Neuropsychological correlates of the PANSS Cognitive Factor.

OBJECTIVE: Factor analytic studies of the Positive and Negative Syndrome Scale (PANSS) have consistently isolated a factor that is frequently labeled as 'cognitive'. The present study sought to further explore the factor by examining the relationships between 4 versions of the cognitive factor and a set of neuropsychological tests. METHOD: Thirty-seven inpatients diagnosed with schizophrenia or schizoaffective disorder were assessed with the PANSS and neuropsychological measures. RESULTS: Verbal intelligence and verbal memory were found to be most closely associated with cognitive factor scores. A global rating of illness severity showed greater relationships to cognitive variables than any cognitive factor. CONCLUSIONS: The PANSS cognitive factor may reflect verbal ability and memory, but is not sufficiently comprehensive to be considered as a replacement for direct assessment of cognitive functioning.

Donepezil in schizophrenia--is it helpful? An experimental design case study.

OBJECTIVE: To assess the clinical and cognitive effects of adding donepezil, a reversible acetylcholinesterase inhibitor, to the risperidone treatment of a high functioning stable out-patient with schizophrenia. METHOD: Case study using an experimental ABAB design. Assessments were completed objectively by standardized neuropsychological tests and clinical rating scales and subjectively with visual analogue scales. RESULTS: Strong improvements attributable to donepezil were found for verbal fluency and the patient's subjective response. No adverse changes were noted in psychiatric symptoms or side effects. CONCLUSION: Cholinergic enhancement as an adjunctive treatment in schizophrenia should be explored in larger controlled trials.