Mental Imagery in First-Degree Relatives of Patients with Schizophrenia

Background: Implicit mental rotation has been studied in patients with schizophrenia; however, no research has examined it in relatives of the patients. Objectives: This study compared the performances of schizophrenia patients with their unaffected relatives to shed further light on the nature of cognitive functioning in schizophrenia relatives. Methods: We examined mental rotation in 25 schizophrenia patients, 25 of their first-degree relatives and 25 controls, using the Hand Rotation Task. In this task, the participants had to determine the laterality of hands showed in various orientations. Results: The results of this study revealed that the mean error rate of the relatives was significantly different between patients and healthy controls (all P < 0.03), ii), the mean response times of both patients and relatives were significantly slower than controls (all P < 0.004). Conclusions: These findings suggest that mental rotation may be a trait marker for schizophrenia.