Abstract
Cognitive dysfunction has been described as a hallmark feature of schizophrenia since the first descriptions of the illness. Kraepelin described a number of features of the disorder that he thought reflected impairments in cognition and attention. He also speculated that cognitive impairments were mediated by neurobiologic dysfunction, specifically impairments in the functions of the frontal lobe. Since Kraepelin’s time, there have been many changes in the general conceptions of schizophrenia, including ideas regarding the status and importance of cognitive impairment in the illness. Due to increased sophistication of neuropsychologic assessment and neuroimaging techniques, cognitive impairment has again has risen to the forefront of importance in terms of theories regarding the etiology and treatment of schizophrenia.