Like you sit back, relax and simply do not think about anything?
It may be a good reason why your mind wanders, even when you try to disconnect: your brain never really rests.
And contrary to popular thought, daydreaming may be beneficial.
For many years, neuroscientists were based on the notion that our brains work hard when we have to do a specific task and off when they are not mentally stimulated.
From there, the experiments in which volunteers were asked to perform a task -Press a finger, do mental arithmetic, look evocadoras- photographs while their brains were scanned.
The scanner shows which parts of the brain become more active during exercise and which less. Thus, it is possible to detect how the brain controls our behavior.
Neuroscientists often perform tests to explore brain activity in a variety of different tasks.
After each exercise, they must find a way to return the brain to a neutral state and that is usually done by asking the person to stare at a white cross in the middle of a black screen.
To stop thinking about something in particular, the theory is that the brain should essentially disconnected. The problem is that it does not.
The first sign of a brain at rest is surprisingly active arose two decades ago, when Bharat Biswal preparing his doctorate at the Medical College of Wisconsin
Investigating ways of getting a purer signal a brain scan, Biswal noted that the brain at rest is not doing nothing.
And scanners appeared to show that this was a really coordinated effort.
In 1997, an analysis that included the results of nine studies of brain scans revealed another surprise.
Gordon hoped his analysis Shulmen contribute to identify the network that is activated when people are paying attention.
Schulamn noticed that, consistently, some areas of the brain became less active when the rest period ended and the activity began.
The idea that the brain never rests slow to take hold, but currently almost 3,000 scientific papers have been published about the surprisingly active "resting state" of the brain.
Some question the term for the same reason that the brain is not resting at all and prefer to speak of "default neural network" (RND), areas of the brain that are still active when we are apparently idle.
The big question is: why the brain is so active rest?
Although there is no agreement. Perhaps it is because different parts of the brain are simply rehearsing work together.
Perhaps the brain remains active as a car stopped in case you need to act suddenly.
But it is possible that these vagaries of the mind and replays of our day play a crucial role in helping to consolidate our memory.
We know that our dreams appear to have a role in organizing our memories, there is now evidence that this also happens during the day (at least, it was found in rats).
We also know that when the mind wanders, often focuses on the future.
All three main areas of the brain to imagine the future are part of the default network.
Almost it seems that, being unemployed, our brain is programmed to look to the future.
Difficult to investigate
Moshe Bar, a neuroscientist at Harvard Medical School, believes that daydreaming essentially creates ideas of events that have not happened.
That gives us a strange set of "past experience" that we can use to help us decide how to proceed if dreams do occur.
For example, many air travelers have imagined what would happen in a plane crash. The idea is that, if it happens, the memories of those dreams of previous flights help the passenger to decide what to do.
However, the idle state is not easy to investigate. As some cognitive psychologists have noted, just because a person is lying in a scanner we can not be sure that they are absorbed in their introspective thoughts.
They might be thinking about the sounds of the scanner and what happens around them. Therefore, there are many unanswered questions about what happens when our mind wanders.
They Are, for example, the fantasies we experience when we tried unsuccessfully to concentrate on our work at different when we deliberately try to disconnect?
A study published earlier this year suggested that everyone could experience the resting state in the same way just slightly distant.
Researchers conducted a detailed brain scans of five people trained to remember their mental at the sound emitted by a computer ramblings study.
The researchers found significant differences between the fanciful thoughts and experiences of each person.
In September researchers at the University of Oxford used scanners Project "Human Connectome" the brains of 460 people at rest to explore what parts of the brain communicate with each other when we are resting.
It is as if parts of the brain remain connected when our mind wanders, just in case you need them for something "
Again, the results hinted personal differences in the resting state, in this case linked to the skills and experiences of life.
The strength of the connections between the different parts of the brain varies according to the strength of the memory of a person, his years of education and physical resistance.
It is as if parts of the brain remain connected when our mind wanders, just in case you need them for something.
From the scientific point of view, the discovery that our brain is never truly rest could help us understand an ancient mystery: why the brain uses 20% of the body's energy, whether for activities should need only run 5%?
Marcus Raichle neuroscientist defined as the 15% absent the "dark energy" of the brain and resting state activity could be partially responsible for this discrepancy.
The discovery from sleep also has the potential to change the way we feel about our brains.
We know how difficult it is to empty our minds, which have a frustrating tendency to wander even when we want them.
However, the picture that is opening suggests that quirk may be beneficial, even if it ensures that we finish one task at a time.
In other words, maybe it's time to celebrate the virtues of having an idle mind.