Waking Restfulness Can Support Memory Consolidation

Taking a short rest can result in the retention of more detailed memories, relative to being busy in the minutes following learning, new research from Heriot-Watt University indicates.

The role of sleep in memory consolidation has been well known for almost a decade. Previous research by the team showed that if we rest quietly for 10 minutes after learning something new, we retain more information.

The team’s new findings show that quiet resting after learning not only helps us to remember, it also results in the retention of more detailed memories.

Memory Reactivation

Dr. Michael Craig, the research fellow at Heriot-Watt University funded by The Alzheimer’s Society to conduct this research, said:

“Recent research suggests that the memory system strengthens weak new memories by ‘reactivating’ them, where brain activity first observed during learning automatically reappears in the minutes that follow. This appears especially true during sleep and quiet resting, when we’re not busy taking in any new sensory information. We think that quiet resting is beneficial because it is conducive to the strengthening of new memories in the brain, possibly by supporting their automatic reactivation. However, we don’t know exactly how this rest-related memory strengthening works. Specifically, it remained unknown whether quiet resting only allows us to retain more information, or whether it also helps us to retain more detailed memories.”

Dr. Craig and Dr. Michaela Dewar developed a memory test able to detect subtle differences in the fine detail of new memories. Dr. Craig explained:

“In this memory test, peoples’ ability to discriminate between ‘old’ and ‘similar’ photos provides a measure of how detailed stored memories are. If detailed memories are stored, people should notice subtle differences in similar photos, and correctly respond ‘similar’. However, if not-so detailed memories are stored, people should miss the subtle differences in similar photos, and mistake them for ‘old’ photos.

Interestingly, we found that younger adults who quietly rested in the minutes that followed the photo presentation were better at noticing subtle differences in similar photos, suggesting that these individuals stored more detailed memories, compared to those who did not rest. This new finding provide the first evidence that a brief period of quiet rest can help us to retain more detailed memories.”

The research team will now focus on what happens in the brain during rest periods, and why it has a positive effect on memory retention.

Rest-related consolidation protects the fine detail of new memories

Experimental paradigm. Participants underwent three phases: (i) encoding, (ii) delay, and (iii) testing.
Credit: Michael Craig et al., CC-BY

To do this, they are combining their new memory test with EEG recording to monitor brain activity during rest; with the aim of pinpointing when and how new memories are strengthened during rest and whether they can detect the spontaneous ‘reactivation’ of new memories in the brain.

Michael Craig & Michaela Dewar
Rest-related consolidation protects the fine detail of new memories
Scientific Reports volume 8, Article number: 6857 (2018) doi:10.1038/s41598-018-25313-y

Top Image: Heriot-Watt University