Breakthrough In Sleep Research Shows Brain Self-Cleaning Aided By Sleep

self cleaning brain while sleepingIt has been an amazing week in sleep research, which made big headlines all over the mainstream press. Scientists from the University of Rochester announced that sleep is connected to the brain’s self-cleaning and chemical reset mechanisms. There have been ideas about why we sleep before, however this is the first time direct neurophysiological evidence has been provided – even if only in mice.

I will summarize the findings of the research team below. After that my own thoughts on how this links with the current models of why we sleep, dreaming and how it might affect of influence future breakthroughs in sleep science.

It was a separate breakthrough last year which lead to this new discovery. This concerned the way the brain clears stray proteins and unwanted molecules which find their way outside the brain cells. There are pathways between the cells, which the ‘cerebrospinal fluid’ travels through, collecting these stray objects and clearing them away.

The new research showed that while mice are asleep, the pathways through which this fluid travels are expanded. Glial cells, which keep the neurons healthy, shrank to form wider channels, allowing for better circulation of the cerebrospinal fluid. In turn this was transferred to the blood, where the liver could break down the toxins and remove them from the body altogether.

This process does take place during waking hours, only at a far slower rate. Scientists have speculated that the energy intensive nature of this process means that sleep is ideal – the brain and body are far less busy doing other things.

Brain Cleaning And Sleep – Some Implications

First, the build-up of toxins in the brain is closely associated with Alzheimer’s disease. This allows researchers into treatments for that condition a new avenue for their investigations.

There are many questions raised here. First, whether there is a relationship between the accumulation of stray proteins and toxins in the brain and feeling sleepy. If ‘yes’ when what mechanism is controlling the subjective sleepiness?

Once we understand this relationship better, there may be new ideas on both staying awake and even new ways of inducing sleep (for example mimicking the need to give your brain a wash, and thus naturally inducing sleep!).

Brain Toxins And Sleep – Adding My Own Thoughts

As an eternal optimist I can’t help wondering whether drugs which help the brain self-clean might be a key element on creating a future where we do not need to sleep so many hours to be healthy. This is a long way off, we only just got to defining the process in mice – and even that is yet to be replicated by other research teams. Could the massive funding for the terrible condition of Alzheimer’s move research forward on this front quickly? If it works there might be a commercial opportunity for ‘big pharma’, and their research billions.

Another thought is to wonder how brain-cleaning and Sleep-Apnea are related. This breathing condition causes people to wake up many times during the night (even if they are not particularly aware of it). Could the disruption of brain cleaning function explain the lower quality of sleep for sufferers of this condition? If yes, then a milder treatment, maybe something to speed up the washing process in the short-term, combined with standard Apnea treatments, could be really helpful.


There is no doubt this is exciting research. It has put the importance and the mystery of sleep into the public eye for the first time in years.

What it really does highlight for me, is how much in its infancy our knowledge of sleep, and of the mechanisms controlling the brain, really is.

We know that memory and sleep are linked (though only through ‘brain areas’ lighting up – not at the detailed level). We know that physical rest is good for organ and tissue repair, though again not exactly how the two processes are joined.

This really is the first time a mechanism as well as an area have been linked to sleep. I look forward to the study being replicated and built upon – this really could be a breakthrough in both our understanding of sleep, and potential treatment of sleeping disorders.

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