We assume that the brain is doing something while we’re sleeping because we dream. But is dreaming all that is going on up there? Are dreams just random static coming out of our sleeping brains, or is our brain doing things behind our backs while we are sleeping?
When we get tired, sleeping gives us time to rest and rebuild. It seems logical that the brain would follow a similar pattern. After all, don’t we get tired of thinking and want to turn the process off after a while? Sleeping sounds like the perfect way for our whole system, including our brain, to check out and take a break.
Not so much!
When we are sleeping, our brain is extraordinarily active. As it turns out, much of that activity helps the brain to learn and remember. Sleeping is involved in the learning and memory process in several important ways. Let’s look at 3 of them.
Sleeping helps people recover forgotten skills
A study conducted by The University of Chicago concluded that sleeping helps the mind learn complicated tasks. It also helps people recover knowledge they thought they had forgotten over the course of a day.
For example, in one study, after learning how to play a video game much of that skill was lost within 12 hours. Amazingly, after a night’s sleep those lost abilities were restored. Why does this happen? It’s a consolidation process that brain goes through while we are sleeping.
Sleeping consolidates learning by restoring what was lost over the course of a day, and by protecting against further loss. These findings suggest that sleeping plays an important role in learning specialized skills, and in stabilizing and protecting memory. This consolidation process may also help with language skills like reading and writing, as well as eye-hand skills such as tennis.
Sleeping selectively preserves emotional memories
A recent study offers new insights into the specific components of emotional memories. It suggests that sleeping plays a key role in determining what we remember – and what we forget. Findings show that sleeping helps the brain to selectively preserve and enhance certain aspects of a memory. Those with the greatest emotional value are enhanced, and simultaneously, those of lesser value are downgraded.
Emotional memories usually contain highly charged elements – for example, the car that sideswiped us on the ride home. These memories include some elements that are only vaguely related to the emotion. For example, the name of the street we were traveling on, or what store we had just passed. Evidently, the individual components of an emotional memory become ‘unbound’ during sleep. This enables the sleeping brain to selectively preserve only that information which it deems worthy of remembering.
Sleeping helps us remember the sequence of events
We may have vivid memories of past events, but how do we remember the order of events? Until recently, it has never been clear how the brain keeps track of the chronological sequence in such memories. New research has confirmed that long-term memories are formed while we are sleeping. This is accomplished by the brain replaying the memories of our daily experiences during the night.
So, sleeping not only strengthens the content of a memory, but it also reestablishes the order in which those events took place. These findings show that it is the sleep associated consolidation of memories that helps establish our memory of events in chronological order. Something that we might not have been able to recall without this process.
The importance of sleeping
There are several different types of memory. There is declarative memory which includes retrievable, fact-based information. There is episodic memory which focuses on events from your life. Finally, there is procedural memory which allows us to remember how to do something. Researchers have designed ways to test each of them. What have they found?
In almost every case, no matter which type of memory was involved, one fact remained constant. After first learning the task, sleeping on it improves performance. It’s as if our brains squeeze in some extra practice time while we are asleep.
Why is all this important? Some sleep researchers believe that for every two hours we spend awake, the brain needs to spend an hour sleeping. This sleep time is used to figure out what all these experiences mean. Clearly, sleeping plays a crucial role in helping us to grasp the meaning our own lives.
What good is knowledge that can’t be remembered?
We live in the age of information overload. There is more information in one Sunday edition of a big city newspaper than the average person took in during their entire lifetime 200 years ago. On top of that, people are trying to get by on much less sleep. This is a dangerous combination that could lead to accelerated loss of memory as we get older.
Are you having trouble making sense out of your life? Do you find yourself forgetting things more often? Is it taking longer to learn new skills than it used to? Why not sleep on it and see what happens.