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Why do we need sleep?
Is bedtime just a time for dreaming? Do our brainsturn off for the night? What if I told you thatscientists recently discovered that our brains may be just as busy at night as they are duringthe day?
While we sleep, our brains are doing much more than getting ready for the next day.Researchers at the University of Rochester found that the brain may be busy cleaning house --cleaning out harmful waste materials.
As with many studies, the researchers turned to mice for help. They studied mice that hadcolored dye injected into their brains. They observed the mice brains as they slept and whenthey were awake. The researchers say they saw that the brains of sleeping mice were hard atwork.
Working Double Duty
Dr. Maiken Nedergaard led the study. The brain expert says our brains perform two verydifferent jobs. It seems they have daytime jobs. Later they "moonlight" at a nighttime job.
"Moonlighting" is working a nighttime job in addition to a day job. And this study says that iswhat our brains seem to be doing – working an extra job at night without additional pay forovertime.
"When we are awake, the brain cells are working very hard at processing all the informationabout our surroundings. Whereas when we are asleep, they work very, very hard at removingall the waste that builds up when we are awake."
The researchers say that the waste material includes poisons, or toxins, responsible for braindisorders such as Alzheimer's disease.
They also found that during sleep, the brain's cells shrink, or become smaller. This shrinkingpermits waste to be removed more effectively.
Dr. Nedergaard says these toxins end up in the liver. There, they are broken down and thenremoved from the body.
"So our study suggests we need to sleep because we have a macroscopic cleaning system thatremoves many of the toxic waste products from the brain."
The brain's cleaning system could only be studied with new imaging technologies. The testanimal must be alive in order to see for this brain process to be seen as it happens.
Dr. Nedergaard says the next step is to look for the process in human brains. She said theresults demonstrate just how important sleep is to health and fighting disease. The researchmay also one day lead to treatments to prevent or help fight neurological disorders.
7 Tips for Better Sleeping
Do you have trouble sleeping? Not being able to sleep is called insomnia. According to theUnited States National Sleep Foundation, here are some tips for a good night's sleep:
Go to bed about the same time each night, even on weekends. This helps to "set" your body's"sleep clock."
Exercise every day.
Have a calm, relaxing bedtime routine – Take a warm bath or drink a hot cup of tea.
Try not to take long naps during the day. Periods of sleep during the daytime can interferewith sleep at night.
Make sure you have a pleasant environment where you sleep. For most people, a cool, quietand dark room is best for sleeping.
Avoid using television, computers and other electronic screens before bedtime.
Also avoid alcohol, cigarettes and heavy meals before bedtime.
And from VOA Learning English, that's the Health Report. I'm Anna Matteo.
Do you suffer from insomnia? Do you have more suggestions for a good night's sleep. Let usknow in our comment section. |
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发表于 2016-7-28 21:08:51