Cognitive impairment has emerged as an important new target in schizophrenia therapeutics in light of evidence that cognitive deficits are critically related to the functional of disability that is characteristic of the illness. Evidence is briefly reviewed supporting the idea that the cognitive impairment in schizophrenia is an attractive target for therapeutic intervention including: (1) there is a characteristic pattern of cognitive deficits that occur with very high frequency; (2) the deficits are relatively stable over time; and (3) cognitive deficits are relatively independent of the symptomatic manifestations of the illness. Thus, cognitive impairment appears to be a well-defined, reliable and distinct dimension of the illness.

Davidson, M, Keefe RSE. Cognitive impairment as a target for pharmacological treatment in schizophrenia. Schizophrenia Research, 1995; 17(1):123-129.