Korean Journal of Biological Psychiatry

Objectives : This study aimed to identify the differences and the profiles of cognitive deficits in remitted patients with schizophrenia and first-degree relatives of schizophrenic probands.

Methods : A total of 26 remitted states of schizophrenia patients were included in the study and the same number of unaffected first-degree relatives of schizophrenic probands and healthy controls were matched for age, sex, years of education. Cognitive function of all participants was measured by using the Digit span test, the Continuous performance test, the Rey auditory & visual learning test, the Complex figure test, the Verbal fluency test, the Wisconsin card sorting test and the Finger tapping test. The effects of subsyndromal symptomatology and general intelligence score were controlled.

Results : Schizophrenia patients' group showed more significant impairment than other groups in verbal memory (learning, immediate recall, delayed recall), visual memory (copy, immediate recall, delayed recall) and cognitive flexibility domains. The family group and the patient group commonly performed significantly worse than healthy controls in working memory and verbal fluency (category) tests. There were no differences in sustained attention, psychomotor performance.

Conclusions : Our research shows that the deficit in working memory and verbal fluency could be strong candidates of endophenotypic marker in schizophrenia.

Keywords Schizophrenia;Neurocognitive function;First-degree relatives;Endophenotype.