[Science] Staying up late will really make you stupid!

Staying up late is the most common way of life for scientific researchers, some even reverse day and night, out of experimental study helplessness, some just get used to it, the more mental picture is in the middle of the night

But if things go on like this for a long time, you will really slowly become stupid!

Why do we stay up late and get groggy after getting up early?

The top journal Science published a study from the research group of Professor Laura Lewis, Department of Biomedical Engineering, School of Engineering, Boston University.

And this kind of cleansing can only be done after falling asleep, so that people wake up and have a refreshing brain; when they are not asleep, the cerebrospinal fluid does not have a sufficient opportunity to enter

So research dogs, sleep more and don't stay up late

Why can you brainwash only when you fall asleep

When you fall asleep, the brain goes through several different stages:

After falling asleep, light sleep, deep sleep and deep sleep, we will enter the rapid eye movement (REM) sleep period, which is a state of easy dreaming

Scientists collectively refer to the first four stages as the "non-rapid eye movement period

In fact, studies in 2013 have proved that during sleep in mice, toxins like beta amyloid are eliminated from the brain

The question is, how did it get rid of it? Why can it be cleared only when sleeping?

Scientists conducted an experiment in which 13 humans put on EEG caps and slept in an MRI machine

Then found a strange phenomenon:

The blood oxygen concentration in the brain has obvious major periodic changes

At this time, the cerebrospinal fluid will take the opportunity to rush into the brain, filling up the space left for it:

Green is the blood oxygenation signal, and purple is the cerebrospinal fluid signal

After waking up, the major cycle is gone, and there is no way for the cerebrospinal fluid to rush into the brain in large quantities to complete an effective cleaning:

The corresponding author of the paper, Laura Lewis (“Lewis” for short), believes that this is because during sleep, neurons in the brain begin to synchronize activities, turning on and turning off together

　　The reason for this speculation is that EEG data shows that the circulation of blood and cerebrospinal fluid only occurs after the emergence of nerve rhythms:

　　When a large number of neurons stop firing together, there is no need for so much blood to transport oxygen, which gives the opportunity for cerebrospinal fluid to flow in

　　This discovery is very important.

　　When we are awake, neurons don't turn on and off at the same time

　　Only after falling asleep, when there is not so much blood in the brain, can the cerebrospinal fluid circulate freely and remove metabolic byproducts like beta amyloid

　　Previously, the development of drugs for beta amyloid has been in trouble frequently, and the in-depth research has also opened up new treatment ideas for the treatment and prevention of neurological diseases such as Alzheimer’s (Alzheimer’s disease) and autism.

　　Okay, after reading this tweet, everyone can wash and sleep.

　　From today

　　No longer stay up late