We can learn as we sleep, new research suggests.A study found that the body is able to take in new information while it sleeps and unconsciously modify the waking behaviour.Sleep learning experiments are notoriously difficult to conduct, not least because the researchers need to be sure that the subjects are actually asleep throughout.

Now scientists from the Weizmann Institute of Science say they have shown sleep learning is possible. Prod Noam Sobel and his team exposed sleeping subjects to a tone followed by a smell, neither of which woke them up.

The odour was either pleasant or unpleasant – eliciting a deep or a shallow breath – and each was associated with a particular tone.
The next day, the now awake subjects again heard the tones alone – with no accompanying odour.

Although they had no conscious recollection of listening to them during the night, when exposed to tones that had been paired with pleasant odours, they sniffed deeply, while the second tones – those associated with bad smells – provoked short, shallow sniffs.

Researcher Anat Arzi said: ‘Now that we know that some kind of sleep learning is possible, we want to find where the limits lie.’

– Daily Mail, London