Neural correlates of sleep, stress, and selective memory consolidation

The sleeping brain often preferentially consolidates salient (e.g. emotional, novel, rewarding) memories. When a stressful event occurs in proximity to a memory task, recently learned information tends to be prioritized for consolidation (behavioral tagging). Evidence for tagging emerges from neuroimaging studies, which show altered patterns of neural activity and connectivity in memory networks after stress and sleep. Furthermore, recent studies suggest that stress and sleep interact to promote selective consolidation. In this paper, we describe evidence for stress-related and sleep-related changes in the brain and behavior, with an emphasis on emotionally salient memories. We propose that stress and subsequent SWS-REM sleep cycles facilitate functional connectivity and promote the selective consolidation of salient memories and describe recent evidence to support this theory.