We’ve all struggled with going without sleep, and heard about the havoc forgoing your seven to nine hours of shuteye will wreak on your life. But why do we need sleep?
According to RT, a group of scientists have discovered that the purpose of sleep changes dramatically after two-and-a-half years of age. Apparently, at this age, we need sleep for “permanent damage-control function” rather than rapid growth.
The #sleeping brains of infants and toddlers are focused on learning + memory support until ~ 2.4 years of age, when brain activity shifts to spend more time on maintenance + repair, according to @ScienceAdvances study by @VanMSavage. Story @colinaoconnor https://t.co/iq3adPV5QI
— Meagan Phelan (@MeaganPhelan) September 18, 2020
Their study, published in the journal Science Advances, used quantitative analysis of things like cerebral metabolic rate, brain size, REM sleep and more, to determine why our need for sleep changes between two and three years of age.
Apparently, all animals – including humans – experience “ongoing background brain damage” as a result of simply being alive. The low-level damage results in debris that can accumulate and eventually cause brain disease. Sleeping helps to clear the debris.
Never has the feeling of ‘clearing away the cobwebs’ in the morning felt so relevant.
Before we reach two-and-a-half years old, scientists found that the primary purpose of shuteye is to “build and strengthen synapses, the connections between the neurons in our brains,” RT reports.
Scientists also found that there is an interesting relationship between brain growth and amounts of REM sleep. For example, newborn babies experience around 50% REM sleep for optimum brain growth. 10-year-olds, on the other hand, only get 25% and adults over 50 get just 15%.
RT reports that while researchers suggest snoozing “when needed to stave off potential problems with brain disorders in later life,” others have argued the study doesn’t take into account factors like day length, diet and climate, which can also have an impact.
Either way, it’s pretty impressive that sleeping isn’t just providing us with energy to take on the day, but is quite literally wiping the slate clean. Perhaps it’s time to do away with the all-nighters once and for all.