Sleep Strengthens Your Memory

Sleep not only protects memories from outside interferences, but also helps strengthen them, according to research that will be presented at the American Academy of Neurology’s 59th Annual Meeting in Boston, April 28 May 5, 2007.

The study looked at memory recall with and without interference (competing information). Forty-eight people between the ages of 18 and 30 took part in the study. All had normal, healthy sleep routines and were not taking any medications.

Participants were divided evenly into four groups a wake group without interference, a wake group with interference, a sleep group without interference and a sleep group with interference. All groups were taught the same 20 pairs of words in the initial training session.

The wake groups were taught the word pairings at 9 a.m. and then tested on them at 9 p.m. after 12 hours awake. The sleep groups were taught the word pairs at 9 p.m. and tested on them at 9 a.m. after a night of sleep.

Just prior to testing, the interference groups were given a second list of word pairs to remember.

The first word in each pair was the same on both lists, but the second word was different, testing the brain’s ability to handle competing information, known as interference. The interference groups were then tested on both lists.