For some people, choosing to be scared can be fun. Going through a haunted house might make them scream, then laugh! They like to be scared because they like the way their body changes. For others, that feeling takes their mind off their worries. “You’re probably not thinking about your homework that’s due next week when you’re playing a game of hide-and-seek,” says Dr. Margee Kerr, a sociologist (社会学家) from the University of Pittsburgh.

Being scared is not always a treat. When a balloon pops, we may jump. Our heart beats faster and harder, and we breathe faster. That’s because when we meet something we don’t know or something alarming, some reactions are triggered (触发) to help prepare us for the unknown. Once the body is alert (警觉的), the brain decides whether or not the danger is real.

Fear is a tool that the brain uses to keep the body safe. It tells a person to hide, run away, or protect oneself. Faster heartbeat and breathing send more blood and oxygen to the muscles (肌肉) so they’re ready when they’re needed.

Our memories also help protect us. We keep a close eye on babies because they don’t understand what might hurt them. As babies grow, they learn what’s unsafe, and their brains store those memories. Then their brains use fear to warn them of dangers. “We don’t want to be fearless,” Dr. Kerr says. “It’s good to have a healthy sense of what’s dangerous!”

________ Experiences can lead to long-lasting fears that may stop a person from trying new things. We’re born with the ability to feel fear, but what we’re afraid of is learned. A long-lasting fear can mean you’ve had a bad experience and your brain doesn’t want you to have it again. If a dog bit someone, that person might feel afraid of all dogs.

Luckily, many people have beat their own fears. Here’s one way: Instead of listening to their imagination, they learn the facts about anything that seems scary. Knowledge can help a person feel less afraid.

Of all the animals on Earth, none are more willing to explore than humans. Other animals will go in search of food or water. But humans can be encouraged by the possibility of discovery. So what is it that caused us to spread out across the world?

Perhaps it’s in our DNA. In 1999, Dr. Chuansheng Chen carried out a study of a gene (基因) known as DRD4-7R. This gene is found in about 20% of all humans. This kind of people are mostly interested in taking risk, exploring. and getting new ideas. Dr. Chen found that DRD4-7R is more common in people who move around a lot than those who don’t. For example, studies in Africa show that the gene is much more common in nomadic tribes (游牧的部落) than in tribes that prefer to stay in one place. Several other researchers have studied this topic and found out more to support Dr. Chen’s research.

But can a single gene be a drive (驱动) for the need to explore? Dr. Kidd doesn’t think so. He thinks DRD4-7R might make people get more curious, but other important sets of genes also give us great minds and skilled hands. He believes that not just one gene, but groups of genes work together to create behaviors like exploration.

The environment we live in also plays a role in our need to explore. For example, during the European Age of Exploration, explorers became rich and famous for their discoveries. This drove others to try to increase their wealth through exploration. Therefore, their exploration was more likely encouraged by money than by genes.

Maybe the need to explore comes from something inside us, such as the DRD4-7R gene. Or maybe it has more to do with what’s happening in the world around us. Maybe it’s both. Whatever the reason, it seems we (or at least some of us) will keep exploring the mountains, the sea, the stars, and beyond, because that’s just what humans do.

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Do you know there is a connection between music and language? You may not believe it. But recent studies give us the answer: Music can improve certain language abilities in the brain. Now, let's look at two examples.

Recently, researcher Kris has done a research which shows that playing a musical instrument can improve a person's hearing ability. In his study, he divided the people into two groups. The people in the first group were musicians, while those in the other group had no musical training. He asked these people to listen to a person talking in a noisy room. As a result, the musicians were able to hear the talking person more clearly.

You may wonder why. The answer is that musicians can hear better because they learn to pay attention to certain sounds. Think about violinists. When they play with the group, they hear their own instrument and many others’ too. But they must listen closely to what they are playing, and pay no attention to the other sounds. In this way, musicians are able to focus on certain sounds, even in a room with lots of nose.

A doctor at Harvard Medical School works with stroke（中风）patients. These people cannot say their name, addresses or other information normally because of their illness. However, they can still sing. He was surprised to find that singing words helped his patients to speak. Why does this work? The doctor isn’t sure. Music seems to make different parts of the brain work, including the damaged（损坏的）parts. This might help patients to use that part of the brain again.

Music can improve concentration（注意力）, memory, listening skills and overall language abilities. It can even help sick people get better. Playing an instrument or singing can help us do better in school and keep our brain sharp as we get older. Music is not only enjoyable but also good for us in many other ways.