A report says older adults who test their minds with increasingly difficult projects have better mental ability than those who do less demanding activities.

    To keep our brains sharp as we age, we are often told to keep our minds active. As the old saying goes, “Use it or lose it.” But, there is very little scientific evidence to support than.

Denise Park is head of the university's Center for ? Vital Longevity. She designed a study in which she and her tern placed 221 healthy aging and older adults into one of three groups.

    “We asked people to learn new things, like quilting or photography. We asked other people to just do fun things like being in a social group function but were not likely to have a very large effect.”

    The subjects took part in their assigned activities for 15 hours a week over three months. At the end of that time, the researchers found that the adults who learned new skills, such as digital photography, showed the greatest improvements on memory tests.

    No improvements were seen in the results of those in the social group that did activities together like going on field trips. There were also no improvements among the third group that listened to classical music or did crossword puzzles.

    Denise Park believes one reason for improved memory in the active learning group is that its members were being pushed to learn new skills. The other groups took part in what she call receptive activities. Learning new skills may not cure age-related mental decline. But, Ms. Park thinks being mentally active slows down the process.

Denise Park says the latest information shows that the improvements lasted for at least a year. She and her team plan to do longer follow-up studies with all three groups. She also is interested in learning whether taking part in demanding mental activities delays the development of conditions like Alzheimer's disease.

    Jolly Joe always arrived at my neighborhood at exactly half past noon. The clang (叮当声) of the bell on his red and black truck was then the sweetest sound in the world. Brightly colored stickers advertising his amazing kinds of treats could be found on all sides of his truck. The whole neighborhood would magically come to life.

    Holding a nickel (五分镍币), I'd run to the back of the vehicle, where children were already gathering. Jolly Joe would jump out of his truck, the sun shining on his hair. He was an older man, short and round, with a pleasant face and a welcoming smile.

    I don't know how, but he knew us all by name, as well as which treats we preferred. My favorite was the Buried Treasure. By eating all the ice cream, you'd discover the treasure inside: a lion, a dog or even a funny clown — printed onto a plastic stick.

    When it was finally my turn, he'd put his arm deep inside one of the boxes, and pause (停顿) for a moment, a puzzled look crossing his face. Then, suddenly, he'd pull it out: the Buried Treasure! I couldn't wait to enjoy the cool, sweet ice cream.

    As quickly as he arrived, it was time for Jolly Joe to go, leaving behind laughing, excited children with sticky hands and faces. Soon the sound of his clanging bell would slowly disappear in the distance.

    I always hated to see Jolly Joe go, because I knew the rest of the day would be as hot and boring as before. But I took some comfort in knowing that the next day he'd come round the corner at half past noon and once again spread his magic.

    As years went by, I realized that one of the biggest problems of these adults are worry. A large majority of students were businessmen, executives, salesmen, engineers, accountants: a cross section of all the trades and professions—and most of them had problems! There were women in the classes — businesswomen and housewives. They, too, had problems! Clearly, what I needed was a textbook on how to conquer worry—so again I tried to find one.

    I went to New York's great public library at Fifth Avenue and Forty-second Street and discovered to my astonishment that this library had only twenty-two books listed under the title WORRY. I also noticed, to my amusement, that it had one hundred and eighty-nine books listed under WORMS. Almost nine times as many books about worms as about worry! Surprising, isn't it? Since worry is one of the biggest problems facing mankind, you would think, wouldn't you, that every high school and college would give a course on "How to Stop Worrying"?

    Yet, if there is even one course on that subject in any college in the land, I have never heard of it. No wonder David Seabury said in his book How to Worry Successfully: " We grow up with as little preparation for the pressures of experience as a bookworm asked to do a ballet (芭蕾舞)."

    The result? More than half of our hospital beds are occupied by people with nervous and emotional troubles.

    I looked over those twenty-two books on worry, reposing (靠) on the shelves of the New York Public Library. In addition, I purchased all the books on worry I could find; yet I couldn't discover even one that I could use as a textbook in my course for adults. So I decided to write one by myself.

    Every morning my father buys a newspaper on his way to work. Every evening my mother looks through magazines at home. And every night, I look at the posters with photos of David Beckham and Yao Ming on my bedroom wall before I go to sleep. Can we imagine life without paper or print?

    Paper was first created about 2,000 years ago, and has been made from silk, cotton, bamboo, and, since the 19th century, from wood. People learned to write words on paper to make a book. But in those days, books could only be produced one at a time by hand. As a result, they were expensive and rare. And because there weren't many books, few people learned to read.

    Then printing was invented in China. When printing was developed greatly at the beginning of the 11th century, books could be produced more quickly and cheaply. As a result, more people learned to read. After that, knowledge and ideas spread quickly.

    Today information can be received online, downloaded from the Internet rather than found in books, and information can be kept on CD-ROMs or machines such as MP3 players.

    Computers are already used in classrooms, and newspapers and magazines can already be read online. So will books be replaced by computers one day? No, I don't think the Yao Ming poster on my bedroom wall will ever be replaced by a computer two metres high!

    The phone ID flashed，“Emergency Vet”.“ Oh no” I whispered. I could not lose Merlin now.

    Ron and I had tried to have children for a long time with depressing results. I threw myself into my work. Any maternal feelings I had were spent on Merlin.

    I couldn't wait to get home from work each night. I wanted to pick up that warm bundle of loving fur and nestle him. I wanted to sing “Rock-a-bye Merlin”，as I did every night as he would put his paws around my neck.

    Merlin was my comfort especially at times when I wondered if God was listening. But last night something had changed. Not only did I sing “Rock-a-Bye M1erlin”,but I asked, you 're gone？”

    Although Merlin was 19 years old, a senior in the· age of a cat, he didn't look or act that way. I didn't want to accept the fact that he was nearing the end of his lifetime. My job at the law firm was so demanding and stressful that I couldn't imagine getting through the day without Merlin waiting to greet me at home.

    I dialed the vet's number. I asked for my husband but he already left. Then I took a breath and asked the question that no one wants to ask，“Is my Merlin still alive？”The nurse said“ yes.”

    Ron came home and said that Merlin had almost no red blood cells left. White blood cells were replacing them. Merlin would need expensive transfusions most likely on a monthly basis. We both knew Merlin was running out of time. I asked Ron to drive me to the vet so I could say goodbye to my little boy cat but he was beat tired and it was late. Ron said if Merlin was still alive he next morning then he would take me to the vet.

    The next morning I called the vet. Merlin had survived the night. After driving to the vet, I went into the examining room. The nurse brought Merlin and placed him on an examining table on his side. His eyes were tightly shut. I thought he died already. I carefully edged my hand to reach his body. His body felt warm, but when I spoke his name there was no response. No response to his name or that I was there and that I loved him. I was extremely sad. In that examining room I felt helpless. I wondered how many people in an examining room felt as helpless as I did. Feeling driven to prayer I yelled, “God this isn't good enough. I need to see my Merlin the way I remember him, I need a miracle and I need it now！”

    At that moment, God granted a miracle. Merlin's favorite compliment entered my mind. I said, “Merlin, you are beautiful and you are gorgeous, do you hear me？”

One eye opened.

    I said “Gotcha”. I kept repeating those words.

    Merlin opened the other eye and, one limb at a time, got up. He was waiting for that phrase. He wanted to hear that he was beautiful and gorgeous again.

    Then I experienced another miracle.

    There was no sound in that examining room until Merlin started walking to me. From out of nowhere, or maybe from heaven, I clearly heard a song we sung in church often: “It Is Well With My Soul.” I remember叫thinking，“Yes, it is well with my soul. I got to see my little boy cat one more time.”

    Merlin walked to me. He put his face in mine, which he had never done before. He rubbed a circle around my face twice. Merlin said goodbye with his face and marked me for life.

    Ron appeared shocked that Merlin was up and had walked to me. I said to Merlin，“Tell God you are a good boy and how much we love you”and then handed him back to the nurse.

    Tears of gratitude poured forth in memory of a miracle. You see for nineteen years God spoke to me through a special cat named granted a miracle. That miracle gave me time to say goodbye.

    After a morning hike in the Saneum HealingForest, 46-year-old firefighter Kang Byoung-wook has tea made from the bark of an elm tree, practices yoga (瑜伽), and makes a picture with dried flowers. He is one of 40 firefighters taking part in a three-day program, the aim of which is to offer "forest healing" (森林治愈); the firefighters all have posttraumatic stress disorder (创伤后应激障碍).

    Saneum is one of three official healing forests in South Korea. Soon there will be 34 more. South Koreans-many of whom suffer from work stress, digital addiction, and great academic pressure have accepted the medicalization of nature with great enthusiasm.

    There is increasing evidence that being outside in a pleasant natural environment is good for us. But how many of us get to enjoy nature regularly? Fewer and fewer, it seems. According to Lisa Nisbet, a psychology professor at Canada s Trent University, evidence for the benefits of nature is pouring in at a time when we are most disconnected from it.

    "We don't think of being outdoors as a way to increase happiness," says Nisbet. "We think other things will, like shopping or TV." But South Korea is starting to challenge this opinion.

    So what are some of the benefits of nature that Nisbet refers to? Being surrounded by nature has one obvious effect: It calms us and reduces our stress levels. This has been shown to lower blood pressure and heart rates.

    Another experiment conducted by psychologist Stephen Kaplan found that people who took a 50-minute walk in a park had better attention and short-term memory than those who took a walk along a city street.

    Perhaps what's more surprising is that nature may also make us more creative. David Strayer, a psychologist at the University of Utah, showed as much with a group of participants, who performed 50 percent better on creative problem-solving tasks after three days of wilderness backpacking.

    In fact, we may never know exactly what nature does to the brain. Something mysterious will always remain, and maybe that's as it should be.