Land Sickness登陆病
Seasickness happens when a person’s body struggles to grow accustomed to a boat’s motion patterns， causing them to feel unsteady and often nauseated. But land sickness happens in reverse： A person’s body adapts to the motion of the waves， then struggles to return to homeostasis after reaching solid ground. Someone might sway or rock after leaving a boat; they may even begin to feel ill.
晕船是指人体难以适应船的摆动，导致身体重心不稳，还常伴随着恶心。但登陆病则相反：人体适应了海浪带来的晃动，到达陆地后体内却难以恢复平衡。有些人下船后可能会前后左右摇晃，他们甚至可能会开始感到身体不适。
What is land sickness？
什么是登陆病？
One of the earliest known references to land sickness came from Erasmus Darwin in 1796， who wrote： “Those， who have been upon the water in a boat or ship so long， that they have acquired the necessary habits of motion upon that unstable element， at their return on land frequently think in their daydreams， or between sleeping and waking， that they observe the room， they sit in， or some of its furniture， to librate like the motion of the vessel. This I have experienced myself， and have been told， that after long voyages， it is some time before these ideas entirely vanish.”
关于登陆病的最早记载来自伊拉斯谟斯·达尔文，他于1796年提道：“那些在船上待了很长时间的人，他们已经习惯了这种不规律的晃动。当他们回到陆地上后，时常在幻想或半梦半醒时感觉到他们所在的房间或周围的一些家具会像船一样晃动。我亲身经历过，也有人告诉过我，在远航之后，这些感觉要过一段时间才会完全消失。”
As Darwin’s description suggests， land sickness typically happens after someone has been out at sea for an extended trip， although the duration of their time on the water doesn’t necessarily correlate to the severity of their symptoms. Boats aren’t the only things to blame; airplanes and trains can also cause people to feel this sense of imbalance and unease.
据达尔文的描述可知，登陆病通常发生在人们长时间出海后，尽管他们在海上待的时间长短并不一定与症状的严重程度相关。轮船并不是唯一的原因，飞机和火车也会让人产生这种不平衡和不适的感觉。
Some estimates suggest between 43 and 73 percent of people experience land sickness. The disorder can happen to anyone， but women from the age of 30 to 60 are more susceptible to it， as are those who experience migraines.
一些估计显示有43%至73%的人患有登陆病。任何人都可能表现出这种病症，但30至60岁的女性和偏头痛患者更容易有这种病。
What causes land sickness？
什么原因导致登陆病？
The exact cause of land sickness is still unknown. One of the leading theories is that consistent motion disrupts a person’s vestibular system. The vestibular system， which is located in the inner ear， is what helps people stay balanced and remain aware of their body’s position in space.
登陆病的确切病因尚未可知。目前有一种主流言论：持续性的晃动会扰乱人的前庭系统。前庭系统位于内耳，帮助人们的身体保持平衡并保持对空间的感知。
After prolonged exposure to a wave-like motion， a person’s body is typically able to adapt to the new environment. They’ll get used to the continual rocking movement. But once that motion stops， the person’s brain may continue reading the environment as if the waves are still rolling. This conflicting sensory information confuses the body and disrupts the vestibular system， making a person prone to feeling nauseated， unsteady， and generally unwell.
长时间待在海浪翻涌的环境中后，人体通常能够适应这种新环境，他们会习惯这种持续性的晃动。但这种晃动一旦停止，人的大脑可能会继续感知环境，就好像海浪仍在翻涌一样。这种相互矛盾的感觉信号会使身体接收到错误信息，扰乱前庭系统，使人容易感到恶心、不稳和身体不适。
Land sickness typically disappears after a person has spent a few days on land， but there have been documented cases of the condition lasting for months or even years.
通常人们在陆地上待上几天之后，登陆病的症状就会消失，但也有记录显示，这种症状会持续数月甚至数年。
Word Bank
sway /sweɪ/ v. （使）摇摆，摇动
correlate /'kɒrəleɪt/ v. 相互关联影响
susceptible /sə'septəbl/ adj. 易受影响（或伤害等）
prone to易于遭受……的；倾向