Self-monitoring enhances Wisconsin Card Sorting Test performance in patients with schizophrenia: Performance is improved by simply asking patients toverbalize their sorting strategy

Patients with schizophrenia have Wisconsin Card Sorting Test (WCST) deficit s, which are commonly interpreted as reflecting frontal cortex-based execut ive dysfunction. One means of assessing the refractoriness of frontal-execu tive impairment is to utilize a training or modification strategy to improv e WCST performance. In this study, 73 patients with schizophrenia were assi gned to 1 of 2 groups. Group 1 received the standard WCST instructions for 64 cards (Condition 1). For the second 64-card deck, the patients were aske d to verbalize the reason that they placed the card where they did after ea ch sort (Condition 2), Group 2 received this modified instruction 1st (Cond ition 1) and then the standard instructions for the second deck (Condition 2). A group of normal comparison participants was also tested using standar d instructions alone. Group 2 committed significantly fewer perseverative r esponses than did Group 1. Furthermore, there was no significant difference between Group 2 (Condition 1) and the normal participants. Group 1's perfo rmance improved when patients were exposed to the modified instructions (Co ndition 2). Additionally, poor premorbid factors and disorganized symptoms were associated with decreased benefit from the modified instructions acros s both groups. Cumulatively, these data suggest that a simple instruction m ay enhance executive function and impact WCST performance in patients with schizophrenia.