There was a time when studying in school involved a lot of memorizing. Times may have changed – new educational methods emerged – but “old school” folks remember well the most effective technique of learning a poem by heart: recite it several time just before sleep. The next morning, it would be imprinted in your memory as if it were carved in stone.
The exact way in which the brain induces learning processes can be exemplified by how humans learn to play a musical instrument – the piano, for instance. Studies have shown that systematic practice encourages the brain to build new neuronal links that facilitate coordination between the musician's mental intent and fingers. It takes about three months for these links to grow and develop into a full-fledged form – and that's when the persevering student's ability will start to improve notably.
But that is a long term change that cannot explain the improvements we experience after a good night's sleep. Recent research not only confirms that sleep helps in the process of acquiring new knowledge, but also shows how. According to the study, the brain reorganizes information accumulated during the day in a such a way as to allow better performance the following day. The scientific term for this process is “nighttime consolidation.”
With the goal of reaching a deeper understanding of nighttime consolidation, psychologists and biologists started observing birds, focusing on juveniles that study songs from adult tutors. The findings allowed them to arrive at two conclusions: first, that young chicks of the zebra finch species practice new songs during the day, and, the next day, after a good night's sleep, sing better.
Second, that those parts of the brain that are active during actual singing, also participate in consolidating yesterday's learned songs during the night. Thus, the next morning, even before the bird has had the chance to practice, its brain has already done all the preparation and optimization: its “own” practicing. At this stage the young finches continue to practice in order to improve their singing.
Some scientists say that these discoveries may attest to the power of dreams – which even the little finches may be having.