Replay Of Information In High-Quality Sleep Benefits Memory, Study Finds

Health News – A study finds that memory storage improves when information is spontaneously replayed during ample and undisturbed slow-wave sleep. The study further looks to investigate more complex issues surrounding memory accuracy and disrupted sleep.

New research by Northwestern University links improved memory (especially in face-name learning) with spontaneous replay of information during high-quality sleep.

The study involved 24 participants, aged between 18 to 31, who completed a face-name learning task in two consecutive classes, with 40 face-name pairs per class. Each class was associated with a distinct music track, namely, Latin-American music and traditional Japanese music. What followed was recall training for each class separately, one after the other. The participants were shown face visualizations and prompted to recall corresponding names. In the next phase, participants were asked to visualize each person when the corresponding name was spoken.

After this experimentation, the participants were asked to take a nap. Participants slept for a mean of 59 min, with Targeted Memory Reactivation (TMR) beginning at a mean of 7.3 min after sleeping. The researchers carefully recorded electroencephalogram (EEG), electrooculogram (EOG), and electromyogram (EMG) signals during the nap using a BioSemi Active2 system with 32 scalp channels and 4 electrodes on the face. As the participants reached the N3 “deep sleep” state characterized by EEG slow waves, some of the names associated with one or both classes were softly played on a speaker with either Latin-American or traditional Japanese music. After the participants woke, the same recognition and recall tests were implemented. The results of the surveys from pre-sleep and post-sleep phases were then examined.

The findings, published in npj Science of Learning, revealed that people’s recognition and recalling of names improved significantly when memories of recently learned face-name associations were reactivated while they were in uninterrupted deep sleep. Reinforcing the already established value of high-quality sleep, the study strives to delve deeper into the larger questions surrounding memory storage and accuracy, disruptions in sleep, high-quality sleep, and sleep disorders.

“This new line of research will let us address many interesting questions—like whether sleep disruption is always harmful or whether it could be used to weaken unwanted memories,” said Ken Paller, the lead author and professor of psychology and director of the Cognitive Neuroscience Program at Weinberg College of Arts and Sciences at Northwestern University.

To Know More You May Relate To

Whitmore, Nathan & Bassard, Adrianna & Paller, Ken. (2021). Targeted Memory Reactivation of Face-Name Learning Depends on Ample and Undisturbed Slow-Wave Sleep. 10.1101/2021.02.16.431530.