Increased automatic spreading of activation in thought-disordered schizophrenic patients

Area of Science:

• Cognitive Psychology
• Psychiatry
• Neuroscience

Background:

• Conflicting findings exist regarding semantic priming in schizophrenia, particularly concerning formal thought disorder (TD).
• Some studies suggest enhanced cognitive spreading of activation in schizophrenia patients with TD, while others fail to replicate this.
• Resolving these ambiguities is crucial for understanding the cognitive underpinnings of schizophrenia.

Purpose of the Study:

• To investigate semantic priming effects in schizophrenia patients with and without formal thought disorder (TD).
• To clarify the relationship between TD and cognitive spreading of activation.
• To test the validity of the spreading activation model in schizophrenia.

Main Methods:

• A semantic priming task using word pronunciation was administered to 32 schizophrenia patients (12 with TD, 20 without TD) and 65 healthy controls.
• Participants were compared across neutral and unrelated baseline conditions.
• Formal thought disorder was assessed using the PANADSS criteria.

Main Results:

• Patients with formal thought disorder (TD) exhibited significantly greater indirect semantic priming effects than non-TD patients and healthy controls.
• This hyper-priming effect was consistent across different baseline conditions.
• Confounding variables like illness duration, neuroleptic dosage, and psychomotor slowness did not influence the priming effect.

Conclusions:

• The findings strengthen the spreading activation model of formal thought disorder.
• Hyper-priming in schizophrenia is not exclusive to lexical decision tasks.
• The study highlights the importance of considering formal thought disorder in understanding cognitive deficits in schizophrenia.