Can verbalization remedy the theory of mind deficit in schizophrenia?

Several studies provide convincing evidence of a specific deficit in the theory of mind (ToM) in some patients with schizophrenia. This ToM deficit consists of an inability to attribute relevant mental states to others, and studies suggest it has to be regarded as functional and remediable through the use of reinforced context processing. To investigate this, the present study compares the performances of 25 schizophrenics and 25 matched controls in a task exploring ToM before and after the introduction of verbal material into the task, initially conceived as nonverbal. All the controls and half of the schizophrenic subjects who did not initially perform at the best level remediated with verbalization, while 9 of the schizophrenics exhibited no remediation. These poor performers are characterized by a longer duration of illness. The cognitive plasticity and the characteristics of patients who do/do not remediate are discussed in the light of findings obtained with the Wisconsin Card Sorting Test. The clinical implication of these results is important since they suggest that some patients would benefit from cognitive rehabilitation in terms of their ability to attribute relevant mental states to others.