If you get seasick easily, you may prepare for boat rides with pressure-point bracelets, ginger, or a prescription skin patch. Now there's one more remedy: timing your breathing to counteract the nauseating motion. The technique presumably works because it helps control gravity sensors in the abdomen--a lesser-known input to our fine-tuned balance system.

　　如果你很容易晕船，可以在登船时戴上能够施加压力的手镯，或是服用生姜，再或是贴上一副处方药膏。而如今又出现了新的疗法：与恶心反应保持协调的调整呼吸。这种方法的原理可能是由于它调控了腹部的压力感受器——一类我们鲜为人知的正常平衡系统中的感觉末梢。

　　The brain is traditionally thought to sense body position in three ways. The inner ears sense motions of the head; the eyes see where the head is; and tiny sensory organs in muscles and tendons sense where the rest of the body is. More recently, researchers have realized that sensors in many other parts of the body also play a role: in the abdomen, the lower organs, and even blood vessels. As long as all of these sensors send matching signals to the brain, we feel oriented. But if one or two don't match up, the brain gets confused and we become nauseated.

　　传统观念认为，大脑能够感受身体来自三个方向的运动。内耳感受头部的运动方向，眼睛分辨头部的活动走向，而肌肉和肌腱中的微小感受器能够感觉到身体其他部位的移动。最近又发现了新的研究成果：研究人员认识到，在身体其他部位也具有起这种作用的感受器，如腹部下面的脏器，还有血管。只要这些感受器将相关的信息传导至大脑，我们就能感受到它的方位。但如果其中有一两个不能正确匹配，大脑就会“疑惑”，我们可能就会感到恶心。

　　Scientists knew the most sickening motions closely match the rate of natural breathing; they also knew that people naturally tend to breathe in time with a motion. In fact, Navy seamen in World War II discovered that they could use certain breathing tricks to combat motion sickness. But no one had ever tested whether breathing out of time with a motion could prevent nausea.

　　科学家发现最让人感到恶心的反应和自然呼吸节律息息相关，人们会自然的通过动作及时调整呼吸。事实上，早在二战时期海军船员们就发现可以通过一定的呼吸技巧抵御这类晕动病。但没有人知道如果是不合时宜的呼吸配合身体动作是否能够预防恶心的发生。

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　　Researchers from Imperial College London enlisted 26 volunteers to sit in a tilting, rocking flight simulator and coordinate their breathing in various ways with the motion. The tests lasted up to 30 minutes, or until subjects felt moderately sick. The natural tendency was for volunteers to inhale on every backward tilt, in rhythm with the rocking. But if the subjects exhaled on every backward tilt, they didn't get sick as quickly. They felt even better if they breathed slightly faster or slower than the cyclic heaving of the chair; using that technique, the time until onset of nausea was 50% longer than during normal breathing.

　　伦敦皇家学院的研究人员将26名志愿者安置在倾斜着并呈摆动式升降的装置上，让他们以某种呼吸方式配合身体的动作。实验持续30分钟直到受试者感到一定的不适。志愿者往往都会根据摆动的节奏在每次向后倾斜时吸气。但若受试对象在每次后倾时呼气，就立刻不会感觉到难受了。如果稍微加快或减慢呼吸的节律，而不是反复的提升座椅的话会感到更加舒服。利用这项技术可以使在正常呼吸状态下直至发生恶心的时间延长50%。

　　So why do these tactics work? Abdominal sensors are known to send motion signals to the brain more slowly than those in the inner ear because they're farther away from the brain and because abdominal organs have more mass, which means they resist movement a tiny bit longer. The time lag between the two types of sensors creates a mismatch that builds up in the brain and makes us gradually sicker, the researchers say. But if the diaphragm opposes gravity-induced stomach motions with controlled breaths, there is less sensory conflict and less nausea. "This technique is very good for mild everyday challenges," says medical research scientist Michael Gresty, a member of the study team. "It's completely safe, and it's not a drug." The results appear in the December issue of Autonomic Neuroscience.

　　那么这些方法为什么能够奏效呢?人们已知腹部传感器给大脑发送信号要比内耳慢，因为它离大脑更远且腹部脏器含有较多的杂质，这就意味着它们对抗晃动的时间会更长一些。这两种感受器之间在时间上的间隔导致了错误的匹配，后者一旦在大脑中建立时就会使人渐渐感到不适，研究人员这样解释道。如果膈膜阻碍通过呼吸来控制的由重力引起的胃部运动，则会减少感受器之间的“争斗”，从而减轻恶心的感觉。身为研究小组成员之一的医学研究中心科学家迈克尔·格雷斯蒂说：“这种技术对每天进行野外作业的人来说很合适。它不像药物，安全性是完全有保障的。”这项研究成果在十二月的《自主神经科学》期刊上进行了发表。

　　"It's a carefully designed study that shows there's some modest effect of controlled respiration on motion sickness," says neuroscientist Carey Balaban of the otolaryngology department at the University of Pittsburgh in Pennsylvania. But, he says, more controlled experiments are needed to confirm the proposed mechanism.

　　宾夕法尼亚州匹兹堡大学耳鼻喉学院的神经科学家卡勒·巴拉班说：“这项周密的研究表明，通过控制呼吸来对付因为晃动造成的不适感只能起到些许作用。我们还需要更多的控制性实验来论证这个假设的作用机理。”