Sleep handles many things, and previous research indicated it helped clean the brain, but that may not be the case.

Sleep is something that all animal species do, which shows that it is quite important. One study seemed to show that sleep is very important for keeping a metabolic balance in the brain. Researchers used real-time tests to show that natural sleep or anesthesia is linked to a 60% rise in the internal spaces in the brain. They believed this led to a striking increase in the exchange of cerebrospinal fluid with other bodily fluids.

In turn, the research hypothesized that this sped up the removal of ß-amyloid while you sleep. This particular material has been associated with the neurodegenerative disorder of Alzheimer’s and may be involved in other neurologic dysfunctions as well. So, they assumed a healing effect of sleep might come from better removal of possibly neurotoxic waste products that build up in the brain and spinal cord.

As noted, research over the past two decades indicates that sleep serves more than a restorative or memory-retaining function and clears the brain of metabolic debris that forms during the day. But now that research is being called into question, a mystery we thought was solved may still be out there waiting for resolution.

Remember, not all research with non-human subjects can be extrapolated to humans. But much of the research to date has been with rodents or lower forms of animal life. Neuroimaging devices, however, will make future research more relevant since they will use humans in forthcoming experiments.

What Are the Benefits of Sleep?

Unquestionably, sleep is a vital necessity, and repeatedly, researchers have shown that either a lack of sleep or too much sleep can be deleterious to our physical and mental health. The science is in, and we know what to do, but do we do it? Or do we try to say that we can exist on a little sleep?

Some research has indicated that lack of sleep or no sleep can lead to psychosis (as we saw in the Peter Tripp experiment), mental disorders, and possibly death. There is a sleep disorder that is associated with death. It's called Fatal Familial Insomnia.

We know that memory consolidation takes place as we sleep, possibly because there is a decrease in distraction, and the cells can do what they do to form memories. One thing that students have been told is to study immediately before they go to sleep to benefit from the enhanced memory processing that occurs during sleep.

Some people can function with less sleep but they are in the extreme minority. Most of us require anywhere from 7 to 9 hours of sleep, and teens and babies require even more. Sleep can also be diagnostic when individuals indicate they need to sleep more during the day and night, indicating impending dementia. In fact, longer sleep length may be a sign of early neurodegeneration, and as a result, it can identify people who are more likely to develop dementia within 10 years.

New Findings on Brain Clearing

Scientists believed that a major step had been taken to explain the brain-clearing processes that occur during sleep. The comfort they may have felt coming to this conclusion is now being questioned. So sleep isn't the brain's housekeeper, as we had been previously led to believe?

It is still not clear how chemicals and toxins leave the brain. There are disagreements about the physical pathways and how they eliminate material. It had been said that during non-rapid eye movement (NREM) sleep, solutes were actively cleared from the brain by the mass flow of fluid. This is now being called into question, even though we know a new brain-clearing pathway, the glymphatic system, has been discovered within the past few years.

New experiments show that brain clearance is lower during sleep and anesthesia, which contradicts previous studies. The authors of these latest experiments indicate that methodological errors were made in using dye to enter and leave portions of the brain during sleep. These errors, they believe, are responsible for the conclusions that were drawn and which are now being called into question. No matter what the process is, these researchers note previous conclusions that the idea that sleep’s main job is to get rid of waste from the brain is debatable.

It is possible that the brain actively clears out waste materials as we sleep or even during the day. Until we have firm statistical evidence of the total organization and the many mechanisms of the brain, we will continue to search. In the meantime, this doesn't mean that you should skimp on sleep because it remains a vital part of our lives, and without it, there will be a price to pay.