NEUROPSYCHOLOGICAL CORRELATES OF SUSTAINED ATTENTION IN SCHIZOPHRENIA

We employed a simple and relatively undemanding task of monotone count ing for the assessment of sustained attention in schizophrenic patient s. The monotone counting task has been validated neuropsychologically and is particularly sensitive to right prefrontal lesions. We compared the performance of schizophrenic patients with age- and education-mat ched controls. We then explored the extent to which a range of commonl y employed neuropsychological tasks in schizophrenia research are rela ted to attentional impairment as measured in this way. Monotone counti ng performance was found to be correlated with digit span (WAIS-R-HK), information (WAIS-R-HK), comprehension (WAIS-R-HK), logical memory (i mmediate recall) (Weschler Memory Scale, WMS), and visual reproduction (WMS). Multiple regression analysis also identified visual reproducti on, digit span and comprehension as significant predictors of attentio n performance. In contrast, logical memory (delay recall) (WMS), simil arity (WAIS-R-HK), semantic fluency, and Wisconsin Card Sorting Test ( perseverative errors) were not correlated with attention. In addition, no significant correlation between sustained attention and symptoms w as found. These findings are discussed in the context of a weakly modu lar cognitive system where attentional impairment may contribute selec tively to a range of other cognitive deficits.