Want to remember an event more vividly? Try describing it to a friend. Or jotting down how it all happened.
A new study once again finds that reflecting on events immediately afterward helps us to preserve them in our memory —and this study helps explain how the process works.
Researchers at the University of Sussex and University College London found that the same region of the brain that's activated when we first experience a memory is activated again when we "rehearse" the memory afterward.
This region, called the posterior cingulate, helps us not only recall details of an event but also integrate those details into our knowledge, making it less prone to be forgotten.
To conduct their study, which was published in the Journal of Neuroscience, the researchers showed participants 26 YouTube videos about 40 seconds long that featured some kind of narrative element. After viewing 20 of the videos, participants were then given 40 seconds to relate either privately or out loud what happened in the video. They were not allowed that same time for reflection after viewing the remaining six videos.
The outcome? Participants remembered vivid details of the 20 videos they had rehearsed up to two weeks after viewing them. Meanwhile, they had largely forgotten the other six videos.
MRI scans of the participants' brains revealed that the more their brain activity synched up when watching and rehearsing the videos, the better they would remember the videos later.
The findings, particularly the MRI results, surprised lead researcher Chris Bird, a senior lecturer in psychology at the University of Sussex.
Reactivating an event
“Ours is the first study to show that specific events (e.g. a particular video) create patterns of brain activity that are later re-activated when that event is recalled,” Bird tells TODAY.com over email. "The amount of reactivation within the posterior cingulate predicts how detailed your memory for that event will be a whole week later.”
"We know that the posterior cingulate is important for memory — it is damaged early in Alzheimer’s disease," Bird says. "However, our results point to a specific role in storing internal representations of complex events."
The findings have implications for situations where accurate recall of an event is crucial such as witnessing an accident or a crime, says Bird.
It is no surprise that immediate rehearsal helps form the memory, says Dr. William Klemm, a senior professor of neuroscience at Texas A&M University who is unaffiliated with Bird's study. "This is a fundamental principle of formation," Klemm tells TODAY.com via email.
What's new about Bird's research, says Klemm, who has written several books on memory, is the idea that reactivation in the posterior cingulate predicts how well you will recall something during a later "retrieval."
Keep these memory tricks in mind
We can improve our ability to recall information by simply giving ourselves time to go through the information immediately afterward, the researchers say.
“If the goal is to remember an event, then I would recommend rehearsing it while you memory is still fresh," he says.
Bird suggests writing down what you can remember or describing the event to someone else. Or both.
“The other thing we know about memory is that it helps to recall things in different way," Bird says. "One way would be to describe everything to yourself, but another way would be to try and play back everything in your mind’s eye."
In fact, you may remember different things using different methods of recall.
One more interesting thing about memory and the rehearsal process — it works for the future, too.
"If you visualize yourself picking up a letter that you leave on the table by the front door, then you are more likely to remember to do so when you go out the house the following morning,” Bird says.