Missing referents, psychotic symptoms, and discriminating the internal from the externalized

Area of Science:

• Cognitive Psychology
• Psychiatry
• Neuroscience

Background:

• Schizophrenia patients exhibit communication impairments, including speech errors like references without clear referents.
• These speech errors are hypothesized to stem from underlying cognitive deficits, potentially linked to the genetic basis of schizophrenia.

Purpose of the Study:

• To investigate the cognitive underpinnings of speech errors (references without referents) in schizophrenia.
• To examine the association between these speech errors and internal source memory performance.
• To explore the relationship between speech errors, internal source memory, and the severity of psychotic symptoms.

Main Methods:

• A sample of 110 schizophrenia/schizoaffective outpatients and 23 controls provided speech samples and completed memory tests.
• Internal source memory, immediate memory, working memory, and external source memory were assessed.
• Symptom severity, including hallucinations and delusions, was rated for all participants.

Main Results:

• Schizophrenia patients demonstrated poorer performance on memory tests compared to controls.
• Patients exhibited significantly more frequent references without referents in their speech.
• The frequency of missing referents correlated with impaired internal source memory, even after controlling for other memory functions.

Conclusions:

• Impaired internal source memory is a potential cognitive process underlying speech errors in schizophrenia.
• Shared cognitive processes may link missing referents, hallucinations, and delusions in schizophrenia.
• Findings support the role of internal source memory deficits in the communication and symptom profiles of schizophrenia.