Dissecting Sense of Agency in Schizophrenia: A Predictive Coding Perspective

Area of Science:

• Cognitive Neuroscience
• Psychiatry
• Clinical Psychology

Background:

• Neurocognitive processes underlying the sense of agency are frequently disrupted in schizophrenia.
• Previous studies have not fully controlled for confounding factors like temporal perception, medication, or executive functioning.

Purpose of the Study:

• To investigate the sense of agency in schizophrenia patients while controlling for potential confounding variables.
• To examine the relationship between agency disturbances, specific symptoms (delusions, hallucinations, passivity), and temporal perception biases.

Main Methods:

• Utilized the intentional binding phenomenon, an implicit measure of agency, in 30 schizophrenia patients and 30 healthy controls.
• Employed active (self-initiated action) and passive (externally controlled action) conditions to assess agency.
• Administered comprehensive neuropsychological assessments and symptom evaluations, including positive, negative, and passivity symptoms.

Main Results:

• Healthy controls exhibited the intentional binding effect, particularly with shorter action-outcome delays.
• Schizophrenia patients demonstrated an absence of the intentional binding effect.
• The observed alteration in agency was significantly moderated by temporal perception biases, hallucinations, and delusions.

Conclusions:

• This study provides novel evidence linking disturbances in the sense of agency to symptomatology and temporal perception in schizophrenia, independent of medication effects.
• Findings support a predictive coding model of the sense of agency and highlight the role of specific symptoms in agency deficits.