From Nature:
It’s often said that optimistic people look at the world through rose-tinted spectacles. Now it seems that rose-tinted smells can have benefits too. Taking a whiff of rose scent while learning a task and then being exposed to the same smell during sleep helps memories to set, researchers have found. The discovery could see students frantically spraying themselves with perfume before exams — although the effect is tricky to replicate at home.
Jan Born of the University of Lübeck and his colleagues exposed people to the smell of roses one evening while they learned the locations of various picture cards laid in a square. Half of them were then given the same odour to smell as they slept, while the other half had an odour-free night. When they were tested the next day, those who’d had a rosy sleep remembered 97% of the locations — without the roses this figure was 86%.
The team’s findings, published in Science, supports theories about how memories are solidified in the brain during sleep.
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