6Making Light of Sleep

Making Light of Sleep不要太在意睡眠All we have a clock located inside our brains. Similar to your bedside alarm clock，your internal clock2 runs on a 24-hour cycle. This cycle，called a circadian rhythm，helps control when you wake，when you eat and when you sleep. 我们每个人的大脑里都有一个像我们床边的闹钟一样的生物钟。

人脑里的生物钟24小时走一圈，这一圈也就是一次完整的昼夜节律，正是这个节律决定了我们吃饭、睡觉和起床的时间。

Somewhere around puberty，something happens in the timing of the biological clock. The clock pushes forward，so adolescents and teenagers are unable to fall asleep as early as they used to. When your mother tells you it's time for bed，your body may be pushing you to stay up3 for several hours more. And the light coming from your computer screen or TV could be pushing you to stay up even later. 青春期时，人的生物钟在定时方面会发生变化，生物钟会提前。

这时，青少年会比以前睡得晚，所以当你妈妈告诉你该睡觉时，你的生物钟可能会让你多推迟几小时，并且电脑或电视光线可能会导致你熬夜到更晚。

This shift4 is natural for teenagers. But staying up very late and sleeping late can get your body's clock out of sync with the cycle of light and dark5. It can also make it hard to get out of bed in the morning and may bring other problems，too. Teenagers are put in a kind of a gray cloud6 when they don't get enough sleep，says Mary Carskadon，a sleep researcher at Brown University in Providence，RI7 .It affects their mood and their ability to think and learn. 生物钟的这种变化对青少年说是正常的，但熬夜到太晚会打乱你生物钟与昼夜时间循环之间的平衡，这样就会带来一些问题，例如：早晨很难按时起床。

位于美国罗得州布郎大学睡眠方面的研究员Mary Carskadon说：“当青少年睡眠不足时会打不起精神，这将影响到他们心情、学习和思考问题的状态。

”But just like your alarm clock，your internal clock can be reset. In fact，it automatically resets itself every day. How? By using the light it gets through your eyes. 其实生物钟与闹钟一样，也是可调的，事实上，生物钟每天都在进行着自我调节，其方式就是通过你眼睛接收到光线的变化。

Scientists have known for a long time that the light of day and the dark of night play important roles in setting our internal clocks. For years，researchers thought that the signals that synchronize the body's clock8 were handled through the same pathways that we use to see. 很早之前，科学家就知道了昼夜光线强弱的变化对生物钟调节起到了重要的作用，长久以来，研究者们认为眼睛所接受到的平衡生物钟的光信号同样作用于人类的视觉系统。

But recent discoveries show that the human eye has two separate light-sensing systems. One system allows us to see. The second system tells our body whether it's day or night. 但最近几年的研究发现，人类眼睛有两个感光系统，一个是视觉系统，而另一个是感知昼夜的系统。

词汇：circadian/s3:'keidiən/ adj. 昼夜节奏的，生理节奏的adolescent/ædəu'lesənt/ n．青少年；adj．青少年的puberty/ 'pju:bəti/ n．发育；青春期sync/siŋk/ n. （口语）同步；和谐，协调synchronize/'siŋkrənaiz / V.（使）同时发生；（使）同步注释：1.make light of ：轻视，不在乎。

例如：We should not make light of their achievements．我们不应当低估他们的成就。

2. your internal clock ：指的是第一句中的a clock located inside our brains ，也即是第二段第一句中的the biological clock （生物钟）。

3. stay up：不睡觉，熬夜4. This shift：这种调整。

指上文所描述的由于生理时间的变化青少年上床时间越来越晚的现象。

5. get your body's clock out of sync with the cycle of light and dark ：打乱了你的生物钟与昼夜时间循环之间的平衡6. gray cloud ：提不起精神的状态7. Brown University in Providence，RI：位于美国罗得岛州普罗维登斯的布朗大学。

RI 是Rhode Island（罗得岛）的首字母缩写；Providence 是罗得岛州的首府。

布朗大学是美国一流大学，创建于1764 年，是世界闻名的美国“常春藤联盟”（还包括哈佛大学、耶鲁大学、普林斯顿大学、布朗大学、哥伦比亚大学、宾夕法尼亚大学、达特茅斯大学和康奈尔大学）中的一员。

8. the signals that synchronize the body's clock：平衡生物钟的光信号练习：1 .The clock located inside our brains is similar to our bedside alarm clock becauseA it controls when we wake，when we eat and when we sleep.B it has a cycle of 24 hours.C it is a cycle also called circadian rhythm.D it can alarm any time during 24 hours.2. What is implied in the second paragraph?A Young children's biological clock has the same rhythm with that of the teenagers.B People after puberty begin to go to bed earlier due to the change of the biological clock.C Children before puberty tend to fall asleep earlier at night than adolescents.D Teenagers go to bed later than they used to due to the light from the computer screen.3. In the third paragraph the author wants to tell the reader thatA it is natural for teenagers to stay up late and get up late.B staying up late has a bad effect on teenagers' ability to think and learn.C during puberty most teenagers experience a kind of gray cloud.D it is hard for teenagers to get out of bed in the morning.4. Which of the following statements is NOT true according to the fourth and fifth paragraphs?A Our biological clock resets itself automatically.B light gets through our eyes and resets our biological clock.C Our internal clock as well as the alarm clock can be reset automatically.D Our internal clock，like the alarm clock，can be reset.5. According to the last two paragraphs，what did the previous researchers think about the human eye's light-sensing system?A The human eye had two light-sensing systems.B The human eye had one light-sensing system.C The human eye could sense the light of day more quickly than the dark of night.D The human eye could reset our internal clocks in accordance with the alarm clocks.答案与题解：1.B 第一段第二句提供了答案。