Neuropsychological abnormalities in schizophrenia and major mood disorders: similarities and differences.

The past 20 years have been witness to a growing knowledge base of research highlighting the critical importance of cognition in understanding functional status and outcome in schizophrenia. This work has led to an increased emphasis on identifying and evaluating treatments that enhance cognition in schizophrenia, with the hope that this would translate into a better quality of life and improved outcome for patients. At the same time, this research has raised new questions about the specificity of cognitive impairments to schizophrenia and the degree to which similar cognitive impairments may be present in other disorders that can involve psychotic symptoms (eg, schizoaffective disorder, bipolar disorder, and psychotic major depression). This article provides a brief overview of work comparing cognitive function across the nonaffective and affective psychoses and highlights areas of similarity and dissimilarity in the role cognition plays in these disorders.