It turns out your brain is up and down more often than a bloke with a troublesome prostate.
Most of us love a good kip, and would be surprised upon waking from slumber to hear that weâve actually woken up 100 times already since we went to sleep.
Researchers from the University of Copenhagen have found that the stress transmitter noradrenaline wakes your brain up many times during the night, without your noticing, and with important benefits for memory.
In a study published last week in Nature Neuroscience, top neuroscientist and study lead Professor Maiken Nedergaard and her team laid out in very wide-awake fashion how noradrenaline levels pulse through the brain at night, up and down and so on.
The levels change constantly in a wave-like fashion: peak noradrenaline is when youâre briefly awake, deep in the trough of the wave is when youâre well in the land of nod.
The team established this with the help of some mice whose brains were hooked up to micro fibre-optic cables, allowing the researchers to measure both noradrenaline levels and electrical activity while the rodents got some shut-eye.
To be fair this kind of âwaking upâ isnât the same experience as you get when your neighbour discovers their best time to practise the drums is 3am.
Waking up in this context meant waking up âneurologicallyâ, with the brain as electrically active as it is when properly awake â which is why the mice woke up apparently feeling nicely rested.
Memory was also a key focus of the study and it turns out the rodents with the deepest noradrenaline wave troughs were found to have the best memories.
Since the study involved mice, the usual caveat applies, but the team seem to think thereâs a good chance the findings would be replicated in us humans.
If you have a scary dream, send your journal to penny@medicalrepublic.com.au.