Why is it that you can perfectly recite the words to *NSYNC’s “Bye Bye Bye,” but can’t remember the title of the new TV show you started watching on Netflix and wanted to tell your coworker about?

We remember things because they either stand out, they relate to and can easily be integrated in our existing knowledge base, or it’s something we retrieve, recount or use repeatedly over time, explains Sean Kang, PhD, assistant professor in the Department of Education at Dartmouth College, whose research focuses on the cognitive psychology of learning and memory. “The average layperson trying to learn nuclear physics for the first time, for example, will probably find it very difficult to retain that information." That's because he or she likely doesn’t have existing knowledge in their brain to connect that new information to.

And on a molecular level neuroscientists suspect that there’s actually a physical process that needs to be completed to form a memory — and us not remembering something is a result of that not happening, explains Blake Richards, DPhil, assistant professor in the Department of Biological Sciences and Fellow at the Canadian Institute for Advanced Research.

In the same way that when you store a grocery list on a piece of paper, you are making a physical change to that paper by writing words down, or when you store a file on a computer, you’re making a physical change somewhere in the magnetization of some part of your hard drive — a physical change happens in your brain when you store a memory or new information.

“So the ultimate question, at the cellular level, as to whether or not a memory gets stored [in the brain] is does that process actually complete properly,” he explains. “Do all of the molecular signals get transmitted to ensure that that cell changes physically?”

So there are strategies for better organizing what may at first glance appear to be unrelated information to connect it to what we already know to help us better remember things, according to Kang and others. But as far as changing the physical processes in the brain that make memories stick, there’s likely not much you can do now to affect that, Richards says.

And that’s probably a good thing, he adds.

There may be a reason our brains forget things

In a recent paper, Richards and his colleague Paul Frankland, PhD, senior scientist at The Hospital for Sick Children and Fellow at the Canadian Institute for Advanced Research, looked at previous studies that have investigated the physical changes in the brain associated with memory — and why sometimes that process completes and sometimes it does not. “We found that there’s a variety of mechanisms the brain uses — and actually invests energy in — that undo and override those connections, ultimately cause us to forget information,” Richards says.

And that would mean that some “forgetting” is actually a very natural and normal process, rather than a “failure” of our memory, Richards says. “Our brains may want us to remember the gist of what we’ve experienced because that will be most adaptive for making decisions in the real world.”

For example, let’s say you remember a friend’s phone number, but that friend moves away and gets a new phone number. Remembering the old number becomes useless and may make it more difficult to remember your friend’s new number.

“It’s not the case that as much forgetting as possible is good, obviously,” he says. “But at the same time it may not be the case that as much remembering as possible is always the best course either.”

What you can do to help make memories stick

Sure, some of what determines how well you remember things are the genes you’re born with, Kang says. But training can definitely plays a role in memory, as is the case for people who compete in memory competitions, he adds. “No one suddenly wakes up one day being able to memorize 60,000 digits of Pi.”

If you want to hone your own skills (whether that’s for memorizing Pi or better remembering names or facts), here’s what might help:

1. Get a good night’s sleep

Decades of research support the fact that sleep is a critical time when memories consolidate and get stored. And that means missing out on sleep — or high enough quality sleep — can compromise some of those processes. The National Sleep Foundation recommends getting between seven and nine hours of sleep each night for optimal health and brain function.

2. Exercise regularly

What is exercise not good for? It’s important for your heart, your mood, your sleep and your mind, particularly the part of your mind involved in memory. In one study in middle-age women with early signs of memory loss, starting a program of regular aerobic exercise actually increased the size of the hippocampus (a part of the brain known to be involved in the memory storing process) and improved verbal memory and learning scores when the women were tested.

And a new 2018 guideline from the American Academy of Neurology recommends regular exercise as one of the things people with mild memory problems should do to help stop those problems from getting worse or turn into serious neurological disorders like Alzheimer’s disease and other types of dementia.

3. Repeat or re-learn the information later

Psychologists and others call this one the spacing effect. The idea is that the more you re-learn or remind yourself of information again and again spaced out over time the better you’ll retain that information.

Perhaps you first learn about an Olympic figure skater’s difficult upbringing watching a news clip about his story; then a day or so later you read an article about that same skater; and then a few days later a coworker starts telling you about the same figure’s skater story. Repetition helps make that story stick in your head — and so does the fact that you re-learned that information on different days in multiple different settings, Kang explains. (Multiple studies show that there is indeed merit in this approach.)

“The richer the contextual details associated with a particular memory, the greater the number of possible cues that could be helpful in evoking the memory later,” Kang says.

4. Test yourself

People often think testing is useful because it tells you what you know and what you don’t. But the more important power of testing is giving you practice retrieving information you’ve learned and establishing that connection in the brain, explains Rosalind Potts, PhD, teaching fellow at the University College London, who researches how cognitive psychology applies to education.

For example, in one study that tested a group of students on new information they had learned one week earlier, students who were also tested on the new information immediately after learning it outperformed students who were simply instructed to study the information on the test they all took one week later.

5. Put the information in your “memory palace”

Some say this approach dates back to ancient Latin scholars, but it’s also been proven in much more recent literature to work. The idea is if you want to remember something, such as a shopping list or a code, you visualize those items or numbers in different rooms of your house (or some other physical place you are very familiar with).

The “memory palace” approach (also called the “Method of Loci”) has been studied extensively in psychology. Research shows it can be more valuable in terms of remembering than having more intellectual capabilities in the first place, and that it can be more effective for remembering than straightforward repetition and memorization.

6. Use a mnemonic device

It’s easier to remember things that relate to knowledge we already have because we connect it to what we already have stored in our memory, Potts says. That’s why mnemonic devices work — they create a bridge between two pieces of information.

“So when we want to call that memory to mind, there are lots of different possible routes to it,” she says.

If you want to remember the meaning of the Spanish word “zumo” (“juice” in English), you might conjure up an image in your head of a sumo wrestler drinking juice. When you hear the word “zumo,” you might then think of that sumo wrestler drinking his juice and remember the meaning of the word.

7. Pay attention

Sure, it’s obvious. But concentration is important if you’re trying to learn something, Kang says. “If you don’t pay much attention to the information, the likelihood you encode that in your long-term memory is low.”

For example, he says, how many Americans could accurately draw the details of the dollar bill, even though they likely look at it all the time?

8. Make it relevant to your life

Based on the neuroscience explanation of how memory works, if you really want to remember something, your best bet is trying to connect it to some other part of your life or a topic you already know, Richards adds. “Figure out some other facet of life why it’s relevant — and use it.”

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