Failures in Learning-Dependent Predictive Perception as the Key Cognitive Vulnerability to Psychosis in Schizophrenia

Abstract

Cognitive deficits present in almost all patients with schizophrenia, and account for considerable functional disability, but as typically measured in schizophrenia are unrelated to hallucinations and delusions. The absence of this relationship may be caused in part by the lack of an organizing principle of psychosis-related cognitive impairment. Most studies of cognition in schizophrenia involve standard neuropsychological tests that were devised for measuring brain injury in patients with no previous relevant illness. Human perception, thought and action—the basic elements of maintaining reality—are based upon a hierarchical process that conjoins memory and external stimuli, which we refer to as learning-dependent predictive perception. We propose that impairments in this elemental process lead to psychosis in patients with schizophrenia.