It is not only praise or punishment that determines a child's level of confidence. There are some other important ways we shape our kids—particularly by giving instructions and commands in a negative or positive choice of words. For example, we can say to a child “Don't run into traffic!” or “Stay on the footpath close to me.” In using the latter, you will be helping your kids to think and act positively, and to feel competent in a wide range of situations, because they know what to do, and aren't scaring themselves about what not to do.

    Why does such a small thing make a difference? It is all in the way the human mind works. What we think, we automatically rehearse. For example, if someone offered you a million dollars not to think of a blue monkey for two minutes, you wouldn't be able to do it. When a child is told “Don't fall off the tree,” he will think of two things: “don't” and “fall off the tree”. That is, he will automatically create the picture of falling off the tree in his mind. A child who is vividly imagining falling off the tree is much more likely to fall off. So it is far better to use “Hold on to the tree carefully.”

    Clear, positive instructions help kids to understand the right way to do things. Kids do not always know how to be safe, or how to react to the warning of the danger in negative words. So parents should make their commands positive. “Sam, hold on firm to the side of the boat” is much more useful than “Don't you dare to fall out of the boat?” or worse still “How do you think I'll feel if you drown?” The changes are small but difference is obvious.

    Children learn how to guide and organize themselves from the way we guide them with our words, so it pays to be positive.

Decision-making under Stress

    A new review based on a research shows that acute stress affects the way the brain considers the advantages and disadvantages, causing it to focus on pleasure and ignore the possible negative (负面的) consequences of a decision.

     The research suggests that stress may change the way people make choices in predictable ways.

    “Stress affects how people learn,” says Professor Mara Mather. “People learn better about positive than negative outcomes under stress.”

    For example, two recent studies looked at how people learned to connect images(影像) with either rewards or punishments. In one experiment, some of the participants were first stressed by having to give a speech and do difficult math problems in front of an audience; in the other, some were stressed by having to keep their hands in ice water. In both cases, the stressed participants remembered the rewarded material more accurately and the punished material less accurately than those who hadn't gone through the stress.

    This phenomenon is likely not surprising to anyone who has tried to resist eating cookies or smoking a cigarette while under stress –at those moments, only the pleasure associated with such activities comes to mind. But the findings further suggest that stress may bring about a double effect. Not only are rewarding experiences remembered better, but negative consequences are also easily recalled.

    The research also found that stress appears to affect decision-making differently in men and women. While both men and women tend to focus on rewards and less on consequences under stress, their responses to risk turn out to be different.

    Men who had been stressed by the cold-water task tended to take more risks in the experiment while women responded in the opposite way. In stressful situations in which risk-taking can pay off big, men may tend to do better, when caution weighs more, however, women will win.

    This tendency to slow down and become more cautious when decisions are risky might also help explain why women are less likely to become addicted than men: they may more often avoid making the risky choices that eventually harden into addiction.

Training the Brain

    People who can accomplish unbelievable tasks, such as memorizing thousands of random numbers in under an hour, state that they just have normal brains. Some memory superstars compete in Olympic-like World Memory Championships. These mental athletes, or MAs for short, can memorize names of dozens of strangers in a few minutes or any poem handed them. Ed Cooke, a 24-year-old MA, explains they see themselves as participants rescuing the long-lost art of memory training. These techniques existed not to recall useless information, but to cut into the brain basic text and ideas.

    A study in the journal Nature examined eight people who finished near the top of the World Memory Championships. The scientists examined whether their brains were fundamentally different from everyone else's or whether they were simply making better use of memorizing abilities we all possess. They put the MAs and control subjects into brain scanners and had them memorize numbers and photographs. The result surprised everyone. The brains of the MAs and those of the control subjects were indistinguishable. On every test, the MAs scored in the normal range. However, when the scientists examined what part of the brain was used during a memory activity, they found the MAs relied more heavily on areas in the brain involved in spatial memory.

    MAs offer an explanation: anything can be fixed upon our memories and kept in order by constructing a building in the imagination and filling it with pictures of what needs to be recalled. Dating back to the fifth century, the building is called a memory palace. Even as late as the fourteenth century, when there were copies of any text, scholars needed to remember what was read to them. Reading to remember requires a different technique than speed reading. If something is made memorable, it has to be repeated. Until relatively recently, people read only a few books intensively (细致地) again and again, usually aloud. Today we read extensively, usually only once and without continuous focus.

    So the great difference is the ability to create impressive pictures in mind and to do it quickly. Using memory palaces, MAs create memorized pictures. For example, recombine the pictures to form unforgettable scenes such as the ways through a town. One competitor used his own body parts to help him memorize a 57,000-word dictionary.

    Anyone who wishes to train the mind needs first to create fantastical palaces in the imagination. Then they should cut each building into cubbyholes for memories. In a short amount of time, they will notice improvement with remembering things. To keep the skill sharp, MAs deliberately empty their palaces after competitions, so they can reuse them and they recommend that beginners do the same.

    I'm sitting in my kitchen in London, trying to figure out a text message from my brother. He lives in our home country of Germany. We speak German to each other, a language that's rich in odd words, but I've never heard this one before: fremdschämen. I'm too proud to ask him what it means. I know that eventually, I'll get it. Still, it's slightly painful to realize that after years of living abroad, my mother tongue can sometimes feel foreign.

    Most long-term migrants know what it's like to be a slightly rusty(生疏的) native speaker. The process seems obvious: the longer you are away, the more your language suffers. But it's not quite so straightforward.

    In fact, the science of why, when and how we lose our own language is complex and often different to what we think. It turns out that how long you've been away doesn't always matter. Socializing with other native speakers abroad can worsen your own native skills. And emotional factors like trauma(精神创伤) can be the biggest factor of all.

    It's not just long-term migrants who are affected, but to some extent anyone who picks up a second language. The minute you start learning another language, the two systems start to compete with each other, says Monika Schmid, a linguist at the University of Essex.

    Schmid is a leading researcher of language attrition, a growing field of research that looks at what makes us lose our mother tongue. In children, the phenomenon is somewhat easier to explain since their brains are generally more flexible and adaptable. Until the age of about 12, a person's language skills are relatively easy to change. Studies on international adoptees have found that even nine-year-olds can almost completely forget their first language when they are removed from their country of birth.

    But in adults, the first language is unlikely to disappear entirely except in extreme circumstances. For example, Schmid analyzed the German of elderly German-Jewish wartime refugees(难民) in the UK and the US. The main factor that influenced their language skills wasn't how long they had been abroad or how old they were when they left. It was how much trauma they had experienced as victims. Those who left Germany in the early days of Nazi occupation, before the worst violence, tended to speak better German – despite having been abroad the longest. Those who left later, tended to speak German with difficulty or not at all.

    "It seemed very clearly a result of this trauma", says Schmid. "Even though German was the language of childhood, home and family, it was also the language of painful memories." The most traumatised refugees had held them back. As one of them said: I feel that Germany betrayed me. America is my country, and English is my language.

Both humans and animals have enemies. 11 is easy for us to know the difference between our friends and our enemies. But can other animals do the same? Elephants can! They can use their sense of vision and smell to tell the difference between people who mean a threat and those who do not. In Kenya, researchers find that elephants react differently to clothing worn by men of the Maasai and Kamba ethnic groups. Young Maasai men hunt animals and thus mean a threat to elephants; Kamba men are mainly farmers and are not a danger to elephants.

In an experiment conducted by animal scientists, elephants were first presented with clean clothing or clothing that had been worn for five days by either a Maasai or a Kamba man. When the elephants noticed the smell of clothing worn by a Maasai man, they moved away from the smell faster and took longer to relax than when they noticed the smells of either clean clothing or clothing worn by a Kamba man.

Clothing color also plays a role. In the same study, when the elephants saw red clothing not worn before, they reacted angrily, as red is typically worn by Maasai men. Rather than running away as they did with the smell, the elephants acted angrily toward the red clothing.

The researchers believe that the elephants' emotional reactions arc due to their different senses of smell and sight. Smelling a possible danger means that a threat is nearby and the best thing to do is run away and hide. Seeing a potential threat without its smell means that risk is low. Therefore, instead of showing fear and running away, the elephants express their anger and become aggressive.

    One day after school, Bill walked past the shop on the street corner as usual. He stopped to look at the front row of shoes, and he felt sorry for himself.

    He really wanted to have a new pair for his birthday. He sadly walked away and

    thought of how to tell his mother. He knew she would give him anything if she could. But he also knew she had little money. He decided not to go home at once, because he looked worried and he didn't want his mother to worry about him. So he went to the park and sat on the grass. Then he saw a girl in a wheelchair. He found that the girl moved the wheels with her hands. Bill looked at her carefully and was surprised to see that the girl had no feet.

    He looked down at his own feet. "It was much better to be without shoes than without feet," he thought. It was not right for him to feel so sorry and sad. He went away and smiled, thinking he was luckier in life.