The next time you think about going without sleep, consider this: Laboratory animals that are kept awake for long periods of time … die. Yet sleep scientist Ying-Hui Fu at the University of California, San Francisco, says little is known about the basic need for sleep. She says: “We do not know why some humans need more sleep; why some humans need less sleep; why, when we do not sleep, we do not function well.” But here is something that scientists now know: A team led by Professor Fu has reported the first genetic link to how much sleep we need.
The team was looking for a natural clock in the body that controls sleep and wakefulness. What they found was a genetic abnormality. People who have this mutation need less sleep than others. But keep in mind that the scientists say this mutated gene may be rare. The study involved two members of an extended family. They did fine on just six hours of sleep a day. Studies have shown that over time, most humans need eight to eight and a half hours of sleep for the best health.
To test their theories, the scientists genetically engineered the mutation in mice. The mice with the mutation needed less sleep than normal mice. They were also more active even after being kept awake. The study appears in the journal Science.The researchers will continue to study the mice to test whether the gene is related to other medical conditions. And they will study whether it is involved in controlling sleep quantity alone, or also what scientists call the “wakefulness-behavioral drive.” This drive is important for getting food, shelter and mates.
How you sleep can be as important as how much you sleep — especially for newborn babies. A new report says images in parenting and women’s magazines may send the wrong message about how to put babies to bed. The study found that more than one-third of the pictures in women’s magazines showed babies in unsafe sleep positions. They showed babies sleeping on their sides or stomachs. Also, only a third of the pictures showed sleep environments considered safe by the American Academy of Pediatrics.
The academy says babies should sleep on their backs. They should be placed on a separate sleep surface from their parents, without blankets, pillows or other soft bedding. These guidelines have reduced cases of sudden infant death syndrome in the United States. And thats the VOA Special English Health Report.
Words in This Story
laboratory – n. a room or building with scientific equipment for doing scientific tests or for teaching science, or a place where chemicals or medicines are produced
genetic – adj. belonging or relating to genes (= parts of the DNA in cells) received by each animal or plant from its parents
wakefulness – n. the state of being wakeful (= not asleep or able to sleep)
abnormality – n. something abnormal, usually in the body
mutation – n. the way in which genes change and produce permanent differences
mutate – v. to develop new physical characteristics because of a permanent change in the genes.
These changes can happen naturally or can be produced by the use of chemicals or radiation
theory – n. a formal statement of the rules on which a subject of study is based or of ideas that are suggested to explain a fact or event or, more generally, an opinion or explanation
paediatrics – n. (US pediatrics) the science or study of medical care for children
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