睡不着?也许是因为你太累了

We're used to seeing toddlers who can't switch off at bedtime. But some experts think that our 'always on' lifestyles mean that many adults have the same problem
两三岁的小孩在临睡前总是不停地讲话，我们对此已习以为常。但一些专家认为，我们'总是清醒'的生活方式意味着很多成年人也有着相同的问题。

Nerina Ramlakhan remembers when her daughter was a toddler, and how if she got too tired she would be unable to switch off. "There was a healthy level of tiredness," she says. "But if she went beyond that, she would be running on a kind of false energy. And then she wouldn't be able to switch off when she went to bed."
奈丽娜·拉姆拉罕犹记得女儿蹒跚学步那会儿很累但却无法停下来休息的场景。"疲惫也是有健康程度的，"她说道。"如果越过这一程度，她就会消耗某种虚假能量。所以当她上床睡觉时，根本无法入睡。"

Overtiredness is recognised the world over in young children - but it is seemingly more and more common in adults. Dr Ramlakhan should know: she is a sleep psychologist and is increasingly seeing people who remind her of her little girl when she was younger.
全世界都承认幼儿过劳这一情况--但似乎过度劳累在成年人群中也越来越普遍。拉姆拉罕博士应该知道：她是一位睡眠心理学家，越来越多的人让她想起自己年轻时女儿的样子。

Overtiredness, sleep experts agree, is down to our always-on existence. In the past, says Ramlakhan, the author of The Little Book of Sleep, our days had naturally built-in downtime that gave us short snatches of rest. Today, that has disappeared for many of us.
专家认为，过度劳累是由于我们总是保持清醒所致。《睡觉这件小事》（The Little Book of Sleep）一书的作者拉姆拉罕说道，过去，我们日出而作日落而息，但现在，很多人却做不到这一点。

"We have become restless as a society - and that places more demands on us when we get into bed at night," she says. "We have lost the rituals and practices that gave us little respites during the day. In the past, you would go to the supermarket and, while you were waiting in the queue, you'd daydream, be a bit bored, look around. Now, any window like that will be filled by looking at your phone, answering some emails, sorting out your Amazon account."
"作为社会的一份子，我们变得难以入睡--夜晚当我们上床睡觉时，社会对我们提出了更多要求，"她说道。"我们遗失了白天短暂休息的仪式和习惯。过去，在超市排队结账的时候，你可能会做会儿白日梦，可能会有点无聊的环顾四周。但现在，任何一个结算窗口的队列里都是玩着手机、回复邮件、清理亚马逊账号的客人。"

You may think you are putting the time to good use - but that's not how your brain interprets it. There's a complex neurophysiology that requires breaks in tasks and concentration; if it's constantly bombarded, the brain becomes overloaded. The result, says Ramlakhan, is that it goes into what we might call survival mode: it assumes that something bad is about to happen, it ups the adrenaline and it puts out an urgent call for sugary snacks to provide quick-release energy.
也许你觉得自己在充分利用时间--但你的大脑却没有如此解读。复杂的神经心理学需要我们在做任务、集中注意力的空档找机会休息；持续被各种信息轰炸会导致大脑过载。拉姆拉罕说，结果导致生存模式开启：大脑以为一些不好的事情即将发生，从而刺激肾上腺素，并紧急利用含糖零食快速释放能量。