How Sleep Increases Memory Recall
Sleep is one of the core pillars of health when it comes to your brain. The way it affects areas of cognition and overall health simply can’t be understated.
Science is still uncovering the many ways in which sleep affects our lives. One of those all important areas is memory. The two go hand in hand. And because memory is a key function in learning, it has a big impact in your life.
Research on the relationship between memory and sleep is becoming more clear. Studies have shown how it helps in memory formation. Recent findings, though, say it can do more than play a role in how we store memories. It can also affect how easily we can access the information we’ve learned.
So let’s see what science has to tell us about how sleep increases our memory recall.
The evidence from previous research is pretty clear that memories become stronger while we sleep. But new research from the University of Exeter and the Basque Centre for Cognition has revealed that sleep may be able to grant us access to memories that we may not have been able to recall while awake.
Here’s what they did. They gave participants a list of made up words to look at. After looking through the new terms, scientists immediately tested subjects to see how much they could remember.
Next they separated the people into two groups. One group slept for a period of time, while the other group remained awake for the same amount of time. Following the period of sleep – or wakefulness – they were tested on the words again.
The scientists found that the group that slept could recall words during the second test, that they couldn’t recall when they were tested initially. When compared against the results of the group that stayed awake, it seemed that the sleep was instrumental in helping recall the lost information. The scientists noted that sleep helped the recall more than preventing actual memory loss.
Their results have been published in the journal Cortex.
The scientific community isn’t quite sure what is driving the relationship between memory and sleep just yet. They just know that it helps memory formation and now accessibility.
But they have some guesses.
Dr. Dumay, one of the authors, believes the hippocampus is the driving force behind what makes the memories easier to recall. When we sleep, he believes that the hippocampus causes the parts of the brain – which originally formed or captured the memory – to fire.
This would sharpen the memory by strengthening the original neurons associated with it.
Sleep as a Study Aid
So you may want to rethink the “stay up all night before the exam” type study session.
Getting some sleep before the test not only strengthens the memories, but it makes them easier to access. When can help you access important facts and information to questions when the clock is ticking on test day.
Dr. Dumay, the author of the study, drives home this importance by saying:
“Sleep almost doubles our chances of remembering previously unrecalled material. The post-sleep boost in memory accessibility may indicate that some memories are sharpened overnight. This supports the notion that, while asleep, we actively rehearse information flagged as important.”
Another study from the University of Notre Dame confirms this strategy. They found that getting some z’s right after acquiring information can help you retain two different types of memory.
Studying is good. But studying effectively is better.
And in the future, you may want to try spreading your study sessions out over the course of the semester. Instead of just the night before your test.
Image: Gavin Clarke