雅思阅读材料：缺觉对大脑的损害等于头部受重击

　　Ever feel like you’ve been hit on the head after a bad night’s sleep? According to scientists, the thought isn’t as far-fetched as it seems.

　　如果晚上没睡好，第二天会不会有种撞过头的感觉?据科学家研究，这种想法和实际情况相差不远。

　　A study found going without sleep for just one night causes changes in the brain similar to those that occur after a blow to the head.

　　一项研究发现，即使只通宵一晚，对大脑造成的损伤足以抵得上对头部的一次重击。

　　The researchers said the healthy young men examined in the study showed a spike in the same chemicals which indicate brain damage.

　　研究人员说，研究中接受检查的健康年轻人显示出一种会导致脑损伤的化学物质剧增。

　　Professor Christian Benedict, of Uppsala University, Sweden, explained that the chemcials NSE and S-100B are biomarkers for brain damage, such as concussion.

　　瑞典乌普萨拉大学克里斯蒂安·本尼迪克特教授解释说，化学物质NSE和S-100B是脑损伤(比如脑震荡)的生物标记。

　　He said: ‘What we found was their levels in the blood rose in the group that went without sleep for a night. This was not to the extent that would happen after a head injury, for instance, but it was still significant.

　　他说：“我们发现的是在一晚没睡的人群中，NSE和S-100B在血液中含量上升了。这虽然还不到一次头部外伤的程度，不过也很值得注意了。”

　　‘During sleep, the brain cleans itself of toxic substances and NSE and S-100B increase in response to these substances.’

　　“大脑通过睡眠来清除自身的有毒物质，NSE和S-100B则对这些物质做出反应”。

　　He said the findings back up previous research showing how the brain uses sleep to cleanse itself.

　　他说这项研究支持了之前的研究结果，即大脑怎样用睡眠来自我净化。