Researchers from the University of Rochester Medical Center have published a study in the journal Science that finally tells us why it is important that we sleep. This study conducted on rats gives us a peek into how the brain becomes an essential plumbing system when we get a good night’s sleep.

Why Get A Good Night’s Sleep?

Researchers from Rochester conducted a study on rats using new imaging technology to find out what happens in our brains during a good night’s sleep. They have found that our brain becomes a plumbing system that clears out wastes after it is done processing information.

The waste that is cleared out of our brains when we sleep are toxic proteins called beta Amyloids. They accumulate in the fluid in our brain while we are awake and are cleared out while we sleep. During a good night’s sleep brain cells can shrink up to 60% which allows for more room for the clearing of waste.

There are two types of fluids in our brain- Cerebrospinal fluid (CSF) and Interstitial Fluid (ISF). Each night our brain cells shrink and we begin the process of circulation of CSF. This circulation of CSF causes an exchange between CSF and ISF. The ISF is where the toxic proteins are located.

In general, our body uses what we call the lymphatic system to bring waste to the liver and clear it out of our system. However, the brain does not necessarily have a conventional lymphatic system. Researchers have named the plumbing system of the brain the glymphatic system. This name comes from glial cells (brain cells) and lymphatic system. During a good night’s sleep the ISF is circulated to the peripheral tissue and out through the glymphatic system and heads to the liver.

How Does CSF Circulation Help?

Dr. Maiken Nedergaard, one of the researchers on this project, says,  “Nerve cells are very sensitive cells,” and  “Similar to fish in a dirty tank, they will get sick and die if the brain is not cleared.” CSF Circulation stimulates the removal of the toxic proteins in our brain. If we do not get a good night’s sleep every night, our brain gets “dirty.” These proteins could also be linked to Alzheimer’s Disease.

This research was conducted on mice; however, other research shows that it can be done on humans as well. More research is still needed to find out exactly what goes on and to find out how to improve sleep medications for disorders such as insomnia.