How does our brain know that “this” follows “that”? The sequencing of events that takes place in our head — with one thing coming after another — may have something to do with so-called time cells recently discovered in the human hippocampus (海马结构).
A team led by Leila Reddy, a neuroscience researcher at the French National Center for Scientific Research, sought to understand how human neurons (神经元) in the hippocampus represent time information during a series of learning steps to uncover the functioning of time cells in the brain.
In the first experiment, the study participants were firstly presented with a sequence of five to seven pictures of different people or scenes in a predetermined order that was repeated multiple times. The researchers discovered that, over the course of 60 repetitions of the entire sequence, all of the time-sensitive neurons were stimulated at specific moments in intervals between quizzes, no matter which image was shown.
A second experiment followed the same design, except that, after the sequence was repeated for a fixed number of times, a black screen was shown for 10 seconds, a gap interval that was intended to act as a distraction. The participants were quizzed about the order of the images in the sequence while the electrical activity from individual cells in their brain was recorded. Some neurons were fired at one moment, corresponding to a particular image. Others did so at another moment for a different image. Time cells corresponding to a specific image still switched on during the 10-second gaps in which no image was shown. These gaps appeared to help subjects remember more pictures and their correct order. During the gap periods, about 27 percent of the time cells were activated.
“The activity of these cells is present throughout the trial, providing a timestamp for an event.” Yet the fact that these cells also represent the content of our memory (the “what” as well as the “when”) makes things more complex, a co-researcher Matthew Self explains. “We don’t fully understand how the memory is encoded,” he says, “but the activity pattern across the hippocampus appears to provide us with both the timestamp and the contents of the experience at the same time.”
1. Why did Reddy’s team study time cells in the human hippocampus?| A．To reveal how time cells work. | B．To figure out the function of neurons. |
| C．To understand the structure of time cells. | D．To evaluate the accuracy of time information. |
| A．Arranged. | B．Shot. | C．Replaced. | D．Excited. |
| A．The gaps played a role in subjects’ memory. |
| B．All neurons were active throughout the intervals. |
| C．The pictures were shown to the subjects randomly. |
| D．Time cells switched off with no images being presented. |
| A．It gives us an idea of how memories are encoded. |
| B．It can give us the order and the contents of memory. |
| C．It has the potential to make the brain more complex. |
| D．It may present not only the event order but also the time period. |
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【推荐1】Scientists say they have found out a chemical produced by locusts（蝗虫）that causes the insects to join together in huge swarms（群）.
On their own, locusts are mostly harmless. But in large swarms, they can be extremely destructive. The new finding could lead to new methods to prevent locusts from joining swarms to destroy huge areas of crops.
A recent study published in Nature identifies a pheromone believed to be responsible for the insect’s swarming behavior. A pheromone is a chemical item produced by an animal that influences the behavior of another animal of the same kind.
The pheromone, known as 4VA, was found in the world’s most widespread kind of locust, the migratory locust. It powerfully drew locusts of both sexes and all ages, the research found. And it was produced when as few as four to five locusts came together.
Lead researcher Le Kang is with the Chinese Academy of Sciences’ Institute of Zoology. He told Reuters news agency that migratory locusts are so widespread and dangerous, they represent"a serious threat to agriculture worldwide. " Kang said further research will be needed to find out if 4VA exists in other species, such as the desert locust.
Kang said a chemical could be developed to block 4VA’s effects to prevent swarming. A man-made version of the pheromone might also be developed to attract locusts into traps to be killed. Locusts could also be developed with genetic changes that would not react to 4VA, Kang added. Such locusts could be sent to the wild to build wild non-swarming populations.
Leslie Vosshall, head of Rockefeller University’s Laboratory of Neurogenetics and Behavior in New York, said one of the most exciting developments would be finding a chemical that could block the reception of 4VA. She noted that there are still several unknowns about the research. These include whether 4VA is the only cause of swarm formation, and whether other locust species respond similarly to the chemical.
1. What is the new finding of the study?| A．New methods could be used to stop locusts. |
| B．Locusts do not cause much damage on their own. |
| C．A large number of locusts can destroy the crops terribly. |
| D．Locusts swarm because of a chemical produced by themselves. |
| A．It only exists in the migratory locust. | B．It is made at least in groups of forty. |
| C．It is to blame for the locust’s swarming. | D．It affects the behavior of other animals. |
| A．Pessimistic. | B．Optimistic. | C．Subjective. | D．Objective. |
| A．Can we kill locusts? | B．How do locusts destroy crops? |
| C．How do locusts get swarmed? | D．Can we control the locust’s damaging? |
【推荐2】Can you trust your very first childhood memories? Maybe not, a new study suggests.
Past researches show that people's earliest memories typically form around 3 to 3. 5 years of age. But in a recent survey of more than 6,600 people, British scientists have found that 39 percent of participants claimed to have memories from age 2 or younger. These first memories are likely false, the researchers said. This was particularly the case for middle -aged and older adults.
For the study, researchers asked participants to describe their first memory and the age at which it occurred. Participants were told they had to be sure the memory was the one that had happened. For example, it shouldn't be based on a photograph, a family story or any source other than direct experiences. Then the researchers examined the content, language and descriptive details of these earliest memories and worked out the likely reasons why people would claim to have memories from an age when memories cannot form.
As many of these memories dated before the age of 2, this suggests they were not based on actual facts, but facts or knowledge about their babyhood or childhood from photographs or family stories. Often these false memories are fired by a part of an early experience, such as family relationships or feeling sad, the researchers explained.
"We suggest that what a rememberer has in mind when recalling fictional early memories is …a mental representation consisting of remembered pieces of early experiences and some facts or knowledge about their own babyhood or childhood, " study author Shania Kantar said in a journal news release, "Additionally, further details may be unconsciously inferred or added. Such memory-like mental representations come~ over time, to be collectively experienced when they come to mind, so for the individual, they quite simply are memories, which particularly point to babyhood. "
"Importantly, the person remembering them doesn't know this is fictional," study co-author Martin Conway said "In fact, when people are told that their memories are false they often don't believe it. "
1. What can we learn from a recent study?| A．Memories form after the age of 3. | B．Participants are good at telling stories |
| C．Adults are likely to form false memories | D．Earliest memories may play a trick on us |
| A．A direct experience. | B．A family story. |
| C．A family photo. | D．A sad feeling. |
| A．They are repeated mental representations. |
| B．They are a collection of early experiences. |
| C．They are a combination of both facts and fictions. |
| D．They are further details of remembered experiences. |
| A．Society. | B．Psychology. | C．Technology. | D．Health. |
【推荐3】“The apple doesn’t fall far from the tree.” When it comes to device addiction, this may very well be the case. If you believe that how you engage with your smartphone has no impact on your children, think again.
One study looked at 200 families and noted that the children of parents with phone addictions were much more likely to have behavior issues. In short, this obsession led to “technoference” or interruption of everyday interactions between parents and kids. In some cases, this interruption happened in face-to-face conversations, and in other cases, the devices disrupted playtime or meals. When this type of “technoference” occurred, parents rated their children as displaying more behavior problems, including whining, losing temper, sulking (生闷气), and becoming frustrated.
In addition, according to children development experts, there are bilateral (双边的) signaling systems that occur between adults and children, aiding the construction of the basic architecture of the brain. For example, infants and toddlers are highly engaged with the vocal cues of their parents that tend to happen with simplified grammar, a high-pitched tone, and exaggerated enthusiasm. This mode of relational conversation is incredibly important to a child’s development.
With the arrival of smartphones, many parents are distracted and stuck in what experts are calling “continuous partial attention” mode. This leads to significant and recurring disruptions to the parent-child conversation flow, which can impair not only a child’s language learning ability but also their school achievements overall.
While your habit may seem harmless, your kids may actually be imitating your behavior and forming a dependence of their own. One study reported that some teenagers may spend up to 12 hours — half of an entire day — online and mindlessly swiping through social media apps without engaging in any one piece of content beyond a few seconds.
As a parent, the best thing you can do is lead by example. Try to limit time spent with technology, especially when it diverts (牵制) your attention from other priorities. Shut down smartphones at dinner. Set aside phone-free time each day to engage with your children without the distraction that technology brings. While you may not be able to completely cut ties with new modes of communication, you can be sure that your children get the one-on-one time they need to develop into healthy, happy adults.
1. Which is TRUE according to the studies in the passage?| A．Parents rate their children’s behavior at parent-children time interruptions. |
| B．Children’s poor school achievements are due to their addiction to social media. |
| C．The more engagement of parents, the better development of speech in children. |
| D．Children imitate parents’ behavior but form their own harmless habits. |
| A．To further scientifically explain a child’s behavioral problem. |
| B．To give an argument for the problem of a child’s language learning ability. |
| C．To support the argument for a child’s addiction to devices. |
| D．To present background information for the topic of the passage. |
| A．Disrespectful. | B．Apologetic. |
| C．Negative. | D．Friendly. |
| A．To stress children will follow parents’ example. |
| B．To provide evidence of device addiction. |
| C．To show the close bond between parent and children. |
| D．To highlight the final solution to device addiction. |
【推荐1】Cars and taxis passed the eighty-four pink granite columns that stood like guards at the front of the station. Pedestrians approached along an elegant arched passageway. The waiting room was fifteen stories high and a block and a half long. In many ways, Pennsylvania Station, also known as Penn Station, was the heart of New York City.
Built in 1910, the station was an energetic place. Filled with bustling crowds, Penn Station welcomed travelers with its bright and hearty atmosphere. Getting on or off a train here was an exciting thing to do.
By the 1950s, however, fewer people were travelling by train. They had found alternate ways to travel. Airlines carried more and more passengers. New superhighways made driving long distances easier.
By the end of the decade, the owners of Penn Station made a fateful decision. They would demolish the famous landmark. In its place, they would build an office building and a sports arena. The plan seemed to make financial sense, but little thought was given to train passengers. People would now have to board trains underground from small waiting areas near the train tunnels.
Demolish Penn Station? When New Yorkers heard the plan, they couldn’t believe their ears. One of the city’s finest public places had been given a death sentence, and New Yorkers didn’t like the verdict!
Citizens joined together to save the landmark. For months, they would strive to rescue it from the wrecking ball. They pointed out that the station was an architectural treasure. It had played a key role in the life and history of the city. What’s more, the new underground station would be cramped and uncomfortable. A person didn’t have to be very observant to see that.
Unfortunately, no one could stop the tragedy. City officials enforced the wishes of the owners, and in 1963, the wrecking balls went to work. Onlookers gazed in horror as an architectural masterpiece crashed to the ground in dust.
In the end, New Yorkers resigned themselves to the loss of Penn Station. They had, however, learned a lesson: Landmark buildings had to be saved. A special landmarks commission was formed. Its primary purpose was to identify and protect the city’s finest architecture. Its members recognized that as a city changes and matures, some older buildings do have to be demolished to make room for new ones. Landmarks, however, must be preserved.
Ironically, by the 1990s, train travel had picked up at Penn Station, especially among commuters from surrounding towns. The underground station had difficulty handling the raging river of traffic. As predicted, few liked the cramped replacement.
Some New Yorkers hope to convert a grand old post office into a new train station. The post office is in the right place, and in some ways, it resembles the old Pennsylvania Station. The plan may work, but the major repair will be a very difficult and costly feat. So the tragedy teaches another lesson: Sometimes, it’s better to preserve what we have than to try to replace it.
1. Which of the following accounts for the disappearance of the Penn Station?| A．Economic consideration. | B．Renewed enthusiasm for sports. |
| C．The outdated design of the station. | D．Better underground facilities. |
| A．The New Yorkers cheered at the sight of the crash of the station. |
| B．The members realized that all the old buildings should be preserved. |
| C．It was too late for the city to mend the mistake. |
| D．The replacement of the station was never a problem. |
| A．scenery | B．banquet | C．probability | D．achievement |
| A．How was the Pennsylvania Station built? |
| B．What happened to the Pennsylvania Station? |
| C．Where should the Pennsylvania Station be built? |
| D．Why should the Pennsylvania Station be recovered? |
【推荐2】Limiting your child’s candy this Halloween might be more of a trick than a treat, experts say. Once you’re a grown-up raising kids, that bag full of candy might be the scariest part of Halloween — whether it’s concern about a potential sugar rush, worries of parenting perfectionism or diet culture anxiety.
“It makes sense to be scared, because we’ve been taught to be scared,” said Oona Hanson, a parent coach based in Los Angeles. “Sugar is sort of the boogeyman in our current cultural conversation.”
But micromanaging your child’s candy supply can backfire (适得其反)，leading to an overvaluing of sweets，binge (暴食) behavior or unhealthy restriction in your child，said Natalie Mokari, a registered dietitian-nutritionist in Charlotte, North Carolina.
As stressful as it may be to see your child faced with more candy in one night than they would eat in an entire year, the best approach may be to lean into the joy, she added. “They are only in that age where they want to trick or treat for just a small glimpse of time — it’s so short-lived,” Mokari said. “Let them enjoy that day.”
Experts aren’t suggesting kids have sugar all day every day. The American Heart Association and the 2020 Dietary Guidelines Advisory Committee — groups charged with providing science-based recommendations every live years — have recommended lower daily levels of sugar. Too much added sugar has been associated with cardiovascular disease and lack of essential nutrients.
But a healthy relationship with food has balance, and you can keep your kids’ diets full of nutrients while allowing them lo eat sweets, Mokari said.
1. Why are the grown-ups raising kids scared at Halloween?| A．Because they don’t look perfect enough. |
| B．Because their children faced too much candy. |
| C．Because they’ve been taught to be. |
| D．Because they don’t know the diet culture. |
| A．Sugar can make us scared. |
| B．Sugar is a sort of healthy food. |
| C．Sugar is harmful to our health. |
| D．Sugar is a sort of essential nutrient. |
| A．Kids should have sugar all day every day. |
| B．It makes sense to be scared with that bag full of candy. |
| C．It’s a good idea to micromanage your child’s candy supply. |
| D．Kids would have much joy when treated to candy at Halloween. |
| A．Diseases associated with sugar. |
| B．The right attitude towards sugar. |
| C．Allowing your kids to eat sweets. |
| D．Keeping your kids’ diets full of nutrients. |
【推荐3】For generations, the standard way to learn how to ride a bicycle was with training wheels. But in recent years, many parents prefer to train their kids with balance bikes, two-wheelers that enable children to develop the competence needed for bicycling.
Given the benefits of balance bikes, why did it take so long for them to replace training wheels? There are plenty of other examples in which ignored solutions that involve subtraction(减法) turn out to be better alternatives. In some European cities, for example, urban planners have gotten rid of traffic lights and road signs to make streets safer.
Leidy Klotz, an engineer at the University of Virginia, noticed that reformative designs, in which elements are removed from an existing model, were uncommon. So he reached out to Adams, a social psychologist, to try to figure out why this was the case. The two researchers hypothesized(假设) that there might be an explanation: when faced with a problem, people tend to select solutions that involve adding new elements rather than taking existing components away.
Adams, Klotz and their colleagues set out to test if their hypothesis was correct. The researchers first carried out a set of studies. In one, they asked 91 participants to make a pattern symmetrical(对称的) by either adding or removing colored boxes. Only 18 people used subtraction. In another, the team scanned through ideas for improvement submitted to an incoming university president and found that only 11 percent of 651 project plans involved getting rid of an existing regulation, practice or program.
These findings suggest that “additive solutions have sort of a priority”, says Benjamin Converse, a co-author of the study. “Subtractive solutions are not necessarily harder to consider, but they take more effort to find.”
For now the team hopes that these findings will encourage people across various fields to think about subtractive options that might be typically ignored. “The hope is that, just by getting people to think about this more, maybe it will help inspire some other ignored subtractions,” Converse says.
1. What is the purpose of paragraph 1?| A．To present a problem. | B．To introduce the topic. |
| C．To give some examples. | D．To put forward a concept. |
| A．Balance bikes are not good for training kids. |
| B．People used to learn riding bikes effortlessly. |
| C．Parents now train kids to ride bikes pointedly. |
| D．Some European cities ignore their governance. |
| A．They are superior to additive solutions. |
| B．They are often harmful for creativity. |
| C．They are always overlooked by our brain. |
| D．They are often preferred by conservatives. |
| A．A New Way of Management |
| B．A Trend of Avoiding Regulations |
| C．A New Concept of Problem-solving |
| D．A Study on Problem–solving Methods |
