Learning can happen while you're sleeping, according to a study performed by the Weizmann Institute.
Prior attempts at research on this subject had been complicated by the fact that while sleep has been shown to be important for memory consolidation and for learning, it remained to be seen as to just how this sleep-enhanced learning takes place.
Prof. Noam Sobel and research student Anat Arzi, along with Sobel's group in the Institute's Neurobiology Department, collaborated with researchers from Loewenstein Hospital and the Academic College of Tel Aviv -- Jaffa. An Aug. 26, 2012 article on Sciencedaily.com reported on the Weizmann study.
Participants' sleep was under constant supervision in a special lab. A tone was played, an odor was released. Another tone was sounded, then another odor was released.
If the first odor was pleasant, the second was unpleasant, or vice versa. As one might expect, the participants inhaled more deeply of the pleasant odors, and breathed in a more shallow manner for the less pleasant smells.
Sometimes the participants just heard tones, without odors. The participants had reactions to the tones in their sleep that were the same as their reactions to the tones and odors.
The different reactions were accompanied by different modes of breathing, deep for pleasant smells, shallow for unpleasant odors. Deep breathing also occurred when the tones that had become associated with pleasant smells were heard without any odor.
After the participants were awake the next day, tones were heard, without any odors. None of the participants had any recollection of the experience through the night, yet their breathing corresponded with the learned behavior of the night before.
Conditioning of this type involves areas of the brain like the hippocampus which plays a role in formation of memory.
Does the phase of sleep play a role as well? The researchers wanted to find out.
In another experiment by these same researchers, reported in an Aug. 26, 2013 article on Sciencedaily.com, it was found that learning was more thorough during REM sleep.