Jessa Gamble: 我们的自然睡眠周期

============================
http://dotsub.com/view/2a6f82ce-af6f-4dbb-9812-eb18f4059d50
Jessa Gamble: 我们的自然睡眠周期
让我们从日夜开始。 生命的进化在 光明与黑暗中进行， 光明，然后是黑暗。 因此植物和动物 都进化出自己的内部时钟， 这使得他们能适应光线的改变。 这是化学时钟， 每个已知的多细胞生物体内都有这种时钟， 部分单细胞生物也有这种时钟。
举个例子。 如果你从海滩上抓一只鲎， 把它空运到大陆的另一端， 接着把它放入一个倾斜的笼子里， 在它数千里外家乡的海岸 涨潮的时候， 它会爬到笼子的高处。 而退潮时它又会 退回笼子底部。 这种行为它会重复数个星期， 直到它渐渐失去这种判断能力。 这非常不可思议， 但这不是什么灵异或是超自然现象； 原因很简单，这些鲎拥有 能与周围环境相协调的内部周期。
我们也有这种能力。 就人类而言，我们称之为生物钟。 当你拿走某个人的手表，把他关进一个深入地下的地下堡垒 关上几个月，你就能更清楚地观察到 生物钟的作用。 实际上有志愿者做过这个实验， 他们从洞里出来时 对他们在洞里的时间有点混乱。 不管这些志愿者显得多不合逻辑， 有一件事可以确认。 他们每天都比之前晚起一点--大约15分钟左右-- 在这几星期内他们的生物钟就 像这样不断向后推延。 而且，就这样，我们知道他们是用自己的生物钟做到这点的， 而不是用某种方式感知外面的日光。
那么好的，我们有生物钟， 并且它对我们的生活极其重要。 它也是文化的巨大推动力， 我认为这是在我们的行为中最被低估的一种力量。 我们人类是从赤道附近进化而来的一个物种， 因此我们能非常好的 适应12小时的白昼和 12小时的黑夜。 不过当然，我们现在已经遍布全球的每个角落， 在我居住的加拿大北极地区， 夏天是极昼， 而冬天则是极夜。 因此传统上北部原住民文化 是高度季节性的。 在冬天，睡眠时间很长。 人们在室内享受家庭生活。 而在夏天则是疯狂的狩猎 及很长时间的劳作， 非常活跃。
那么，我们的自然节奏应该是什么样的呢？ 我们的理想中的睡眠模式 应是什么样的呢？ 嗯，事实表明， 当生活在完全没有 任何人工光源的环境中时， 人们会每晚睡两次。 人们在晚上8点左右睡觉。 直到午夜， 接着再次入睡， 大约从凌晨2点直到日出。 在这两次睡眠之间，有几个小时 在床上安静的沉思。 在这段时间内， 催乳素产生 这样的情况在现代社会不会出现。 这些研究中的人们 在白天觉得很清醒， 他们意识到 正在经历生命中的 第一次真正的失眠。
那么，转到现代社会。 我们的文化中充满时差， 全球旅行， 24小时营业， 倒班工作。 你知道，我们现代人的 这种生活方式 有它的优点， 但我想我们应该明白所付出的代价。
谢谢。
（掌声）


-----------------------------
Jessa Gamble: Our natural sleep cycle
Let's start with day and night. Life evolved under conditions of light and darkness, light and then darkness. And so plants and animals developed their own internal clocks so that they would be ready for these changes in light. These are chemical clocks, and they're found in every known being that has two or more cells and in some that only have one cell.

I'll give you an example. If you take a horseshoe crab off the beach, and you fly it all the way across the continent, and you drop it into a sloped cage, it will scramble up the floor of the cage as the tide is rising on its home shores, and it'll skitter down again right as the water is receding thousands of miles away. It'll do this for weeks, until it kind of gradually loses the plot. And it's incredible to watch, but there's nothing psychic or paranormal going on; it's simply that these crabs have internal cycles that correspond, usually, with what's going on around it.

So, we have this ability as well. And in humans, we call it the body clock. You can see this most clearly when you take away someone's watch and you shut them into a bunker, deep underground, for a couple of months. People actually volunteer for this, and they usually come out kind of raving about their productive time in the hole. So, no matter how atypical these subjects would have to be, they all show the same thing. They get up just a little bit later every day -- say 15 minutes or so -- and they kind of drift all the way around the clock like this over the course of the weeks. And so, in this way, we know that they are working on their own internal clocks, rather than somehow sensing the day outside.

So fine, we have a body clock, and it turns out that it's incredibly important in our lives. It's a huge driver for culture, and I think that it's the most underrated force on our behavior. We evolved as a species near the equator, and so we're very well-equipped to deal with 12 hours of daylight and 12 hours of darkness. But of course, we've spread to every corner of the globe, and in Arctic Canada, where I live, we have perpetual daylight in summer and 24 hours of darkness in winter. So the culture, the northern aboriginal culture, traditionally has been highly seasonal. In winter, there's a lot of sleeping going on. You enjoy your family life inside. And in summer, it's almost manic hunting and working activity very long hours, very active.

So, what would our natural rhythm look like? What would our sleeping patterns be in the sort of ideal sense? Well, it turns out that, when people are living without any sort of artificial light at all, they sleep twice every night. They go to bed around 8:00 pm. until midnight and then again, they sleep from about 2:00 am until sunrise. And in-between, they have a couple of hours of sort of meditative quiet in bed. And during this time, there's a surge of prolactin, the likes of which a modern day never sees. The people in these studies report feeling so awake during the daytime, that they realize they're experiencing true wakefulness for the first time in their lives.

So, cut to the modern day. We're living in a culture of jet lag, global travel, 24-hour business, shift work. And, you know, our modern ways of doing things have their advantages, but I believe we should understand the costs.

Thank you.

(Applause)