Chronic/negative and acute/positive schizophrenia and attention deficits

Schizophrenia is a psychiatric disorder that impairs several intellectual functions, including attention processes. To investigate attention deficit in a group of patients with schizophrenia. Method: Thirty patients with schizophrenia hospitalized in three psychiatric wards in Shiraz and Isfahan and 30 normal healthy subjects matched for age, gender and years of education underwent the following tests: A computerized Continuous Performance Test [CPT], Stroop color-word test and Wisconsin Card Sorting [WCS] test. In the tests performed, patients with schizophrenia preformed poorer than control subjects. The acute/chronic classification did not predict differences in attention processes among subtypes of schizophrenia, while positive/negative classification predicted differences observed among the patient groups. The subtypes of schizophrenia [paranoid, undifferentiated and residual] had the same performance in CPT, while they were significantly different in error scores of [WCS] and reaction time in response to Stroop stimuli in incongruent color-word condition. The paranoid patients preformed better in contrast to other subtypes on attention related tasks. The results of the present study suggest that CPT is a valuable test for differentiation of schizophrenia disorder in general, while Stroop test and WCS may have better diagnostic value for differentiating subtypes of the disorder