Sleep Learning – How Subliminal Sounds Boost Memory

Image: CollegeDegrees360

Sleeping with your eyes open is creepy, but for some reason everyone is just psyched that our ears stay open and can aid our learning even while we’re deep in slumberland.

Here are some things our brains actually become better at through sleep and subliminal sounds (something to tell Teacher next time he/she catches you asleep in class).

Foreign words  

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Always wanted to learn Spanish, French or Mandarin? A study found that people who were learning foreign words and exposed to them again while sleeping performed better once they woke up.

The German-speaking participants of the study started learning Dutch, and then took a nap in two groups. While they were sleeping, one group was played some of the Dutch words, while the other was not. The result: the group that had heard them in their sleep was better able to identify and translate the Dutch words, recalling about 10% more. Wauw!

Musical skills 

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In an upgrade from Mozart-for-babies, a study found that sleeping to the sound of a tune you’re learning can help you perform it better later. After teaching participants melodies using a format similar to Guitar Hero, study participants were allowed to hit the hay. As they slept, one group was played the sound of the tune they learned. After they woke up, those who had been played the music actually performed it far better than those who did not. Sleep + music = rock star. Who knew?

Locations

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And it doesn’t stop with memories of sounds. Even the locations of things can be better recalled – if we first associate them with sounds and then hear the sounds while we sleep.

In this study, 12 participants were taught specific locations to place 50 images on a computer screen (they practiced arranging them until they got pretty good at it). Each picture also had its own special sound effect (a shattering wine glass sounded like breaking glass, and a photo of dynamite sounded like a muffled explosion).

Later while they napped, researchers played 25 of the 50 sound effects back at them, though nobody woke up or remembered hearing it. When they got up and tried to arrange the 50 items again, they could better recall the locations of the 25 objects whose sounds they heard in their sleep, compared to the 25 they had not. Now if we only know the sound a left sock or missing house key makes…

Mastering a skill while snoozing like a log is still a pipe dream, but the good news is that sleep – far from being a vegetative state –  is when our brains consolidate knowledge, turning new short-term memories (like Dutch words, guitar tunes, or the whereabouts of dynamite) into long term ones.

Thus the next time you’re stuck between revising one last time and going to bed, remember: with enough rest (and maybe a family member reciting your school work while you sleep) you can actually retain more information, and maximise your waking performance.

By Vincent Tan