Brain Rules for Aging Well. John Medina
over everyone’s lifetime” (emphasis mine). Another study taking into account similar variables—this one involving more than fifteen hundred people ages twenty-one to ninety-nine—also found that people aged on a positive note. And if that were the end of the story, we could just whistle a happy tune, pack up our bags, and end this chapter. Turns out not everything about mood improves, and the boost does not last forever—or for everybody. Before we get to that, however, we have to figure out why, for so many, it lasts so long.
What Satchmo says
One of the most relentlessly upbeat songs of the late 1960s and early ’70s rock era was performed not by a rock group but by a jazz legend. It was Louis Armstrong’s interpretation of “What a Wonderful World”:
I hear babies crying,
I watch them grow;
they’ll learn much more
than I’ll ever know.
Armstrong then marvels at what a wonderful world it is. Some people took exception to this half-full glass of rosy-colored water. With the Cold War in full flower and the Vietnam War in hideous bloom, the world could hardly be called wonderful, right? Armstrong heard about these criticisms, of course, and before graveling it out at a concert one night, he announced this to the audience:
Some of you young folks been saying to me: “Hey, Pops—what do you mean, what a wonderful world? How about all them wars all over the place, you call them wonderful?” But how about listening to old Pops for a minute? Seems to me it ain’t the world that’s so bad but what we’re doing to it, and all I’m saying is see what a wonderful world it would be if only we’d give it a chance. Love, baby—love. That’s the secret.
Remarkable, coming from a man whose greatness endured large helpings of Jim Crow, using bathrooms and drinking fountains marked “Colored Only.”
It is Life 101: we’ll experience both positive and negative events over time. The same generation that witnessed the My Lai massacre also watched a man land on the moon. As the years roll by, however, our brains don’t process positive and negative information in a balanced way. Our desire for (and memory of) optimistic input gets more intense as we age, and we begin to experience life more as a wonderful world.
How do we know? The surprising initial finding of scientists was that older people experienced fewer negative emotions than their younger counterparts. Researchers such as Mara Mather, gerontologist at USC, and Laura Carstensen, director of the Stanford Center on Longevity, decided to investigate. Consistently, they found that older people’s brains paid more attention to positive stimuli than negative stimuli. And seniors remembered more details about the optimistic stuff, too.
One experiment involved younger people (average age twenty-four) and older people (average age seventy-three) gazing at happy and sad faces. Which would they pay the most attention to (“attentional bias”)? When the youngsters looked at positive faces, they scored 5 out of 25 on the bias scale; they scored 3 out of 25 for negative faces. This meant they were paying modest, fairly balanced attention to each. When seniors looked at the same faces, they scored 15 out of 25 for positive faces and –12 of 25 (yes, negative 12) for the not-so-positive faces. Nothing modest or equal there.
Researchers observed similar differences when they assessed that most dissonant note of aging neurons—negative memories. To understand these data, we need briefly to review how memory works. (We’ll have a more full-throated treatment in the memory chapter.) The important concept is this: brains don’t record life as if on a single reel-to-reel tape deck. Rather, many semi-independent memory subsystems exist—many types of tape decks, if you will—each responsible for recording and retrieving a specific domain of learning. Learning how to ride a bicycle, for example, uses a different neural deck than remembering an episode of Breaking Bad or recalling that Tony Bennett sang “Put on a Happy Face.” Your ability to recognize something you’ve seen before (recognition memory) uses yet another memory subsystem.
To test recognition memory, both younger and older populations were shown pictures of “positive images” and “negative images” (such as a person making a happy or a sad face). Younger adults recalled both at roughly equal percentages. Not so for older adults. Their recognition scores were 106 percent higher for positive images than for negative ones.
Researchers have noticed analogous changes for episodic memory (memories for events), short-term memory (now called working memory), and long-term memory (just what it sounds like). The phenomenon even has a name: the Positivity Effect. One reason older people report being happier is that they’re increasingly selective about what they pay attention to—and what they remember when they do pay attention.
Why all this optimism in seniors? After all, their joints begin to ache for reasons that become increasingly untreatable, friends begin dying off as if in a war zone, they forget why they went downstairs, and they quit remembering your birthday. Happiness is probably one of the many rewards the brain uses to keep us pro-social. Emphasizing positivity keeps depression away, buffering against suicide. People who are more positive toward us are more likely to lend us a hand in our old age—useful for survival.
There’s another pro-social reason seniors are happier. To explain it, I’ll turn to an Industrial Age Brit who would not be caught dead putting on a happy face. We’re going to talk about that quintessential grumpy old man, Ebenezer Scrooge.
Lessons from London
The most unsettling aspect of Dickens’s A Christmas Carol to me is that some of its nineteenth-century pages seem lifted straight out of a twenty-first-century geroscience textbook. As proof, I offer you a few degrees of Ebenezer Scrooge’s famous narrative arc. He starts as a miser about Christmas, as you know, and doesn’t change to Santa Claus until he finally confronts his death. What helps turn him away from the dark side isn’t a grave marker, however. (Presumably death is as much a concern to innocent Tiny Tim as to greedy moneylenders.) The change agents come gradually, from the types of things Scrooge observes as the ghosts force-feed him his biography. When Scrooge is young, his mind is on his newly minted career, the knowledge-based world of industrial-age banking—and his increasingly self-centered success. But when he is old and the Spirits have held sway, his priorities have been turned upside down (or, rather, right side up). He exchanges the cold, knowledge-soaked world of accounts receivable for the warm, emotion-soaked earthiness of human relationships.
Here, data and Dickens meet, for this exchange—minus the ghosts—is exactly what happens to our brains with age. We, too, shift from paying off college debt and other financial priorities to playing with grandkids. This, on average, makes us happier. The delightful metamorphosis stems from both nurture and nature, each of which deserve a hearing.
In your youth, your brain fools you into believing you’ll live a long time, if not forever. This is an attitude positively shackled with social consequences—ranging from whether you commit to retirement savings or sign up for health care. (Insurance companies often call people in this age group “the immortals.”) You are also at the starting gate of your career, and so you see knowledge-based pursuits as your top priorities for future achievements. Ditto for your relational successes. Anyone who’s been married, had children, or experienced both understands how much extra knowledge you need to be successful.
All that changes with age. You now have a few more miles on your biological tires and greater knowledge about how the world works. You hardly need three ghosts to realize you were wrong and won’t live forever. I remember first discovering this when I wrote down the number of books I wanted to read before kicking the bucket. I calculated the time it would take to read them and realized I would need to live more than 180 years to finish. And that’s if I didn’t do anything else but read books. While that is surely a vision of heaven for me, I have, unfortunately, other things to do. Aging forced me to prioritize. And since I knew I wanted to spend more time with my family than with Dickens, or any other author, I could sense something warmly relational shifting beneath my behavioral feet.
This shifting is consistent with the research literature. When you truly realize you