You're tired. You could put your head down on a desk right now and fall asleep immediately. You went to bed late last night, had trouble falling asleep and woke up too early. And let's not kid ourselves: Tonight will be the same unless ... well, read on.

This is the classic not-so-shut-eye?? experience of many Americans who think they are sleep-deprived and possibly need pills or other treatment to fix their insomnia, teeth grinding, jet lag, restless or jerky legs, snoring, sleepwalking and so forth.

Reality is quite different.

For instance, insomnia is said to be the most common sleep disorder, but these dissatisfying sleep experiences only get in the way(妨碍) of daily activities for 10 percent of us, according to the National Institutes of Health. And in almost half of those cases, the real underlying problem is illness (often mental) or the effects of a substance, like coffee or medication.

Here are five recent findings that might help you rest easier:

1. We sleep better than we think we do

For most of us, sleep deprivation?? is a myth. We're not zombies. The non-profit National Sleep Foundation (which takes money from the sleep-aid industry, including drug companies that make sleeping pills) says the average U.S. resident gets 7 hours a night and that's not enough, but a University of Maryland study earlier this year shows we typically get 8 hours and are doing fine. In fact, Americans get just as much sleep nowadays as they did 40 years ago, the study found.

2. We need less sleep as we age

We'll die without sleep. The details are sketchy, but research suggests it's a time when we restore vital biological processes and also sort and cement memories. Last year, the World Health Organization determined that nightshift work, which can lead to sleep troubles, is a probable human carcinogen. On the upside??, the latest research suggests we need less of it as we get older.

3. You can sleep like a baby (or Thomas Edison)

Multiple, shorter sleep sessions nightly, rather than one long one, are an option. So-called polyphasic sleep is seen in babies, the elderly and other animals (and Thomas Edison reportedly slept this way). For the rest of us, it is more realistic and healthy to sleep at night as best we can and then take naps as needed. EEGs show that we are biphasic sleepers with two alertness dips — one at night time and one mid-day. So talk to HR about setting up a nap room, like they have for NASA's Phoenix mission?? team members.

4. Animals exhibit a range of sleep habits

The three-toed sloth sleeps 9.6 hours nightly. But newborn dolphins and killer whales can forgo sleeping for their entire first month. However, the latter extreme is not recommended for humans. We grow irritable and lose our ability to focus and make decisions after even one night of missed sleep, and that can lead to serious accidents driving and using other machinery.

5. Get used to being tired, hit the desk

The bottom line is that a good night's sleep is within the reach of most of us if we follow common-sense guidelines for sleep hygiene:

1)Go to bed at the same time nightly.
2)Set aside enough time to hit that golden 7 hours of sleep.
3)Refrain from caffeine, heavy or spicy foods, and alcohol and other optional medications that might keep you awake, four to six hours before bed-time.
4)Have a pre-sleep routine so you wind down before you hop in.
5)Block out distracting lights and noises.
6)Only engage in sleep and sex in bed (no TV-watching, reading or eating).
7)Exercise regularly but not right before bed.

But you already know all this and you don't do it. So your realistic plan might be to surrender to the mid-day desk nap.

现在你觉得很疲劳。且想着立刻就能把脑袋搁到桌子上，美美地睡一觉。昨晚，上床晚了吧，要么就是一宿没睡着加上起来太早了。得了，就别自欺欺人了：今夜又是不眠夜啊，除非……想知道？读下去吧。

这就是古今不二的辗转反侧了，以致许多美国人都认为他们的睡眠被剥夺了，甚至认为不吃点什么药或去医院上几个疗程，就没法治他们的失眠、磨牙、倒不过来的时差、烦躁不安或是小腿抽筋、打鼾、梦游等等如此这般的病。

事实与你想的完全不同

举例来说，失眠可以说是最常见的睡眠障碍，但据美国国家卫生研究所的说法，这些痛苦睡眠的体验，真正影响到了日常活动的，只占10％的人口而已。而且在这些案例有中将近一半，真正的潜在麻烦还是有病（当然多数是心理上的）或者是某些东西产生的影响，好比是咖啡或是你刚吃过的药。

这里有五个最近的调查结果，或可帮你更轻松地入眠：

１、我们的睡眠质量，比我们们想象中要好得多

对绝大多数人来说，睡眠的剥夺只能算是个神话。我们可不是僵尸（汗，就是不用睡觉的吧）。非盈利性的国家睡眠基金会（他们钱是从睡眠辅助器材的企业里拿，当然安眠药厂也是）的说法是这样的：全美居民的平均睡眠时间是7小时，这并不够，而马里兰大学在今年早些时候的研究表明：8小时睡眠才能让我们身心健康。但研究还表明，今天的美国人的睡眠时间和40年前一样多。

２、我们在长大，睡眠在减少

不睡觉我们会面对死亡。详情可能过于简略，不过研究表明：让我们恢复精力充沛的生物学过程，也是自己回忆的排列和巩固过程。就在去年，世界卫生组织认定，夜班工作导致的睡眠问题，是一个可能的致癌原因。而好处就是：最新的研究表明，随着年龄的增长，我们的睡眠需要反而会减少。

３、你可以睡得像婴儿或是托马斯爱迪生（一样听而不闻？）

一整晚频繁短暂而不是漫长的睡眠，可以只是一种选择。因此，所谓的多相睡眠被认为仅仅存在于婴儿、老年人和其他一些动物中（据报道托马斯爱迪生也是这样睡的）。至于我们这些人来说，更现实并且健康的做法就是酣然入梦、一夜好睡，还有只要一觉着累，最好就能打个盹什么的。脑电图显示，作为两阶段睡眠者的我们，每天确实有两段时间会警觉性下降－分别是晚上和中午。因此，每次谈到人力资源管理时，总会谈到午睡室的问题，就像美国宇航局为“凤凰”号火星探测任务的队员建造的那间一样。

４、动物所展现的睡眠习惯

三趾树懒每天要睡9.6小时。而新生海豚和杀人鲸可以在他们出生后的第一个月里完全不睡觉。只不过，第二个例子太过极端，所以不推荐人类采用。我们一夜不睡觉的话，就会心情烦燥、精力无法集中加上犹豫不决，如果是在驾驶或操纵仪器，那甚至会导致严重的事故。

５、假设你习惯了那种累的一头锤在桌子上就睡的日子

那么你的底线就是：只要有可能，那就好好睡上一觉，这是我们大部分人都力所能及的。

而且遵循以下睡眠卫生学的常识，我们能睡得更香甜：

(1)、每晚同一时间上床睡觉。
(2)、预留足够的时间以实现黄金7小时的睡眠。
(3)、在睡前4-6个小时中尽量避免摄入咖啡因、别吃太饱或太辣、请勿饮酒和服用会导致亢奋的药物。
(4)、若有剧烈活动，请在睡前先让自己平静下来。
(5)、尽量减少让人心烦意乱的灯光和噪音。
(6)、床上，只干睡觉和做爱这两件事（禁止电视、书还有食品）。
(7)、要经常锻炼，不过别在睡觉前。

即使你已经明白了这一切，可你不一定做得到。因此切实可行的计划，还是围绕着你中午的打盹来安排吧。