrome.