BOB HIRSHON (host):
Selective storage in sleep…I’m Bob Hirshon and this is Science Update.
It’s long been known that sleep transfers memories to long-term storage. Now, German researchers have shown that the brain chooses which memories to store. University of Lübeck neuro-endocrinologist Jan Born and his colleagues taught volunteers either a list of paired words or a finger-tapping exercise. Afterwards, half were told there would be a test in two days. But actually, all of them were tested.
JAN BORN (Univ. of Lübeck & Univ. of Tübingen, Germany):
Only when they were informed about the later recall, there was robust, very substantial benefit for these memories during sleep.
In contrast, the group that hadn’t expected a test improved only a little. Born suspects that the brain tags important experiences throughout the day, and preferentially stores the tagged memories while we sleep. I’m Bob Hirshon, for AAAS, the science society.