A group of researchers, led by Philippe Peigneux, who is a professor at the Faculty of Psychological Science and Education from the Université Libre de Bruxelles Neuroscience Institute, suggest that the learning capabilities of humans are limited during slow wave sleep. Scientists used magnetoencephalography (MEG), which showed that our brains do perceive sounds when we are sleeping, but we cannot organize these sounds in a sequence.
Hypnopedia- which is the ability to learn while sleeping became a popular concept in the 60s when it was mentioned by Aldous Huxley in his dystopia novel Brave New World- in which people are conditioned about their future tasks during sleep. The concept of hypnopedia was avoided by scientists for a long time because of the lack of reliable scientific evidence supporting it.
A few recent studies have shown it is possible for animals and humans to acquire elementary associations like the stimulus-reflex response during sleep, but it is still not clear if one can also attain more sophisticated forms of learning while they sleep.
The study was published recently in the journal Scientific Reports by researchers from ULB’s Neuroscience Institute and reports that although our brains continues to perceive sound while sleeping, just like they do when they are awake, but they lose the ability to group these sounds according to their original organization in a sequence, this can only be achieved when a person is awake.
Juliane Farthouat, who is a Research Fellow of the FNRS under the direction of Philippe Peigneux, used magnetoencephalography (MEG) to analyse and record the cerebral activity which copies the statistical learning of series of sounds during slow wave sleep- which is a part of the sleep cycle during which brain activity is highly synchronized, and as well as during wakefulness.
While sleeping, participants were exposed to rapid flows of pure sounds. They were either randomly organised or were structured in a way that the auditory stream produced by it could be grouped statistically in sets of 3 elements.
According to the research team, while the participants were sleeping, their brain’s MEG responses showed preserved detection of isolated sounds, but there was no response that indicated statistical clustering, and when participants were awake, the MEG responses showed that participants could group sounds into sets of 3 elements.