From chronic insomnia help audio books, podcasts, and sleeping pills. If you load books on all night, they will gradually penetrate into dreams. And the funny thing is, sometimes you can even remember what he heard in the morning. Scientists have long wondered whether to be conscious, to remember. It seems that Yes — in the end, all of our precious memories are formed during waking hours, when consciousness in the work.
However, a growing body of research on the topic that when we slip into unconsciousness during sleep, we lose the ability to remember new material. That is, turn on the playback dictionary of new words, the unconscious brain will learn these words — without any work or awareness, even upon awakening.
The study, recently published in the Currently Biology, suggests that the idea of learning during sleep has roots. Scientists conducted an experiment with a group of 41 people who speak the German language, and found that the brains of participants can absorb the vocabulary of made-up language and to attach these words to the German values during sleep.
This, of course, far from learning a brand new language, including syntax, dormant. But upon awakening, participants asked if marked made-up word more than a Shoe box (Yes, it’s a weird test) and the participants answered correctly with a much higher chance — not knowing that they had previously encountered the word.
“In the study we found that the sleeping brain may in fact encode new information and store it for a long time. Moreover, the sleeping brain is able to create a new Association,” says study author mark Zust the University of Bern.
Sleep and memory
We often think of sleep as downtime. But it’s not.
A recent study showed that sleep helps the brain clean up, wash the toxic molecules which eventually can lead to Alzheimer’s disease.
More importantly, sleep also reorganizes memories. At certain stages of sleep the brain replays memories in an accelerated mode: the neurons responsible for storing memories, is activated again as the network, essentially teaching the brain to memory. This loss helps us to cram important lessons and life experiences in a more permanent storage in the brain. Meanwhile, tangential memories — those that primarily do not deserve special attention, are erased, to open up more space for storage.
Part of this night work can be captured by direct measurement of neural activity in the brain of rodents. Put the mouse in the maze new day, and the neural network activated during encoding of memory, will work at night.
From these studies on rodents scientists discovered that the hippocampus — the area in the form of a seahorse, hidden deep inside the brain — is associated with the outer layer of the brain cortex, during sleep, through the waves of activity that can be measured with a device EEG.
Training in a dream
In this study, researchers took 41 German-speaking volunteers of both sexes. Instead of teaching them conventional language, the team made up of pseudoloma, each of which was associated with a specific value to ensure that one of the participants had no contact with a new language.
Instead of having to say the words, when the volunteers slept, the scientists decided to target a specific sleep period: the so-called “peaks” during deep sleep, usually not associated with dreaming.
During deep sleep, neurons coordinate their activity during short periods of time before again falling in the period of inactivity to fall on the chart. Two of these conditions are cyclically replaced every half a second.
“We assumed that the peaks of the slow waves contribute to the encoding of sleep, because the peaks demarcate periods of relative neural excitation,” explain the authors.
When the volunteers fell asleep, each of them was a device EEG for monitoring brain function, and scientists began to play word Association using in-ear headphones.
For example, invented the word “Topher” meant “key” and “Guga” — “elephant”. Each pair of words was reproduced four times, in accordance with the rhythm of the sleeping brain, so that the second word coincides with the peaks of the waves. All sleeping brain heard about 36 different pairs of words in more than 146 reps.
“The moment when he played the second word was important, because at this point you can form an Association between one word and another, and hence neural plasticity must be optimal,” the authors explain.
Upon awakening volunteers, the researchers showed them pseudoloma and asked to portray, whether the designated object is smaller or larger than a Shoe box — as a way to penetrate the unconscious memory.
“Implicit memories are difficult to formulate explicitly. We had to gain access to the unconscious, implicit knowledge through the questions about semantic aspects of these new words,” said Zust.
15 participants also got brain scans using fMRI at the time of the attempt decision making.
It is noteworthy that when the second word in a couple of words coincided with the dream state in deep sleep, the participants were able to correctly describe the made-up word 10% above chance.
“If you are “pictum” and “bird” the sleeping people, their brain can make new connections between the well-known concept of “bird” and completely new and unknown word “pictum,” said Zust. “This track in my dream remains during wakefulness and can affect how you react to “victum”, even if you think you’ve never encountered this word. It is implicit, unconscious form of memory — like “gut feeling”.
By studying the data, scientists found that getting into peak state at the time of submission of properties correlates with better remembering after awakening.
This explains a number of contradictions in previous studies of sleep. The authors explain: “the presentation of words on EEG sleep was decisive for the success of the encoding of the dream.”
Looking at the student, but sleeping brain, scientists have discovered that the hippocampus and the area of the brain usually associated with language learning were also active during learning during sleep.
It’s very contrary to everything we know about learning in the hippocampus — we believe that it is active only in the waking state.
“These structures of the brain, apparently, mediate memory formation regardless of the prevailing state of consciousness — the unconscious during deep sleep, the conscious during waking hours,” said Zust.
Those who have thought about creating a device for “learning during sleep”, it is understood that the idea of introducing an entirely new vocabulary during sleep remains highly controversial. In the end, the dictionaries based on knowledge, not on intuition. Moreover, scientists still do not know whether active learning during sleep to prevent a more prominent role of sleep in the consolidation of daytime memories.
“The practical significance of the unconscious encoding during sleep for further study after you Wake up will ultimately depend on the possible improvement of the first session encoding is sleep learning,” says scientists.