Having a nap is a great way to consolidate your memory for what
you’ve just learned. Now it appears researchers have found a way
to boost this beneficial effect. A control condition confirmed
the benefits of sleep: 13 participants remembered 37.42 words in
a memory task before sleep, compared with 39.5 on waking. On
another occasion with a different set of words, Jan Born and
colleagues applied an oscillating electrical current through the
participants’ skulls just as they were entering a period of
slumber known as slow wave sleep. In this case the participants
recalled an average of 36.5 words before sleep, compared with
41.27 words when they were tested on waking – a larger benefit
than in the control condition. "This improvement in retention
following stimulation is striking considering that most subjects
were medical students, who were highly trained in memorising
facts and already performed well in the sham [control]
condition", the researchers said. During slow wave sleep,
populations of neurons oscilla