2017年06月六级第3套选词填空原文翻译及答案解析

Half of your brain stays alert and prepared for danger when you sleep in a new place, a study has revealed. This phenomenon is often __26__ to as the "first-night-effect". Researchers from Brown University found that a network in the left hemisphere of the brain "remained more active" than the network in the right side of the brain. Playing sounds into the right ears (stimulating the left hemisphere) of __27__ was more likely to wake them up than if the noises were played into their left ears.

一项研究揭示，当你在陌生地方睡觉时，一半的大脑保持警觉并准备应对危险。这种现象通常被称为“首夜效应”。布朗大学的研究人员发现，大脑左半球的一个网络比右半球的网络“保持更活跃”。向志愿者的右耳播放声音（刺激左半球）比向他们的左耳播放噪音更有可能唤醒他们。

It was __28__ observed that the left side of the brain was more active during deep sleep. When the researchers repeated the laboratory experiment on the second and third nights they found the left hemisphere could not be stimulated in the same way during deep sleep. The researchers explained that the study demonstrated when we are in a __29__ environment the brain partly remains alert so that humans can defend themselves against any __30__ danger.

特别观察到，在深度睡眠期间，大脑的左侧更为活跃。当研究人员在第二和第三个晚上重复实验室实验时，他们发现左半球在深度睡眠期间无法以相同方式被刺激。研究人员解释说，这项研究表明，当我们处于新环境时，大脑部分保持警觉，以便人类能够抵御任何潜在危险。

The researchers believe this is the first time that the "first-night-effect" of different brain states has been __31__ in humans. It isn't, however, the first time it has ever been seen. Some animals __32__ also display this phenomenon. For example, dolphins, as well as other __33__ animals, shut down one hemisphere of the brain when they go to sleep. A previous study noted that dolphins always __34__ control their breathing. Without keeping the brain active while sleeping, they would probably drown. But, as the human study suggests, another reason for dolphins keeping their eyes open during sleep is that they can look out for __35__ while asleep. It also keeps their physiological processes working.

研究人员认为，这是首次在人类中识别出不同脑状态的“首夜效应”。然而，这并不是首次观察到这种现象。一些动物物种也表现出这种现象。例如，海豚以及其他海洋动物在睡觉时会关闭大脑的一个半球。一项先前的研究指出，海豚总是谨慎控制它们的呼吸。如果在睡眠中不保持大脑活跃，它们很可能会淹死。但是，正如人类研究所表明的，海豚在睡眠中保持眼睛睁开的另一个原因是它们可以在睡觉时警惕捕食者。这也保持它们的生理过程正常运作。