Attentional vulnerability indicators in schizophrenia and bipolar disorder

Visual attention and positive and negative symptoms were assessed in 59 inpatients with a relapse of schizophrenia and 3 months later during a period of relative remission. Visual attention was measured with the Continuous Performance Task (CPT) and the Span of Apprehension Task (SPAN). At follow-up schizophrenia subjects were compared on visual attention to 40 outpatients with bipolar disorder and 40 normal controls. Although symptoms improved significantly, the schizophrenia subjects' performance on the CPT and SPAN was relatively stable over time. Poor visual attention was significantly associated with high levels of negative, but not positive symptoms at the 3-month follow-up. The schizophrenia subjects had poorer visual attention than the normal controls. There were no differences between the schizophrenia and the bipolar subjects. These results offer partial support to the hypothesis that deficits in visual attention may be negative symptom-linked vulnerability indicators.