One of the reasons we need sleep is that it helps us to store up memories. But the brain is selective about which memories it keeps, says a new study in the Journal of Neuroscience.
Researchers at the University of Tübingen in Germany found that sleep only enhances our memory of facts we expect to need in the future.
They asked 191 adults to perform different memory tasks, such as memorizing word pairs. Half of the subjects were told to expect a test nine hours later, while the others were told they would be doing something else. Before the test, some subjects were allowed to sleep. Participants who had anticipated a test recalled 12 percent more word pairs than those who slept with no expectation of a test, say researchers.
The findings are convincing, says Penny Lewis of the University of Manchester, UK, in New Scientist. They suggest that “if you tell someone something is important, it gets enhanced more.”
So if you want to make sure that your husband remembers your anniversary, stress how important it is—and then put him to bed.