David Wright wrote this autobiography about the influence of deafness from the time that he became deaf until he graduated from college. He was born in South Africa in 1920 and became totally deaf in 1927 due to scarlet fever. He states that he was fortunate in many ways. At seven, he was old enough to have learned to speak and to read, but he was still young enough to focus on mastering his disability and not become a victim. Continue reading
Vanessa Potter experienced a brain injury from a sudden inflammatory response triggered by a rare autoimmune disease. Within two days she went completely blind and lost much of her feeling and motor skills. She regained her sensation and motor abilities and partially regained her sight during an extended period of recovery. Continue reading
If you have any question about the influence of how we evolved on our health, I hope that the following information from The Story of the Human Body by Daniel E. Lieberman convinces you….
My notes from reading this book are long due to the importance of the topic and the quality of the book.
It was once said that the study of genetics taught us just how important the environment is.
In this book, I use the term “adolescence” to refer to the period of from ten until twenty-five.
The United States lags far behind the rest of the developed world on most indices of adolescent achievement and health.
New research shows that the brain continues to mature well into one’s twenties.
In general, the earlier age at which children now mature physically is much more worrisome than most people recognize, because it doesn’t bode well for physical or mental health – earlier puberty places people at significantly greater risk for a host of physical, mental, and behavioral problems, including depression, delinquency, and even cancer.
The fact that the adolescent brain is malleable is both good and bad news, though. As neuroscientists are fond of saying, plasticity cuts both ways. By this they mean that the brain’s malleability makes adolescence a period of tremendous opportunity – and great risk.
The United States spends more per student on secondary and postsecondary education than almost any other country in the world, so it’s unlikely that our mediocre school achievement or worrisome college attrition is due to a lack of financial resources.
And as the world’s leader in prison population, we spend nearly $6 billion each year incarcerating adolescents, many of whom have committed nonviolent crimes and who could be managed in the community at a fraction of the cost.
One-third of students who enroll in college never graduate; the United States has one of the lowest college-graduation rates in the industrialized world, despite the fact that the economic returns on college completion in America are among the world’s highest.
The birth rate among unmarried women increased by 80 percent between 1980 and 2007. In 2011, nearly one-third of the women who gave birth had never been married. Having a child outside of marriage increases the risk of young women and men curtailing their education, depresses parents’ lifetime earnings, and increases the odds of living in poverty.
The United States has one of the highest rates of youth violence in the developed world, as well as the highest rates of violent deaths among adolescents.
Nearly two-thirds of our high schools have security guards who carry firearms.
The United States leads the world in adolescent obesity and diabetes.
The rate of adolescent suicide in the United States is consistently higher than the international average, and suicide attempts and suicide ideation among American high-school students are both on the rise.
The capacity for self-regulation is probably the single most important contributor to achievement, mental health, and social success. The ability to exercise control over what we think, what we feel, and what we do protects against a wide range of psychological disorder, contributes to more satisfying and fulfilling relationships, and facilitates accomplishments in the worlds of school and work.
In today’s world, though, where formal education is increasingly important for success, people who are bad at reasoning, planning, and self-regulation are at a serious disadvantage, and the fact that the development of these abilities is highly sensitive to environmental influence is a mixed blessing.
The adolescent brain is extraordinarily sensitive to stress. The average age of onset for serious mental health problems is fourteen.
In all cultures and times, the mortality rate among boys spikes a few years after they become adolescents. It’s called the “accident hump”, and it occurs because the rise in testosterone that takes place at puberty makes males more aggressive and reckless.
A large survey of American children born in the early 1960s found that the average age of breast budding was close to thirteen years. By the mid-1990s, it had fallen to a little under ten.
Melatonin levels are sensitive to artificial as well as natural light. That’s why people are discouraged from staring at illuminated screens (like computer monitors, smartphones, or tablets) before they go to bed – the light they give off suppressed melatonin production, which makes it harder to feel sleepy. It’s little surprise that today’s teenagers, nearly all of whom have 24-7 access to television, computers, and other devices with glowing screens, are having more sleep problems than past generations. Your genes predispose you to go through puberty around a particular age, but the more fat cells you have, and the more light to which you have been exposed, the more likely it is that you will go through puberty on the early side of your inherited propensity.
The presence of chemicals in the environment that can accelerate puberty is so ubiquitous that children are exposed to them even when their parents are very careful about what they eat.
Menarche at twelve or earlier elevates a woman’s risk of breast cancer by 50 percent compared to menarche at sixteen.
Things that feel good, feel better during adolescence. A small structure inside the limbic system is the most active part of the brain for the experience of pleasure – it’s the center of the reward center – and it actually gets bigger as we grow from childhood into adolescence, but, alas, smaller as we age from adolescence to adulthood.
Although adolescents are relatively more attentive and responsive to rewards than adults, they’re actually less sensitive to losses. This bias is something that parents and teachers should keep in mind: it’s easier to change an adolescent’s behavior by motivating him with the prospect of a reward than by threatening him with a potential punishment.
Being upset, excited, or tired interferes more with prefrontal functioning during adolescence than during adulthood because the relevant brain circuits are not fully mature.
According to statistics from the FBI, most crimes are committed by adolescents.
In other words, it’s not necessarily overt peer pressure that leads adolescents to do more reckless things with their friends. It’s that being around friends when you are a teenager makes everything feel so good that you become even more sensitive to rewards than you ordinarily are, which leads you to take chances you wouldn’t otherwise take.
Risk taking is a natural, hardwired, and evolutionarily understandable feature of adolescence. It may no longer be especially adaptive in the world in which we live, but it is in our genes, and there isn’t much we can do to change that. We should devote fewer resources to trying to change how adolescents think, and focus on limiting opportunities for their inherently immature judgments to hurt themselves or others.
The marshmallow test seems to gauge something about people that stays with them as they grow up. More remarkably, the people who were delayers when they were four years old turned out to be more successful in life as well as in the lab. Life is constantly presenting us with choices between smaller immediate rewards and larger delayed ones.
From an earnings standpoint, going to college without getting a bachelor’s degree is now pretty much a complete waste of time.
Expanding opportunities to go to school without ensuring that people have the determination to take advantage of them is unlikely to succeed.
The United States spends more money, in absolute and relative dollars, on postsecondary education than nearly any other country. It has one of the highest rates of college entry in the industrialized world. Yet it is tied for last in the rate of college completion.
Matching former students and their careers with my recollection of their credentials at the time they applied, it struck me that the things we asked about on our admissions application were more or less useless in predicting future success in the field.
Only about 25 percent of school performance is accounted for by intelligence.
The abilities needed in most jobs can often be acquired after one is hired, but capacities like perseverance and conscientiousness must be nurtured before adulthood.
At its core, more than any other capacity, determination requires self-regulation.
In order to develop competence, children must learn from their mistakes.
You might be surprised to learn that, despite the stereotype of the pressure-cooked Asian student, the teen-suicide rate is higher in the United States than in China, Korea, Japan – or, for that matter, Germany.
Without changing the culture of student achievement, changes in instructors or instruction won’t, and can’t, make a difference.
The fact that Asian American children in particular do so well in our putatively terrible schools and with our ostensibly terrible teachers has nothing to do with what goes on in the classroom. It has everything to do with how they are raised and what their parents expect of them.
Most teenage delinquents don’t become persistent adult criminals. People tend to grow out of crime, just as with other sorts of risky and dangerous behavior, which decline as people mature through their twenties.
We spend our time telling adolescents what they shouldn’t do, rather than guiding them toward what they should – and can – do.
Atul Gwande is an unusually talented observer, thinker, and writer who is a surgeon. I have blogged about his books in the past. If you are interested in health and healthcare, I think that you will find his article on incremental healthcare to be intriguing. Although it is long, I think that it will hold your interest. It can be accessed through Google.
This book presents the growing evidence that we cannot continue to make progress in health care unless we consider the influences of our evolutionary past. Jeremy Taylor addresses seven areas:
- Our immune system;
- Issues regarding fertilization, pregnancy, and childbirth;
- The effects of upright posture;
- The development of the eye and macular degeneration;
- The challenges of cancer;
- Coronary artery disease; and
Each chapter stands on its own. I have chosen excerpts from his discussion of our immune system because these disorders affect such a large (and growing) number of our patients. “It is impossible to get to the root of the very peculiar human immune system and design really effective cures for allergies and autoimmune diseases without a fresh understanding of how the immune system evolved and for what reasons.” p. 7
“The world of our ancestors was a much dirtier place than it is now. Evolution took the expedient route, since microorganisms in prehistory could not be eradicated, of allowing humans to live with them rather than continually fight them. The great collateral cost of self-inflicted damage to our tissues caused by permanently raging immune systems was avoided by handing over the regulation of our immune systems to the microbes inside us, so that we ended up tolerating them. Evolution could not foresee a world where public hygiene, antibiotics, and chemicals that kill 99.9 percent of all household germs has so depleted this microbial population inside all of us that our immune systems no longer mature properly or are properly regulated, giving rise to dramatic increases in allergy and autoimmunity.” p. 8
The author reviews volumes of research and shares a number of anecdotes including one about a boy with autism whose behavior was so uncontrollable that he had to be institutionalized. Soon after institutionalization, he had a complete reversal in behavior which was caused by chigger bites. To perpetuate his recovery, his immune system is now being treated with infusions of pig whipworms, without which his behavior regresses. This case supports the “hygiene hypothesis which links the bacteria, fungi, and helminths (parasitic worms) in our guts, on our skin, and in our airways and vaginas, with a host of autoimmune and allergic diseases. There is mounting evidence that the composition of all these organisms, living on and inside us – collectively known as our microbiota – can offer protection against a formidable list of autoimmune diseases, including the inflammatory bowel diseases Crohn’s disease and ulcerative colitis, type 1 diabetes, rheumatoid arthritis, multiple sclerosis, and, as we have seen, mental health.” p. 17
“Of all the autoimmune diseases, type 1 (or early-onset) diabetes is rapidly becoming the main scourge of life in the modern, hygienic Western world. Karelia is a large northern European landmass that used to belong to Finland but was partly ceded to Russia during World War II. As a result, the country has been partitioned. Although Russian and Finnish Karelians have the same genetic makeup, including the same susceptibilities to diabetes, the differences in their socioeconomic status and health could not be more stark. One of steepest standard-of-living gradients in the world exists at the border between Russian and Finnish Karelia, with the latter having eight times the gross national product of the former. Yet the incidence of type 1 diabetes, and a host of other autoimmune diseases, is far higher on the Finnish side. Finnish Karelians have six times the incidence of diabetes, five times the incidence of celiac disease, six times more thyroid autoimmunity, and much higher allergy levels than Russian Karelians.” p. 21
“The baby is born with a gut that is almost completely sterile and must be populated immediately with bacteria. If it is breast-fed, it starts to receive one of the most extraordinary products in the natural world. Human breast milk contains a complex array of fats and sugars – fast food – but it also contains immunoglobulin A, an antibody that protects the lining of the human gut and prevents pathogens from attacking and perforating it. It has also been estimated that a breast-fed infant receives over 100 million immune cells every day, including macrophages, neutrophils, and lymphocytes, together with a host of cytokines, chemokines, and colony-sustaining factors – molecules that signal between cells of the immune system and promote their growth. Over seven hundred species of bacteria have been found in human breast milk. It also contains oligosaccharides which the baby is totally incapable of digesting. It is present to feed the bacteria from the breast milk which are colonizing in the baby’s gut”. p. 24
“Within a week or so after birth, the infant gut, originally sterile, has become colonized by up to 90 trillion microbes. The number of microbes in our guts eventually exceeds the total number of cells in our bodies by a factor of ten. Scientists now refer to the existence of a meta-genome to represent the combined genomes of human and microbiota, a superorganism in which we humans are the junior partner and without which we could no longer exist.” p. 27
“Our resident gut microbiota – the mass of over two thousand bacterial species identified as frequent, long-term inhabitants inside us – is extremely complex. Our relationship with them is so close and intertwined that many of the metabolic signatures that can be identified in human blood, sweat, and urine actually come from our commensal bacteria, not us.” P. 34
“The gut has been called the ‘second brain’ and has its own dedicated nervous system embedded throughout the gut wall. It is becoming increasingly clear that our gut molecules can communicate directly with our brains, and they are implicated in brain development, brain chemistry, behavior, and mental illness.” pp. 36 – 37
This is support for the importance of children getting outside to play in areas that have a variety of foliage comes from a different perspective – as long as we check carefully for tics.
A Prescription for Health in an Overtreated America
Nortin M. Hadler, MD
The theme of this book is clearly stated on the first page; “We are becoming increasingly medicalized, made to think that all life’s challenges demand clinical intervention, when the science dictate’s otherwise”. p. 1…
We don’t know why heart attacks are no longer so common or so evil. Medicine deserves little if any credit. But heart attacks are no longer your father’s heart attacks. p. 17