The existence of small numbers of schizophrenia patients with superior ability in specific cognitive domains is implied by meta-analytic evidence as well as by occasional empirical reports. The authors identified 25 patients with superior (i.e., > or =90th percentile) ability on the Vocabulary subtest of the Wechsler Adult Intelligence Scale 3rd edition (Wechsler, 1997). These cognitively advantaged patients were compared with 22 healthy participants performing at the superior level and with 126 schizophrenia patients and 50 healthy participants scoring below the superior range. Verbally superior schizophrenia patients and verbally superior healthy participants had similar cognitive profiles and life skills performance, but diverged markedly in terms of independent "real-world" functioning. Verbally superior patients significantly outperformed more typical patients in other aspects of cognitive performance, life skills, and support requirements. However, severity of positive and negative symptoms was equivalent in the patient groups. Detailed biobehavioral study of cognitively exceptional patients may offer new insights into mechanisms mediating psychotic disorders.

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Measures of functional competence have been introduced to supplement standard cognitive and neuropsychological evaluations in schizophrenia research and practice. Functional competence comprises skills and abilities that are more relevant to daily life and community adjustment. However, it is unclear whether relevance translates into significantly enhanced prediction of real-world outcomes. The aim of this study was to assess the specific contribution of functional competence in predicting a key aspect of real-world outcome in schizophrenia: community independence. Demographic, clinical, cognitive, and functional competence data were obtained from 127 patients with schizophrenia or schizoaffective disorder and used to predict community independence concurrently and longitudinally after 10 months. Hierarchical regression analyses indicated that demographic, clinical, and cognitive predictors accounted jointly for 35%-38% of the variance in community independence across assessment points. Functional competence data failed to add significantly to this validity. Considered separately from demographic and clinical predictors, cognitive and functional competence data accounted for significant amounts of outcome variance. However, the addition of functional competence to standard cognitive test data yielded a significant increase in validity only for concurrent and not for longitudinal prediction of community independence. The specific real-world validity of functional competence is modest, yielding information that is largely redundant with standard cognitive performance.

Objective: Although impaired general intellectual ability is a prevalent feature in schizophrenia, patterns suggesting preserved, deteriorated, and premorbidly impaired intellect have also been identified. The main purpose of this investigation was to examine the clinical, cognitive, and neuroanatomical characteristics of these intellectual subtypes, and to establish the value and validity of this approach for reducing the heterogeneity of schizophrenia. Methods: A total of 71 patients with a diagnosis of schizophrenia or schizoaffective disorder and 66 healthy controls were assessed. A 'preserved' performance pattern (n=29) was defined by average-range estimated premorbid and current IQ with no evidence of decline (premorbid-current IQ difference <10 points). A 'deteriorated' pattern (n=14) was defined by a difference between estimated premorbid and current IQ estimates of 10 points or more. A 'premorbidly impaired' pattern (n=14) was defined by below average estimated premorbid and current IQ and no evidence of decline greater than 10 points. The groups were compared on demographic,