Passage 5
Birds that are literally half asleep—with one brain hemisphere alert and the other sleeping—control which side of the brain remains awake, according to a new study of sleeping ducks.
Earlier studies have documented half brain sleep in a wide range of birds. The brain hemispheres take turns sinking into the sleep stage characterized by slow brain waves. The eye controlled by the sleeping hemisphere keeps shut, while the wakeful hemisphere’s eye stays open and alert. Birds also can sleep with both hemispheres resting at once.
Decades of studies of bird flocks led researchers to predict extra alertness in the more vulnerable, end of the row sleepers. Sure enough, the end birds tended to watch carefully on the side away from their companions. Ducks in the inner spots showed no preference for gaze direction.
Also, birds dozing (打盹) at the end of the line resorted to single hemisphere sleep, rather than total relaxation, more often than inner ducks did. Rotating 16 birds through the positions in a four duck row, the researchers found outer birds half asleep during some 32 percent of dozing time versus about 12 percent for birds in internal spots.
“We believe this is the first evidence for an animal behaviorally controlling sleep and wakefulness simultaneously in different regions of the brain,” the researchers say.
The results provide the best evidence for a long standing supposition that single hemisphere sleep evolved as creatures scanned for enemies. The preference for opening an eye on the lookout side could be widespread, he predicts. He’s seen it in a pair of birds dozing side by side in the zoo and in a single pet bird sleeping by a mirror. The mirror side eye closed as if the reflection were a companion and the other eye stayed open.
Useful as half sleeping might be, it’s only been found in birds and such water mammals (哺乳动物) as dolphins, whales, and seals. Perhaps keeping one side of the brain awake allows a sleeping animal to surface occasionally to avoid drowning.
Studies of birds may offer unique insights into sleep. Jerome M. Siegel of the UCLA says he wonders if birds’ half brain sleep “is just the tip of the iceberg (冰山)” He speculates that more examples may turn up when we take a closer look at other species.
Passage 3
Taking charge of yourself involves putting to rest some very prevalent myths. At the top of the list is the notion that intelligence is measured by your ability to solve complex problems; to read, write and compute at certain levels; and to resolve abstract equations quickly. This vision of intelligence asserts formal education and bookish excellence as the true measures of self fulfillment. It encourages a kind of intellectual prejudice that has brought with it some discouraging results. We have come to believe that someone who has more educational merit badges, who is very good at some form of school discipline is “intelligent.” Yet mental hospitals are filled with patients who have all of the properly lettered certificates. A truer indicator of intelligence is an effective, happy life lived each day and each present moment of every day.
If you are happy, if you live each moment for everything it’s worth, then you are an intelligent person. Problem solving is a useful help to your happiness, but if you know that given your inability to resolve a particular concern you can still choose happiness for yourself, or at a minimum refuse to choose unhappiness, then you are intelligent. You are intelligent because you have the ultimate weapon against the big N.B.D.—Nervous Break Down.
“Intelligent people do not have N.B.D.’s because they are in charge of themselves. They know how to choose happiness over depression, because they know how to deal with the problems of their lives.
You can begin to think of yourself as truly intelligent on the basis of how you choose to feel in the face of trying circumstances. The life struggles are pretty much the same for each of us. Every one who is involved with other human beings in any social context has similar difficulties. Disagreements, conflicts and compromises are a part of what it means to be human. Similarly, money, growing old, sickness, deaths, natural disasters and accidents are all events which present problems to virtually all human beings. But some people are able to make it, to avoid immobilizing depression and unhappiness despite such occurrences, while others collapse or have an N.B.D. Those who recognize problems as a human condition and don’t measure happiness by an absence of problems are the most intelligent kind of humans we know; also, the most rare.