Sleep Enhances Consolidation of Memory Traces for Complex Problem-Solving Skills

Cereb Cortex. 2022 Feb 8;32(4):653-667. doi: 10.1093/cercor/bhab216.

Abstract

Sleep consolidates memory for procedural motor skills, reflected by sleep-dependent changes in the hippocampal-striatal-cortical network. Other forms of procedural skills require the acquisition of a novel strategy to solve a problem, which recruit overlapping brain regions and specialized areas including the caudate and prefrontal cortex. Sleep preferentially benefits strategy and problem-solving skills over the accompanying motor execution movements. However, it is unclear how acquiring new strategies benefit from sleep. Here, participants performed a task requiring the execution of a sequence of movements to learn a novel cognitive strategy. Participants performed this task while undergoing fMRI before and after an interval of either a full night sleep, a daytime nap, or wakefulness. Participants also performed a motor control task, which precluded the opportunity to learn the strategy. In this way, we subtracted motor execution-related brain activations from activations specific to the strategy. The sleep and nap groups experienced greater behavioral performance improvements compared to the wake group on the strategy-based task. Following sleep, we observed enhanced activation of the caudate in addition to other regions in the hippocampal-striatal-cortical network, compared to wakefulness. This study demonstrates that sleep is a privileged time to enhance newly acquired cognitive strategies needed to solve problems.

Keywords: fMRI, memory consolidation; problem solving; procedural memory; sleep.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Hippocampus / diagnostic imaging
  • Humans
  • Learning / physiology
  • Memory Consolidation* / physiology
  • Motor Skills / physiology
  • Sleep* / physiology
  • Wakefulness / physiology