Eyes open, brain shut.
Eyes open, brain shut.
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眼睛睁着，大脑闭着。
DOI：
10.1038/scientificamerican0507-84
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发表时间：
2007
影响因子：
3
通讯作者：
Steven Laureys
中科院分区：
文献类型：
--
作者：
Steven Laureys
医生可以挽救许多遭受脑部创伤（通常是在交通事故之后）或缺氧（例如，在心脏骤停或溺水之后）的病人的生命，但如果损伤严重，受害者就会陷入昏迷。在这种情况下，个体不会睁开眼睛；充其量，他们会表现出肢体的一些反射运动。昏迷很少持续超过两到五周。那些恢复意识的人通常会在几天内恢复意识。有些人会死亡，还有一些人会从昏迷中醒来，但仍然没有意识，进入所谓的植物人状态。即使对专家来说，植物人状态也是一种非常令人不安的状态。它说明了意识的两个主要组成部分是如何完全分离的：清醒保持完整，但意识——包括所有的思想和感觉——被废除了。我所说的清醒是指植物人状态下的病人有睡眠/觉醒周期。在他们似乎醒着的时候，他们的眼睛睁着，有时会徘徊。在其他时候，他们闭着眼睛，看起来像是睡着了，尽管当被触摸或与他们说话时，他们可能会睁开眼睛，动一动。这些病人通常可以在没有技术帮助的情况下呼吸，并能做出各种自发的动作——比如磨牙、吞咽、哭泣、微笑、抓住别人的手、咕哝或呻吟——但这些动作总是反射性的，而不是有目的行为的结果。通常情况下，患者不会长时间盯着任何东西，但在极少数情况下，他们可能会短暂地跟随一个移动的物体，或者迅速转向一个响亮的声音。
Doctors can save the lives of many patients who suffer trauma to the brain (often after a road accident) or a lack of oxygen (for example, after a cardiac arrest or drowning), but if the damage is severe, the victim will slip into a coma. Individuals in this condition do not open their eyes; at best, they will show some reflex movements of the limbs. Coma rarely lasts longer than two to five weeks. Those who regain consciousness typically do so within days. Others will die, and still others will awaken from their coma but remain unconscious, entering what is called the vegetative state. Even for experts, the vegetative state is a very disturbing condition. It illustrates how the two main components of consciousness can become completely dissociated: wakefulness remains intact, but awareness—encompassing all thoughts and feelings—is abolished. By wakefulness, I mean that patients in a vegetative state have sleep/wake cycles. At the times when they seem to be awake, their eyes open and sometimes wander. At other times they keep their eyes shut and appear to be asleep, although they may open them and stir when touched or spoken to. These patients usually can breathe without technical assistance and can make a variety of spontaneous movements—such as grinding teeth, swallowing, crying, smiling, grasping another’s hand, grunting or groaning—but these motions are always reflexive and not the result of purposeful behavior. Typically patients will not fix their eyes on anything for a sustained period, but in rare instances they may briefly follow a moving object or turn fleetingly toward a loud sound.