This is a thousand-year-old drawing of the brain. It's a diagram of the visual system. And some things look very familiar today. Two eyes at the bottom, optic nerve flowing out from the back. There's a very large nose that doesn't seem to be connected to anything in particular.
这是一张一千年前关于大脑的绘画 一个关于视觉系统的图像 有些东西在今天看来也很熟悉 底下是两只眼睛,视觉神经从它们后面伸出来 这是个很大的鼻子 看起来它并没有连接到特殊的部位
And if we compare this to more recent representations of the visual system, you'll see that things have gotten substantially more complicated over the intervening thousand years. And that's because today we can see what's inside of the brain, rather than just looking at its overall shape.
如果我们把这个 跟最近的视觉系统的表现形式进行对比 你会发现情况变得异常复杂 在经历了几千年之后 这是因为今天我们可以看见大脑里面的东西 而不只是它大致的形状
Imagine you wanted to understand how a computer works and all you could see was a keyboard, a mouse, a screen. You really would be kind of out of luck. You want to be able to open it up, crack it open, look at the wiring inside. And up until a little more than a century ago, nobody was able to do that with the brain. Nobody had had a glimpse of the brain's wiring.
想象下如果你想知道电脑是如何工作的 你能看到的只是键盘,鼠标和屏幕 你真的不会那么走运(明白它是怎么工作的) 你会想要打开它,拆开它 看看里面电线的连接 直到一百多年以前 没有人能够这样对待大脑 没人看到过大脑的回路
And that's because if you take a brain out of the skull and you cut a thin slice of it, put it under even a very powerful microscope, there's nothing there. It's gray, formless. There's no structure. It won't tell you anything.
那是因为如果你把大脑从头盖骨里拿出来 从中切出一个薄片 把它放在即便很强大的显微镜下面 那里什么都没有 它是灰色的,没有固定形状 没有结构。它不会告诉你任何东西
And this all changed in the late 19th century. Suddenly, new chemical stains for brain tissue were developed and they gave us our first glimpses at brain wiring. The computer was cracked open.
这些都在19世纪末发生了改变 忽然间,人们发明了新的大脑组织的化学染料 这些染料让我们第一次看到大脑的回路 这个电脑被打开了
So what really launched modern neuroscience was a stain called the Golgi stain. And it works in a very particular way. Instead of staining all of the cells inside of a tissue, it somehow only stains about one percent of them. It clears the forest, reveals the trees inside. If everything had been labeled, nothing would have been visible. So somehow it shows what's there.
真正开启现代神经科学的是 一种叫高尔基染色法的染料 它工作原理很特别 它并不是对组织里面的所有细胞进行染色 而是只染对其中大约1%的细胞 它清除了森林的图像,展现了其中的树木 如果所有东西都被标记上的话,那什么都看不见了 所有它以某种方式展示了大脑里的东西
Spanish neuroanatomist Santiago Ramon y Cajal, who's widely considered the father of modern neuroscience, applied this Golgi stain, which yields data which looks like this, and really gave us the modern notion of the nerve cell, the neuron. And if you're thinking of the brain as a computer, this is the transistor. And very quickly Cajal realized that neurons don't operate alone, but rather make connections with others that form circuits just like in a computer. Today, a century later, when researchers want to visualize neurons, they light them up from the inside rather than darkening them. And there's several ways of doing this. But one of the most popular ones involves green fluorescent protein. Now green fluorescent protein, which oddly enough comes from a bioluminescent jellyfish, is very useful. Because if you can get the gene for green fluorescent protein and deliver it to a cell, that cell will glow green -- or any of the many variants now of green fluorescent protein, you get a cell to glow many different colors.
西班牙神经解剖学家圣地亚哥·拉蒙-卡哈尔 被普遍认为是现代神经科学之父 他用高尔基染色法展示了这样的图像 这给了我们神经细胞,神经元的现代概念 如果你把大脑想象成一个电脑 这就是晶体管 卡哈尔很快意识到 神经元不是单独工作的 而是与其它神经元互相连接 形成像电脑一样的电路 今天,一个世纪之后,当研究人员想要看神经元的时候 他们从内部点亮神经元,而不是让它们变暗 它有几种做法 最流行的做法之一 要用到荧光蛋白 现在,绿色荧光蛋白 一种来自生物发光的水母中的荧光蛋白 很有用处 因为如果你能得到绿色荧光蛋白的基因 并把它运入一个细胞 那个细胞就会发出绿色荧光—— 如果你使用任何这种绿色荧光蛋白的变体 你可以让一个细胞发出不同的颜色的荧光
And so coming back to the brain, this is from a genetically engineered mouse called "Brainbow." And it's so called, of course, because all of these neurons are glowing different colors.
回到大脑的话题 有一种叫“大脑彩虹”的转基因小鼠 人们这样叫它 当然是因为这些神经元在发出不同颜色的荧光
Now sometimes neuroscientists need to identify individual molecular components of neurons, molecules, rather than the entire cell. And there's several ways of doing this, but one of the most popular ones involves using antibodies. And you're familiar, of course, with antibodies as the henchmen of the immune system. But it turns out that they're so useful to the immune system because they can recognize specific molecules, like, for example, the coat protein of a virus that's invading the body. And researchers have used this fact in order to recognize specific molecules inside of the brain, recognize specific substructures of the cell and identify them individually.
现在,神经科学家们有时候需要识别 神经元的特定分子元件 识别分子,而不是整个细胞 这可以通过好几种方法做到 但是最流行的方法之一 用到了抗体 你们一定 对作为免疫系统的抗体十分熟悉 实际上它们在免疫系统中如此重要的原因是 它们可以识别特定的分子 比如一个入侵身体的病毒的 外壳蛋白 研究人员利用抗体的这个特性 来识别大脑内部的特定分子 识别细胞的特定亚结构 并将它们逐个分辨出来
And a lot of the images I've been showing you here are very beautiful, but they're also very powerful. They have great explanatory power. This, for example, is an antibody staining against serotonin transporters in a slice of mouse brain.
我在这展示的很多图像都很漂亮 但它们同时也很强大 它们可以解释很多东西 比如说,这是一个 针对小鼠大脑切片里5-羟色胺转运体的抗体染色图象
And you've heard of serotonin, of course, in the context of diseases like depression and anxiety. You've heard of SSRIs, which are drugs that are used to treat these diseases. And in order to understand how serotonin works, it's critical to understand where the serontonin machinery is. And antibody stainings like this one can be used to understand that sort of question.
你们肯定听说过5-羟色胺 它与忧虑、焦虑一类的疾病有关 你们也听说过 SSRIs (选择性5-羟色胺再摄取抑制剂) 它被用来治疗以上几种疾病 如果想了解5-羟色胺是怎么起作用的 我们必须先明白5-羟色胺作用的部位在哪里 而我们可以通过这样的抗体染色 来解答类似的问题
I'd like to leave you with the following thought: Green fluorescent protein and antibodies are both totally natural products at the get-go. They were evolved by nature in order to get a jellyfish to glow green for whatever reason, or in order to detect the coat protein of an invading virus, for example. And only much later did scientists come onto the scene and say, "Hey, these are tools, these are functions that we could use in our own research tool palette." And instead of applying feeble human minds to designing these tools from scratch, there were these ready-made solutions right out there in nature developed and refined steadily for millions of years by the greatest engineer of all. Thank you. (Applause)
我想给你们留下这样一个信息: 绿色荧光蛋白和抗体 最早都是自然产物 它们通过自然进化 以便使一个水母不论以什么原因发出绿色荧光 或是以便识别入侵身体的病毒的外壳蛋白 过了很久很久以后,科学家才出场 说:“这些都是工具, 我们可以把这些功能 用到我们自己的研究工具控制板上。” 与其用有限的人类智慧 来从头设计工具 不如用这些在自然界中 经过几百万年的发展、改善并稳定下来的现成的工具来解答 它们是大自然的鬼斧神工 谢谢 (掌声)