Cognitive dysfunction are considered core deficit in schizophrenia. The cognitive domains more impaired are attention, verbal memory and executive function. The study of this dysfunction can be used to understand the etiology and pathogenesis of schizophrenia. Cognitive deficits have frequently been reported in the unaffected first degree relatives of schizophrenia patients.

To investigate whether cognitive deficits found in patients with schizophrenia are also found in non-affected relatives.

We compared schizophrenic patients (n=31), first-degree relatives (26) and normal controls (n=22). The neurocognitive domains assessed included executive functioning, verbal memory, attention and language function.

Schizophrenic patients demonstrated cognitive impairments across most domains compared with control subjects. First degree relatives were significantly impaired compared with control subjects only in attention and verbal memory; no significantly differences were observed in language function. The relatives of schizophrenia patients have impairments in memory function and attention compared to controls but they are less impaired compared to schizophrenic patients. The schizophrenic patients performed on executives tasks significantly worse than either their relatives or normal subjects, but unaffected relatives did not differ from controls.

Cognitive deficits found in patients with schizophrenia are also found in non-affected relatives. Adult relatives of schizophrenic patients have wide but not severe cognitive impairments. The largest deficits were observed for verbal memory and attention.