Read Live Long, Die Short Online
Authors: Roger Landry
When Dr. Jill Bolte Taylor was thirty-seven and a neuroanatomist at Harvard, she had a stroke that left her unable to speak, walk, or do much of anything she had done before as an intellectual. She describes her remarkable journey in her book
My Stroke of Insight
.
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Her story is compelling on many levels, but what is particularly astonishing for all of us is that after eight years, she was fully recovered. After a long road of rehabilitation and dogged determination, she walks, writes, and speaks publicly about her experiences. Of course, her catastrophic cerebral hemorrhage wiped out part of her brain, destroying many of her pathways. But, determined to regain what she lost, she has clearly built new roads, either by finding other routes to her goal and building those up, or perhaps, even by making new ones. By a process called axonal extension, neurons are able to grow connections to other brain cells to create a pathway. Other neuron appendages, called dendrites, which bring signals into the neuron, are also able to grow and create or enlarge new pathways.
And Jill Bolte Taylor’s story, despite its dramatic outcome, is not an outlier. Returning soldiers from Iraq and Afghanistan with devastating brain injury have shown a remarkable ability to recover. The ABC television journalist Bob Woodruff, injured by a roadside bomb in Iraq, is a well-known example of these new possibilities.
When I was in medical school, the prevailing belief was that once we were physically at maturity, we no longer made new brain tissue. After our brains were fully formed, aging and all the situations associated with aging (i.e., head trauma, hypoxia, heart attacks) gradually depleted the neurons in our brain, causing the brain to atrophy until we succumbed to senile dementia. That’s what we all believed just a few decades ago. And, fortunately, we were wrong.
What we have now that we didn’t have then is the ability to scan functioning brains, to look at brains as they are working! This has given us remarkable ability to better understand brain function, response to challenge, and reaction to specific tasking, as well as anatomical information that we can now correlate with function. And what we’ve discovered is
remarkable indeed, a very optimistic picture of what’s possible and of our role in making those possibilities a reality.
First of all, “use it or lose it” applies to the brain function as well as to the body. When we use the skills and knowledge we have, the pathways, the many connections within the brain, like the roads we spoke of earlier, remain functional and in the best shape they can be. Don’t use them, and they become more difficult to use if not completely unusable. In fact, by a process called synaptic pruning, the connections making up the unused pathway atrophy—basically go away. Areas of the brain can atrophy when the functions they are responsible for are no longer or rarely used. In fact, atrophy of the brain is a common observation with aging, but what used to be an accepted part of getting older is now in question. Is the atrophy of aging merely the result of lack of use? The answer seems to be, for the most part, a resounding
yes
! So, if we continue doing those crossword puzzles, playing that guitar, speaking a second language, making that furniture, or cooking our favorite pasta, we continue to do it well. This equates to basic maintenance of our brain function and essentially involves staying engaged with things we have always done.
But there’s more good news. It’s clear that, under certain conditions, not only is the brain able to make new connections by means of extending connections with the parts of the cells called axons and dendrites, but the brain is also able to make
new cells
! This is indeed much more optimistic information than we learned in medical school. Neurogenesis, the ability to make new neurons, is well documented in the mammalian brain and can persist well into old age. The solid evidence for new cell generation is currently limited to areas of the brain important for making new memory and converting that short-term memory to long-term memory, as well as the areas important for spatial navigation, the ability to get from one place to another. Within the memory area, the hippocampus, however, it appears that although new cells appear, not all survive, and that stress and depression decrease neurogenesis. The hippocampus, in fact, is one of the first areas affected by Alzheimer’s, bringing into question the role of depression and stress in the development of the disease. There is growing evidence for neurogenesis occurring in other areas of the brain, such as the cerebellum, responsible for movement coordination. Recent research has linked meditation to more gray matter and to less age-related atrophy of the brain.
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Brain scans can tell us what is happening as the brain works. People learning new skills, such as a language, show activity and, over time, growth in areas of the brain where these skills reside. Brains get larger in areas
housing the new skill. It appears that we are indeed the architects of our own brain. Challenge it, and it will respond.
What is the significance of brain growth? First, it tells us that the brain is alterable, and not some static organ that is gradually declining. Second, this ability to grow—this neuroplasticity and neurogenesis—allows us to learn new things no matter what our age. Third, although there is not yet clear evidence that we can prevent or cure Alzheimer’s, there is a growing body of evidence that suggests we can influence our risk of developing symptoms of this dreaded disease. How? You guessed it. Lifestyle.
A long-term study in Minnesota involved tracking the lifestyles and mental decline in a group of nuns.
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When they died, autopsies showed some with Alzheimer’s brains; there were tangles of neurons, and the plaques of beta amyloid material surrounded many neurons. Yet, prior to their death, these nuns had experienced no symptoms of Alzheimer’s. No significant memory loss, no agitation or withdrawal. Basically, the brain pathology was a surprise to all and warranted a theory of explanation. The investigators concluded that a lifestyle of regular physical and mental activity protected the individual from the onset of symptoms even when the disease was present anatomically. These intriguing conclusions have been validated by subsequent research and are the basis for new approaches to brain health. In fact, two recent studies reported that dementia rates in Britain and Denmark have dramatically declined over the last two decades—observations attributed by the researchers to better healthcare and changing social factors such as education.
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In fact, neuroplasticity, neurogenesis, and the potential for preventing dementia make up an extremely active field of research, media stories, and a wave of new products claiming brain health as an outcome. So, with the overpowering amount of claims and products out there, what is fact and what, if anything, can we do to make it more likely we will not fall victim to dementia?
What we do know is that the brain is a dynamic organ and can remain that way even as we age. We know that we can continue to learn as long as we
have a pulse. Clear also, thanks to brain imaging, is that the brain has the ability to respond to environment, behavior, and even disease and devastating injury. This knowledge of the brain’s ability to rewire itself and make new cells—in other words, of neuroplasticity and neurogenesis—has rewritten the books on what is possible as we age. Lowering the likelihood of falling victim to declining cognitive function, however, requires that we once again act as warriors against the threats to our mental function: cardiovascular disease, stress, cognitive laziness, and injury. Fortunately, these threats can all be dramatically reduced by how we choose to live our lives, by our lifestyle, by the choices we make every day. You do have a say in how well your brain will age. So, what is that lifestyle?
Once again, it’s clear that we must pay attention to all aspects of our life in order for our brain to function at its best and remain healthy longer. The Ten Tips in this section, in fact, all relate to our brain as well as to the rest of our body. We are one organism, and although science and medicine have fractionated us into neurologic, cardiovascular, gastrointestinal, and a multiplicity of systems, in order to deal with the vast amount of information known about each, we move through life, get sick or stay healthy, and eventually die as one organism. All aspects of us relate and interact with each other. One affects the other, whether positively or negatively, and so we ignore aspects of our whole self—our core, authentic, species-driven self—only at great peril. So, knowing this, we are not surprised to hear what lifestyle qualities are associated with a better cognitive aging experience. Dr. Rob Winningham, a colleague of mine from Western Oregon University, authored a book called
Train Your Brain: How to Maximize Memory Ability in Older Adults.
This book is one of the more comprehensive and well-researched books on the topic, and strongly advocates lifestyle as an effective approach to continued brain fitness.
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Dr. Winningham is not alone in his focus on lifestyle. Brain-fitness experts agree on which lifestyle characteristics deliver the goods when it comes to cognitive function:
And so it’s once again clear. The road to excellent brain health is pretty much the road to overall health, and that road is a lifestyle that pays attention to our physical, spiritual, and social health as well as the intellectual. It’s not a difficult concept; it’s not as difficult as you might think. There are undoubtedly people in your life who are doing it. Take Nola, for example.
Nola is a celebrity of sorts in the world of successful aging. She will tell you she was born in 1911, but she says, “I don’t keep track of my age.” Widespread recognition came when she earned her college degree at age ninety-five. That was, in fact, a world record, but she went even further, earning her master’s degree at age ninety-eight.
Nola raised four sons with her husband, Vernon, on a family farm. When her husband died in 1972, she began taking college courses. When she was within thirty credits of completing her degree, she moved a hundred miles to a university apartment to finish alongside Alexandra, one of her thirteen grandchildren. Governor Kathleen Sebelius of Kansas presented the degree to her, an event that was followed by appearances on
The Early Show
, MSNBC, CBS News, and
The Tonight Show with Jay Leno.
After her undergraduate diploma ceremony, Nola fulfilled a dream of being a storyteller on a cruise ship when she took a job as a guest lecturer for a nine-day Caribbean cruise. And of course, Alexandra went also. Before pursuing her master’s, she of course took time to help with the family wheat harvest.