It can be, but it can be good for you, too-a fact scientists tend to ignore and regular folks don't appreciate.

    If you aren't already paralyzed with stress from reading the financial news, here's a sure way to achieve that grim state: read a medical-journal article that examines what stress can do to your brain. Stress, you'll learn, is crippling your neurons so that, a few years or decades from now, Alzheimer's or Parkinson's disease will have an easy time destroying what's left. That's assuming you haven't already died by then of some other stress-related ailment such as heart disease. As we enter what is sure to be a long period of uncertainty-a gantlet of lost jobs, dwindling assets, home foreclosures and two continuing wars-the downside of stress is certainly worth exploring. But what about the upside? It's not something we hear much about.

    In the past several years, a lot of us have convinced ourselves that stress is unequivocally negative for everyone, all the time. We've blamed stress for a wide variety of problems, from slight memory lapses to full-on dementia-and that's just in the brain. We've even come up with a derisive nickname for people who voluntarily plunge into stressful situations: they're "adrenaline junkies."

    Sure, stress can be bad for you, especially if you react to it with anger or depression or by downing five glasses of Scotch. But what's often overlooked is a common-sense counterpoint: in some circumstances, it can be good for you, too. It's right there in basic-psychology textbooks. As Spencer Rathus puts it in "Psychology: Concepts and Connections," "some stress is healthy and necessary to keep us alert and occupied." Yet that's not the theme that's been coming out of science for the past few years. "The public has gotten such a uniform message that stress is always harmful," says Janet DiPietro, a developmental psychologist at Johns Hopkins University. "And that's too bad, because most people do their best under mild to moderate stress."

    The stress response-the body's hormonal reaction to danger, uncertainty or change-evolved to help us survive, and if we learn how to keep it from overrunning our lives, it still can. In the short term, it can energize us, "revving up our systems to handle what we have to handle," says Judith Orloff, a psychiatrist at UCLA. In the long term, stress can motivate us to do better at jobs we care about. A little of it can prepare us for a lot later on, making us more resilient. Even when it's extreme, stress may have some positive effects-which is why, in addition to posttraumatic stress disorder, some psychologists are starting to define a phenomenon called posttraumatic growth. "There's really a biochemical and scientific bias that stress is bad, but anecdotally and clinically, it's quite evident that it can work for some people," says Orloff. "We need a new wave of research with a more balanced approach to how stress can serve us." Otherwise, we're all going to spend far more time than we should stressing ourselves out about the fact that we're stressed out.

    When I started asking researchers about "good stress," many of them said it essentially didn't exist. "We never tell people stress is good for them," one said. Another allowed that it might be, but only in small ways, in the short term, in rats. What about people who thrive on stress, I asked-people who become policemen or ER docs or air-traffic controllers because they like seeking out chaos and putting things back in order? Aren't they using stress to their advantage? No, the researchers said, those people are unhealthy. "This business of people saying they 'thrive on stress'? It's nuts," Bruce Rabin, a distinguished psychoneuroimmunologist, pathologist and psychiatrist at the University of Pittsburgh School of Medicine, told me. Some adults who seek out stress and believe they flourish under it may have been abused as children or permanently affected in the womb after exposure to high levels of adrenaline and cortisol, he said. Even if they weren't, he added, they're "trying to satisfy" some psychological need. Was he calling this a pathological state, I asked-saying that people who feel they perform best under pressure actually have a disease? He thought for a minute, and then: "You can absolutely say that. Yes, you can say that."

    如果你不想因为阅读经济新闻而崩溃，这有条路可以走：去读一篇医学期刊，看看对于你什么压力更适合。你将明白，压力这东西会使你的神经崩溃，并且使得阿尔茨海默病或者帕金森病更容易在几年后侵蚀你。由此可以推测出，你不会死于其他那些很短时间致命的疾病。当我们确定进入不确定的长时期（一连串的失业、资产损失、家庭赎回和长达两年的夫妻之战）时，这个事情值得好好研究下。但是什么是往上走的？没有人告诉我们。

    在过去的几年里，我们中的大多数人相信我们自己，压力总是不公平倾斜到每个人身上的。在很多问题上，无论是小的记忆丢失还是老年痴呆症，我们都把黑锅推给压力来背--而这仅仅是在大脑中。我们甚至嘲笑那些人，他们自愿投身到紧张这样一种状态：他们称为"肾上腺素迷们".

    当然，压力对你来讲不全是不好的，特别是如果你从生气或失望或喝下5背苏格兰威士忌中反应过来。但是，一个普通的感觉点常常忽视：在某些情况中，压力同样对你来说也可能是好事。在基础心理学课本中，这么说是正确的。就像Spencer Rathus说的那样："心理学：概念和连线","有些压力是健康并且必须的，以此来使我们警惕和有足够的注意力。"但是这个理论在过去的几年中并没有科学依据。"大众总是收到统一的信息，压力总是不好的。"Janet DiPietro说，他是Johns Hopkins 大学的发展心理学家，"而这非常不好，因为更多的大众进他们全力去维持比较温和的压力。"

    压力的反馈--身体荷尔蒙分泌会很危险、不定量或者改变--这些都会帮助我们存活下来，并且如果我们明白怎样从我们的生活中远离过度劳累，他仍然可以起作用。短期内，压力可以使我们更有活力，"我们身体系统要来处理我们不得不处理的东西。"Judith Orloff说，他是加州大学洛杉矶分校的精神科医生。长期内，压力可以促使我们在工作上作的更好。一点点的压力可以促使我们制造出来很多，是我们更富有弹性。既是当压力到了极限，他也可能有默写积极效果--这也是为什么，一些精神科医生开始定义创伤后应激障碍为：创伤后成长。"真正的生物化学和科学偏见说压力总是不好的，但是临床上说，确实有证据说明压力对某些人来说有意义。"Orloff说，"我们需要一个新的研究姿态来找出一个更好的办法使压力更好的服务于我们。"否则，我们会在让我们自己跳出压力这方面浪费很多时间，而事实是我们强调了。

    当我开始告诉研究者们"压力的益处"时，他们中的大多数说这个基本上不存在。"我们从不告诉大众压力对他们有益。"其中一个说。另外一个允许它存在，但仅仅在某些小方面存在，在很短的时间里存在。那些饱受压力摧残的人怎么样呢？我问--那些是警察、急诊室文件管理者、空中协管员，因为他们看起来沉溺于混留言之中而使各类事物有序。他们不吧他们经历过的压力看做是一种优势么？不，研究院回答，这类人心里不健康。"这类人说他们'沉溺于压力'中？这是事实。"Bruce Rabin告诉我。他是Pittsburgh School of Medicine学校的病理神经学家、病理学家及精神病学家。他说，那些沉溺于压力并且相信这样的状态会使他们成瘾的成年人在长期受到高水平的肾上腺素和皮质醇影响下，像孩子一样或者受到长期影响。甚至他们以前不这样，他补充道，他们"试着去满足"一些生理需求。他是否到达了一个病理状态？我问道--传说那些感觉到他们做的很好的是否有问题呢？他想了一下说："你几乎是在说：是的，你可以这么说。"