The major scientific conclusion is that we do not learn from what we hear while asleep. Sleep is important in the process of learning, however.
If one learns a list of nonsense words, memory of them eight or twenty-four hours later is better if we have slept; memory eight hours later without sleep is not as efficient as twenty- four hours later with intervening sleep. This suggests memory traces are strengthened during sleep.
That we do learn, in the sense of creating new information or perception, while we sleep is generally accepted. Albert Einstein suggested that the creative scientists are those who have access to their dreams. He meant that in order to be innovative we must be able periodically to leave behind the practical everyday path of commonsense and rational thought.
The rational tends to move in areas of thought connected with what is already known.
To create something new, to find a new direction, we may need to be capable of retrieving apparently irrational ideas, sift them and reconstruct them in practical ways.
Dreams have this ability to fantasise, to look at and experience the irrational, to take an idea and move it completely out of its old setting or viewpoint. Because our mind can do this in sleep, we can touch not only our creativity, but also our ability to problem solve. As a personal test of this, try the following experiment. At the end of this explanation a problem will be set. It is one that requires no special training or information to solve.
The solution is simple and will be seen as conect when reached. But do not even begin to think about the problem until you go to bed! It would discount the experiment if you did. On going to bed, think about the problem for no more than 15 minutes.
If you solve the problem note how long it took.
If not, stop thinking about it and go to sleep, making the resolve to remember any dreams. It is likely that you will dream the answer.
If not, on waking spend a funher 15 minutes trying to reach the answer.
The letters 0,T,T,F,F,-,-, form the beginning of an intelligible series. Add two more letters which make it obvious that an infinite number of letters could be added. ... A Guide to Dreams and Sleep Experiences