Professors V. Vyazovskiy and Kenneth D. Harris say nothing is worth more than sleeping through the day

Want to sleep into the day? Vladyslav V. Vyazovskiy and Kenneth D. Harris, say nothing is more worth it; you may actually be helping your body. In an interview about their paper in NATURE on sleep and the kind of rest it gives, they propose answers to questions like why we lie inert for so many hours, why all aspects of our brain shut down instead of taking turns to do so and so on.

When we are asleep, low frequency co-ordinated brain wave oscillations wash over the whole brain unlike in the day when activity looks very spiky.Scientists think perhaps that is when memories are made and consolidated. Or maybe, it is when the brain takes a breather and repairs itself. Vyazovskiy and Harris propose that sleep is a prophylactic, a mechanism that stops cells from being damaged beyond repair.

“In a way it is a kind of intuitive understanding that people hold…sleep is required for rest and recuperation. The question always was what kind of rest and why do you need to lose consciousness to get this kind of rest?” asks Vyazovskiy.

“Whenever you have any complex machine and it needs to be repaired, presumably you cannot do it while it is still running. It needs to be shut down. This idea has been around for a while. The question that still has to be answered is why this oscillating state…that is the brain cells come on and off together. When they shut down, they all shut down together,” says Harris.

“We think that neurons simply cannot sustain continuous activity, for if they did as in some pathological problems like epilepsy, this would lead to irreversible damage…so as Kenneth was giving the example of a complex machinery, you do not wait till the machine breaks down. You fix maintenance on weekly, monthly basis and fix small things before it breaks down. This is what we think sleep is doing,” says Vyazovskiy.

While it is clear that the cells need to stop working for some time, Harris says they do so together, “…simply because they are all connected to each other. When some of them fire, all the rest of them fire. You cannot simply have one of them trying to rest while the others are partying. That is why they all have to switch off and on together. This is what causes the oscillations.”

The hypothesis is that the cellular stress and the need for repair cause the oscillations to happen. The way to test that is to make cells stressed so that they need to repair themselves and the prediction is that the application of that kind of stress will increase the need for sleep. So inducing cellular stress in one part of the brain should cause the strongest oscillations in that very same part.

“What happens if you are chronically sleep deprived? Will it hinder cellular maintenance? The evidence is not conclusive that sleep deprivation leads causally to neuro-degeneration, however there are a lot of things that seem to associate the two,” says Harris.

“If you look at the entire human population you see a lot of our ability in the amount of sleep. This provides interesting and further clues and tools to answer the question of what cellular damage can happen if we are chronically sleep deprived. There are short sleepers…they sleep only four to five hours a day and they can live like that all their life and they do not have any neuro degeneration.. There are others who sleep ten hours a day. Also when you are younger you sleep longer. When you are older you sleep much more superficial. Our brain has the capacity to get the necessary rest in a very efficient way in a very short time. But I hope our article will help us understand at what level of brain organization the function of sleep can be found…to understand that is vital for it can provide clues to neurological disorders,” says Vyazovskiy.

One thing is clear and un-debatable: sleep is vital…pull the blanket closer!


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