Examination and Comparison of Cognitive and Executive Functions in Patients with Schizophrenia and Bipolar Disorders

Schizophrenia and bipolar disorders are associated with impaired cognitive and executive functions. Cognitive and executive profile of these two disorders is similar. However, cognitive and executive deficits in these patients may follow different paths. The purpose of the present study is to examination and comparison of different paths of cognitive and executive function in patients with schizophrenia and bipolar disorders. This was a descriptive study on patients with schizophrenia and bipolar disorders from 2016 to 2017. Thirty-four patients with schizophrenia, 52 patients with bipolar disorder, and 72 healthy individuals participated in the present study. This research was performed in Kargarnejad psychiatric hospital located in Kashan City, Iran. In this study, Positive and Negative Symptom Scale (PANSS), Young Mania Rating Scale (YMRS), Beck Depression Inventory-II (BDI-II), Tower of London task, Wisconsin card sorting task, Trial Making Test (TMT), and Four-Choice reaction time test (Four-Choice) were used. The MANOVA test showed a significant difference between the schizophrenia, bipolar disorder, and healthy groups in all scales of cognitive and executive functions. Altogether, performance of patients with schizophrenia in cognitive and executive functions were better than those with bipolar disorder; but schizophrenia and bipolar disorder groups have weaker performance than healthy persons (P < 0.001). This study show that cognitive and executive functions are destructed in schizophrenia and bipolar disorders, and they have weaker cognitive and executive functions than healthy controls. Moreover, cognitive and executive functions in patients with bipolar disorder are weaker than patients with schizophrenia, and follow different paths from schizophrenia.