Impaired frontal processing during agency inferences in schizophrenia

Abstract

People generally experience themselves as the cause of outcomes following from their own actions. Such agency inferences occur fluently and are essential to social interaction. However, schizophrenia patients often experience difficulties in distinguishing their own actions from those of others. Building on recent research into the neural substrates underlying agency inferences in healthy individuals, the present study investigates how these inferences are represented on a neural level in patients with schizophrenia. Thirty-one schizophrenia patients and 31 healthy controls performed an agency inference task while functional magnetic resonance images were obtained. Participants were presented with a task wherein the relationship between their actions and the subsequent outcomes was ambiguous. They received instructions to cause specific outcomes to occur by pressing a key, but the task was designed to match or mismatch the color outcome with the participants' goal. Both groups experienced stronger agency when their goal matched (vs. mismatched) the outcome. However, region of interest analyses revealed that only controls showed the expected involvement of the medial prefrontal cortex and superior frontal gyrus, whereas in patients the agency experience was not related to brain activation. These findings are discussed in light of a hypofrontality model of schizophrenia.