"We show for the first time that portions of synapses are literally eaten by astrocytes because of sleep loss," said lead researcher and neuroscientist Michelle Bellesi, talking to New Scientist.
This news isn't initially scary, as this is a normal, healthy function. Much the same as cells replace themselves in your body, neurons in our brains are constantly refreshing and replacing themselves as well. This process, called phagocytosis, occurs during sleep as an essential process of keeping our brains healthy and removing the wear from the day.
However through the study of mice, the scientist identified this process occurring at heightened levels in those that were sleep deprived. When this happens, the brain goes overboard and clears out up to 13 per cent more synapses than normal, and more than need clearing out.
According to the research, the neurons that are cleared due to sleep deprivation are the older, more highly used synapses.
"We find that astrocytic phagocytosis, mainly of presynaptic elements in large synapses, occurs after both acute and chronic sleep loss, but not after spontaneous wake, suggesting that it may promote the housekeeping and recycling of worn components of heavily used, strong synapses," the researchers report.
"By contrast, only chronic sleep loss activates microglia cells and promotes their phagocytic activity ... suggesting that extended sleep disruption may prime microglia and perhaps predispose the brain to other forms of insult."
While this may sound complicated, unchecked microglia priming has been linked to brain disease, such as Alzheimer’s.
How do you combat this aggressive behaviour in your brain? Hit the hay regularly, for at least 7-8 hours every night, and don’t underestimate the power of a good nap.
