雅思阅读模拟题insomnia–the enemy of sleep.pdfVIP

智 课 网 雅 思 备 考 资 料 雅思阅读模拟题INSOMNIA–THE ENEMY OF SLEEP ?????? 这篇雅思阅读模拟题的主要内容是讨论了对于睡眠来说最重要 的敌人，就是失眠的现象。这篇文章从各种方面讨论了失眠对于人类睡 眠和身体的影响。我们一起来看看吧。 A It is not unusual to have sleep troubles from time to time. But, if you feel you do not get enough sleep or satisfying sleep, you may have insomnia, a sleep disorder. People with insomnia have one or more of the following: difficulty falling asleep, waking up often during the night and having trouble going back to sleep, waking up too early in the morning and unrefreshing sleep. Insomnia is not defined by the number of hours you sleep every night. The amount of sleep a person needs varies. While most people need between 7 and 8 hours of sleep a night, some people do well with less, and some need more. B Insomnia occurs most frequently in people over age 60, in people with a history of depression, and in women, especially after menopause. Severe emotional trauma can also cause insomnia with divorced, widowed and separated people being the most likely to suffer from this sleep disorder. Stress, anxiety, illness and other sleep disorders such as restless legs syndrome are the most common causes of insomnia. An irregular work schedule, jet lag or brain damage from a stroke or Alzeimer’s disease can also cause insomnia as well as excessive use of alcohol or illicit drugs. It can also accompany a variety of mental illnesses. C The mechanism that induces sleep is not known. When it becomes dark, the pineal gland in the brain secretes a hormone called melatonin, which is thought to induce sleep. Exactly why sleep is necessary for good health and efficient mental functioning is unknown. We do know that sleep consists of two very different states: rapid eye movement (REM) sleep and non-REM sleep. In REM sleep, dreams occur, the eyes move under the closed lids and there is an increase in oxygen consumption, blood flow and neural activity. REM sleep occurs four or five times during a night. Beginning