by John W. Mitchell
, Senior Correspondent | August 13, 2015
It turns out the most popular sleep position for people and animals – lateral, or sleeping on your side – may affect the odds for neurological disorders.
A research team used dynamic contrast MR studies on rodents to reach this conclusion.
“The brain is one of the most metabolically active organs, so it produces a lot of metabolic waste that needs to be recycled or gotten rid of,” Dr. Helene Benveniste, principle investigator told HCB News. She is professor of anesthesiology and radiology and vice chair for research, department of anesthesiology, Stony Brook Medicine. “If these substances are allowed to accumulate they become misfolded and aggregate.”
That aggregation may contribute to the likelihood of developing neurological disorders, she explained.
The study was recently published in the Journal of Neuroscience
and builds on the discovery of the glymphathic pathway which was previously uncovered by another research team in 2012. This system acts as a waste clearance pathway in the central nervous system of rodents and is most active during sleep. The study strongly suggests that humans have a similar brain network to eliminate brain waste, although this has not yet been proven.
“Once Dr. Maiken Nedergaard’s team at Rochester discovered the glymphathic system in rodents, we naturally asked the question which sleep position makes the system most efficient,” explained Dr. Benveniste.
The study was conducted over several years by examining anesthetized rodents sleeping in the lateral (side), supine (back) and prone (face down) positions. The data revealed that side position did the best job of flushing brain waste, followed by the back and face down positions.
“Side sleeping seems to be the preferred position for humans and many animals. Of course we change positions many times a night,” Dr. Benveniste explained. “I was surprised to see [videos showing] that even large animals like elephants side-sleep.”
Researchers know that human dementia is often marked by an onset of sleep difficulty.
“The small rodent brain can teach us a lot about the waste removal pathways from the brain and spinal cord,” Dr. Benveniste added. “But we need to study it in the brain of humans to begin to understand it.”