Selective, sustained, and shift in attention in patients with diagnoses of schizophrenia

Attentional deficits are a prominent aspect of cognitive dysfunction in schizophrenia. The present study was designed to investigate attention deficit in a group of patients with diagnosis of schizophrenia. According to the segmental set theory suggested by Hogarty and Flesher, three aspects of attention problems, selective, sustained, and shift in attention, were studied. The 30 patients hospitalized on three psychiatric wards at Shiraz and Isfahan and 30 normal healthy subjects matched for age, sex, and years of education were administered a computerized Continuous Performance Test, Stroop Color-word Test, and Wisconsin Card Sorting test. Analysis showed patients performed more poorly than control subjects on measured aspects of attention. The acute/chronic classification did not predict differences in attention scores between subtypes of schizophrenia, while the positive/negative classification did. Paranoid, undifferentiated, and residual groups by subtypes of schizophrenia showed similar performance on the Continuous Performance Test, but were significantly different on errors on the Wisconsin Card Sorting test and on reaction time to Stroop stimuli in the incongruent color-word condition. Patients with paranoid diagnosis performed better than other subtypes on these tasks. Present results suggest that the Continuous Performance Test is valuable for differentiating of schizophrenia spectrum disorder, while scores on Stroop and Wisconsin card sorting may have better diagnostic value for differentiating subtypes of the disorder.