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Directions: Read the following passage. Summarize the main idea and the main points of the passage in no more than 60 words. Use your own words as far as possible.

THE TEENAGE BRAIN

Parents, teachers, and anyone who regularly deals with teenagers knows how difficult the adolescent years can be. Adolescents have always been known to do wild — even dangerous — things. This was thought to be due to the foolishness of youth. Now, brain-imaging technology allows scientists to study the physical development of the brain in more detail than ever before. Their discoveries have led to a new theory of why teens act the way they do.

Recently, scientists discovered that though our brains are almost at their full size by the age of six, they are far from fully developed. Only during adolescence do our brains truly “grow up”. During this time, they go through great changes, like a computer system being upgraded. This “upgrade” was once thought to be finished by about age 12. Now, scientists have concluded that our brains continue to change until age 25. Such changes make us better at balancing our impulses with the need to follow rules. However, a still-developing brain does this clumsily. The result, scientists claim, is the unpredictable behavior seen in teenagers.

The studies confirm that teens are more likely to take risks and behave in extreme ways. Fortunately, the news isn’t all negative. As brain scientist B.J. Casey points out, the teen brain inspires such behavior in order to help teenagers prepare for adult life.

One way the brain does this is by changing the way teens measure risk and reward. Researchers found that when teens think about rewards, their brains release more of the chemicals that create pleasure than an adult brain would. Researchers believe this makes the rewards seem more important than the risks, and makes teens feel the excitement of new experiences more keenly than adults do.

Research into the structure of the teen brain also found that it makes social connections seem especially rewarding. As such, teens have an intense need to meet new people.

Scientists suggest this is because as teens, we begin to realize that our peers may one day control the world we live in. Because it is still developing, a teen brain can change to deal with new situations. It therefore connects social rewards with even more pleasure. In this way, the brain encourages teens to have a wide circle of friends, which is believed to make us more successful in life.

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