You have an important presentation tomorrow but your heart is racing and your mind is serving up a steady stream of what-ifs: What if I'm not fully prepared? What if it goes badly? You're running out of time. The last thing you need is all this anxiety.
明天你有一场重要的演讲，但你心里像揣着只小兔子，脑子里装满各种疑问：如果我还没准备好怎么办？如果演讲讲砸了怎么办？你没多少时间了。眼下你最不需要的就是心中这焦虑了。
Actually, a little anxiety may be just what you need to focus your efforts and perform at your peak, psychologists say.
然而实际上，据心理学家们称，适度的焦虑可能恰恰是你要集中精力、达到巅峰状态时所需要的东西。
Somewhere between checked out and freaked out lies an anxiety sweet spot, some researchers say, in which a person is motivated to succeed yet not so anxious that performance takes a dive. This moderate amount of anxiety keeps people on their toes, enables them to juggle multiple tasks and puts them on high alert for potential problems.
一些研究者表示，在安然过关与紧张到崩溃之间有一个微妙的焦虑平衡点，只要焦虑度没有超出这个平衡点，人们就能在焦虑的刺激下获得成功，而不是因压力过大而表现失常。这个适度的焦虑能够让人们保持警醒，使得他们得以同时应付多项任务，并对可能出现的问题随时保持高度的警惕。
"Coaches and sports psychologists have always known that you don't want your athlete to be relaxed right before an event. You need some "juice" to go fast," says Stephen Josephson, a psychologist in New York City who has treated athletes, actors and musicians.
纽约心理医师斯蒂芬•约瑟夫森(Stephen Josephson)表示，“体育教练和运动心理学家很清楚，在比赛前夕不能让运动员太过放松了。你需要一些刺激来让自己出色发挥。”约瑟夫森曾为一些运动员、演员和音乐家提供过心理咨询服务。
It can be tricky to achieve. Some overly optimistic people and those with attention-deficit hyperactive disorder may lack enough anxiety to take action. Others - mostly procrastinating perfectionists - must create anxiety-producing situations in order to get anything done.
有时候成功完成一项任务也许没那么容易。一些过于乐观的人，以及那些患有注意力缺陷多动障碍(attention-deficit hyperactive disorder)的人可能会缺乏足够的焦虑来刺激他们行动起来。还有些人──大多数是办事拖沓的完美主义者──则必须制造出一个能产生紧张感的环境才能顺利完成工作。
Regulating anxiety is also difficult because humans' ancient threat-detection system hasn't kept pace with modern man's ability to fret about the future, ruminate about the past and imagine all kinds of terrible scenarios, says Dennis Tirch, associate director of the American Institute for Cognitive Therapy in New York. So the body's primitive fight-or-flight response kicks in even when the threat at hand is a daunting social engagement or a 20-page report.
纽约美国认知疗法协会(American Institute for Cognitive Therapy)副会长丹尼斯•蒂尔奇(Dennis Tirch)表示，管理焦虑也是一件难事，因为人类的威胁察觉系统自远古进化发展而来，与现代人担忧未来、反思过去、以及想象各种可怕场景的能力并不同步。因此，一旦威胁来临，哪怕所面临的威胁只是一项令人头疼的社会责任，或是一份20页的报告，但人们“要么战斗要么逃离”的原始反应机制便会立即发生作用。
Of course, too much anxiety can be painful and destructive. Anxiety disorders affect about 40 million American adults - 18% of the population - in a given year, according to the National Institute of Mental Health. Only about one-third of them seek treatment. The disorders run the gamut from panic attacks and specific phobias to obsessive-compulsive disorder, post-traumatic stress disorder and generalized anxiety disorder, a random kind of worry described as free-floating and relentless. Sufferers also have a high incidence of depression and physical ailments, including migraines, high blood pressure, heart disease, digestive disorders and chronic pain, according to NIMH.
诚然，焦虑过度或许会让人感到痛苦，而且也极具破坏性。根据美国国家心理健康研究所(National Institute of Mental Health)的数据，美国某一年当中受焦虑症困扰的美国成年人数约为4,000万，相当于美国人口的18%。其中只有三分之一左右的患者寻求治疗。焦虑症具体包括很多种类，比如突发性恐慌、针对特定事物的恐惧症，此外还有强迫症、创伤后紧张症、以及一种随时可能陷入忧虑状态的广泛性焦虑症。据美国国家心理健康研究所称，焦虑症患者同时伴随出现抑郁症以及偏头痛、高血压、心脏病、消化系统紊乱以及慢性疼痛等身体疾病的机率也很高。
The terms anxiety and stress are often used interchangeably, although stress includes anger and frustration, while anxiety is typically worry and unease.
焦虑(anxiety)和紧张(stress)这两个词经常可以相互替代使用，不过紧张一般是伴随着怒气和挫败感，而焦虑通常是指担忧和不安。
The notion that moderate anxiety can be beneficial goes back at least to 1908, when Harvard psychologists Robert Yerkes and John Dodson posited that arousal (as they called it) enhances performance - but only to a point. When anxiety gets too high, performance suffers instead.
适当的焦虑可能会带来好处这个观点往前至少可以追溯到1908年，哈佛大学心理学家罗伯特•耶基斯(Robert Yerkes)和约翰•多德森(John Dodson)在那一年提出这样一个假设：保持一定的“警醒度”（他们用了这个词）可以提升表现，不过只在一定程度上。当焦虑过甚，表现反而会受到负面影响。
The Yerkes-Dodson curve - an upside-down U shape - is still taught in psychology courses, and modern neuroscience has helped confirm it. Studies have shown, for example, that the brain learns best when stress hormones are mildly elevated.
耶基斯-多德森曲线（一条先升后降的倒U形曲线）如今仍是心理学课程上的一项内容，且得到了现代神经系统学的证实。比如说，有研究表明，当应激激素水平略有提高时，大脑的学习能力最强。
High anxiety can make even simple tasks more difficult, says psychologist Jason Moser at Michigan State University.
密歇根州立大学(Michigan State University)的心理学家杰森•莫泽(Jason Moser)称，较高的焦虑水平甚至会让一项简单的任务变得难以完成。
In a study published earlier this month in the International Journal of Psychophysiology, he and his colleagues monitored the brain activity of 79 female and 70 male students while they performed a letter-identifying exercise. The students performed equally well at first, but the women who identified themselves as highly anxious had to work harder at it. Those subjects showed far more activity in a part of the brain - the anterior cingulate cortex - thought to be a center of anxiety. And once the worrying women started making errors, they made them at a higher rate than the other subjects, suggesting that the extra effort the anxiety caused was taking a toll, Dr. Moser says.
莫泽和他的同事于今年6月份在《国际心理学期刊》(International Journal of Psychophysiology)上合作发表了一项研究结果，该研究对79名女学生和70名男学生在完成一个辨别字母的练习过程中的大脑活动进行了监测。起初学生们的表现同样良好，不过那些认为自己高度焦虑的女生完成练习时需要付出更大的努力。这部分学生大脑中的前扣带皮层──这部分脑组织被认为是控制焦虑的中枢──表现得比其他学生活跃很多。莫泽称，而一旦这些焦虑的女生开始犯错误，这些最初的错误会使得她们的错误比率超出其他学生，这意味着焦虑引发的额外努力正让她们付出代价。
How do you find the sweet spot between anxiety that energizes and anxiety that paralyzes?
怎样才能在激励表现和破坏表现之间，找到这个适度焦虑的平衡点呢？
Most therapists see more patients suffering from too much anxiety rather than too little, although withdrawal and lack of ambition can be a hallmark of depression. Dr. Josephson says that overly optimistic people with ADHD often have an insufficient sense of urgency to get things done. One form of treatment is what he calls "motivational interviewing: stressing the negative future consequences of not finishing and explaining that once the task is through, they'll feel a sense of calm and relief," he says.
大多数心理医师接待的焦虑症患者中，受焦虑过度困扰的人要多于焦虑刺激不足的人，不过缺乏行动动机有可能是抑郁症的表现。曼哈顿的心理医师约瑟夫森称，患有注意力缺陷多动障碍的过份乐观患者通常缺乏足够的紧迫感来完成一件事。他说，其中一个治疗方式是被他称为“动机式晤谈法“的治疗方法，即强调如果任务不完成未来可能发生的各种负面后果，并向患者解释，一旦任务完成，他们将感到平静和欣慰。
Another group of people can't get anything done without some level of anxiety. "There are people who subconsciously set life up to give them a thrill, by always being almost late, nearly missing a deadline, spending more than they should," says Marianne Legato, a professor of clinical medicine at Columbia University in New York. "I call them fretters."
另外一类患者在没有一定水平的焦虑感刺激下，会一事无成。纽约哥伦比亚大学(Columbia University)临床医学教授玛丽安•雷加图(Marianne Legato)说，“有一类人总是下意识地让自己的生活陷入一种惊险状态，他们经常会差一点就迟到、或是赶不上最后期限，他们总是要花费比正常状态更多的时间。我将这类人称为烦躁者。”