According to a new study carried out by researchers, the effects of sleep deprivation go way beyond just a feeling of tiredness. Their observations determined that, in cases of sleep and severe sleep deprivation, the brain can seemingly turn against itself, in a counterintuitive process.
Study results were released in a paper in the Journal of Neuroscience.
Past research has shown that, during sleep hours, the brain changes states and starts clearing away and getting rid of the leftover toxic bioproducts of the day’s neural activity. This same process was noted, to quite a bit of surprise, to happen in sleep deprived brains as well. Only, here the process comes with a big difference, as it was noted to go on overdrive when compared to the usual process.
Also, a persistent state of sleep deprivation may have significant effects because of this. As the brain clears away a significant amount of synaptic connections and neurons, even sleeping might not be able to help recover these lost elements.
Sleep Deprivation, High Impact on the Brain?
The study was carried out by Marche Polytechnic University in Italy scientists led by Michele Bellesi. They studied the mammalian response to sleep habits in the brains of both well-rested and tired mice.
The brain uses two different sorts of glial cells (also known as the glue of the nervous system) to ‘refresh’ itself. Microglial cells help dispose of worn and old cells in a process called phagocytosis. Astrocytes get rid of unnecessary neuron connections or synapses.
These two processes occur naturally as we sleep. But they seemingly also take place even if the brain doesn’t rest.
“We show for the first time that portions of synapses are literally eaten by astrocytes because of sleep loss,” stated Bellesi.
The team of researchers reached this conclusion after studying the brains of sleep and severe sleep-deprived mice.
They noted that astrocytes in a well-rested brain were present in 5.7 percent of synapses. But in the sleep deprived mice groups, they were present in up to 8.4 or even 13.5 percent of the synapses. These also displayed an increased clearing away activity. They discarded the most heavily used and oldest synapses, which was not necessarily bad, apparently.
But such brains also showed an increased microglial activity, which is certainly not good. This has been linked to neurological problems such as Alzheimer’s.
The team still has many questions to answer. For example, if this same process occurs in humans as well. Or if getting enough sleep can counteract the increased cleaning.
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