Consciousness across Sleep and Wake: Discontinuity and Continuity of Memory Experiences As a Reflection of Consolidation Processes.

The continuity hypothesis suggests that waking and dreaming mentation are connected, with emotionally salient waking experiences often appearing in dreams. However, discontinuities between waking and dreaming have been dismissed as errors or anomalies. This paper argues that disruptions of consciousness are equally common in waking cognition and that sleep-dependent memory consolidation of autobiographical experiences can explain some discontinuities in dreaming. Drawing on evidence of memory incorporation, fragmentation, and reorganization within dreams, the paper proposes that fragmentation of autobiographical and episodic memories during sleep, as part of consolidation, makes salient aspects of those memories available for retrieval isolated from their context. Thus, discontinuity in sleep is functional and normal.

Study at a glance

Abstract

The continuity hypothesis (1) posits that there is continuity, of some form, between waking and dreaming mentation. A recent body of work has provided convincing evidence for different aspects of continuity, for instance that some salient experiences from waking life seem to feature in dreams over others, with a particular role for emotional arousal as accompanying these experiences, both during waking and while asleep. However, discontinuities have been somewhat dismissed as being either a product of activation-synthesis, an error within the consciousness binding process during sleep, a methodological anomaly, or simply as yet unexplained. This paper presents an overview of discontinuity within dreaming and waking cognition, arguing that disruptions of consciousness are as common a feature of waking cognition as of dreaming cognition, and that processes of sleep-dependent memory consolidation of autobiographical experiences can in part account for some of the discontinuities of sleeping cognition in a functional way. By drawing upon evidence of the incorporation, fragmentation, and reorganization of memories within dreams, this paper proposes a model of discontinuity whereby the fragmentation of autobiographical and episodic memories during sleep, as part of the consolidation process, render salient aspects of those memories subsequently available for retrieval in isolation from their contextual features. As such discontinuity of consciousness in sleep is functional and normal.