Functional mechanisms underlying impaired recognition memory and consciousawareness in patients with schizophrenia

Background: Schizophrenia impairs episodic memory in its critical feature, autonoetic awareness, ie, the type of awareness that is characterized by me ntally reliving events from one's personal past. It spares noetic awareness , another form of awareness based on feelings of familiarity. We investigat ed the hypothesis that the impairment of autonoetic awareness is related to defective information that binds together separate aspects of events. Methods: An experiential approach to recognition memory was used. Twenty-fi ve patients with schizophrenia and 25 normal subjects performed or watched actions consisting of pairing objects. Then, they had to recognize pairs of objects and who paired them (source recognition). Subjects were also asked to provide a "remember" (autonoetic awareness) or a "know" (noetic awarene ss) response according to their subjective state at the time they recognize d each pair of objects and each source. Results: Patients exhibited an impaired recognition memory. When actions we re observed, recognition of pairs of objects, but not of source, was no bet ter than chance. There was a reduction in frequency of autonoetic awareness , its consistency throughout recognition of objects and source, and its rel ationship to source discrimination accuracy. Recognition was based largely on noetic awareness. Conclusions: Patients with schizophrenia are unable to link the separate as pects of events into a cohesive, memorable, and distinctive whole. The coro llary of this defective relational binding is a quantitative and qualitativ e impairment of autonoetic awareness.