the brain’s appetite for energy is enormous. The brain represents only about 2 percent of most people’s body weight, yet it accounts for about 20 percent of the body’s total energy usage—about 10 times more than would be expected. When the brain is fully working, it uses more energy per unit of tissue weight than a fully exercising quadricep. In fact, the human brain cannot simultaneously activate more than 2 percent of its neurons at any one time. More than this, and the glucose supply becomes so quickly exhausted that you will faint.
Civilization, while giving us such seemingly forward advances as modern medicine and spatulas, also has had a nasty side effect. It gave us more opportunities to sit on our butts. Whether learning or working, we gradually quit exercising the way our ancestors did. The result is like a traffic wreck.
There are two compelling business reasons for such radical ideas. Business leaders already know that if employees exercised regularly, it would reduce health-care costs. And there’s no question that cutting in half someone’s lifetime risk of a debilitating stroke or Alzheimer’s disease is a wonderfully humanitarian thing to do. But exercise also could boost the collective brain power of an organization. Fit employees are capable of mobilizing their God-given IQs better than sedentary employees. For companies whose competitiveness rests on creative intellectual horsepower, such mobilization could mean a strategic advantage. In the laboratory, regular exercise improves—sometimes dramatically so—problem-solving abilities, fluid intelligence, even memory.
The last step in declarative processing is forgetting. The reason forgetting plays a vital role in our ability to function is deceptively simple. Forgetting allows us to prioritize events. Those events that are irrelevant to our survival will take up wasteful cognitive space if we assign them the same priority as events critical to our survival.
Dement is a white-haired man with a broad smile who at this writing is in his late 70s. He says pithy things about our slumbering habits, such as “Dreaming permits each and every one of us to be quietly and safely insane every night of our lives. Dement
One night’s loss of sleep resulted in about a 30 percent loss in overall cognitive skill, with a subsequent drop in performance. Bump that to two nights’ loss, and the figure becomes 60 percent. Other studies extended these findings. When sleep was restricted to six hours or less per night for just five nights, for example, cognitive performance matched that of a person suffering from 48 hours of continual sleep deprivation.
Many of the same mechanisms that cause you to shrink in horror from a predator are also used when you are having sex—or even while you are consuming your Thanksgiving dinner. To your body, saber-toothed tigers and orgasms and turkey gravy look remarkably similar. An aroused physiological state is characteristic of both stress and pleasure.
These days, our stresses are measured not in moments with mountain lions, but in hours, days, and sometimes months with hectic workplaces, screaming toddlers, and money problems. Our system isn’t built for that. And when moderate amounts of hormone build up to large amounts, or when moderate amounts of hormone hang around too long, they become quite harmful. That’s how an exquisitely tuned system can become deregulated enough to affect a dog in a metal crate—or a report card, or a performance review.
Not surprisingly, people who experience chronic stress are sick more often. A lot more often. One study showed that stressed individuals were three times as likely to suffer from the common cold.
When these marriages started their transition to parenthood, Gottman noticed that the couple’s hostile interactions skyrocketed. There were many causes, ranging from chronic sleep deprivation to the increased demands of a helpless new family member (little ones typically require that an adult satisfy some demand of theirs about 3 times a minute). By the time the baby was 1 year old, marital satisfaction had plummeted 70 percent. At that same point, the risk for maternal depression went from 25 percent to a whopping 62 percent. The couples’ risk for divorce increased, which meant American babies often were born into a turbulent emotional world.
In recognition of this fact, Starbucks does not allow employees to wear perfume on company time. It interferes with the seductive smell of the coffee they serve and its potential to attract customers.
Three researchers created a fictitious assistant vice president of an aircraft company. Four groups of experimental subjects, with equal numbers of men and women in each group, were asked to rate this fictional person’s job performance. Each group was given the vice president’s brief job description, but the first group also was told that the vice president was a man. They were asked to rate both the competence and the likability of the candidate. They gave a very flattering review, rating the man “very competent” and “likable.” The second group was told that the vice president was a woman. She was rated “likable” but “not very competent.” All other factors were equal. Only the perceived gender had changed.
There is terrible inequality between the two chromosomes. The X chromosome does most of the heavy developmental lifting, while the little Y has been shedding its associated genes at a rate of about five every one million years, committing suicide in slow motion. It’s now down to less than 100 genes. By comparison, the X chromosome carries about 1,500 genes, all necessary participants in embryonic construction projects. These are not showing any signs of decay.
They never do it. X inactivation does not occur in guys. And because males must get their X from Mom, all men are literally, with respect to their X chromosome, Momma’s Boys—unisexed. That’s very different from their sisters, who are more genetically complex. These bombshells describe our first truly genetic-based findings of potential gender differences.
“Seven Rules of Management from a Baby’s Perspective”: If I want it, it is mine. If I give it to you and change my mind later, it is mine. If I can take it away from you, it is mine. If we are building something together, all of the pieces are mine. If it looks just like mine, it is mine. If it is mine, it will never belong to anybody else, no matter what. If it is yours, it is mine.
I think that we must do a better job of encouraging lifelong curiosity, in our workplaces and especially in our schools.