A new study about a different kind of audio approach during sleep gives insight into how the sleeping brain works, and may eventually come in handy to people studying a language, cramming for a test or memorizing lines in a play.
Scientists at Northwestern University reported that playing specific sounds while people slept helped them remember more of what they had learned before they fell sleep, to the point where memories of individual facts were enhanced.
Researchers taught people to move 50 pictures to their correct locations on a computer screen. Each picture was accompanied by a related sound, like a meow for a cat and whirring for a helicopter.
Then, 12 subjects took a nap, during which 25 of the sounds were played along with white noise. When they awoke, none realized that the sounds had been played or could guess which ones had been used. Yet almost all remembered more precisely the computer locations of the pictures associated with the 25 sounds that had been played while they slept, doing less well placing the other 25 pictures.
The study adds a dimension to a theory that sleep allows the brain to process and consolidate memories.