Myths And Truths About Learning During Sleep

Learning during sleep, or hypnopaedia, has been widely touted. There are many advertising messages in which it is ensured that it is enough to leave the lesson “playing” while we sleep and when we wake up we will have acquired a series of knowledge. Is this true? What does science say about it?

The attractiveness of the method is how little effort it takes for the results it promises. Supposedly, you learn without making any effort. And, in theory, you learn well: you end up knowing something new without realizing what time it is, and also without bumps or mistakes. This is seen as a panacea for those who are not very into studying. You fall asleep ignorant and you wake up knowing.

As an advertising theme it is, without a doubt, very attractive. However, in practice things can be very different. Perhaps the merchants have started from a scientific base, but at some point they have taken it much further than where it can actually go. Let’s see what this is all about.

Learning during sleep

First of all, it must be said that learning is a process through which a transformation occurs in the perspective or behavior of a person, based on acquired experiences. Such experiences can be physical or mental in nature. The bottom line, in any case, is that after learning something, the person is no longer as before.

On the other hand, learning is not only what is consciously remembered. Memory is only one part of that process. Learning not only generates memories, but changes in attitude , in the way of doing and seeing reality.

Now, during sleep there are basically two phases: the paradoxical dream and the non-paradoxical one. The first is also called “rapid eye movement,” or REM. Science has discovered that there is a relationship between this phase of sleep and memory consolidation. However, these mechanisms are not yet fully understood.

However, it has been established that the memory that is consolidated during this phase is the long-term one. Also that if the person is deprived of that period of sleep, not only forgetfulness occurs, but also a state of stress. If a person receives external stimuli during this phase, they will not rest properly. Despite this, is learning possible during sleep?

A suggestive experiment

To establish whether learning during sleep is possible, an experiment was carried out at the Weizmann Institute in 2014, which was later published in Nature Neuroscience . The experiment had to do with learning by conditioning. The sleeping volunteers were made to ring a series of bells with different tones. At the same time, a scent was spreading. This was repeated several times, but in the end they removed the olfactory stimulus.

The next day, some members of the same group were consciously subjected to sound stimulation. The result was that almost all of them experienced the scent of the night before, even if it was not present. In a word, they had “learned” to associate both stimuli, while they were asleep.

This leads to the conclusion that it is possible to generate a certain type of learning during sleep, although with very precise limits. The first, that what was generated was a totally mechanical learning, without rationalization. None of those who participated in the experiment remembered what had happened the night before. Likewise, over time they also stopped associating sound and smell. So it was all about very basic and short-lived learning.

Some partial conclusions

What did surprise the scientists at the Weizmann Institute was that learning during sleep, limited as it was, had been acquired in phases other than REM. The brain appears to be more receptive to external stimuli during the REM phase, but the opposite was true in the experiment.

The truth is that what we do not know about the dream is still much more than what we know about it. What is clear is that it is a fundamental process for the human being. When the brain sleeps it does a kind of purification, eliminating data that is useless and consolidating those that are relevant. At the same time, when you don’t sleep well, negative health consequences arise.

So far there is no evidence on learning during sleep, at least on issues that require reasoning. There is also no certainty about the duration and scope of some other learning that occurs during sleep. So, for now at least, we’ll probably keep learning the traditional way.