Successful Aging: A Neuroscientist Explores the Power and Potential of Our Lives

by Daniel J. Levitin

The poet Dylan Thomas wrote that one should not go gently into that good night, that old age should burn and rage at close of day. As a younger man reading that poem, I saw futility in those words. I saw aging only as a failing: a failing of the body, of the mind, and even of the spirit. I saw my grandfather suffer aches and pains. Once agile and proudly self-sufficient, by his sixties he struggled to swing a hammer and was unable to read the label on a box of Triscuit crackers without his glasses. I listened as my grandmother forgot words, and I cried when eventually she forgot what year it was.

as I’ve grown older myself, and have spent more time with people who are in the last quarter of their lives, I’ve seen a different side of aging. My parents are now in their mideighties and are as engaged with life as they have ever been, immersed in social interactions, spiritual pursuits, hiking, and nature, and even starting new professional projects. They look old, but they feel like the same people they were fifty years ago, and this amazes them.

extraordinary compensatory mechanisms have kicked in—positive changes in mood and outlook, punctuated by the exceptional benefits of experience. Yes, older minds might process information more slowly than younger ones, but they can intuitively synthesize a lifetime of information and make smarter decisions based on decades of learning from their mistakes.

They’ve lived full lives and treat each new day as an opportunity for new experiences.

As a neuroscientist, I’ve wondered why some people seem to age better than others. Is it genetics, personality, socioeconomic status, or just plain dumb luck? What is going on in the brain that drives these changes? What can we do to stem the cognitive and physical slowdown that accompanies aging? Many people thrive well into their eighties and nineties, while others seem to retreat from life, prisoners of their own infirmities, socially isolated and unhappy. How much control do we have over our outcomes, and how much is predetermined?

offers choices we can make that will keep us mentally agile well into our eighties, nineties, and perhaps beyond. We need not stumble, stooped and passive, into that good night; we can live it up.

He has found that personalities can change: You can improve yourself at any stage of life, becoming more conscientious, agreeable, humble—any number of things. This is surprising, and it upends decades of casual speculation.

Learning how to avoid certain environments, habits, and stimuli that influence our personalities in negative ways is a crucial part of aging well.

the 1960s, when I grew up, many young people couldn’t wait to push old people out of the way. For all the tolerance, peace, and love that our Woodstock generation espoused, we were quick to try to sideline our parents’ generation. We chanted, “Don’t trust anyone over thirty,” and we might as well have chanted, “Don’t even pay attention to anyone over seventy.” Roger Daltrey of the Who summed up a pervasive sense of derision toward the elderly when he sang, “I hope I die before I get old.”

Aging, as it has been depicted in the media and our collective consciousness for centuries, implies both physical and emotional pain and, in many cases, social isolation. As the body became more frail, intellectual faculties weakened, and diminished vision and hearing prevented the elderly from engaging with their communities as they once did. Retirement spelled the end of life’s purpose and, sadly, seemed to accelerate the end of one’s life.

I want to draw out explicitly what happens in the brain when we feel rejected or underappreciated. Our bodies react to insults, both psychological and physical, by releasing cortisol, the stress hormone. Cortisol is very useful if you need to invoke the fight-or-flight response—say, when you’re confronted by an attacking tiger—but it is not so useful when you’re dealing with longer-term psychological challenges such as loss of respect. The cortisol-induced stress reaction reduces immune-system function, libido, and digestion.

the psychological stresses that can come from interpersonal conflicts, left unresolved, can leave us in a physiologically stressed state for months or years. In contrast, when we’re actively engaged and excited about life, our levels of mood-enhancing hormones such as serotonin and dopamine increase, and the production of NK (natural killer) and T cells (lymphocytes) also increases, strengthening our immune systems and cellular repair mechanisms.

Fast-forward twenty-five years. My own father, a businessman, was strongly encouraged to retire when he was sixty-two, to make way for someone younger. Like his father before him, he felt pushed out and began to question his self-worth. His social world shrank, he began to suffer physical ailments, and he became depressed. But by then, in 1995, the tide was already turning. Society and employers were awakening to the Eastern idea that the elderly may be not only of some value, but of superior value. My father put out feelers and was offered a job teaching a course at the USC Marshall School of Business. Soon he was teaching a full load of four courses per semester. That was twenty-five years ago. My father just signed a four-year renewal to teach until he’s eighty-nine. The students love him because he is able to pass on his real-world experience to them in a way that younger professors can’t. And by the way, that depression and those physical ailments were dramatically reduced once he found meaningful work.

Of course, finding ways to stay active and engaged is not always easy in old age, and it doesn’t completely compensate for biological decline. But new medical advances and positive lifestyle changes can help us to find enhanced fulfillment in life where previous generations may not have been able to do so.

I saw John two weeks before he passed at age ninety-two, and he was excitedly planning some new experiments he wanted to do. That’s the way to go out.

I’ve come to see a future in which we can plan ahead to fend off some of the adverse effects of aging; a future in which we can harness what we know about neuroplasticity to write our own next chapters the way we want them to come out;

You may have read that “old people” don’t need as much sleep as young people and can get by on four or five hours a night. This myth has recently been exposed by Matthew Walker at UC Berkeley. It’s not that we need less sleep as we get older—it’s that changes in the aging brain make it difficult for older adults to get the sleep they need. And the consequences are serious. Sleep deprivation in the aged is directly responsible for cognitive decline, not to mention increased risk of cancer and heart disease. Grandma didn’t forget where she put her glasses because she’s senile—it’s because she’s sleep-deprived. Walker has found evidence that sleep deprivation increases the risk of Alzheimer’s. Alzheimer’s disease (AD) is now the third leading cause of death in the United States.

for reasons we don’t yet understand, AD is selective with regard to sex. Sixty-five percent of patients are women, and a woman’s chances of getting AD now exceed her chances of getting breast cancer. Approximately two-thirds of the overall risk that you’ll get Alzheimer’s comes from your genes, with the remaining one-third associated with environmental factors such as whether or not you have a history of depression or head injuries.

On the biological side, a brain with Alzheimer’s is easily recognized by the shrinkage of the hippocampus—the seat of memory—and of the outer layers of the cerebral cortex (the part of the brain associated with complex thought and movements). You may have heard of amyloids, aggregates of proteins that have been found in the brains of Alzheimer’s patients. One particular protein, beta-amyloid, begins destroying synapses (connections between the brain’s neurons) before it clumps into plaques that cause the death of neurons themselves.

Fending off Alzheimer’s, he says, involves five key components: a diet rich in vegetables and good fats, oxygenating the blood through moderate exercise, brain training exercises, good sleep hygiene, and a regimen of supplements individually tailored to each person’s own needs, based on blood and genetic testing. The Bredesen Protocol is still in its early stages of validation—the

The protocol may or may not help, but at least the first four parts won’t cause any harm—we don’t know enough about the supplements—and to many it makes sense to start following these healthy lifestyle practices on the chance that they will end up being scientifically validated.

Prusiner won the Nobel Prize for discovering prions, proteins that can accumulate and cause neurogenerative diseases like Creutzfeldt-Jakob disease, a fatal condition that is characterized by memory loss and behavioral changes. Sound familiar? These are the markers of Alzheimer’s, of course, and Prusiner now believes that prions, because they can assemble into amyloid fibrils, are responsible for Alzheimer’s and Parkinson’s disease. At the cutting edge of this research is the idea of neuroinflammation as a precursor to Alzheimer’s, appearing long before clinical signs and symptoms.

the visible symptoms appear only during the actual destruction of brain regions—the cognitive effects we notice, such as memory loss and mood change, reflect relatively late stages of the underlying disease process. Depressive-like symptoms, such as loss of interest a...

chronic inflammatory process precedes the onset...

Current research is focused on whether anti-inflammatories (such as ibuprofen) can ease symptoms once they’ve arrived, or whether the drugs must be given before the onset of symptoms and thus act as a preventative (which is appearing to be the case).

Consider two friends who die at one hundred, both with identical life spans but very different disease spans. Grace begins a gradual health decline at fifty and by eighty requires twenty-four-hour care. Eloise begins to decline at seventy but the real health problems don’t kick in until ninety-five. All of us would prefer to have that extra twenty years of smooth sailing, followed by an extra fifteen years of happy life before disease limits our activities. I wrote this book on the premise that it is never too late to tilt the balance in our favor, to increase our health span by making important changes to how we approach aging.

I mentioned earlier that social stress can lead to a compromised immune system.

Parents living in poverty, suffering from mental illness, or facing great stress are much more likely to be fatigued, irritable, and anxious. “These states clearly compromise the interactions between parents and their children,” he says. And, subsequently, they compromise their children’s brain chemistry and resilience in the face of setbacks—even future ones.

“human brain development occurs within a socioeconomic context, and childhood socioeconomic status (SES) influences neural development—particularly of the systems that subserve language and executive function” (deciding what to do next and then doing it). Research has shown the importance of prenatal factors, parent-child interactions, and cognitive stimulation in the home environment in promoting healthy, lifelong neural development.

Early traumas can last a lifetime. They can be overcome with the right behavioral and pharmacological interventions, but it takes some work.

A third strand of Successful Aging, along with environmental influences and neural development, is that I’ve come to see old age as a unique period of growth, a life stage with its own distinct character, rather than a period of decline or a gradual turning down of the dials and knobs one by one.

we’re all familiar with: loss of vision, loss of hearing, aches and pains. What exactly happens when the brain and body age—what physiological changes affect our experience of ourselves and others? I’ll delve into these questions in this book, including brain cell atrophy, DNA sequence damage, compromised cellular repair functions, and neurochemical and hormonal changes.

Our digestive system experiences changes that, along with causing lactose intolerance, may make us gassier as we age. Our skin becomes drier. Our eyes become drier. Caffeine may affect us differently or stop providing its beneficial effects entirely. Processing refined sugar becomes more difficult as our pancreas ages.

The cost of sidelining the elderly is enormous in lost economic and artistic productivity, severed family connections, and diminished opportunities. We can begin to model better behavior by embracing those who are a generation ahead of us—our parents’ generation. And we can adopt practices that will keep us, as older beings, relevant and engaged with others well into our eighties and nineties . . . and perhaps beyond. I argue here for a very different vision of old age, one that sees our final decades as a period of blossoming, a resurgence of life that does not chase after our younger years, but instead embraces the gifts that time can bring.

What would it mean for all of us to think of the elderly as resource rather than burden and of aging as culmination rather than denouement? It would mean harnessing a human resource that is being wasted or, at best, underutilized.

It would promote stronger family bonds and stronger bonds of frie...

It would mean that important decisions at all scales, from personal matters to international agreements, would be informed by experience and reason, along with the perspective that old age bring...

Among the chemical changes we see in the aging brain are a tendency toward understanding, forgiveness, tolerance, and acceptance. While older adults may become more set in their ways, and there is a tendency toward conservatism, they can at the same time become more accepting of individua...

Older adults can bring a much-needed compassion to a world being rent by impatience, intole...

We have a silo problem in my field of cognitive neuroscience. There’s a tendency for researchers to talk to people in their own area, and not to talk across areas.

few people in one area talk to people in another, and so we’re left with a situation where neither medical professionals nor the public are able to leverage these advances for our individual and common good.

This led me to bridge two areas that have maintained separate intellectual traditions—developmental neuroscience and individual differences (personality) psychology. The more I study the intersection of these two, the more intrigued I am at how they can help us to understand the aging brain and the choices all of us can make to maximize our chances of living long, happy, and productive lives. The intersection of these two scientific fields, and how they apply to aging, is the core theme that runs throughout Successful Aging, and something that no one else has written about for a popular audience.

No matter what age we are, our brains are always changing in response to pressures from genes, culture, and opportunity. The choices we make dictate much of the lives we lead. But we are also affected by random things that happen to us, and the choices that others make. Opportunity, or lack thereof, is often a matter of luck, governed by large historical forces, such as wealth, plagues, access to clean water, education, and good laws. In ways both large and small your brain has been changed by your life’s experiences, whatever they are—by disappointment, love, interactions with key people, successes, illnesses, accidental injuries, pain, environmental toxins. In short, your brain is continually being changed by life itself.

traits—the ways in which we understand our individual differences—is

It traces its roots back to Aristotle, who explained differences in personalities among individuals as differences in their “matter.”

Franz Joseph Gall and the nineteenth-century scientist Sir Francis Galton launched the modern study of individual differences, with Gall even anticipating the modern neuroscientific idea that specific mental fu...

Individual differences psychology seeks to both characterize and quantify the thousands of ways that we humans differ from one another.

The goal of this work has always been to predict others’ future behaviors—if I know that you’re conscientious, for example, will I have a better chance of knowing how you’ll react to a certain situation than if I didn’t know that about you?

what can we do to maintain strength of body, mind, and spirit while coming to terms with the limitations that aging can bring? What can we learn from those who age joyously, remaining vital and engaged well into their eighties, nineties, and even beyond? How do we adapt our culture to service the needs of aging generations while also taking greater advantage of their wisdom, experience, and motivation to contribute to society?

Curiosity, Openness, Associations, Conscientiousness, and Healthy practices, what I call the COACH principle.