Brain During Sleep Experiment

So what does happen with our brain during sleep?

Researchers found that in brain during sleep, there are activated the same brain regions that were active during the events experienced during the day. The brain takes these events at a speed of six to seven times bigger than the speed during the events throughout the day.

Moreover, there is the possibility that this learning process is linked, which could open the way to improve traditional methods of learning.

Your brain doesn’t rest when you sleep. While you sleep last night, some parts of your brain worked, resuming the day’s events in a process that could be related to memory consolidation. In fact, the resumption of the previous day’s events could occur at a rate several times higher than the events that took place in reality.

The researchers implanted electrodes in the brain of mice, following the work of a large number of neurons (nerve cells up to 120) from the median prefrontal cortex (the brain region responsible for organizing thoughts and actions), while the animals had accomplished a certain task. The team monitored the daily activity of mouse brain for several weeks, while they managed to finish a task involving exercise for 50 minutes and then slept from 20 to 60 minutes.

Using 2 different methods – comparing activity between pairs of cells and follow the pattern of neurons targeted the entire population, the team noted that some segments are activated when mice were exercising they were reactivated in brain during sleep.

“We looked at them and I was surprised to see that there are many similarities”, said David Euston, research assistant at the Department of neural system, from the faculty of Medicine, referring to both active neural segments during the day and at night.

Not only that the same patterns were reactivated during sleep, but the speed with which worked six to seven times higher than when the mice had fulfilled the task. “During behavior, when in fact interact with the world, the brain has to work at the same speed with the rest of the body works”, said Euston. “Brain during sleep can function more quickly when the behavior is not restricted”.

This replay of previous day’s events was already shown in the hippocampus, episodic structure involved in memory and in the visual cortex, where sensory information is processed on the spot. Euston believes that the process could be related to plasticity, strength and weakness of connections between nerve cells with a role of learning.

“One way to improve memory is to resume information several times”, said Euston, referring to a single sequence of neural activity, which is responsible for learning. Through their multiple repetitions, the brain strengthens the connections between neurons, thus improving memory.

Mayank Mehta, professor assistant of neuroscience department at Brown University, says that discovers are interesting, but is skeptical about the assumptions on which it is based. “Is this consolidation or deletion?” asked Mehta, referring to the fact that if the work is truly ghostly “filing” memory, or is able to “clean sheet for more information to fit”. “In term of behavior, both processes can help”, said Mehta.

Euston said that the team will try to determine whether this reveal of events, made by the brain during sleep is related to learning. If so, said he, models should be resumed stronger when animals have just finished tasks related to learning.