Display visual angle and attentional scanpaths on the span of apprehension task in schizophrenia

The effect of display visual angle on span of apprehension (SOA) task performance was investigated in patients with schizophrenia and nonpsychiatric individuals. Narrow and wide visual-angle presentations of 3- and 10-letter arrays were compared. Detection rates were significantly higher with narrow than wide visual angle for nonpsychiatric individuals; the performance of those with schizophrenia was stable across visual-angle conditions. Patients with schizophrenia were best discriminated from nonpsychiatric individuals in the narrow-angle, 10-letter condition. Scanpath analyses, which were based on the pattern of detection rates across different target quadrant locations, suggested that the patients with schizophrenia used a similar number and path of covert scan moves as did the controls. Hypotheses are discussed regarding which of the multiple cognitive processes tapped by the SOA task may be impaired in schizophrenia.