Lower speech connectedness linked to incidence of psychosis in people at clinical high risk
Spencer TJ., Thompson B., Oliver D., Diederen K., Demjaha A., Weinstein S., Morgan SE., Day F., Valmaggia L., Rutigliano G., De Micheli A., Mota NB., Fusar-Poli P., McGuire P.
Background: Formal thought disorder is a cardinal feature of psychotic disorders, and is also evident in subtle forms before psychosis onset in individuals at clinical high-risk for psychosis (CHR-P). Assessing speech output or assessing expressive language with speech as the medium at this stage may be particularly useful in predicting later transition to psychosis. Method: Speech samples were acquired through administration of the Thought and Language Index (TLI) in 24 CHR-P participants, 16 people with first-episode psychosis (FEP) and 13 healthy controls. The CHR-P individuals were then followed clinically for a mean of 7 years (s.d. = 1.5) to determine if they transitioned to psychosis. Non-semantic speech graph analysis was used to assess the connectedness of transcribed speech in all groups. Results: Speech was significantly more disconnected in the FEP group than in both healthy controls (p