Folk Wisdom: Was Grandma Right?

Since the brain is the mechanism that generates behavior, where we find behavioral differences, we should also find neurological differences. Indeed, research suggests a host of differences between male and female brains. For example, although, on average, male brains are larger than female brains, the hemispheres of the brain seem to be better connected in females, which may help explain why females are more sensitive and emotional than males.

Behavior is also driven by hormones. Here, too, there are significant gender differences. From birth, testosterone levels are higher in males, which helps to account for males' aggressiveness. June Reinisch, Ph.D., then at Indiana University, studied boys and girls whose mothers has been exposed to antimiscarriage drugs that mimic testosterone. Not surprisingly, she found that these children of both sexes were considerably more aggressive than their counterparts with normal testosterone levels. But even among the exposed children, the boys were more aggressive than the girls.

So boys will indeed be boys (and by implication, girls will be girls). But this is only true "on average." Male and female traits overlap considerably, which means that a particular male could be more emotional than most females and a particular female could be better at math than most males. To be fair, you have to go case by case.

Early to Bed, and Early to Rise, Makes a Man Healthy, Wealthy, and Wise

This proverb, often attributed to Ben Franklin, actually seems to have originated in the late 1400s, and Franklin may have lifted it from a collection of adages published in 1656. Historical trivia aside, research on sleep suggests that the proverb gives sound advice—but only because our culture is out-of-synch with the biology of nearly half the population.

Here's how it works: it's long been know that the body has natural rhythms. Those that occur on a 24-hour cycle are called "circadian" and include cycles of temperature change, wakefulness, and eating. There are two distinctly different circadian rhythm patterns. "Larks"—who show what researchers call "morningness" (honest!)—are people whose peak early in the day. Not surprisingly, larks awaken early and start the day strong. "Owls"—people inclined toward "eveningness"—peak late in the day. In both cases, the peaks are associated with better performance on memory tasks, quicker reaction times, heightened alertness, and cheerful moods. Some people are extreme larks or owls, others are moderates, and a few fit neither category.

There's a problem here, especially if, like me, you're an extreme owl. The trouble is that many important human activities—business meetings, job interviews, weddings, classes, and so on—are conducted during daylight hours, when larks have a distinct advantage. Not surprisingly, owls spend much of their time griping about how out-of-synch they seem to be.

A study of college students by Wilse B. Webb and Michael H. Bonnet, of the University of Florida, paints a grim picture for people like me: "Larks reported waking up when they expected to, waking up feeling more rested, and waking up more easily than the owls." Larks also reported having "fewer worries" and getting "more adequate sleep," and they awakened feeling physically better than owls. The differences were even greater, moreover, when owls tried to adapt to the lark sleep pattern. What's more, these problems can impair not only owl's sense of restedness but also their bank account; a study of Navy personnel suggests that people who sleep well make considerably more money than people who sleep poorly.

The long and short of it is that if your biorhythms allow you easily to "go to bed with the lamb and rise with the lark" (another old proverb), you may indeed end up with more money, better health, and more life satisfaction—but only because your internal clock is more in-synch with the stock exchange.

Spare the Rod and Spoil the Child