Dreaming of a learning task is associated with enhanced memory consolidation: Replication in an overnight sleep study.

Dreaming about a spatial learning task during sleep predicts improved performance the next morning. In an overnight study, people trained on a virtual maze navigation task reported dreams from all sleep phases that reflected the task. Unambiguous representation of the task in dream content was associated with better next-morning performance. These findings align with models of memory consolidation that propose memory traces are reactivated during sleep, and replicate earlier work showing that dreaming about a learning task during a nap predicted performance gains.

Study at a glance

Abstract

Sleep following learning benefits memory. One model attributes this effect to the iterative "reactivation" of memory traces in the sleeping brain, demonstrated in animal models. Although technical limitations prohibit using the same methods to observe memory reactivation in the human brain, the study of mental activity during sleep provides an alternative method of observing memory activation during sleep. In fact, the content of dream experience may reflect the process of memory reactivation and consolidation in the sleeping brain. In line with this hypothesis, we previously reported that dreaming about a spatial learning task during a nap strongly predicts subsequent performance improvements. Here, we replicate this observation in an overnight sleep study, for the first time demonstrating that pre-sleep training on a virtual maze navigation task is reflected in dreams reported from all phases of sleep, with unambiguous representation of the task in dream content associated with improved next-morning performance. These observations are consistent with reactivation-based models of memory consolidation in sleep, confirming our earlier finding that the cognitive-level activation of recent experience during sleep is associated with subsequent performance gains.