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

Date Reviewed
March 5th 2023

This book by neuroscientist/psychologist Daniel J. Levitin is encyclopaedic in detail, which may be useful in specific circumstances, but can be hard slow reading if you don't have that motivation.

However, I persevered at five to 10 pages at a sitting and don't regret being exposed to that detail. Not all of the heavy going had been reserved to the voluminous appendices

He starts the book with a pep talk and examples to motivate aging adults. Much of this focusses on biographical material of highly successful and prominent people. I can imagine it being helpful to some, but not needed by me.

Maybe the most important and optimistic message is that people have a lot of individual control over how well or successful they age.

And while the technical reading later was difficult, it gave me confirmation of the author's knowledge and focus on the subject. The author doesn't seem to be “talking down to the reader”.

For me, the start of the book was weak, but picked up as I continued.

And while only tangentially relevant to the topic, one of the most startling revelations came in the last paragraph or so of the book. “Two thirds of the people over sixty-five who have ever lived are alive today, and three quarters of the people over seventy-five who have ever lived are alive today.”

I can appreciate that lifespan has increased dramatically in the last century, but this historical reveal is still remarkable. I suppose birth and death dates are among the more carefully recorded. .

He has detailed chapters on sleep, diet, brain changes (both strengths and weakness) and socialization. There is less on exercise than I might have expected, since so far it is the only conclusively proven aspect that seems to retard mental decline. But what he does put in is interesting and different than I have seen in other books.

He creates an idea of a recipe to comprehensively address the key exercise elements of sound aging. It could be distilled to.... frequent walks/hikes on uneven terrain and varied surfaces in a forest with friends and relatives you enjoy spending time with.

On the exercise front, it gets the heart and lungs working and moving blood to areas of the body including the brain. Further uneven ground that must be compensated for requires alertness and brain activity. The friends and relatives provides the social interaction, which along with exercise, seem paramount in maintaining health. Doing it with the sights, sounds and smells of the forest world of our evolutionary development seems to bring a peace.

The author expresses his affinity for music both as an amateur practitioner and one who studies and appreciates the work of others. At one point, he praises both Joanie Mitchell and Stevie Wonder in the same context.

He also encourages people to continue to explore changing developments and technology in society even though it seems easier just to ignore it and leave it to younger generations.

Levitin talks about improving oneself as a senior by “becoming more conscientious, agreeable and humble”. He adds that it is a recent discovery that people can consciously change things about themselves, if motivated. Part of that may be avoiding environments, habits and stimuli that influence personality in negative ways.
This can reduce stress and promote happiness.

There is also more conclusive evidence that pattern recognition, learned through years of experience, can increase problem solving abilities as one ages.

Almost all physicians who write books on health make sure their profession remains quite central. Levitin pays some heed to this loyalty, but the book is primarily about what the person can do to advance their interests. He also doesn't give excessive credit to drugs and supplements.

He places some emphasis on a growing trend in explaining longevity. In past years, a lot was attributed to the genes inherited. Progressively it seems that environment and aspects within control are more important.

Although the brain only accounts for two per cent of bodyweight, its 85 billion cells consume 20 per cent of the energy.

To reinforce complexity of the brain, from birth more than a million connections per minute are added and that can rise to two million per minute at six months and each represents an experience, a memory or a perception. Synchronized firing in tandem is the essence of thought, learning, memory and experience. There are more connections in the human brain than particles in the universe. Activities often involve the contribution of many varied cells to produce what seems a fairly simple act.

 

 

 

Precis

 

“Sleep deprivation in the aged is directly responsible for decline in cognitive skills and risk of cancer and heart disease as well as Alzheimer's” is a statement in the introduction that should catch people's attention.

Fending the latter off seems to have lifestyle components...a diet rich in vegetables and good fats, oxygenating the blood through moderate exercise, brain training exercises, sleep hygiene, supplements tailored to personal needs based on blood and genetic tests.

He says how we raise our children may have a greater impact on the last years of life than previously imagined.

Your life, notably your brain, is formed and changed by opportunities you have from beginning to end and many of these are random. And one interesting statement “the age that come up most often as the happiest time of one's life is eighty-two” (they may have perspective, but also waning memory). And if you know what to look for you can tell whether a five-year-old will be a successful eighty-five-year-old. It seems that patterns of behaviour laid down in childhood, with biological effects, endure into adulthood.

However, at the same time, things can be changed with concerted effort. And it seems life circumstances and our responses to them have more bearing than personality traits. Genes only provide a basic outline. Culture is a large factor. And opportunity or the situations we encounter the other. Some of these opportunities are determined by the way others see and treat us.

Optimism, tempered by conscientiousness, increases longevity, if it is not so extreme to cause a person to ignore health warning signs.

Testing oneself and trying to get better, and that includes taking up new activities or enterprises,(despite advancing age) is a theme that runs through the lives of inspirational people.

Levitin writes about intelligence quotient (IQ) and the more recently recognized emotional intelligence (EQ), but in predicting life success maybe more important is curiosity quotient (CQ).

He speaks of the value of optimism and projecting positiveness, even if not feeling it. Such openness can lead to genuine optimism.

And there seems to be a high correlation between compassion (not judging people too strictly in case you are wrong) leading to happiness. The author cites the Dalai Lama, whom he has met with several times, in this context.

He condenses the five key items curiosity, openness, associations (sociable), conscientiousness and healthy practices into the acronym COACH.

And an explanation for those who wonder why they can't remember the reason they went somewhere in their own house. After the age of forty a neurological turn inward has brains spending more time contemplating its own thoughts versus taking in new information from the environment. And reassuringly, this is a normal trajectory of an aging brain.

Memory and the fear of loosing it is understandable as it is our identity........ who we are and what we think. It is the narrative of our life from the past and going forward.

And memory, as it is stored, is facts along with 'creative guesses” added by our brains. As time goes by, we tend to attach more accuracy to what we remember than it warrants.

Our brains abstract out irregularities and retain the general. This generalization allows us to adapt to situations and things that are different, but similar.

Maybe surprisingly as we age we get better at pattern matching and this can manifest as wisdom often leading to increased problem solving skills and a better prediction of what will happen next. Age often increases big picture through stronger generalizations and abstraction while loosing the quicker calculations and memory of youth. Too much memory can limit abstract and generalization.

Total recall is not the bonanza for many situations that people imagine it is. Excessive detail memory is often correlated with autism.

Levitin goes on to explain “explicit” memory as your conscious recollections and “implicit” memory as things you know without being aware of them. And then there is “semantic” memory for general knowledge and “episodic” memory for specific often autobiographical events in your life. These different types of memory are stored in different parts of the brain.

Alzheimers disease seems to attack the hippocampus and the medial temporal lobe both crucial in “explicit memory”, where they retain such “implicit” skills as using a fork, reading, working the television set. In essence there are “several memory systems” and they can all be disrupted as some other task or idea intrudes. In addition, these systems are in different areas of the brain and often require co-ordination between them.

Procedural memory (implicit) is a series of tasks that go together to make up a skill. Autobiographical memory is the system closely associated with sense of self ...what you like and what you can do. It is prone to huge distortion (making things up) often in aid of maintaining consistency of thought and belief. Often coupled with that is a belief that these memories are accurate.

The multiple-trace theory (MTT) postulates that the more repetitions there are the more unique traces of this event there are, increasing the likelihood of accurate and rapid recall. And this is essentially the process for learning. While not universally accepted in the field, MTT suggests why we forget more recent than older events.

New memories can be enhanced by repeating immediately after, drawing the memory or writing down.

Differences in the prefrontal cortex are prominent between adults, pre-adults and other primates. Essentially the difference manifests as inhibition causing adults to more likely resist behaviour that could prove dangerous or unwise.

Distractibility can be a sign that this part of the brain may be shrinking also compromising memory.

Ironically testing older adults brains can bring on the four stressors that most inhibit memory. People are usually the best on these kinds of tests shortly after waking up. For older adults that is often earlier than for younger people. Under ideal conditions the older may perform as well as the younger.

Synchronized firing in tandem is the essence of thought, learning, memory and experience.

Two jobs of the brain are to explore the world and create neural circuits incorporating that understanding. A third major job reaches its peak in old age: prediction, through searching patterns and ideas.

In the early years, an excess of neural connections are made and for more than two decades from about two the brain dismantles the unneeded connections. It is to create efficiencies and specialties to respond automatically to the environment and the tasks needed.

Most adults lose five per cent of brain volume per decade after 35 and it speeds up after 70 leading to slowing of cognitive function. The prefrontal cortex and the hippocampus suffer most from shrinkage. The prefrontal cortex is responsible for setting goals, planning and impulse control. Difficulty keeping track of thoughts is one symptom in aging. The hippocampus is responsible from memory storage and retrieval.

Myelin, the insulator around nerves, declines leading to reduction in efficient conductivity. Dietary fats (fish) is a good source in ameliorating this.

The executive mode of the brain is engaged when thoughts are directed and distractions filtered out. The daydream mode is resting from concentration and that is often when the solution to a problem you have been seeking “comes to you”.

Brain plasticity or the rewiring of brains is possible even as people age, but is sometimes slowed down. This can involve complex learning as well as more simple adaptation to change.

Learning a manual skill when you are young and keeping it up as you age is brain protective as is learning a new skill.

Senses, such as hearing and vision are often lost earlier than other faculties.

“Perception doesn't just happen__it entails a string of logical inferences and is the outcome of unconscious inference, problem solving, and outright guesses about the structure of the physical world.”

Perceptual completion, a compensation for failing senses, gets better with age because there is a larger data base of observations to draw from. Categorization with age becomes more prevalent as an efficiency.

Declining of close vision is one of the most reliable markers of aging, often beginning around 40.

Cataracts, another vision problem with aging, is best countered by wearing sunglasses from a young age.

Hearing loss is more isolating than vision loss.

The author recites the dangers accompanying the loss of each of the senses. Enjoying tasty foods becomes one of the last sensory gratifications, but also declines.

Keeping senses stimulated is critical to keeping the brain active and one of the best ways to do that is to go or be taken outdoors. Augmenting this is complex physical activity which may be walking on uneven surfaces.

“More intelligence should mean we are more likely to solve new problems.” This often involves making associations between information both old and new and seeing how it interacts with other information. In older adults, it may take the form of associations, experience, pattern recognition and use of analogies to predict future outcomes.

Levitin 'does a job' on IQ and the narrowness of it as a measure of intelligence and how it has been used to discriminate with little attention to other, often more crucial factors relating to performance in school related activities presumed to correlate with intelligence.

He describes “crystallized intelligence” as things you have already learned, “fluid intelligence” as the potential to learn and apply and a third one “acquisitional intelligence” the speed and ease of learning.

“High fluid intelligence is protective against the declines of aging, not just intellectual but emotional ones as well.”

In the chapter, he refers to 10 different kinds of intelligence and reports that great strength in one may be accompanied by proportional voids in others.

IQ correlates moderately with school grades, that is about 25 per cent.

The ability to learn things quickly reaches a peak in adolescence and the college years and declines after age 40. Fluid intelligence, the ability to use what we know, is lower before 40 and picks up each decade after.

Cognitive reserve can insulate against damaging effect of aging. That reserve is increased with high education, high fluid intelligence and a balanced diet.

Stress is “the psychological tension we feel from anticipating adverse events, and the biological correlates of them.” Stress and the degree of it varies from person to person and with different causes, but it effects longevity. While the hormones associated with stress cause damage, in other circumstances they may save one's life.

Stress can be reduced through several different activities. He brings up the term “allostatic load” which describes the cumulative effects of stress and your body's response to that stress.

Insomnia, he says, is a hallmark of aging and often can be a symptom of depression. Effecting 25 per cent of men and 40 per cent of women. Some neural and physiological systems do not function normally.

Blood flow to the brain can decrease with age and may simply be a reduction in exercise.

And a revelation that may arouse mixed emotions.”Most people in monogamous relationships show lower levels of testosterone than those not in committed relationships. In addition high testosterone in both genders can lead to riskier behaviour.

While some declines in estrogen and testosterone seem obvious along with those are losses in cognitive functioning, memory, motivation and mood, immune system function and bone density. This can be reason to have the levels checked and possibly augmented.

Protection against cognitive decline and physical illness can come from maintaining the activities you have been engaged in.

Levitin points out how many feelings are determined, not so much by outside influences and choices, but by chemical changes inside. Loss of dopamine can decrease the motivation to seek novelty and learn new things.

“The hippocampal volume reductions which make it harder to store new memories and easier to retrieve old ones, and you have a formula for conservatism.”

“People with a fixed mindset generally have an external locus of control. They are low in curiosity and openness. They aren't interested in learning new things and don't think the payoff of learning new things will be worth the effort.”

Where those with an internal locus of control believe they can change their skill set and continue to learn.

With age comes an increase in intrinsic rather than extrinsic motivation so that external rewards are less satisfying.

Loneliness is associated with early mortality and indicated in almost every medical problem and doubles the likelihood of Alzheimer's. It may be worse than smoking 15 cigarettes a day. Loneliness is subjective and it is relatively modern problem and evidenced by the decline of many social/political/religious organizations. Once the chemical level drops social isolation and loneliness increases marked by a decline in glutamate important in transmission of signals throughout the brain. Symptoms can include fearfulness and aggression.

Levitin expresses considerable skepticism that drugs work better than talk therapy, which often takes longer.

Religious people seem happier than non religious. The reasons may include social network, sense of purpose and meaning, However, religious people not part of a community don't seem as happy.

He points out that younger adults try to make their environment suit them, while older adults try to suit their environment.

Older adults seem happier when they are not stripped of all decisions and control about themselves and their care.

Some people decline physically and mentally when they stop working so it is advised that one doesn't, if they don't have to. Healthy relationships and meaningful work, says Levitin, are the two most important things in life. Volunteerism can fill the role of paid work. Complexity in work, including making decisions, interacting with people and learning new things protects people from decline.

He points out that medical science focusses on life span rather than disease span. And the latter relates to pain, often chronic pain.

Chronic pain effectively adds six years to one's age. This pain increases in 50s and 60s and declines in 70s and older.

That pain is in your head is true, but that you are imagining it, not necessarily.

Pain leads to protecting the injured part which leads to survival. However, an evolutionary advantage of chronic pain, where nothing can be done, has not been determined.

Pain is influenced by cultural, environmental, historical and cognitive factors. It is also influenced by psychological factors.

And of curiosity, the red hair gene is associated with the gene to feel pain.

Pain is diminished when people have activities that distract them. Changing mood can also change distraction of pain.

He points out that a drug that beats the placebo by 15 per cent is doing a decent job, at least for some people.

Physicians may keep on adding drugs to a patient for fear that they might be blamed for consequences that can be attributed to that drug. But that pattern of poly-pharmacy can lead to negative drug interactions. Prescribed, as well as, over-the-counter self medication can lead to adverse interaction.

Levitin also discusses the impact on aging of one's internal clock regulating circadian rhythm.

Cataract surgery, allowing more blue light in during the day, may restore sleep patterns.

Not only when and how much you sleep is important to rhythm, but also when you eat and exercise contributes, especially with older people and can lead to or address health issues.

And there are individual rhythms dictating when, during the day, a person is functioning their best.

Being forced into a shift that doesn't suit your normal rhythm can lead to accidents, depression and reduced productivity. Artificial light and video screens have contributed to upsetting the million year circadian rhythm with progressively more people going to sleep after midnight, but still trying to get up early in the morning.

With aging, the rhythm seems generally advanced to earlier to sleep, earlier to rise.

Deterioration of insulating myelin sheath around nerves and a decrease in neurochemicals and hormones reduces the operation of the circadian rhythm. And there are suggestions that this may reduce longevity.

Sleep hygiene involves avoiding bright lights before bed, sleep in the dark and maintain a regular schedule. Some exercise late in the afternoon may also help. Certain activities have peaks at different times of the day.

Sports selected may also depend on whether one is a morning or afternoon/evening person.

Food is an obsession for many as they age and nutrient absorption becomes less efficient. Dietary research is hampered by a lack of controlled experiments and the issue that individuals are different and respond to food differently. As such “diets” often work for a small proportion of people trying them under the implication that their characteristics produce universal effects. And some are advocated with little or no scientific support or individual appropriateness.

Antioxidants, a popular virtuous food, suffers from lack of rigorous scientific support that it works. Several of the popular vitamin supplements also suffer from lack of convincing evidence that they work as suggested. And the epithet that “it can't hurt” is also not true. Some may interfere with others. For example it has been shown that vitamin C and E can block the health promoting effects of exercise.

Levitin says that statins do reduce the likelihood of a heart attack, but by an extremely small amount. Similarly consuming saturated fats seems to have less impact than previously thought.

On the other hand, soluble fibre can capture and remove LDL (bad cholesterol). Whole grains, soya beans and fruit can provide this component. While saturated fats don't have much to do with causing heart attacks omega fatty acids from nuts, extra virgin olive oil and oily fish can prevent them (supplements don't seem to work).It seems that the food provides the optimal concentration of key elements. Supplements may actually be negative. Bodies have complicated and multiple interacting factors.

Caloric restriction such as fasting and vigorous exercise appears to be good for the brain. It is related to complex alteration of neurochemical concentrations.

Increasing longevity and the detrimental effects of aging appears to be just eating less. The optimal amount of fasting is not known, but people can increase the amount by practice. You may wish to start it in consultation with your physician.

Again consuming olive oil comes up along with cruciferous vegetables. The traditional Mediterranean diet seems to provide a lot of the key elements.

With age goes a decreasing efficiency in processing food and getting the right amounts of nutrients.

He doesn't provide good news for vegans when it comes to protein. Leucine, one of the nine essential amino acids is mainly found in animal proteins. He advises dairy sources, beef, tuna, chicken, peanuts soybeans and eggs.

Dehydration is a particular enemy of people over 70. A decline in thirst detectors can be part of the problem.

Probiotics such as found in kefir and yoghurt seems to improve mood. And while dosing with prepared probiotics may help it is best in conjunction with food.

The microbiome, the collection of bacteria in the digestive tract, is kept healthy by association with different people and animals and this in turn increases overall health.

The area of the brain most stimulated by exercise is the hippocampus, critical in memory formation. As such exercise enhances memory. And for those with mild cognitive impairment exercise has a significant beneficial effect on memory. While many things help the “single most important correlate of vibrant mental and physical health is physical activity.”

Deterioration of nerve transmission speed leads first to loss of dexterity and then hand eye co-ordination. Sarcopenia, the loss of muscle mass, can be reversed with training.

What allows people to stay “young” despite advancing years is “synaptic plasticity”, the ability of the brain to make and form new connections. This requires a dramatic increase in the amount of energy used by the brain through brain cells called astrocytes. “A mounting body of evidence shows that physical activity increases the effectiveness of astrocytes and thereby enhances synaptic plasticity, memory and overall cognition.

To convince sedentary people to take up exercise the advocate often consoles them on how little is needed to make gains. For reducing the time devoted he advocates Hight Intensity Interval Training (HIIT). It involves rapidly going from one exercise to another for 10 minutes. “While anything helps, a bit more is probably better.”

This seems to yield the same health benefits as long term aerobic exercise. The majority of resistant exercisers find HIIT more enjoyable.

The author puts the increasing level of sleep loss on the list of the four greatest threats. Less than half of one per cent can get along with less than five hours. Nevertheless humans deliberately deprive themselves. Sleep is the time for cellular repair. The hippocampus and thalamus are most effected by sleep deprivation.

About 40 per cent of people over 65 have sleep problems, but need remains the same. While naps can compensate to a degree, they should be limited to 20 minutes. Over 65 a change in schedule such as staying up an extra hour can effect memory, alertness and the immune system for days. If you stay up an hour later don't try to rectify it by sleeping in an hour longer. It is better to get up at the regular time, hence maintaining part of the schedule.

There may not be a limit to human longevity if diseases that afflict people between 80 and 104 can be found. Gene mutations that extend longevity also postpone age related diseases.

Human cells normally replicate 50 to 60 times over the course of a life. With each division the telomere at the end of the chromosome gets shorter. When they become too short cell division, repair and renewal stop.

The characteristic of conscientiousness...the propensity to be planful, reliable, industrious, adhere to social norms and delay gratification ...in childhood, predicts telomere length. Exercise (remediates the effects of stress) and eating whole foods are also correlated with telomere length and remediates the effects of stress. A deleterious community with poor social cohesion also shortens telomeres.

Short term manageable stress also strengthens cells where long term chronic stress shortens telomeres.

He says that if cancer were eradicated it would only extend lifespans by seven years.

Extending life beyond most common diseases would involve therapies at the cellular level where the aging process might be reversed. But the idea doesn't gain much traction in the scientific community.

And a good quote “For every complex problem there is a simple solution and it is wrong.” Those in science, but not journalists or the public, know that most therapeutic ideas come to nothing and even then the development time may be in decades not years.

Eighty year-olds now live four years longer than they did in 1990 and centenarians live longer past 100. More eighty year-olds continue making contributions and 60 year-olds are doing things that 40 yearolds used to. It is the health span that is dramatically expanding.

That exercise and spending time with others improves the brain, there is little evidence that games for brain training does much, except improve the skills for the game.

For all the evils, nicotine, or at least smoking, were visiting on us, its characteristics are now making it seem a drug to treat Parkinson's and Alzheimer's. But it still has deleterious effects. The author uses it as an example of how a drug can be beneficial to some systems while wreaking havoc on others.

He suggests that meditation might decrease some negative health effects, including Alzheimer's.

Levitin is saying that we are moving into an age where we have some control over aging.

As a group, older adults are happier than younger. Happiness declines from the late 30s and increases again after about 55. It may be that ambitions, expectations and plans of the 20s and 30s do not turn out as well as hoped. Older adults have a positivity bias putting a better spin on their lives and optimism going forward. Perceived quality of life is more important than objective.

Culturally the individualistic societies of Europe and North America focus highly on themselves and maximizing the amount of good stuff they have. The collectivist and holistic societies place more emphasis on context and less on personal advantage and may put an acceptable limit on it.

And a gem that could spur discussion from a Harvard study “the most conservative men ceased sexual relations at an average age of sixty-eight, while the most liberal men had active sex lives into their eighties”. And another that might provoke some resistance ”most people in monogamous relationships show lower levels of testosterone than those not in committed relationships. (and here I thought it was virtue-based, not a chemical). From an evolutionary basis people in a committed relationship stayed together and parenting and these characteristics may be modelled by their children. Until fairly recently the difficulty of divorce seemed premised on the idea of keeping families together through thick and thin, or violence.

Staying active with meaningful pursuits and activities in later years correlates with happiness.

In the work world, multi-generational teams tend to be more productive than homogenous groups.

Near the end of the book he highlights three major factors that determine how well we age. First childhood experiences, parental attachment and head injury (concussion and dementia) cannot be controlled for the aging person, but they may help children they influence.

And social interaction is a complex process, which exercises the brain.

Other additional contributions include jettisoning grievances and grudges.