By: Jenna Savage
If you’re a student, you know that it’s not always easy to find the time to study everything you need to know for your classes. Of course, if you could learn in your sleep, that would solve potential time-management problems. However, sleep-learning, an idea that has been propagated by movies and cartoons, has up until now seemed impossible. Research studies have shown that falling asleep while listening to the sounds of language instruction or the drone of someone reading a textbook isn’t going to infuse the knowledge within your brain. Sleep-learning has therefore seemed like a fantasy, rather than a real possibility.
Recently, however, new research has emerged to prove that learning can take place during sleep — just not necessarily in the ways people previously imagined. According to a PsychCentral article, a study, which will be published in the journal Nature Neuroscience, explored sleep-learning in an unusual, but effective, way. Conducted by Dr. Noam Sobel, who studies the sense of smell, and Anat Arzi, a research student, the study subjected participants to different odors while they were asleep. But before each odor was released into the participants’ rooms, a tone sounded — one that remained consistent with the smell to which it was associated.
Using this combination of tone and odor gave the researchers the opportunity to observe the participants’ reactions without waking them up, while also getting some insight into the way they reacted to the tone and odor. It also allowed researchers to see whether or not the participants were processing the odors, as they were able to observe the non-verbal act of sniffing.
Even while they were asleep, the participants reacted to the odors. If the odors were unpleasant, they breathed shallowly. If the odors were pleasant, they breathed in deeply. In addition, once the tone was presented without the odors, the participants still reacted as though smelling the odor that had been associated with the particular tones. This indicated that learning had taken place, despite the participants’ sleeping state.
During the following day, while awake, the participants continued to react to the tones alone — breathing in deeply after the tones that were associated with pleasant odors, and breathing in shallowly after the tones that were associated with unpleasant odors. While sleeping, they had learned the associations — and they were still in effect once the participants were awake.
Further research showed that rapid eye movement (REM) sleep promoted learning better than non-REM sleep, but non-REM sleep offered better waking recall. This may be because REM sleep leaves people more open to influence than non-REM sleep. However, REM sleep may also lead to what is known as “dream amnesia,” the culprit responsible for forgotten dreams.
Now that researchers know that learning while asleep is a possibility, more research will be able to determine what exactly sleep-learning can do for people and what limits there may be.