Science

3 ways that your memory stays sharp even as you get older

Oct 4, 2018 /

While overall memory declines as we age, that’s far from the end of the story. In fact, there are certain things older people continue to remember quite well, says researcher Alan D. Castel.

Our memories are our identities, and at my lab at UCLA, I’ve worked to understand how we remember what matters to us, especially as we age. Memory decline is one of the first things that concern people about growing older — it can start after the age of 20, so being more forgetful when you are 60 or 70 is often normal. And while a vast amount of research has shown the deficits that accompany aging, it’s far too simplistic to say that the elderly have impaired memories. In fact, there are many things older adults remember quite well. Here’s a look at a few of them:

1. Older people tend to remember the essentials.

A great deal of memory research focuses on what might be considered by some of us to be mundane — word lists, face-name pairs, studying and being tested on pictures — and it’s unclear why this might be important to remember. But how about things that are of real concern or interest?

Imagine you’re packing for a trip. You want to make sure you’ve put in the most important items, the ones that would be extremely costly and/or inconvenient if you forgot them (e.g., your passport, your credit cards). While I wish we could have followed people on their vacations to see what they left behind, we created an experiment to examine this in the lab. We presented subjects with 20 possible items that you might pack on a trip (e.g., medications, passport, sunscreen, toothbrush, phone charger, deodorant, swimsuit, sandals). When we later asked them to recall the items, the older adults (average age was 68) recalled more of the items that they felt were important than the younger adults (average age of 20.4), even though they remembered fewer items overall. We’ve since done other studies showing older adults will have a greater memory for important medication side effects from a long list and for a grandchild’s dangerous allergens than younger adults.

We did another experiment when we came up with a list of words to remember. Some were more important and paired with higher point-values or rewards, while others were less important and associated with lower point-values or rewards. The goal was to maximize one’s overall memory reward — to do that, you needed to remember the words paired with the highest values. We found that older adults remembered fewer words overall but recalled just as many of the highest-value words as younger adults.

2. Older people tend to remember what they need to do in the future.

Sometimes the most important things for us to remember involve future actions. This is called “prospective memory” — and it might take the form of remembering to take medications at a certain time tomorrow, or paying a credit card bill on a particular date or else we’ll get penalized. While prospective memory might be worse in older age, there are important exceptions. Researchers have found a “prospective memory paradox”: despite older adults doing poorly on laboratory tasks of prospective memory, they fare well in the real world.

For example, in research studies older adults may be asked to perform a future task such as “When you see the word ‘president’ on the next page, please raise your hand.” Sometimes they get so focused on reading that they forget to react when “president” appears — but does that mirror the forgetfulness of not taking one’s medication at noon in 2 days? As many of us know, older adults have often developed strategies to prompt their prospective memories, like putting their wallet by the front door or their medications by their eyeglasses. To bridge this gap between lab-based prospective memory tests and real life, one study asked people who came to the lab to mail back postcards every week; researchers wanted to determine how younger and older adults would compare in remembering to do this future-focused task. To their surprise, it was the older adults who diligently mailed in the postcards each week.

Of course, some older adults remember to do things the old-fashioned way: they write it down in a calendar they consult every day. When I called then-97-year-old John Wooden, retired from a legendary career as a basketball coach, to schedule an interview, he wrote it in a calendar. Then, he called me the day before to confirm I was still coming to see him — he was reminding me!

3. Older people tend to remember what intrigues them.

Humans are curious from an early age. My young son loves the adventures of the mischievous Curious George and of learning about the world. Our curiosity blossoms with age, but we typically become interested in different things as we get older. After all, Curious George is not the favorite bedtime reading of most adults.

To test your own level of curiosity and memory, read the following trivia questions, decide how interested you are in learning the answers (on a scale of 1 to 10, with 1 being not interested at all, and 10 being extremely interested), and then try to come up with answers (the answers are at the very bottom of this article):

What mammal sleeps the shortest amount each day?
What was the first product to have a bar code?
What was the first nation to give women the right to vote?

These are fairly difficult trivia questions, and some are probably more interesting to you than others. In one study done in my lab, younger and older adults were given questions like those that you just read. Much like those, all of the queries were chosen such that we guessed almost none of the participants knew the correct answers. Afterwards, the subjects gave each a curiosity rating — showing how interested they were in learning the answer. They were then told the answers. A week later, the same subjects were presented with the same questions and asked to recall the answers. It was the older adults who remembered the ones they were more curious about — and they forgot the less interesting ones. The younger adults didn’t show this pattern.

There’s a certain pleasure in recalling trivia and absorbing new information about the world. I’ve noticed the most popular games at senior centers and retirement communities often involve this kind of random knowledge. People sometimes worry about having too many stray facts in their minds. But even though trivia may appear to have little useful value, the fact that it continues to arouse curiosity — and sticks in older people’s minds — shouldn’t be discounted.

4. OK, older people may forget what they’re doing in a particular room, but they can jog their memory.

Our surroundings can influence how we remember things. Have you ever found yourself in the kitchen and not had the faintest idea what compelled you to go there? This is a common occurrence for everyone, but especially for older adults. Some research suggests that walking through doorways or crossing physical boundaries may actually trigger forgetting. When you move from one place to the next, the doorway leads to a new environment that does not provide the necessary cues to remember what you were doing in the other room. As you enter the new room, your brain must either keep in mind or re-create what you were thinking when you were in the earlier room — but our minds often wander as we go to another room or we start thinking about something else.

The best way to remember what you need is to walk back into the first room where you originally had the thought of why you needed to go to the other room. The context of that original room can trigger your original intention. In addition, walking is one of the best ways to keep your memory sharp. With enough time and walking, you’ll find the memory eventually comes back.

P.S. But don’t get too hung up on what you can and can’t remember.

Our beliefs about our memory can be very influential. In fact, many of us have negative beliefs and expectations about aging’s impact on the brain. This kind of “stereotype threat” can make people perform stereotypically — in a way that is consistent with what they think is expected of them. Stereotype threat has been examined to determine if it causes older adults to underperform on tests of memory. Labeling something a memory test, or asking people to come to a memory study, does appear to invoke anxiety, and research has shown that renaming it as a “wisdom test” (and then administering the same memory test) leads to better performance by older adults. So, the next time you start to worry about forgetting a world capital or a famous actor’s name and wonder what this means about your brain and your memory, try not to sweat it.

Note: The research covered here involves mostly healthy older adults who report memory changes in older age. However, if you experience more frequent and concerning memory problems, you should consider consulting a neurologist.

Answers to trivia questions: giraffe; Wrigley’s chewing gum; New Zealand.

Excerpted with permission from the new book Better With Age: The Psychology of Successful Aging by Alan D. Castel PhD. © 2019 Oxford University Press. All rights reserved.

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