问题详情：
If there was ever a study not to lose sleep over, it’s this one. people deprived(剥夺) of a good night’s rest are more likely to experience changes in brain activity that can increase the urge to eat high-calorie foods.
Matthew Walker at the University of California in Berkeley and his colleagues conducted the first study of brain activity in relation to food among sleep-deprived people. The team studied brain patterns in 23 people, first after a night of peaceful sleep and then after a night without sleep.
Sleep deprivation reduced activity in three areas of the brain that help, among other things, to process flavour signals. It also led to more activity in the brain, which helps govern the desire to eat. The team also found that volunteers considered pictures of high-calorie foods as more desirable after no sleep than after a good rest.
It may make evolutionary(进化的) sense, says Laurent Brondel at the University of Burgundy in Dijon, France. The long summer days at higher latitudes(纬度) deprive animals of sleep, but they use their time awake to eat more, which helps them get through the short days of winter when there is not enough food.
That’s only part of the story, though, says Stephanie Greer, another member of the team. The body does need more energy if someone remains awake for longer — but the high-calorie foods that become more desirable after sleep deprivation would more than meet this additional need. The changes in food desirability encouraged by the sleep-deprived brain may originally have been an important adaptation but today they no longer benefit our health.
Brondel agrees with this conclusion. “Sleep deprivation could change eating behaviour,” he says. Whatever the cause, there’s one clear message from the study. “These findings provide opportunities to adjust our environment and behaviour in new ways to handle such health problems,” Greer says. “Specifically, our study shows that one choice people can make is to regularly obtain enough amounts of sleep.”
28. Why did Matthew Walker conduct the study about sleep-deprived people?
A. To learn more about sleep patterns.
B. To warn of the danger of high-calorie foods.
C. To know the importance of getting enough rest.
D. To find relations between brain activity and food.
29. Which of the following is the correct cause-and-effect diagram?
A. sleep → brain activity → appetite(胃口)
B. sleep → appetite → brain activity
C. brain activity → sleep → appetite
D. appetite → brain activity → sleep
30. Sleep deprivation of animals at higher latitudes ____.
A. makes them evolve
B. does harm to their health
C. helps them survive winters
D. keeps them awake in winters
31. What does the author mean by saying “That’s only part of the story” in Paragraph 5?
A. The high-calorie foods are more desirable.
B. Sleep deprivation also has its bad effects.
C. Our body is in need of more energy.
D. The changes do animals harm.
【回答】
BCCA
知识点：*经济文化类阅读
题型：阅读理解
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