Functional mechanisms underlying impaired recognition memory and conscious awareness in patients with schizophrenia.

Abstract

EPISODIC MEMORY is a memory for personal events. Its main characteristic is its dependence on autonoetic awareness, ie, the kind of awareness that is known to normal subjects who consciously recollect these events by reliving them mentally.^1,2 In contrast, noetic awareness corresponds to the knowledge that an event occurred but without any conscious recollection; it is based on feelings of familiarity. A recent investigation showed that schizophrenia impairs episodic memory in its critical feature, ie, autonoetic awareness.³ It used an experiential approach to recognition memory, in which autonoetic and noetic awareness were operationally defined in terms of the "remember-know" procedure.^2,4 Subjects were asked to report their subjective state of awareness at the time they recognized each individual item. They were instructed to make a "remember" response if recognition was accompanied by conscious recollection (autonoetic awareness) or a "know" response if recognition was associated with feelings of familiarity (noetic awareness). Remember, but not know, responses were lower in patients with schizophrenia than in normal subjects.