Philippe Peigneux, one of the leading scientists at the ULB Neuroscience Institute, with the help of other researchers found out that our learning capabilities are limited when hitting the sack – particularly slow wave sleep. Magnetoencephalography results showed that although our brain is able to perceive sounds during sleep, it cannot group those sounds according to their organization in a sequence. This means our mind can perceive simple information, but it is very unlikely we can actually learn something during sleep.

In the 1960s, the ability to learn while sleep, also known as hypnopedia, was very popular.  Hypnopedia was also further popularized by a dystopian novel dystopia Brave New World by Aldous Huxley. In this novel, individuals were conditioned to their future tasks during sleep. However, a few years later, this idea was abandoned due to lack of scientific evidence that support in-sleep capabilities.

New studies have shown that during sleep, acquisitions of elementary associations are possible both in humans and animals. These associations are actually stimulus-reflex responses. However, research has shown that in-sleep learning capabilities are minimal, especially for more sophisticated forms of learning.



On August 6, the journal Scientific Reports has published a sleep study that shows that our brain will continue to perceive sounds the same way as in the state of wakefulness; however, the ability to group these sounds in a sequence completely disappears during sleep, and it’s possible only in a wakeful state.

Researchers Philippe Peigneux, a professor at the Faculty of Psychological Science and Education at Université Libre de Bruxelles, and Juliane Farthouat, a scientist at the National Fund for Scientific Research, used magnetoencephalography to record cerebral activity during sleep while mirroring the statistical learning of series of sounds. MEG recording was conducted during slow wave sleep and wakefulness. Researchers have decided to record slow wave sleep because this is a part of sleep during which brain activity is highly synchronized.

Participants of the study were exposed to different sounds, either randomly organized or structured in such a way that the auditory stream could be grouped into sets of 3 elements. During sleep, MEG results have shown that the brain detected only isolated sounds, and completely ignored statistical clustering or the possibility to organize the sounds into sets of 3 elements. During wakefulness, MEG results show that all participants responded to the grouping of sounds into sets of 3 elements. From the results, we can conclude that our in-sleep learning capabilities are limited to simple and elementary associations.