'Why do we sleep?'. It's a question that has baffled philosophers and scientists for millennia. Only now are we gathering more pieces to get a better picture of this elusive biological puzzle. Everything from worms to mice need their 40 winks. We do know that Sleep deprivation reduces learning, impairs performance in cognitive tests, prolongs reaction time. In the worst case lack of sleep can be fatal if prolonged (or enforced) long enough
An excellent study from the University of Rochester has shown that only in sleep can cebrospinal fluid (CSF) flush brain waste products away from the brain to the liver where they can be elimated from the body.
The rest of the body already has a similar system in the lymphatic network, but this does not extend to the brain. It was not until this study the brain's own plumbing system was identified and that it works best when you are ASLEEP. That explains why whenever we do not get enough sleep for a few nights on a row, we feel groggy, can't concentrate and our ability to rationalise with others goes downhill, often resulting in a bad temper!
The removal of waste from the brain is essential where the unchecked accumulation proteins such as amyloid-beta can lead to Alzheimer’s disease. In fact, almost every neurodegenerative disease is associated with the accumulation of cellular waste products. So this has huge implications that is very much in your control The researchers observed that the glymphatic system was almost 10-fold more active during sleep and that the sleeping brain removed significantly more amyloid-beta.
Sleep literally gives your brain time to 'take out the trash'
An amazing discovery was that cells in the brain “shrink” by 60 percent during sleep. This contraction creates more space between the cells and allows CSF to wash more freely through the brain tissue. In contrast, when awake the brain’s cells are closer together, restricting the flow of CSF.
The researchers observed that a hormone called noradrenaline, the neurotransmitter that makes us more alert' is less active in sleep. Of course this is still a mice study and while there is major differences between mice and men, sleep is a key for our success and demise.
There are more and more reasons that sleep gives you better clarity. For more tips on how you can get better sleep habits read here
Reference Sleep drives metabolite clearance from the adult brain. http://www.ncbi.nlm.nih.gov/pubmed/24136970