题目内容
A．In the 1920' s.B．In the 1930' s.C．In the 1940' s.D．In the 1950' s.
查看答案
搜索结果不匹配？点我反馈
更多问题
Our dreams combine verbal, visual and emotional stimuli into a sometimes broken, nonsensical but often entertaining story line. We can sometimes even solve problems in our sleep. Or can we？ Many experts disagree on exactly what the purpose of our dreams might be. Are they strictly random brain impulses, or are our brains actually working through issues from our daily life while we sleep--as a sort of coping mechanism？ Should we even bother to interpret our dreams？ Many say yes, that we have a great deal to learn from our dreams.
Why do we Dream？
For centuries, we've tried to figure out just why our brains play these nightly shows for us. Early civilizations thought dream worlds were real, physical worlds that they could enter only from their dream state. Researchers continue to toss around many theories about dreaming. Those theories essentially fall into two categories:
The idea that dreams are only physiological stimulations
The idea that dreams are psychologically necessary
Physiological theories are based on the idea that we dream in order to exercise various neural connections that some researchers believe affect certain types of learning. Psychological theories are based on the idea that dreaming allows us to sort through problems or events of the day or things that are requiring a lot of our attention. Some of these theorists think dreams might be prophetic. Many researchers and scientists also believe that perhaps it is a combination of the two theories.
Dreaming and the Brain
When we sleep, we go through five sleep stages. The first stage is a very light sleep from which it is easy to wake up. The second stage moves into a slightly deeper sleep, and stages three and four represent our deepest sleep. Our brain activity throughout these stages is gradually slowing down so that by deep sleep, we experience nothing but delta brain waves--the slowest brain waves. About 90 minutes after we go to sleep and after the fourth sleep stage, we begin REM sleep.
Rapid eye movement(REM)was discovered in 1953 by University of Chicago researchers Eugene Aserinsky, a graduate student in physiology, and Nathaniel Kleitman, Ph. D. , chair of physiology. REM sleep is primarily characterized by movements of the eyes and is the fifth stage of sleep.
How to Improve Your Dream Recall
It is said that five minutes after the end of a dream, we have forgotten 50 percent of the dream's content. Ten minutes later, we've forgotten 90 percent of its content. Why is that？ We don't forget our daily actions that quickly. The fact that they are so hard to remember makes their importance seem less.
There are many resources both on the Web and in print that will give you tips on how to improve your recall of dreams. Those who believe we have a lot to learn about ourselves from our dreams are big proponents of dream journals. Here are some steps you can take to increase your dream recall:
When you go to bed, tell yourself you will remember your dreams.
Set your alarm to go off every hour and a half so you'll wake up around the times that you leave REM sleep--when you're most likely to remember your dreams.(Or, drink a lot of water before you go to bed to ensure you have to wake up at least once in the middle of the night!)
Keep a pad and pencil next to your bed.
Try to wake up slowly to remain within the "mood" of your last dream.
Common Dream Themes and Their Interpretations
Being naked in public
Most of us have had the dream at some point that we're at school, work or some social event, and we suddenly realize we forgot to put on clothes! Experts say this means:
We're trying to hide something(and without clothes we have a hard time doing that).
We're not prepared for something, like a presenta
A．whether they should go for a holidayB．where they should go for the holidayC．how they
Section B
Directions: There are 2 passages in this section. Each passage is followed by some questions or unfinished statements. For each of them there are four choices marked A, B, C and D. You should decide on the best choice.
Space is dangerous place, not only because of meteors(流星)but also because of rays from the sun and other Stars. The atmosphere again acts as our protective blanket on earth. Light gets through and this is essential for plants to make the food which we eat. Heat, too, makes our environment endurable. Various kinds of rays come through the air from outer space, but enormous quantities of radiation from the sun are screened off. As soon as men leave the atmosphere they are exposed to this radiation but their spacesuits or the walls of their spacecraft, if they are inside, do prevent a lot of radiation damage.
Radiation is the greatest known danger to explorers in space. The unit of radiation is called "rem". Scientists have reason to think that a man can put up with far more radiation than 0.1 rem without being damaged; the figure of 60 rems has been agreed on. The trouble is that it is extremely difficult to be sure about radiation damage -a person may feel perfectly well, but the cells of his or her sex organs may be damaged and this will not be discovered until the birth of deformed(畸形的)children or even grandchildren. Missions of the Apollo flights have had to cross belts of high radiation and during the outward and return journeys, the Apollo crew accumulated a large amount of rems. So far, no dangerous amounts of radiation have been reported, but the Apollo missions have been quite short. We simply do not know yet how men are going to get on when they spend weeks and months outside the protection of the atmosphere, working in a space laboratory. Drugs might help to decrease the damage done by radiation, but no really effective ones been found so far.
According to the first paragraph, the atmosphere is essential to man in that ______.
The word" burnout"(Para. , Line 3 )here refers to the state of ______.
微信支付 
支付宝支付