Your brain is learning automatically when you sleep! Here comes the first human experimental evidence: accelerate playback 1-4 times, and the effect of deep sleep stage is the best

Dream morning From the Aofei temple
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Read a few pages or words casually before going to bed , When I woke up, I was impressed .

I don't know if you have had similar experience ？

Scientists have always wanted to study this phenomenon , But it has been restricted by technical conditions before , It is difficult to collect weak signals of neural activity in the human brain at night .

With the recent Wireless data transmission of brain computer interface Technological development , The chance finally came .

In an experiment involving volunteers , For the first time, researchers have obtained the motor cortex of the human brain during sleep “ replay ” Direct evidence of daytime activity .

Thesis work 、 Harvard Medical School Daniel Rubin Express ：

What we found was incredible , He ( volunteer ) Basically, I practiced all night while I was sleeping .

Relevant papers have been published in well-known journals in the field of neuroscience The Journal of Neuroscience On .

The brain speeds up learning while you sleep

The volunteer's code name is T11, Unfortunately, he was paralyzed by spinal cord injury .

He implanted BrainGate The invasive brain computer interface electrode of the project team , And last year IDEO typing Studied T5 The old man used the same set of equipment .

In this experiment ,T11 You need to play a simple video game during the day ：

First observe the order in which the colored areas light up , Later, control the cursor to move in order according to the recall .

This is a classic task in BCI research , The pattern of neural activity is easy to capture and recognize , It has also appeared in relevant research for many times before .

Ten days in a row ,T11 In the afternoon 13:45-16:00 Do the training , evening 23 Sleep until the next morning 9 spot .

During the training , BCI can decode and record the neural activities of his cerebral motor cortex in real time .

T11 I was not told the details of the experiment , Just do recovery training as usual , Go to sleep at night as usual .

But in these ten days , The researchers compared the data recorded by the brain computer interface when he slept with the data during the day .

After processing the data by means of Kalman filter, it is found that , Nocturnal neurons replay daytime training at higher frequency intervals than expected .

T11 The firing pattern of neurons during sleep is highly consistent with that during daytime training , There were even several times when they were identical .

△ In the morning 0:50 Start with the data and visual presentation

The scientific name of this phenomenon is Offline replay  （offline replay）, It has been previously verified in mice and humans during daytime rest .

However, it is the first time that playback during human sleep has been observed .

And the data display , Playback at night is faster than during the day Hurry up 1-4 times .

That is to say, when you are asleep , Your brain is not just automatically learning what you learn during the day , Or speed up your study .

And you don't know anything about it .

The harder the task is , The more active the brain is

There have been a series of studies before , It was verified that the neural activities of hippocampus and neocortex in mouse sleep could practice maze walking .

And the similar off-line replay phenomenon during human daytime rest .

Combining these findings with experimental results , The researchers came up with an idea ：

Replay learning may be a retention mechanism that spans multiple brain regions , Including semantics 、 Navigation and motion control system . It further supports the role of sleep in memory consolidation .

besides , The study also confirmed several important findings ：

First of all , The time of playback is mainly in the biological sense Slow wave sleep （Slow-wave Sleep）, The more common name is Non rapid eye movement stage （Non-REM Stage）, Or deep sleep .

second , Replay activity is related to the hippocampus Sharp ripples （Sharp Wave Ripple） Highly correlated .

Sharp ripples are rapid bursts of synchronous activity of neurons , Will form a high-frequency oscillation .

△ The relationship between playback and sharp ripples

Third , The more difficult it is to practice during the day , The more intense the playback activity during sleep .

In future plans ,BrainGate The alliance's research team intends to systematically change the task difficulty , Do more in-depth research .

BrainGate The alliance consists of clinicians 、 Neuroscientists and Brown University 、 Harvard Medical School 、 Massachusetts General Hospital and other institutions jointly launched , The goal is to use brain computer interface technology to help patients who have lost the ability to move their limbs due to neurological diseases or injuries .

One More Thing

Since the brain is consolidating memory during deep sleep , So during rapid eye movement （ That is, the stage with the most dreams ）, What is the brain doing ？

before Science The last paper explained this .

Rapid eye movement period , Those responsible for the secretion of melanin aggregation hormone in the hippocampus MCH Neuron Will help the brain Take the initiative to forget unimportant information .

Because dreaming mainly occurs during rapid eye movement , here MCH Neurons are active , This is one of the reasons why the content of dreams can be forgotten after waking up .

that , Have you ever woken up , I have remembered all the things I read the day before ？

Address of thesis ：
https://www.jneurosci.org/content/42/25/5007

Reference link ：
[1]https://neurosciencenews.com/motor-replay-sleep-20906/
[2]https://www.science.org/doi/10.1126/science.aba0672
[3]https://royalsocietypublishing.org/doi/10.1098/rstb.2019.0655
[4]https://www.science.org/doi/10.1126/science.aax9238