不久前，神经科学家们都相信这样一种观点，即随着岁月的流逝，人类大脑会逐渐退化，而且人类对此无能为力。

    但是，在脑部成像技术的辅助下，最近的大量研究都得出了截然不同的结论。在我们一生当中，灰色神经组织会不断再生，形成新的活性细胞。市场研究公司SharpBrains创始人兼CEO阿尔瓦罗•费尔南德斯说：“人类的大脑就像是一个充满生机、不断生长的茂密森林，里面有数十亿个神经细胞和神经节。”

    神经可塑性学科是一门新兴学科，研究大脑如何变化和调整。该学科发现，与肌肉一样，大脑的情况也属于“非用即失”。他补充说：“当大脑中出现新的神经细胞后，它们所在的位置和存活时间，都取决于你如何利用它们。”

    费尔南德斯是《大脑健康指南》（The SharpBrains Guide to Brain Fitness）一书的联合作者。这本书将目前在这一领域的大量研究成果总结成了具体的建议，指导读者如何从现在做起，预防老年痴呆和未来可能出现的其他认知功能障碍。

    机缘巧合的是，有利于大脑健康的做法和加快职业发展的措施之间有许多相通之处。比如下面五条建议：

1. 学无止境。最新研究发现，一个人的受教育程度越高，患老年性智力衰退的几率越低。费尔南德斯发现：“接受过高等教育的人更有可能从事刺激智力的工作，”而这将促进新神经细胞的生成。如果在职业生涯当中养成不断学习新技能的习惯，它将不仅有利于你的大脑健康，而且还可以提高自身的价值，使你拥有更加广阔的发展前景。

2. 沉浸式体验另外一种文化。尤其是学习一门外语。随着美国公司（尤其是市场营销）比以往更加双语化，学习西班牙语是明智的选择——当然，要想进行真正的头脑训练，可以学习俄语、汉语或阿拉伯语。因为这几种语言的字母不同，进一步提高了它的挑战性。

    如果有条件，也可以申请海外任职。这不仅可以丰富个人的履历，提高身价，而且费尔南德斯认为，与留在国内相比，“探索和适应新的地方会迫使人们更加关注周围的环境”。探索一种陌生的文化，即便时间很短，也无异于给你的大脑来了一节软体健美操。

3. 尝试有难度的“延伸性”任务。费尔南德斯写道：“目的是要尝试新鲜事物，提高挑战的难度，所以任务肯定不能太简单，也不能太常见。”他还表示，这意味着“花费精力，走出自己的舒适区。”多样性与挑战一样重要，最近许多研究均显示：“过度专业化并非保持长期大脑健康的最佳策略。一名证券交易商可能希望尝试一项艺术活动，以此来刺激自己很少用到的脑细胞。”

4. 管理压力。费尔南德斯说：“不论压力源自外部事件还是自己内心的想法，过多的压力都会杀死神经细胞，而且会阻止新细胞的形成。”很明显，这不是我们想看到的庆幸。《大脑健康指南》一书详细介绍了如何通过体育锻炼、冥想甚至开怀大笑来保护大脑免受过多压力的破坏。此外，这些措施还可以防止职业倦怠。隔一段时间真正休一次假也被证明是缓解压力的有效方法。

5. 广交朋友。有许多不同的好友，不仅会在你想换工作（或招聘合适人选）时变成巨大的优势，而且费尔南德斯写道，事实证明，“社交参与有利于大脑健康。”新研究发现，定期与其他人互动有利于“提高短期绩效，以及增强认知储备。”到底有多少好朋友才是理想状态？人类大脑皮层似乎只能处理有限数量的关系，这个数量（神经科学家们以发现者的名字命名，称其为邓巴数量）就是150。有趣的是，费尔南德斯发现，虽然许多人在Facebook上有数千好友，“但标准数量约为120个，这与邓巴数量基本一致——也就是人们在真实生活中的朋友和熟人数量。”（财富中文网）

    译者：刘进龙/汪皓

    Not so long ago, conventional wisdom among neuroscientists held that the human brain was doomed to deteriorate with the passage of time, and there wasn't much anyone could do about it.

    Instead, a raft of recent studies, aided by brain-imaging technology, all point to a much different conclusion: Our grey matter can keep on regenerating throughout life, producing new active cells all the time. "Your brain is a living and constantly developing dense forest with billions of neurons and synapses," says Alvaro Fernandez, founder and CEO of market research firm SharpBrains.

    The emerging science of neuroplasticity, which studies how our brains change and adapt, is revealing that, as with muscles, it's a case of "use it or lose it," he adds. "Once new neurons appear in your brain, where they stay and how long they survive depends on how you use them."

    Fernandez is co-author of a book called The SharpBrains Guide to Brain Fitness that boils down the current explosion of new research in this area to specific advice on what to do now to guard against Alzheimer's and other forms of cognitive impairment later on.

    By a lucky coincidence, there's plenty of overlap between what's good for your brain and what could turbo-charge your career. Consider these five tips:

1. Never stop learning. The latest research shows conclusively that, the better educated a person is, the less likely she is to suffer from age-related decline. "Highly educated people are likely to have mentally stimulating jobs," Fernandez notes, and that fosters the birth of new neurons. If you get into the habit of learning new skills throughout your career -- which also happens to make you more marketable and promotable -- your brain will thank you later.

2. Immerse yourself in another culture. In particular, learn another language. As U.S. business (especially marketing) becomes ever more bilingual, Spanish would be smart -- but, for the ultimate brain workout, pick Russian, Mandarin, or Arabic, whose different alphabets make them that much more challenging.

    If you can, volunteer for overseas gigs, too. Not only do these make your resume stand out from the crowd, but "exploring and adjusting to new locations forces you to pay more attention to your environment" than staying home, Fernandez notes. Navigating an unfamiliar culture, even for a short time, is like calisthenics for your brain.

3. Seek out tough "stretch" assignments. "The goal is to be exposed to novelty and increasing levels of challenge, so the task never becomes too easy or routine," Fernandez writes, adding that this means "expending effort and getting out of your comfort zone." Variety is as important as challenge, several new studies show: "Excessive specialization is not the best strategy for maintaining long-term brain health. A bond trader may thus want to try an artistic activity, to stimulate brain cells that he or she rarely uses otherwise."

4. Manage stress. "Excessive stress, no matter whether induced by external events or by your own thoughts, actually kills neurons and prevents the formation of new ones," Fernandez notes. Obviously, you don't want that. The SharpBrains Guide to Brain Fitness goes into detail on how physical exercise, meditation, and even having a good laugh help to protect your brain from the ravages of too much pressure, while heading off job burnout too. Taking a real vacation once in a while is also a proven stress fighter.

5. Have lots of friends. Not only is a vast and varied network of pals a huge advantage when you want to change jobs (or hire the right person), but it turns out that "social engagement contributes to brain health," Fernandez writes. New research shows that regularly interacting with a wide range of other people contributes to "both short-term performance boosts and the buildup of cognitive reserve."

    Is there an ideal number of friends? The human cerebral cortex, it seems, can efficiently process only a limited number of relationships, and that number (known to neuroscientists as Dunbar's number, after the researcher who found it) is 150. In an interesting aside, Fernandez notes that, although some people have thousands of Facebook friends, "the typical number is around 120, which corresponds roughly to Dunbar's number -- that is, the number of friends and acquaintances people generally have in real life."