Acoustic features and social cognition in schizophrenia and schizotypal personality disorder

Although prior studies have observed speech alterations in schizophrenia, minimal research has focused on this in schizotypal personality disorder (SPD), despite impairments observed in social communication and function. SPD is a disorder within the schizophrenia spectrum, but individuals are typically antipsychotic naïve and lack a history of psychiatric hospitalizations. The current study examined acoustic features extracted from an open-ended interview in individuals with schizophrenia spectrum disorders and healthy controls.

Twenty-seven individuals with SPD, 36 individuals with schizophrenia or schizoaffective disorder, and 44 healthy controls (HCs) participated in the open-ended interview. Assessments included a structured diagnostic interview, clinical-symptom severity ratings, and social cognition tasks. Acoustic features of interest were extracted from audio recordings of the interviews using automated methods.

Individuals with schizophrenia demonstrated alterations in articulatory control, spectral stability, and temporal coordination compared to individuals with SPD and HCs. The SPD group exhibited similar acoustic features to HCs. Within the clinical groups combined, lower acoustic features were associated with greater negative symptom severity and poorer social cognition.

Results suggest that computerized analysis of acoustic alterations in the schizophrenia spectrum may aid in identifying subtle differences in speech that are related to symptom severity and social cognition. This study provides initial evidence to suggest that individuals with SPD are spared the acoustic speech alterations seen in schizophrenia, but future research is needed to examine these features in larger samples and in a variety of speech tasks.