Dreams have fascinated people for thousands of years, yet we struggle to understand their purpose. A more recent theory suggests nighttime dreams protect visual areas of the brain from being taken over during sleep by other sensory functions, such as hearing or touch.
David Eagle-man, a neuroscience at Stanford University, has proposed the idea that dreaming is necessary to protect the visual cortex (大脑皮层)—the part of the brain responsible for processing vision. He argues that neurons (神经元) compete for survival. The brain, Eagle-man explains, distributes its resources by “implementing a do-or-die competition” for brain territory in which sensory areas “gain or lose neural territory when inputs slow, stop or shift.” Eagle-man points to people who lose sight or hearing. They show heightened sensitivity in the remaining senses because the region of the brain normally used by the lost sense is taken over by other senses.
When you sleep, you can smell, hear and feel, but visual information is absent —except during REM sleep. About 90 minutes after drifting off to sleep, you enter REM. It begins when neurons in your brain stem signal the beginning of two important tasks. Activity of these neurons, for one, paralyze major muscles, preventing the sleeper from acting out what is happening in the dream. Also, these brain cells send messages directly to the visual cortex, which starts the dreaming process. Scans of dreaming people show most of the brain activity associated with REM is within the visual cortex. Dreams are the brain’s way of fighting takeover from other senses, according to Eagle-man.
Eagle-man says that his theory can accommodate other explanations for dreams and that REM sleep may serve many purposes besides protecting the visual cortex. Think of dreaming like a computer screen saver that is set to go off every 90 minutes —except that instead of protecting against frozen images, dreams prevent the visual cortex from being occupied by other functions.
1. What is Eagle-man’s primary theory about dreams?| A．They strengthen sensory functions. | B．They process emotional experiences. |
| C．They safeguard certain brain territory. | D．They heighten visual responsiveness. |
| A．Precise selection. | B．Desperate struggle. | C．Rapid adaptation. | D．Harmonious balance. |
| A．It lasts for about 90 minutes. | B．It consists of two critical stages. |
| C．It allows sleepers to act out their dreams. | D．It starts with brain stem’s signaling process. |
| A．To show their creative aspect. | B．To highlight their randomness. |
| C．To signify their repetitive nature. | D．To illustrate their protective function. |
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【推荐1】A good modern newspaper is an extraordinary piece of reading. It's great first for what it contains：the range of news from local crime to international politics, from sports to business，from fashion to science, and the range of comment and special feature(特写) as well，from editorial page to feature articles and interviews to criticism of books, art theatre and music.
A newspaper is even greater for the way one reads it：never completely, never straight through，but always by jumping from here to there, in and out, glancing at one piece，reading another article all the way through, reading just a few paragraphs of the text.
A good modern newspaper offers a variety(多样性) to attract many different readers, but far more than the reader is interested in. What brings this variety together in one place is its topicality(时事性), its immediate relation to what is happening in your world and your locality now. But immediacy and the speed of production that goes with it also mean that much of what appears in a newspaper has no more than transient(短暂的) value.
For all these reasons, no two people really read the same paper：what each person does is to put together, out of the pages of that day's paper, his own selection and order, his own newspaper. For all these reasons, reading newspapers efficiently, which means getting what you want from them without missing things you need and without wasting time，demands skill and self-awareness as you change and apply the techniques of reading.
1. A modern newspaper is great for all the following EXCEPT its________.| A．wide variety | B．similar style |
| C．speed in reporting news | D．popularity |
| A．people look through the news they are interested in |
| B．different people prefer different newspapers |
| C．people are rarely interested in the same kind of news |
| D．people have different views about what a good newspaper is |
| A．apply reading techniques skillfully |
| B．jump from one newspaper to another |
| C．appreciate the variety of a newspaper |
| D．usually read a newspaper selectively |
| A．How to read newspaper? | B．Where to find a good newspaper? |
| C．What is a good newspaper? | D．Newspaper. |
【推荐2】All animals play. Running and rolling are ways for them to have fun. But it also seems to be how they communicate and strengthen bonds with each other.
When a dog comes up to another dog, front legs bowed or his tail high or wagging, his friend knows he wants to play. But new research shows that this play behavior is surprisingly similar when horses and dogs play.
“Up to now, most studies have focused on dog-human play due to the important implications that such studies have in understanding the special relationship we establish with our pets,” researchers from Italy wrote in the journal Behavioural Processes. “Here, we focused on social play between dogs and horses.”
To study communication among different species, Elisabetta Palagi and her colleagues from the University of Pisa found 20 YouTube videos of dogs and horses playing where their interactions lasted at least 30 seconds. They analyzed the videos, looking for specific patterns of play.
They found that while playing, both dogs and horses often had relaxed, open mouths, which is a common playful facial expression in animals. Some also copied each others' movements, like pretending to bite, playing with an object, or rolling on their backs on the ground. The team also found that the dogs and horses copied each other's facial expressions. This behavior, called rapid facial mimicry, has been seen before in dogs and sun bears, points out National Geographic. But it has never been documented between animals of different species.
“A 2000-pound horse can play with a relatively tiny dog because the two are able to communicate their intentions. It's an important study because it shows how two animals who look and behave so differently can manage to discuss how to play in a way that's comfortable for both,” Barbara Smuts, a behavioral ecologist at the University of Michigan, told National Geographic.
1. How does a dog express his intention to play?| A．By bowing his back legs. | B．By crossing his legs. |
| C．By waving his tail high. | D．By raising his head. |
| A．By referring to some books about animal species. |
| B．By analyzing videos of dogs playing with horses. |
| C．By playing with some dogs and horses separately. |
| D．By conducting an experiment on dogs and sun bears. |
| A．Dogs like to play with horses best. |
| B．Dogs and horses imitate each other's actions. |
| C．Animals show happiness by opening their mouths. |
| D．Different animals have different patterns of play. |
| A．Supportive. | B．Doubtful. | C．Opposed. | D．Unconcerned. |
【推荐3】When you think of a national park, you generally picture fresh air and wild animals, right? Well, now you’re going to have to add tea shops and something called “the Underground” to your definition, because London, England has signed up to be the first “National Park City.”
London was founded by the Romans around 2,000 years ago and people have continually lived there since then. In all that time, however, nobody had the idea to replace all the parks with big box stores or high buildings, which means London already has a much lower urban density than most of the world’s cities. Nowadays about a third of the city is green space.
In July 2019, London announced its willingness to become the world’s first National Park City. Now the city is moving toward the goal of achieving 50% green space by the year 2050 by connecting and increasing public parks, greening unused parking lots and the private yards of existing and new houses, and fixing some green roofs on existing buildings.
“Encouraged by the aims and values of our rural national parks, the London National Park City is basically about making life better in the capital through both small everyday things and long-term thinking,” Daniel Raven-Ellison, who began the movement to make London a National Park City six years ago, said. “We’ve been doing that in London for centuries, which is why London is so green.” It’s about going further to make the city greener, healthier and wilder; making the city richer in wildlife.
London will have a much easier job achieving this type of green transformation than more densely-urbanized cities like Paris and New York, which have 10% and 27% green space, respectively. But that doesn’t mean it’s not possible — the National Park City Foundation hopes to include 25 more cities in addition to London by the year 2025. Glasgow, Scotland and Newcastle upon Tyne in northeast England are both considering becoming National Park Cities.
1. What makes London more likely to become a National Park City than other cities?| A．Its smaller population. | B．Its locals’ requirements. |
| C．Its government’s strict law. | D．Its wider area of green space. |
| A．About 10%. | B．About 27%. | C．About 33%. | D．About 50%. |
| A．In Paragraph 1. | B．In Paragraph 2. | C．In Paragraph 3. | D．In Paragraph 4. |
| A．The values of newly-founded parks. | B．The importance of his movement. |
| C．The influence of green space on cities. | D．The preparation for setting up a movement. |
| A．London is leading the world in park construction |
| B．London becomes the world’s first National Park City |
| C．London is listed as the world’s most-visited city |
| D．London has built the world’s first underground park |
【推荐1】Most environmental pollution comes from humans and their inventions. The electric bulbs are thought to be one of the greatest human inventions of all time. However, too much of a good thing has started to negatively impact the environment. Light pollution, the extreme or inappropriate use of outdoor artificial light, is affecting human health and wildlife behavior. There is a global movement to reduce light pollution, and everyone can help.
Light pollution is a global issue. This became particularly obvious when the World Atlas (地图册)of Night Sky Brightness, a computer-generated map based on thousands of satellite photos, was published in 2016. Vast areas of North America, Europe, the Middle East, and Asia are glowing with light, while only Siberia, the Sahara, and the Amazon are in total darkness.
Artificial light can wreak havoc on natural body rhythms in both humans and animals. It interrupts sleep and confuses the circadian rhythm(生理节奏)一the internal, twenty-four-hour clock that guides day and night activities and affects physiological processes in nearly all living organisms. One of these processes is the production of the hormone melatonin(褪黑素), which is released when it is dark and is prevented when there is light. An increased amount of light at night lowers melatonin production, which results in lack of sleep, headaches, stress, anxiety, and other health problems. Blue light, in particular, has been shown to reduce levels of melatonin in humans. It is found in cell phones and other computer devices, as well as in light-emitting diodes (LEDs), the kinds of bulbs that have become popular at home and in industrial and city lighting due to their low cost and energy efficiency.
Studies show that light pollution is also impacting animal behaviors, such as migration (迁徙)patterns and habitat formation. Because of light pollution, sea turtles guided by moonlight during migration get confused, lose their way, and often die. Large numbers of insects, a primary food source for birds and other animals, are drawn to artificial light and are instantly killed upon contact with light sources. Even animals living under the deep sea may be affected by underwater artificial lighting. One study looked at how animals in sea responded to brightly lit panels put under water off the coast of Wales. Fewer filter feeding animals(滤食性动物), such as the sea squirt(海鞘), made their homes near the lighted panels. This could mean that the artificial light is altering ocean ecosystems.
The good news is that light pollution, unlike many other forms of pollution, is reversible(可逆的)and each one of us can make a difference! Now, many people are taking action to reduce light pollution and bring back the natural night sky. Individuals are urged to use outdoor lighting only when and where it is needed, to make sure outdoor lights are properly shielded (遮挡)and direct light down instead of up into the sky, and to close window blinds, shades, and curtains at night to keep light inside.
1. What does the underlined phrase “wreak havoc on” in Para. 3 probably mean?| A．Greatly improve. | B．Well maintain. |
| C．Strictly manage. | D．Seriously damage. |
| A．Light pollution was first studied as a global issue in 2016. |
| B．Deep-sea environment can help animals avoid light pollution. |
| C．Artificial light affects the sense of direction and habits of animals. |
| D．LEDs can be used more because of low cost and energy efficiency. |
| A．Unconcerned. | B．Negative. |
| C．Neutral. | D．Positive. |
| A．To call on people to reduce light pollution. |
| B．To discuss fors and againsts of artificial light. |
| C．To give suggestions to protect environment. |
| D．To show development prospect of artificial light. |
【推荐2】Tired of your ordinary earthly vacations? Some day soon you might be able to board a rocket and get a room with a view of the whole planet — from a hotel in space.
At least, that is the sales pitch(高调) of several companies racing to become the first to host guests in orbit on purpose-built space stations.
“It sounds kind of crazy to us today because it is not a reality yet,” said Frank Bunger, founder of U.S. aerospace firm Orion Span, one of the companies vying to take travellers out of this world. “But that’s the nature of these things, it sounds crazy until it is normal.”
U.S. multimillionaire Dennis Tito became the world’s first paying space tourist in 2001, travelling to the International Space Station (ISS) aboard a Russian Soyuz rocket for a reported $20 million. A few others have followed. Since then, companies like Boeing, SpaceX and Blue Origin have been working on ways to bring the stars into reach for more people — opening up a new business frontier for would-be space hoteliers.
U.S. space agency NASA announced in June that it plans to allow two private citizens a year to stay at the ISS at a cost of about $35,000 per night for up to a month. The first mission could be as early as 2020.
But the growing movement has raised questions about the adequacy of current space laws, which mainly deal with exploration and keeping space free of weapons, not hotels and holidaymakers.
“It is difficult now to want to do things in space and get a clear answer from space law,” said Christopher Johnson, a space law adviser at the Secure World Foundation, a space advocacy group. “For something as advanced as hotels in space there is no clear guidance.”
1. What does the underlined word “vying” in Para. 3 mean?| A．Promising. | B．Competing. |
| C．Hesitating. | D．Risking. |
| A．To show he was wealthy enough. |
| B．To praise his contribution. |
| C．To tell us he was very brave. |
| D．To emphasize he took the lead. |
| A．By summary. | B．By comparison. |
| C．By listing figures. | D．By giving examples. |
| A．He opposes space travel. |
| B．He is in charge of a space law. |
| C．It’s urgent to make a space law. |
| D．Space hotels are badly needed. |
【推荐3】Sorry to say, our brains naturally start slowing down at the cruelly young age of 30. It used to be thought that this couldn't be helped, but people of any age could train their brains to be faster and, in effect, younger. Our brain is a learning machine. Given the right tools, we can train our brains to act like they did when we were younger. All that is required is dedicated (专注的)practice: exercise for the mind.
Michael Merzenich, a neuroscientist at the University of California, San Francisco, has developed a computer-based training schedule to speed up how the brain processes information, called Brain Fitness Program. Since much of the data we receive comes through speech, the program works with language and hearing to improve both speed and accuracy.
Over the course of your training, the program starts asking you to distinguish sounds (between “dog”and “bog”, for instance) at an increasingly faster rate. It’s a bit like a tennis. instructor, shooting balls at you faster and faster over the course of the summer to keep you challenged. Though you may have started out slow, a month later you’re pretty quick, ” says Merzenich.
The biggest finding in brain research in the last ten years is that the brain at any ag6: is highly adaptable. If you ask your brain to learn, it will learn. And it may speed up in the process.
To keep your brain young, you can do one of a million new activities that challenge and excite you: playing Ping-Pong or contract bridge, doing puzzles, learning a new language or a dance, taking piano lessons, building a model airplane, mastering gardening technique, discovering the secrets of beer-making and, sure, relearning advanced mathematics.
Anything that closely engages your focus and is strongly rewarding will kick your brain into learning mode and will definitely improve it. Give one of these interesting brain exercises airy.
1. Why does the author call our brain a learning machine?| A．It works well at any age. | B．It can be trained to be sharp. |
| C．It helps us acquire knowledge. | D．It can be used to store information. |
| A．To speak a language at high speed. |
| B．To tell apart words that sound similar. |
| C．To receive tennis training with an instructor. |
| D．To list words that have the same meaning. |
| A．It can be faster and faster. | B．It can be slower and slower. |
| C．It's hard to predict. | D．Ifs likely to be hurt. |
| A．To stress the functions of the brain. |
| B．To show different attitudes towards ageing. |
| C．To tell readers how to keep their brain young. |
| D．To advise people to gain pleasure from activities. |
