Researchers have discovered how we store dreams – and why some people can never remember them the morning after.
A French team say they have identified two types of dreamer – and only one can remember them.
They discovered a region in the brain responsible for remembering dreams, allowing them to be encoded in our memory while we sleep.
The team were puzzled by the fact some people recall a dream every morning, whereas others rarely recall one.
The researchers found the temporo-parietal junction, an information-processing hub in the brain, is more active in high dream recallers.
Increased activity in this brain region might facilitate the encoding of dreams in memory, they believe.
In a study published in the journal Neuropsychopharmacology, the team found ‘high dream recallers’ have twice as many time of wakefulness during sleep as ‘low dream recallers’ and their brains are more reactive to auditory stimuli during sleep and wakefulness.
This increased brain reactivity may promote awakenings during the night, and may thus facilitate memorisation of dreams during brief periods of wakefulness.
‘This may explain why high dream recallers are more reactive to environmental stimuli, awaken more during sleep, and thus better encode dreams in memory than low dream recallers. Indeed the sleeping brain is not capable of memorising new information; it needs to awaken to be able to do that,’ said Perrine Ruby, who led the study.