In a study, researchers from Concordia University in Canada and the University of Liege in Belgium have found that Brainwaves produced during sleep helps us to store new information in our memory which helps boost learning.
The study, published in the journal NeuroImage, shows how learned information turns into reliable memories during sleep.
Brainwaves — specifically, ones called sleep spindles, are fast bursts of electrical activity produced by neurons mainly during Stage 2 sleep, prior to deep sleep.
Using medical imaging machines, researchers were able to assess brain activity related to these waves.
Thanh Dang-Vu, Associate Professor at Concordia University said, it's hypothesised that sleep spindles play an important role in transferring information from the hippocampus to the neocortex. This has the effect of increasing the strength of memories.
To get the images they needed, the team used both electroencephalography (EEG) and functional magnetic resonance imaging (fMRI).
They applied these tools to a group of student volunteers during and after a lab-based face-sequencing task. The students were shown a series of faces and asked to identify the order in which they were shown.
The researchers scanned them while they were learning the faces, while they were asleep and again when they woke up and had to recall the sequences.
They then came back every day for a week and repeated the task without being scanned. After a week had elapsed, they had memorised the task, and were once again scanned during sleep and asked to recall the sequences.
The researchers found that during spindles of the learning night, the regions of the brain that were instrumental in processing faces were reactivated.
They also observed that the regions in the brain involved in memory — especially the hippocampus — were more active during spindles in the subjects who remembered the task better after sleep.
Researchers said that this reactivation during sleep spindles of the regions involved in learning and memory falls in line with the theory that during sleep, memories are strengthening by transferring information from the hippocampus to the regions of the cortex that are important for the consolidation of that specific type of information.
