Memory consolidation and reconsolidation: what is the role of sleep?

Trends in Neurosciences
Volume 28, Issue 8, August 2005, Pages 408-415
Copyright © 2005 Elsevier Ltd All rights reserved.

Memory consolidation and reconsolidation: what is the role of sleep?

Robert StickgoldE-mail The Corresponding Author and Matthew P. WalkerE-mail The Corresponding Author

Center for Sleep and Cognition, Department of Psychiatry, Harvard Medical School, Beth Israel Deaconess Medical Center E/FD 861, 330 Brookline Avenue, Boston MA 02215, USA

Available online 23 June 2005.

Memory consolidation and reconsolidation reflect molecular, cellular and systems-level processes that convert labile memory representations into more permanent ones, available for continued reactivation and recall over extended periods of time. Here, we discuss the complexities of consolidation and reconsolidation, and suggest they should be viewed not as all-or-none phenomena, but as a continuing series of biological adjustments that enhance both the efficiency and the utility of stored memories over time and in response to changing needs of the organism. As such, consolidation and reconsolidation might be better thought of as memory organization and reorganization. A rapidly growing body of evidence suggests that many of these processes are optimally engaged during sleep.

Article Outline

Introduction
Memory systems and brain states
Memory stages: consolidation and reconsolidation
Sleep and memory consolidation
Sleep-dependent plasticity
Reconsolidation

Time course of reconsolidation
Sleep and reconsolidation

Final comments
Acknowledgements
References