The Aging Human Brain
As we age, many of us increasingly feel our memories are declining. We cannot remember where we left the car keys — and we joke somewhat defensively about having senior moments.
For example, a friend of mine has a very attentive pet dog. It follows him everywhere. My friend tells me he’s gotten up from his chair in the living room more than once and headed for the kitchen—his dog trotting eagerly behind him. When they reach the kitchen, the dog and my friend stare at each other excitedly. But neither one knows the purpose of their journey.
Kidding aside, much of what mainstream science thought was true about human brain function at the beginning of this century has since been proven wrong or found to be incomplete.
For example, we now realize that memory loss and brain atrophy are not inevitable. Mainstream science used to claim that the brain was largely constant, with a fixed number of brain cells (neurons). They also claimed that throughout one’s life, neurons die off, neural networks diminish, and things like memory and thought-processing speed take a hit.
Because of this misinformation, most people have no idea how to keep their brains healthy as they age, or even that it is possible. They believe their fate is set in concrete in their DNA, and nothing can change it.
People think that because the brain is encased in a hard shell of bone, it is a locked box — unchanging, impenetrable, indecipherable, and unable to be changed or improved.
But as science has come to understand how flexible and dynamic the human brain is, the certainty of brain cell loss no longer holds up. A healthy brain can keep serving you as you age if you stay alert.
Latest research suggests that by using your brain, you can stay aware of the thoughts and feelings it processes every minute. You can also choose to maintain an upward learning curve no matter how old you are.
By doing so, you create new brain structures (neurons, dendrites, synapses, and neural pathways) that improve brain health and may even help stave off Alzheimer’s disease.
Losing the neurons
The healthy human brain loses about 85,000 neurons per day or about one per second. At this rate, it would take more than six hundred years to lose half of the neurons in your brain! But this is a tiny fraction (0.0002%) of the roughly 40 billion neurons in your cerebral cortex.
At age twenty, the total number of nerve cells in your brain doesn’t change much by age seventy. By choosing ‘healthy brain’ activities every day, such as physical exercise and learning new things, you can actually increase the number of new nerve cells. At the same time, you promote the survival of these new cells and connections.
The growth of new neurons is called neurogenesis. In contrast, emotional stress and trauma can lead to increased glucocorticoids in the brain, which are toxins that inhibit neurogenesis.
Alzheimer’s disease (AD) is one of the dreaded diseases of aging today. It starts with a preclinical phase in which AD neuropathology begins to accumulate, but cognitive performance remains normal.
A disease like Alzheimer’s can take decades before memory, thinking, and behavior are affected. Currently, about 47 million Americans have some evidence of preclinical AD.
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Now that biomarkers for AD have become available, it’s possible to identify preclinical AD in cognitively normal individuals. With such early detection, the preclinical period can be used to optimize brain function by strengthening neural networks and stimulating new neuron growth—all of which contribute to a healthier brain.
How to achieve and maintain a healthy brain
Research shows that significant ‘healthy brain’ gains emerge when individuals engage in regular aerobic exercise for 50 minutes three times a week. Exercise improves cerebral blood flow, which supports memory and other brain functions even after you finish your workout.
When it comes to brain health, exercise isn’t necessarily the solution, but inactivity is definitely the problem. Countless studies show the brain prefers a body in motion, and it takes little to reap enormous benefits. So, every time you are about to sit, ask yourself, “Should I be moving instead?”
Restorative sleep is another necessary ingredient for a healthy brain. Adequate sleep and physical exercise help prevent age-related brain diseases. They are unrivaled treatments we can’t get elsewhere or in other ways. Sleep consolidates memory, while physical activity releases substances that nourish brain cells and promote their growth and survival.
Giving your brain time to process new information also seems helpful. Small mental timeouts can assist recall. Even a few seconds of idle time—meaning time when your brain isn’t confronted with new or stimulating information—may be enough to strengthen your memory of what you’ve just encountered.
It is also important to avoid cruising on autopilot. Life moves fast, and we often compensate by falling into routine and taking the path of least resistance. We let our activities, thoughts, and conversations become overly lazy or inactive.
Meanwhile, novelty and inspired thinking strengthen your memory and overall brain health. Breaking from typical routines and challenging yourself with change is an excellent way to keep your mind-brain connection from stagnating.
As we age, the bottom line is that key brain areas involved in memory and learning can keep producing new nerve cells and neural pathways. Restorative sleep, physical exercise, social connectedness, and mentally stimulating activities (like reading this article) greatly support this process.
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If you found this article ‘thought-provoking’ and stimulated your ‘aging brain,’ you might enjoy two of my books from my series of Brief Books. Their titles:
- “Congratulations! You’ve Reached the Winter of Your Life — So, What Now?”
- “70 and Beyond”
Why ‘Brief Books’? Well, today we live in a fast-paced world full of distractions. As a result, our attention is fragmented. And so, asking today’s reader to commit to a 400-page tome is a tall order.
Those who enjoy reading typically don’t have 10 hours to absorb a dense, slow-build message. They want clarity. They want insight. They want it brief, and they want it now.
So, I have developed a series of ‘Brief Books’ that offer an updated, ever-expanding retelling of my ‘knowings,’ originally published as a series of six books on Amazon in 2022.
My new series of Brief Books — which can be found on Amazon under “Books by Stephen Geist,” — is intended to deliver valuable content for readers looking for ‘quick read’ wisdom on specific topics that interest them.
Each of my Brief Books relates to the others, but you don’t need to read them in any particular order. By reading any or all of my Brief Books, you may awaken to a new state of ‘being,’ as I have—one that is both breathtaking and enlightening.
