要点：你的大脑如何运作并解读世界 | 大卫·伯森博士

欢迎来到《赫伯曼实验室精华》，我们将重温往期节目，为您带来最有效、最具实操性的科学工具，助力心理健康、身体健康与表现提升。我是安德鲁·赫伯曼，斯坦福医学院神经生物学与眼科学教授。现在，我将与大卫·伯森博士展开对话。二十多年来，您始终是我在神经系统领域的权威顾问——关于它的运作机制与结构体系。

Welcome to Huberman Lab Essentials, where we revisit past episodes for the most potent and actionable science based tools for mental health, physical health, and performance. I'm Andrew Huberman, and I'm a professor of neurobiology and ophthalmology at Stanford School of Medicine. And now for my discussion with Doctor. David Berson. For more than twenty years, you've been my go to source for all things nervous system, how it works, how it's structured.

今天我想就此请教您几个问题。相信通过了解这部让我们思考、感受、观察的精密机器，大家会受益匪浅。能否请您解释视觉形成的原理？当光子进入眼睛后会发生什么？

So today I want to ask you some questions about that. I think people would gain a lot of insight into this machine that makes them think and feel and see, etcetera. If you would, could you tell us how we see? A photon of light enters the eye, what happens? Right.

比如我望向窗外看见卡车驶过，或者看着墙上爱犬的照片——这些视觉现象是如何实现的？

I mean, how is it that I look outside, I see a truck drive by, or I look on the wall, I see a photo of my dog. How does that work? Right, so this

这显然是个古老命题。归根结底，视觉体验源于大脑对外周输入信号产生的特定活动模式。但即便没有外周输入，你仍能产生视觉体验——梦境中看到的景象并非来自眼睛。那些是记忆吗？

is an old question, obviously. And clearly in the end, the reason you have a visual experience is that your brain has got some pattern of activity that associates with the input from the periphery. But you can have a visual experience with no input from the periphery as well. When you're dreaming, you're seeing things that aren't coming through your eyes. Are those memories?

某种程度上可以说它们反映了你的视觉经验，但未必是具体记忆（当然也可能是）。关键在于，视觉体验本质是大脑现象。不过正常情况下，我们通过眼睛观察世界形成视觉。当我们注视外部世界时，视网膜向大脑传递的信息才是关键。

I would say in a sense, they may reflect your visual experience. They're not necessarily specific visual memories, but of course they can be. But the point is that the experience of seeing is actually a brain phenomenon. But of course, under normal circumstances, we see the world because we're looking at it and we're using our eyes to look at it. And fundamentally, when we're looking at the exterior world, it's what the retina is telling the brain that matters.

视网膜中有种称为神经节细胞的神经元，它们是眼脑沟通的核心媒介。眼睛如同相机，负责捕捉初始图像并进行初步处理，随后将信号传输至大脑皮层——正是这个区域让我们产生有意识的视觉体验。当然，大脑其他区域也会接收视觉信息并进行不同处理。

So there are cells called ganglion cells. These are neurons that are the key cells for communicating between eye and brain. The eye is like the camera, it's detecting the initial image, doing some initial processing, and then that signal gets sent back to the brain proper. And of course, it's there at the level of the cortex that we have this conscious visual experience. There are many other places in the brain that get visual input as well doing other things with that kind of information.

我经常收到关于色觉的疑问。您能否解释人类如何感知红色、绿色、蓝色等色彩？

So I get a lot of questions about color vision. If you would, could you explain how is it that we can perceive reds and greens and blues and things of that sort?

没错，关于光的首要理解是它只是电磁辐射的一种形式。它在振动，在振荡，

Right, so the first thing to understand about light is that it's just a form of electromagnetic radiation. It's vibrating, it's oscillating,

当你说它在振动、在振荡时，是指光子实际上在移动吗？嗯，从某种

When you say it's vibrating, it's oscillating, you mean that photons are actually moving? Well, in a

意义上说，光子确实在空间中移动。我们将光子视为粒子，这是理解光的一种方式，但我们也可以将其视为波，就像无线电波一样，两种理解都成立。无线电波具有频率，就像收音机调频盘上的频率，而电磁频谱中某些特定频率能被视网膜中的神经元检测到。这些就是我们所见之物，但可见光范围内仍存在不同波长。这些不同波长在某种程度上被神经系统解析或解码，从而形成我们对色彩的感知。

sense, photons are, they're certainly moving through space. We think about photons as particles, and that's one way of thinking about light, but we can also think of it as a wave, like a radio wave, either way is acceptable. And the radio waves have frequencies like the frequencies on your radio dial, and certain frequencies in the electromagnetic spectrum can be detected by neurons in the retina. Those are the things we see, but there's still different wavelengths within the light that can be seen by the eye. And those different wavelengths are unpacked in a sense or decoded by the nervous system to lead to our experience of color.

本质上，不同波长通过专门对不同波长光敏感的不同神经元，带给我们不同颜色的感觉。

Essentially different wavelengths give us the sensation of different colors through the auspices of different neurons that are tuned to different wavelengths of light.

所以当少量光线进入我的眼睛时，感光细胞会将其转化为电信号。那么，特定光子最终是如何让我产生红色、绿色或蓝色等不同色觉的呢？

So when a little bit of light hits my eye goes in, the photoreceptors convert that into electrical signal. Right. How is it that a given photon of light gives me the perception, eventually at least the perception of red versus green versus blue.

是的。想象在视网膜的第一层——这里发生着从电磁辐射到神经信号的转换——存在不同类型的敏感细胞，它们表达并制造着不同的内部分子。这些分子的核心功能就是吸收光子，这是视觉过程的第一步。实际上，典型视网膜中我们需要关注约五种这类蛋白质，但对于色彩视觉，关键只有三种。

Right. So if you imagine that in the first layer of the retina where this transformation occurs from electromagnetic radiation into neural signals, that you have different kinds of sensitive cells that are expressing, they're making different molecules within themselves. Fourth is express purpose of absorbing photons, which is the first step in the process of seeing. Now it turns out that altogether, there are about five proteins like this that we need to think about in the typical retina. But for seeing color, really it's three of them.

这三种不同蛋白质各自偏好吸收不同频率的光。随后神经系统追踪这些信号，通过对比分析来解读光的波长组成。因此当你眺望风景时能判断'天色已晚，万物泛金'，这完全归功于我们吸收外界光线，并因抵达眼睛的光线成分差异而通过大脑进行解读的功能。

So there are three different proteins, each absorbs light with a different preferred frequency. And then the nervous system keeps track of those signals, compares and contrast them to extract some understanding of the wavelength composition of light. So you can see just by looking at a landscape, oh, it must be late in the day because things are looking golden. That's all a function of our absorbing the light that's coming from the world and interpreting that with our brain because of the different composition of the light that's reaching our eyes.

是否可以合理假设，我对红色的感知与你对红色的感知是相同的？

Is it fair to assume that my perception of red is the same as your perception of red?

嗯，这是个很好的问题。

Well, that's a great question.

而且我的更好。开个玩笑。

And that mine is better. I'm kidding.

这是个深刻的问题，一个深奥的哲学问题。这个问题可能最终无法通过常规的实证科学方法解答，因为它本质上关乎个体体验。我们能说的是，例如，我们认为对颜色视觉至关重要的生物机制，在不同个体间——无论是人类还是其他动物——似乎高度相似。因此，我们认为生理过程在前端看起来非常相似。

It's a great question. It's a deep philosophical question. It's a question that really probably can't even ultimately be answered by the usual empirical scientific processes, because it's really about an individual's experience. What we can say is that the biological mechanisms that we think are important for seeing color, for example, seem to be very highly similar from one individual to the next, whether it be human beings or other animals. And so we think that the physiological process looks very similar on the front end.

但一旦涉及到感知、理解或体验层面，这就有点难以用我们研究生物视觉的科学方法来精确描述了。

But once you're at the level of perception or understanding or experience, that's something that's a little bit tougher to nail down with the sorts of scientific approaches that we approach biological vision with, let's say.

我们早就知道有些方法可以改善睡眠，包括服用苏糖酸镁、茶氨酸、洋甘菊提取物和甘氨酸，以及藏红花和缬草根等较冷门的成分。这些都是临床验证的成分，能帮助你入睡、保持睡眠，并醒来时感觉更清爽。我很高兴地告诉大家，我们的长期赞助商AG1刚刚推出了一款新产品AGZ，这是一种夜间饮品，旨在帮助你获得更好的睡眠，醒来时感觉超级精神。过去几年里，我与AG1团队合作开发了这个新配方。

We've known for a long time that there are things that we can do to improve our sleep. And that includes things that we can take things like magnesium threonate, theanine, chamomile extract, and glycine, along with lesser known things like saffron and valerian root. These are all clinically supported ingredients that can help you fall asleep, stay asleep, and wake up feeling more refreshed. I'm excited to share that our longtime sponsor AG1 just created a new product called AGZ, a nightly drink designed to help you get better sleep and have you wake up feeling super refreshed. Over the past few years, I've worked with the team at AG1 to help create this new AGZ formula.

它以精确的比例包含了最佳助眠成分，调配成一种易于饮用的混合物。这消除了在众多助眠补充剂中筛选、确定合适剂量和选择适合自己产品的所有复杂性。据我所知，AGZ是市场上最全面的睡眠补充剂。我在睡前30到60分钟服用它，顺便说一句，味道很棒。

It has the best sleep supporting compounds in exactly the right ratios in one easy to drink mix. This removes all the complexity of trying to forge the vast landscape of supplements focused on sleep and figuring out the right dosages and which ones to take for you. AGZ is to my knowledge, the most comprehensive sleep supplement on the market. I take it thirty to sixty minutes before sleep. It's delicious by the way.

它显著提升了我睡眠的质量和深度。这一点既来自我主观的睡眠感受，也通过睡眠监测数据得到验证。我很期待大家尝试这款新AGZ配方，享受更好睡眠带来的益处。AGZ现有巧克力、薄荷巧克力和混合莓果三种口味。正如我之前提到的，它们都极其美味。

And it dramatically increases both the quality and the depth of my sleep. I know that both from my subjective experience of my sleep and because I track my sleep. I'm excited for everyone to try this new AGZ formulation and to enjoy the benefits of better sleep. AGZ is available in chocolate, chocolate mint, and mixed berry flavors. And as I mentioned before, they're all extremely delicious.

三种口味中我最喜欢的大概是薄荷巧克力，但其实每种都很棒。若想尝试AGZ，请访问drinkagz.com/huberman获取专属优惠。再次提醒，网址是drinkagz.com/huberman。你刚才提到本质上存在五种视锥细胞类型，这些细胞负责吸收不同波长的光线。

My favorite of the three has to be, I think chocolate mint, but I really like them all. If you'd like to try AGZ, go to drinkagz.com/huberman to get a special offer. Again, that's drinkagz.com/huberman. You mentioned that there are five different cone types essentially, cones being the cells that absorb light of different wavelengths.

严格来说不是五种视锥细胞，实际只有三种。观察色觉工作原理时，你会发现必须存在三种不同的信号传导。还有几种其他类型的感光色素，其中一种主要负责暗视觉——当你在无月之夜借助微光视物时，起作用的是视杆细胞及其专属色素。

It's not really five types of cones, there are really three types of cones. And if you look at the way that color vision is thought to work, you can sort of see that it has to be three different signals. There are a couple of other types of pigments. One is really mostly for dim light vision. When you're walking around in a moonless night and you're seeing things with very low light, that's the rod cell and that uses its own pigment.

此外还有一类我们稍后可能会讨论的色素——黑视蛋白色素。

And then there's another class of pigments we'll probably talk about a little bit later, this melanopsin pigment.

我还以为你指的是紫外线或红外线这类光谱呢

I thought you were referring to like ultraviolet and infrared and things Right, of that

以典型人类为例——这么说吧，我们大多数人拥有三种视锥细胞，因此能感知相应色彩。而包括猫狗在内的大多数哺乳动物只有两种视锥细胞，这限制了它们在波长（即我们所说的颜色）领域的视觉能力。

so in the case of a typical, well, let's put it this way, in human beings, most of us have three cone types and we can see colors that stem from that. In most mammals, including your dog or your cat, there really are only two cone types and that limits the kind of vision that they can have in the domain of wavelength or color as we'd say.

我们来聊聊那种特殊的光敏色素吧。

Let's talk about that odd photo pigment.

是的，这最后一种色素非常奇特。你可以把它视为一个系统中最初的敏感元件，这个系统旨在告诉你的大脑周围世界的亮度。而它最特别之处在于，从某种意义上说，它位于错误的位置。当你想象视网膜的结构时，本质上就像千层蛋糕。你的眼球后部有一层薄膜，但实际上它是由许多薄层堆叠而成。

Yeah, so this last pigment is a really peculiar one. One can think about it as really the initial sensitive element in a system that's designed to tell your brain about how bright things are in your world. And the thing that's really peculiar about this pigment is that it's in the wrong place in a sense. When you think about the structure of the retina, you think about a layer cake essentially. You've got this thin membrane at the back of your eye, but it's actually a stack of thin layers.

这些薄层的最外层就是你们之前提到的感光细胞所在之处。那里本质上就是你相机的胶片所在。光子在那里与感光色素发生神奇作用，将其转化为神经信号。

And the outermost of those layers is where these photoreceptors you were talking about earlier are sitting. That's where the film of your camera is essentially. That's where the photons do their magic with the photopigments and turn it into a neural signal.

这个比喻很好。我从未真正将感光细胞想象成相机的胶片，但这样解释很合理。

I like that. I've never really thought of the photoreceptors as the film of the camera, but that makes sense.

这是光线通过眼睛光学系统成像的表面。现在你有一组传感器阵列在捕捉这些信息，本质上创建了一个位图。但这些信息现在是以神经信号的形式分布在视网膜表面。然而我们发现，这最后一种感光色素位于视网膜的另一端，最内层，也就是所谓的神经节细胞所在之处。这些是与大脑对话的细胞，能够直接将感光细胞传来的信息进行传递。

It's the surface on which the light pattern is imaged by the optics of the eye. And now you've got an array of sensors that's capturing that information and creating a bitmap essentially. But now it's in neural signals distributed across the surface of the retina. But it turns out that this last photo pigment is in the other end of the retina, the innermost part of the retina, that's where the so called ganglion cells are. Those are the cells that talk to the brain, the ones that actually can communicate directly what information comes to them from the photoreceptors.

而在这里，我们发现一些输出神经元——我们原本认为它们不应该直接对光敏感——实际上正在制造这种感光色素，吸收光线并将其转化为神经信号发送给大脑。这就是你的昼夜节律系统，它负责计时，完全内置于我们的生物机制中。这实际上是视网膜失明患者经常抱怨的问题之一——失眠

And here, you've got a case where actually some of the output neurons that we didn't think had any business being directly sensitive to light, we're actually making this photo pigment, absorbing light and converting that to neural signals and sending it to the brain. That's your circadian system, it's keeping time and it's all built into our biology. And this is actually one of the things that blind patients often complain about if they've got retinal blindness is insomnia

因为他们的大脑在半夜

because their brains are awake in the middle

还醒着。没错，他们失去了同步。他们的生物钟还在运转，但逐渐失去同步，因为人类的生物钟周期大约是24.2小时或23.8小时，会一点点产生偏差。所以你需要同步信号，否则就无法确认日出日落的时间——而这正是你需要与之同步的基准。

of the night. Exactly, they're not synchronized. Their clock is there, but they're drifting out of phase because their clock's only good to twenty four point two hours or twenty three point eight hours, little by little they're drifting. So you need a synchronization signal because otherwise you have nothing to actually confirm when the rising and the setting of the sun is, that's what you're trying to synchronize yourself to.

我对生物钟非常着迷，尤其是我们体内所有细胞都内置了一个大约24小时的时钟。但我从未真正了解过这个时钟本身如何运作，以及它如何向身体其他部分发出信号——比如肝脏何时该执行某项功能，胃部何时该进行另一项活动。能否请您简要描述一下这个时钟的位置、功能，以及它如何向细胞传递指令的大致机制？

I'm fascinated by the circadian clock and the fact that all the cells of our body have essentially a twenty four hour ish clock in them. Right. I've never really heard it described how the clock itself works and how the clock signals to all the rest of the body when, you know, the liver should be doing one thing and when the stomach should be doing another. If you would just maybe briefly describe where the clock is, what it does, and some of the top contour of how it tells the cells of

没错，首先要说明的是，正如你所说，生物钟遍布全身。大多数组织都有自己的时钟。而昼夜节律系统的中央起搏器作用就是协调所有这些时钟。在大脑中有一个微小的神经核团——视交叉上核（SCN）。

the body what to do. Right, so the first thing to say is that, as you said, the clock is all over the place. Most of the tissues in your body have clocks. The role of the central pacemaker for the circadian system is to coordinate all of these. There's a little nucleus, a little collection of nerve cells in your brain.

它位于下丘脑，这个位置在神经系统结构中很特殊，能直接接收视网膜输入信号。你可以把下丘脑想象成驱动行为的超级协调器，也是...

It's called the suprachiasmatic nucleus, the SCN. And it is sitting in a funny place for the rest of the structures in the nervous system that get direct retinal input. It's sitting in the hypothalamus, which you can think about as sort of the great coordinator of drives and The source of

我们所有快乐和烦恼的源头。或者说大部分烦恼的来源。

all our pleasures and all our problems. Right. Or most of our problems.

确实如此。它深藏在大脑内部，驱动着你的行为——当你感到寒冷时会穿上外套、发抖，这些反应都由下丘脑协调。我们讨论的这条从视网膜出发的神经通路，那些编码光强度的特殊细胞直接将信号传递到这个被自主神经系统和内分泌系统控制中心包围的区域。下丘脑运用所有手段调控全身。

Yes, it really is. But it's sort of deep in your brain, things that drive you to do things. If you're freezing cold, you put on a coat, you shivery, all these things are coordinated by the hypothalamus. So this pathway that we're talking about from the retina and from these peculiar cells that are encoding light intensity are sending signals directly into a center that's surrounded by all of these centers that control autonomic nervous system and your hormonal systems. The hypothalamus uses everything to control the rest of the bodies.

视交叉上核这个昼夜节律中枢也是如此。它能同时影响自主神经系统、体液系统，当然还包括...

And that's true, the suprachiasmatic nucleus, this circadian center as well. It can get its fingers into the autonomic nervous system, the humeral system, and of course, up to the centers of

负责组织协调理性行为的高级脑区。那么我的理解是：视交叉上核这组细胞拥有24小时节律，这个节律通过眼睛的特殊神经元与外界环境保持同步。然后主时钟SCN通过释放体液信号影响全身各处，您还提到它会作用于自主神经系统——这个系统大致调控着我们的警觉程度、平静状态，乃至思维和认知功能。

the brain that organize coordinated rational behavior. So if I understand correctly, we have this group of cells, the suprachiasmatic nucleus, it's got a twenty four hour rhythm. That rhythm is more or less matched to what's going on in our external world by the specialized set of neurons in our eye. But then the master clock itself, the SCN releases things in the blood humoral signals that go out various places in the body. And then you said to the autonomic system, which is regulating more or less how alert or calm we are, as well as our thinking and our cognition.

当然。那么视交叉上核（SCN）可以通过松果体影响褪黑激素系统。

Sure. Then the SCN, the suprachiasmatic nucleus can impact the melatonin system via the pineal.

没错，这种现象表现为：如果你能每小时测量一次褪黑激素水平，你会发现白天时它非常低，夜晚则非常高。但如果你半夜起床去洗手间并打开明亮的荧光灯，你的褪黑激素水平会骤降至最低。光线正通过我们刚描述的机制直接影响你的荷尔蒙水平。这是光线作用于你荷尔蒙状态的途径之一，完全超出你通常的认知范围，对吧？你当时可能只想着洗手间里的东西，比如牙刷、牙膏管。

Right, the way this is seen is that if you were to measure your melatonin level over the course of the day, if you could do this hour by hour, you'd see that it's really low during the day, very high at night. But if you get up in the middle of the night and go to the bathroom and turn on bright fluorescent light, your melatonin level is slammed to the floor. Light is directly impacting your hormonal levels through this mechanism that we just described. So this is one of the routes by which light can act on your hormonal status through pathways that are completely beyond what you normally would think about, right? You're thinking about the things in the bathroom, oh, there's the toothbrush, there's the tube of toothpaste.

但与此同时，这个系统只是在计算光子并发出信号：‘哇，现在有大量光子，让我们停止释放褪黑激素。’

But meanwhile, this other system is just counting photons and saying, Oh, wow, there's a lot of photons right now. Let's shut down the melatonin release.

现在我想请教你关于视觉系统的另一个方面，即与我们平衡感相关的部分。或许我们可以从最简单的视觉前庭层（所谓的平衡系统）开始讲解，然后逐步拼凑整个系统以便大家理解。此外，我们还应该提供一些工具，帮助人们在前庭系统失调时缓解恶心感。

I want to ask you about a different aspect of the visual system now, which is the one that relates to our sense of balance. Maybe just walk in at the simplest layers of vision vestibular, so called balance system, and then maybe we can piece the system together for people so that they can understand. And then also we should give them some tools for adjusting their nausea when their vestibular system is out of whack.

好的。首先需要理解的是，前庭系统的设计初衷是让你感知自己在空间中的运动状态。举个例子，如果我们只是坐在汽车的副驾驶位置，当司机踩下油门开始前进时，你能感觉到这种移动。即使闭着眼睛也能感知，就算耳朵被堵住且闭着眼睛，你依然能知道。

Cool. So, I mean, the first thing to think about is that the vestibular system is designed to allow you to sense how you're moving in the world, through the world. Basically, idea is that if we're just sitting in a car in the passenger seat and the driver hits the accelerator and you start moving forward, you sense that. If your eyes were closed, you'd sense it. If your ears were plugged and your eyes were closed, you'd still know it.

任何将你从当前位置颠簸移位的动作，基本上都会被前庭系统检测到。它位于你的内耳中，那些毛细胞表面竖立着纤毛。根据你弯曲它们的方向，这些细胞会被抑制或兴奋，然后它们通过类似神经元的过程与神经元交流，信号就这样传递出去。如果你感知到耳蜗内有东西在弹跳，这时你就接收到了听觉信号——

Anything that jostles you out of the current position you're in right now will be detected by the vestibular system pretty much. It's basically in your inner ear, hairy cells, they got little cilia sticking up off the surfaces. And depending on which way you bend those, the cells will either be inhibited or excited, but then they talk to neurons with a neuron like process and off you go. Now you've got an auditory signal if you're sensing things bouncing around in your cochlea, which is-

从某种角度来说是这样。

In some ways.

同理，你的耳膜振动，与世界上声波的振动产生共鸣。但在前庭系统的情况下，进化构建了一个检测液体流过那些毛细胞运动的系统。如果你将这样的传感器置于充满液体的管道中，当你绕管道中心轴线旋转时，这个传感器就会被激活。

Sympathetically the bouncing of your eardrum, which is in sympathetically the sound waves in the world. But in the case of the vestibular apparatus, evolution has built a system that detects the motion of say fluid going by those hairs. And if you put a sensor like that in a tube that's fluid filled, now you've got a sensor that will be activated when you rotate that tube around the axis that passes through the middle of it.

我总把它想象成三个呼啦圈。

I always think of it as three hula hoops.

对，三个呼啦圈。

Right, three hula hoops.

一个直立，一个平放在地上。对，另一个，再换个方向。

One standing up, one lying down on the ground. Right, other one. One the other way.

三个方向。所以就像角落里的那样，有三个编码轴

Three directions. So three axes of encoding, just like in the corners The of the

不，然后我总说这是，然后是小狗歪头的动作。

no, and then I always say it's, and then the puppy head tilt.

没错，小狗歪头，那是另一个。关键在于，你的大脑最终能解析这些传感器告诉你头部刚做了怎样的旋转。现在你能判断头部是左右还是上下转动。这是传回大脑的感觉信号，确认你刚做了某个动作。这些大多发生在你意识表层之下。

Yeah, puppy head tilt, that's the other one. So the point is that your brain is eventually going to be able to unpack what these sensors are telling you about how you just rotated your head. Now you can tell if you're rotating your head left or right, up or down. That's the sensory signal coming back into your brain confirming that you've just made a movement that you will. A lot of this is happening under the surface of what you're thinking.

这些都是反射动作。理解这两个系统如何协同工作的最佳方式，或许是想象你突然将头向左转时的情形。当你突然左转头时，眼睛实际上会向右转动。即使在完全黑暗的环境中，你也会自动完成这个动作。如果用红外摄像机观察，你会发现自己在伸手不见五指的环境里依然如此。

These are reflexes. Maybe the best way to think about how these two systems work together is to think about what happens when you suddenly rotate your head to the left. When you suddenly rotate your head to the left, your eyes are actually rotating to the right. Automatically, you do this in complete darkness. If you had an infrared camera and watched yourself in complete darkness, you can't see anything.

当你向左转头时，眼睛会向右转动。这是前庭系统在运作，它试图补偿头部旋转，使视线保持固定方向。大脑会极力维持视网膜上世界影像的稳定性。当然，由于你本身在移动，不可能完全稳定所有画面。但稳定性维持得越好，视觉体验就越清晰。

You're rotating your head to the left, your eyes would rotate to the right. That's your vestibular system saying, I'm going to try to compensate for the head rotation so my eyes are still looking in the same place. So the brain works really hard to mostly stabilize the image of the world on your retina. Now of course, you're moving through the world, so you can't stabilize everything. But the more you can stabilize most of the time, the better you can see.

这就是为什么当我们扫视场景时，会进行短暂而快速的眼球运动然后停顿。不仅人类如此，观察人行道上的鸽子就会发现它们会做出滑稽的点头动作——实际上是在身体前移时将头部后仰，以此保持视觉世界的影像静止。真的吗？

And that's why when we're scanning a scene, looking around at things, we're making very rapid eye movements for very short periods of time and then we just rest. But we're not the only ones that do that. If you ever watch a pigeon walking on the sidewalk, it does this funny head bobbing thing. But what it's really doing is racking its head back on its neck while its body goes forward so that the image of the visual world stays static. Really?

你应该看过YouTube上那些搞笑的鸡视频吧？抓着鸡上下晃动时，它的头部会保持不动。这些动物都在竭力维持视网膜成像的稳定，只有在必须移动时才快速调整然后重新稳定。所以鸽子才会后仰头部？

And you've seen the funny chicken videos on YouTube, right? You've taken a chicken, move it up and down and It's stays in one all the same thing. All of these animals are trying hard to keep the image of the world stable on their retina as much of the time as they possibly can. And then when they've got to move, make it fast, make it quick, and then stabilize again. That's why the pigeons have their head back?

没错，确实如此。哇，我是说...

It is, yeah. Wow. Mean, if

也许我需要稍作停顿消化这些惊人的信息。现在请允许我插播感谢赞助商Function。去年在寻找最全面的实验室检测方案时，我成为了Function会员。他们提供100多项高级检测，能全面反映身体健康状况，包括心脏健康、激素水平、免疫功能、营养状态等重要指标。

you- Maybe I just need to pause there for a second and digest that, amazing. I'd like to take a quick break and acknowledge one of our sponsors Function. Last year, became a Function member after searching for the most comprehensive approach to lab testing. Function provides over 100 advanced lab tests that give you a key snapshot of your entire bodily health. This snapshot offers you with insights on your heart health, hormone health, immune functioning, nutrient levels, and much more.

Function不仅检测100多种关乎身心健康的关键生物标记物，还由领域顶尖医生分析结果并提供专业建议。比如我的首次检测就发现血汞超标，他们不仅诊断出问题，还指导我通过减少金枪鱼摄入、增加绿叶蔬菜、补充NAC和乙酰半胱氨酸（两者都能促进谷胱甘肽生成和排毒）来降低汞含量。后续复检证实这个方法确实有效。

Function not only provides testing of over a 100 biomarkers key to your physical and mental health, but it also analyzes these results and provides insights from top doctors who are expert in the relevant areas. For example, in one of my first tests with function, I learned that I had elevated levels of mercury in my blood. Function not only helped me detect that, but offered insights into how best to reduce my mercury levels, which included limiting my tuna consumption. I'd been eating a lot of tuna while also making an effort to eat more leafy greens and supplementing with NAC and acetylcysteine, both of which can support glutathione production and detoxification. And I should say by taking a second function test, that approach worked.

全面的血液检测至关重要。你的心理和生理健康中有许多方面只能通过血液检测才能发现。问题在于血液检测一直非常昂贵且复杂。相比之下，Function的简洁功能和成本水平让我印象深刻，非常亲民。因此，我决定加入他们的科学顾问委员会，并且非常高兴他们赞助了这个播客。

Comprehensive blood testing is vitally important. There's so many things related to your mental and physical health that can only be detected in a blood test. The problem is blood testing has always been very expensive and complicated. In contrast, I've been super impressed by function simplicity and at the level of cost, it is very affordable. As a consequence, I decided to join their scientific advisory board and I'm thrilled that they're sponsoring the podcast.

如果你想尝试Function，可以访问functionhealth.com/huberman。Function目前有超过25万人的等候名单，但他们为Huberman播客听众提供早期访问权限。再次强调，访问functionhealth.com/huberman即可获得Function的早期体验。视觉和平衡系统发生了什么会导致这种恶心感？

If you'd like to try Function, you can go to functionhealth.com/huberman. Function currently has a wait list of over 250,000 people, but they're offering early access to Huberman podcast listeners. Again, that's functionhealth.com/huberman to get early access to function. What's going on with the vision and the balance system that causes a kind of a nausea?

我认为，当你晕动时，根本问题通常是所谓的视觉前庭冲突。你有两个感觉系统向大脑传递你在空间中移动的信息，只要它们一致，你就没事。比如开车时，你的身体感知到你在向前移动，前庭系统感受到车辆的加速，视觉系统看到景物从身边掠过的前进效果。一切都很和谐，对吧？没问题。

I mean, I think the fundamental problem typically when you get motion sick is what they call visual vestibular conflict. That is you have two sensory systems that are talking to your brain about how you're moving through the world and as long as they agree, you're fine. So if you're driving, your body senses that you're moving forward, your vestibular systems is picking up this acceleration of the car and your visual system is seeing the consequences of forward motion in the sweeping of the scene past you. Everything is honky dory, right? No problem.

但当你向前移动却盯着手机时，你的视网膜看到什么？视网膜看到的是屏幕的稳定图像。屏幕上完全没有运动。

But when you are headed forward, but you're looking at your cell phone, what is your retina seeing? Your retina seeing the stable image of the screen. There's absolutely no motion in that screen.

或者运动只是...或者其他某种运动

Or the motion is just Or some other motion

比如看电影、玩游戏或看视频、足球比赛时，画面运动与你身体的实际情况脱节。大脑不喜欢这样。大脑希望所有信息都保持一致。如果不一致，它就会向你抗议。

Or like if a movie or you're a game or you're watching a video, a football game, the motion is uncoupled with what's actually happening to your body. Your brain doesn't like that. Your brain likes everything to be aligned. And if it's not, it's going to complain to you.

通过让我感到恶心来表达抗议。通过...

By making me feel nauseous. By making

让我感到恶心，也许这样你会改变你的行为。

me feel nauseous and maybe you'll change your behavior.

所以你在说我正在受到惩罚。

So you're getting I'm getting punished.

是的，因为设定了这个情况，所以你

Yeah, for setting it up so So you're

你是说这是一种

you're saying it's a

心灵感应般的快速反应，对吧。

psychic flick, right.

通过前庭系统——你会明白的。视觉信息。嗯，或许沿着这条路径再深入一点，视觉输入是与平衡输入相结合的。这种情况发生在哪里？也许你可以给我们讲讲这个被称为小脑的神秘迷你大脑。

By the vestibular- You'll learn. Visuals. Well, maybe marching a little bit further along this pathway, visual input is combined with balance input. Where does that occur? And maybe you could tell us a little bit about this kind of mysterious little mini brain that they call the cerebellum.

小脑，没错。我向学生描述小脑的方式是，它有点像航空旅行中的空中交通控制系统。这个系统非常复杂，高度依赖于精准的信息。它不仅通过你的感觉系统接收各处发生的一切信息，还在监听大脑其他部位那些计算你下一步行动的小中心。小脑在协调和塑造动作方面扮演着至关重要的角色。

Cerebellum, yeah. So, the way I tried to describe the cerebellum to my students is that it serves sort of like the air traffic control system functions in air travel. It's a system that's very complicated and it's really dependent on great information. So it's taking in the information about everything that's happening everywhere, not only through your sensory systems, but it's listening into all the little centers elsewhere in your brain that are computing what you're going to be doing next and so forth. And it really has an important role in coordinating and shaping movements.

但小脑缺失并不会导致瘫痪，因为你仍有运动神经元，仍能与肌肉沟通。你仍保有反射中枢，只是无法再协调自如。输入与输出间的时机可能错位。若尝试学习新运动技能，比如网球的高压发球，你会难以掌握肌肉动作序列和感官反馈，无法在反复练习后精准击球——经过千百次重复才能渐入佳境。因此小脑全程参与运动学习，通过精细调节动作精度来实现目标。

But it's not that you would be paralyzed if your cerebellum was gone because you still have motor neurons, you still have ways to talk to your muscles. You still have reflex centers, but you wouldn't be coordinating things so well anymore. The timing between input and output might be off. Or if you were trying to practice a new athletic move, like an overhead serve in tennis, you'd be just terrible at learning all of the sequences of muscle movements and the feedback from your sensory apparatus that would let you really hit that ball exactly where you wanted to after the nth rep, the thousandth rep or something, you get much better at it. So the cerebellum is all involved in things like motor learning and refining the precisions of movement so that they get you where you want to go.

当你伸手取香槟杯时，既不会碰倒杯子也不会中途停顿——这正是它的专长所在。

If you reach for a glass of champagne that you don't knock it over or stop short. That's what it's good at.

那些小脑选择性受损的人群。

People who have selective damage to the cerebellum.

确实。典型病例如小脑中风或肿瘤患者，他们可能站立不稳。在无扶手电车这类动态场景中，他们难以调整应对车辆微晃。伸手取物时会出现震颤——因过度伸展而后回调，如此反复。这其实是相当常见的神经学现象。

Absolutely. The typical thing would be a patient who has a cerebellar stroke or a tumor, for example, might be not that steady on their feet. The dynamics of the situation you're standing on a street car with no pole to hold onto, they might not be as good at adjusting all of the little movements of the car. There's a kind of tremor that can occur as they're reaching for things because they reach a little too far and then they overcorrect and come back, things like that. So it's very common neurological phenomenon actually.

神经科医生称之为小脑性共济失调。不仅小脑损伤会导致，传导信息至小脑的神经通路或输出结构受损同样会引起。

Cerebellar ataxia is what the neurologists call it. And it can happen not just with cerebellar damage, but damage to the tracks that feed the information into the cerebellum or provide the structure. Exactly, or output from the cerebellum.

所以小脑是整合大量视觉与平衡信息的区域。

And so the cerebellum is where a lot of visual and balance information is combined.

小脑中这个关键区域——从进化角度看最古老的部分之一，绒球，正是视觉与前庭信息汇聚处理前述运动类型的要地。整个图像稳定网络在此运作，学习过程也同步发生。若前庭器官稍有损伤，视觉系统会通过小脑反馈异常，小脑则通过增强前庭系统输出来补偿缺陷。这套纠错机制堪称小脑功能的典型代表，可作用于众多不同领域。

In a very key place in the cerebellum, which is, it's really one of the oldest parts in terms of evolution, flocculus, right? It's a critical place in the cerebellum where visual and vestibular information comes together for recording just the kinds of movements we were talking about. This image stabilizing network, it's all happening there and there's learning happening there as well. So that if your vestibular apparatus is a little bit damaged somehow, your visual system is actually talking to your cerebellum saying there's a problem here, there's an error and your cerebellum is learning to do better by increasing the output of the vestibular system to compensate for whatever that loss was. So it's a little error correction system that's sort of typical of cerebellar function and it can happen in many, many different domains.

这只是发生在该区域的感官运动整合领域之一。

This is just one of the domains of sensory motor integration that takes place there.

我想谈谈一个很少被讨论的大脑区域，那就是中脑。是的。对于那些不了解的人来说，中脑是位于大脑皮层下方的区域。我想我们从未真正定义过皮层，它大致是哺乳动物大脑或人类大脑最外层的那部分。但中脑非常有趣，因为它控制着许多无意识的行为、反射等等。

I want to talk about an area of the brain that is rarely discussed, which is the midbrain. Yeah. And for those that don't know, the midbrain is an area beneath the cortex. I guess we never really defined cortex, it was kind of the outer layers or are the outer layers of the least mammalian brain or human brain. But the midbrain is super interesting because it controls a lot of unconscious stuff, reflexes, etcetera.

所以你能给我们讲讲中脑，讲讲它的功能吗？好的。

So could you please tell us about the midbrain, about what it does? Yeah.

那里有很多组成部分。我认为首先要说的是，如果你在脑海中想象神经系统，你会看到这个巨大的大脑，然后有一根细小的棒状物垂入你的脊柱，也就是脊髓，这是你的视觉印象。你必须想象的是从脊髓开始，逐渐向上进入这个宏伟的大脑，当你进入颅骨时，你会到达一个脊髓略微变粗的小区域。它仍然有那种细长树干的感觉。有点像

So there's a lot of pieces there. I think the first thing to say is if you imagine the nervous system in your mind's eye, you see this big honking brain and then there's this little thin little wand that dangles down into your vertebral column, the spinal cord, and that's kind of your visual impression. What you have to imagine is starting in the spinal cord and working your way up into this big magnificent brain and what you would do as you enter the skull is get into a little place where the spinal cord kind of thickens out. It still has that sort of long skinny trunk like feeling. Sort of like

一个桨或勺子的形状。

a paddle or a spoon shape.

对，它开始稍微扩散开来，这是因为进化在那里塞入了更多有趣的东西来处理信息和产生运动。所以你所说的中脑是颅骨内这种类似脊髓的扩大部分的最后一段，我们称之为脑干。在到达皮层之前，这段的最后部分就是中脑。那里有一个非常重要的视觉中心，叫做上丘，但就解释视觉输入和组织相关行为而言，这里是最活跃的区域。

Right, it starts to spread out a little bit and that's because your evolution has packed more interesting goodies in there for processing information and generating movement. So this midbrain you're talking about is the last bit of this enlarged sort of spinal cordy thing in your skull, which is really the brainstem is what we call it. The last bit of that before you get to this relay up to the cortex is the midbrain. And there's a really important visual center there. It's called the superior colliculus, but this is where most of the action is in terms of interpreting visual input and organizing behavior around that.

你可以把这个脑干区域想象成一个反射中心，它可以重新定向动物的视线、身体，甚至可能是注意力，指向动物周围空间的特定区域。这可能有各种原因。我的意思是，可能有一只捕食者刚刚出现在森林的一个角落，你察觉到了并试图避开它。或者仅仅是任何动作。很多动作，对吧？

You can sort of think about this region of the brainstem is a reflex center that can reorient the animal's gaze or body or maybe even attention to particular regions of space out there around the animal. And that could be for all kinds of reasons. I mean, might be a predator just showed up in one corner of the forest and you pick that up and you're trying to avoid it. Or just any movement. Many movement, right?

当你阅读小说时，可能突然有什么东西溅在页面上，你的眼睛会反射性地看向它。你不需要思考，那是一种反射。但这些是在我们这类大脑进化早期就出现的中心，用于处理对动物在空间上有意义的复杂视觉事件。它在空间中的位置在哪里？事实上，同一个中心还接收来自各种其他感觉系统的输入，这些系统从外部世界的特定位置获取信息，并根据它们对你的重要性，你可能想要避开或接近某些事物。

It might be that suddenly something splats on the page when you're reading a novel and your eye reflexively looks at it. You don't have to think about that, that's a reflex. But these are centers that emerged early in the evolution of brains like ours to handle complicated visual events that have significance for the animal in terms of space. Where is it in space? And in fact, the same center actually gets input from all kinds of other sensory systems that take information from the external world from particular locations and where you might wanna either avoid or approach things according to their significance to you.

所以你会从触觉系统获得输入，也会从听觉系统获得输入。我曾研究过一阵响尾蛇，它们从面部的一些温感器获取输入。这些温感器位于小凹坑中。它们拥有一种额外的感受性感觉系统，即它们使用完全不同的传感器来观察世界。它们使用的传感器与你站在篝火前感受到脸上温暖的传感器相同。

So you get input from the touch system, you get input from the auditory system. I worked for a while in rattlesnakes, they get input from a part of their warm sensors on their face. They're in these little pits. They have a version of an extra receptive sensory system that is they're looking out into the world using a completely different set of sensors. They're using the same sensors that would feel the warmth on your face if you stood in front of a bonfire.

只不过进化赋予了它们这种非常精妙的专门系统，使它们能够成像热源的方位。某种程度上你也可以做到，对吧？如果你围着火堆走动，你可以通过热量打在脸上的感觉来判断火的位置。

Except evolution has given them this very nice specialized system that lets them image where the heat's coming from. You can sort of do that anyway, right? If you walk around the fire, you can feel where the fire is from the heat hitting your face.

那是

Is that the

它们探测猎物的主要方式吗？这是主要方式之一。事实上，它们也使用视觉。它们将这两种系统整合在脑干的顶盖区域。我想

primary way in which they detect prey? It's one of the major ways. And in fact, they use vision as well. And they bring these two systems together in the same place in this tectum region, this brainstem. I want

在这里稍停一下。我认为味觉受体、热传感器、视觉以及所有这些整合最有趣的地方在于，它们确实说明了所有这些感觉神经元都在试图收集信息，并将其塞入一个能够做出有意义决策和行动的系统。而且，信息是来自眼睛、耳朵、鼻子还是脚底其实并不重要，因为最终，它们只是流入的电信号。因此，它们被放置在不同动物的不同位置，取决于该动物的特定需求。对。

to pause here just for one second. I think what's so interesting about taste receptors, heat sensors, and vision and all this integration is that it really speaks to the fact that all these sensory neurons are trying to gather information and stuff it into a system that can make meaningful decisions and actions. And that it really doesn't matter whether or not it's coming from eyes or ears or nose or bottoms of feet, because in the end, it's just electricity flowing in. And so it's placed in different locations on different animals, depending on the particular needs of that animal. Right.

对，所以我可能感觉到脸的一侧有些热，同时闻到烤箱里烤着什么。对。现在，两者都不是特别强烈，但正如你所说，存在某种佐证。

Right, so maybe I'm feeling some heat on one side of my face and I also smell something baking in the oven. Right. So now there's, neither is particularly strong, but as you said, there's some corroboration.

没错。

Right.

而这种验证过程发生在中脑。

And that corroboration is occurring in the midbrain.

对。然后如果你让信息产生冲突，大脑就会困惑，这可能就是你晕动症的来源。所以作为大脑，拥有尽可能多的信息来源是件好事，就像间谍或记者一样，你希望获取尽可能多的外界信息。但如果信息互相矛盾，那就成问题了。对吧？

Right. And then if you throw things into conflict, now the brain is confused and that may be where your motion sickness comes from. So it's great to have, as a brain, it's great to have as many sources of information as you can have, just like if you're a spy or a journalist, you don't want as much information as you can get about what's out there. But if things conflict, that's problematic. Right?

你的消息源对正在发生的事情给出了不同的信息。现在你手上就有个难题了。该发布哪个？

Your sources are giving you different information about what's what's going on. Now you've got a problem on your hands. What do you publish?

我想稍作休息，感谢我们的赞助商Element。Element是一款电解质饮料，包含你所需的一切，不含任何多余成分。这意味着它含有适量比例的电解质——钠、镁和钾，但无糖分。适当的水分补充对大脑和身体功能至关重要。即使是轻微的脱水也会降低认知和身体表现。

I'd like to take a quick break and acknowledge one of our sponsors, Element. Element is an electrolyte drink that has everything you need and nothing you don't. That means the electrolytes, sodium, magnesium, and potassium in the correct amounts, but no sugar. Proper hydration is critical for optimal brain and body function. Even a slight degree of dehydration can diminish cognitive and physical performance.

获取足够的电解质同样重要。钠、镁、钾这些电解质对你体内所有细胞（尤其是神经元或神经细胞）的功能都至关重要。将Element溶解在水中饮用，能轻松确保你获得充足的水分和电解质。为了确保我获得适当的水分和电解质，我早上醒来第一件事就是把一包Element溶解在约16至32盎司的水中饮用。在进行任何体育锻炼时，特别是在大量出汗流失水分和电解质的炎热天气里，我也会饮用Element水溶液。

It's also important that you get adequate electrolytes. The electrolytes, sodium, magnesium, and potassium are vital for functioning of all the cells in your body, especially your neurons or your nerve cells. Drinking Element dissolved in water makes it very easy to ensure that you're getting adequate hydration and adequate electrolytes. To make sure that I'm getting proper amounts of hydration and electrolytes, I dissolve one packet of Element in about sixteen to thirty two ounces of water when I first wake up in the morning, and I drink that basically first thing in the morning. I'll also drink Element dissolved in water during any kind of physical exercise that I'm doing, especially on hot days when I'm sweating a lot and losing water and electrolytes.

Element有多种美味口味。我喜欢树莓味和柑橘味。现在Element还推出了限量版柠檬ade口味，绝对美味。虽然我不想说我最爱哪一种，但这个柠檬ade口味和我最喜欢的树莓味、西瓜味不相上下。真的很难只选一个口味。

Element has a bunch of great tasting flavors. I love the raspberry, I love the citrus flavor. Right now, Element has a limited edition lemonade flavor that is absolutely delicious. I hate to say that I love one more than all the others, but this lemonade flavor is right up there with my favorite other one, which is raspberry or watermelon. Again, I can't pick just one flavor.

我全都喜欢。如果你想尝试Element产品，可以访问drinkelement.com/hubermanspelleddrinklmnt.com/huberman，购买任意Element饮品混合包即可获赠免费样品包。再次提醒，访问drinkelement.com/huberman即可领取免费样品包。这很重要，也完美衔接了我接下来想讨论的话题——基底神经节。这个大脑区域非常有趣，它既会指令我们行动，也会阻止我们行动。

I love them all. If you'd like to try Element, you can go to drinkelement.com/hubermanspelleddrinklmnt.com/huberman, to claim a free Element sample pack with a purchase of any Element drink mix. Again, that's drinkelement.com/huberman to claim a free sample pack. This is important and a great segue for what I'd like to discuss next, is the basal ganglia. This really interesting area of the brain that's involved in instructing us to do things and preventing us from doing things.

没错。基底神经节是什么？它们在控制'执行'和'抑制'行为中主要扮演什么角色？

Right. What are the basal ganglia and what are their primary roles in controlling go type behavior and no go type behavior?

是的，基底神经节位于所谓的前脑深处，属于大脑最高级区域，与皮质功能深度交织。没有基底神经节的协助，大脑皮层无法正常运作，反之亦然。从逻辑上可以这样理解：如果你具备抑制或执行行为的能力，如何决定选择哪个？这就需要大脑皮层为你进行思考判断。

Yeah, so I mean, basal ganglia are sitting deep in what you would call the forebrain. So the highest levels of the brain and it's deeply intertwined with cortical function. The cortex can't really do what it needs to do without the help of the basal ganglia and vice versa. And in a way you can think about this logically is saying, if you have the ability to withhold behavior or to execute it, how do you decide which to do? Well, the cortex is going to have to do that thinking for you.

你必须全面评估所处环境的各种可能性，然后决定：这是个疯狂举动，还是当前明智的投资？我不想...

You have to be looking at all the contingencies of your situation and decide, is this a crazy move or is this a really smart investment right now or what? I don't want to

早晨不想出去跑步，但我强迫自己出门跑步；或者正在跑步兴致盎然时，明知该回去了，却还想再跑一英里。

go out for a run-in the morning, but I'm going to make myself go out for a run or I'm having a great time out on a run and I know I need to get back, but I kind of want to go another mile.

另一个经典例子就是儿童棉花糖测试。如果孩子能坚持最初三十秒不拿，就能得到两颗棉花糖——他们可以立即拿一颗，但若能等待三十秒，就能获得两颗。这就是'抑制'行为，因为他们的皮层在说：我确实更想要两颗而非一颗，但若不克制拿第一颗的冲动，就得不到两颗。所以他们必须抑制行动，而这必然源自认知过程。

I mean, another great example is that, you know, the marshmallow test for the little kids, you know, they can get two marshmallows if they hold off, just thirty seconds initially. They can have one right away, but if they can wait thirty seconds, they got two. So that's the no go because their cortex is saying, I would really like to have two more than having one, but they're not going to get the two unless they can not reach for the one. So they've got to hold off the action. And that has to result from a cognitive process.

因此大脑皮层在其中起着关键作用。为什么你...

So the cortex is involved in this in a major way. Why do you

我认为有些人在执行这些'去/不去'神经回路时更为困难，而另一些人则似乎具有很低的激活能量，可以这么说。他们接到任务就能直接投入其中，而对某些人来说，启动任务或完成这类事情则极具挑战性。

think that some people have a harder time running these go no go circuits and other people seem to have very low activation energy, we would say. Can just, you know, they have a task, they just lean into the task. Whereas some people getting into task completion or things of that sort is very challenging for them.

我认为这实际上只是另一个特例，属于一个普遍现象——大脑极其复杂，而我们拥有的这些大脑是基因和经验共同作用的结果。我的基因与你不同，我的经历也与你不同。因此，对我们来说容易或困难的事情未必一致。它们之所以如此，可能仅仅因为本就如此。关键在于，你被分发到一手特定的牌，拥有特定的基因，被赋予了一个大脑。

I mean, I think it's really just another, it's a special case of a very general phenomenon, which is brains are complicated and the brains we have are the result of genetics and experience. And my genes are different from your genes and my experiences are different from your experiences. So the things that are be easier or hard for us won't necessarily be aligned. They might just happen to be just because they are. But the point is that you're dealt a certain set of cards, you have certain set of genes, you are handed a brain.

你无法选择自己的大脑，它是被赋予的。但之后你可以用它做很多事情：学习新技能、改变行为方式、或表现出更多克制——这与我们正在讨论的内容颇为相关。

You don't choose your brain, it's handed to you. But then there's all this stuff you can do with it. You can learn to have new skills or to act differently or to show more restraint, which is kind of relevant to what we're talking about here.

没错，当然。我们讨论的所有结构都在并行运作，而且存在大量动态的交叉对话。那么让我们来谈谈大脑皮层。

Right, of course. Yeah, all the structures that we're discussing are working in parallel. Right. And there's a lot of changing crosstalk. So let's talk about the cortex.

正如行家所知，我们已经沿着所谓的'神经轴'向上探讨，现在到达了大脑皮层。这里是我们高级意识、自我认知、计划与行动的所在。但如你所言，皮层不仅限于此，它还包含参与其他功能的区域。

We've worked our way up the so called neuraxis as the aficionados will know. So we're in the cortex. This is the seat of our higher consciousness, self image, planning and action. But as you mentioned, the cortex isn't just about that. It's got other regions that are involved in other things.

那么或许我们应该继续围绕视觉系统，稍微讨论下视觉皮层。你曾告诉我一个关于视觉皮层的惊人故事，遗憾的是那是个有些悲伤的案例，关于一位视觉皮层中风患者。能否请你分享这个故事？我认为它能很好地阐释大脑皮层的诸多重要功能原理。

So maybe we should, staying with vision, let's talk a little bit about visual cortex. You told me a story, an amazing story about visual cortex, and it was somewhat of a sad story, unfortunately, about someone who had a stroke to visual cortex. Maybe if you would share that story, because I think it illustrates many important principles about what the cortex does.

当然。关键在于，我们这些有视力的人，视觉皮层中都存在着对视觉世界的表征。当有人因眼部（可能是视网膜）问题失明后会发生什么？大脑皮层中原本期待视觉系统输入的大片宝贵神经处理区域，突然失去了输入来源。你可以把这想象成休耕的土地，对吧？

Sure. So the point is that you all, those of us who see have representations of the visual world in our visual cortex. What happens to somebody when they become blind because of problems in the eye, the retina perhaps. You have a big chunk of the cortex, this really valuable real estate for neural processing that has come to expect input from the visual system and there isn't any anymore. So you might think about that as fallow land, right?

神经系统并未使用它。这原本会是件憾事，但事实证明它确实被利用了。你提到的案例是一位自幼失明的女性，她通过努力晋升至一家大型企业的高级行政秘书职位。她极其擅长盲文阅读，拥有一台盲文打字机，所有工作都借此完成。后来她突发中风，在工作时昏倒被送往医院。

It's unused by the nervous system. That would be a pity, but it turns out that it is in fact used. And the case that you're talking about is of a woman who was blind from very early in her life and who had risen through the ranks to a very high level executive secretarial position in a major corporation. And she was extremely good at braille reading and she had a braille typewriter and that's how everything was done. And apparently she had a stroke and was discovered at work, collapsed and they brought her to the hospital.

接诊的神经科医生在她苏醒后说：'我有好消息和坏消息。坏消息是你中风了。好消息是病灶位于你根本没用的大脑区域——你的视觉皮层，而我知道你先天失明，所以应该不会有问题。'但问题在于她丧失了盲文阅读能力。后续人类影像实验证实：先天失明者的大脑会将视觉皮层重组为触觉信息处理中心。

And apparently the neurologist who saw her when she finally came to said, I've got good news and bad news. Bad news is you've had a stroke. The good news is that it was in an area of your brain you're not even using, It's your visual cortex and I know you're blind from birth, so there shouldn't be any issue here. The problem was she lost her ability to read Braille. So what appears to have been the case and this has been confirmed in other ways by imaging experiments in humans, is that in people who are blind from very early in birth, the visual cortex gets repurposed as a center for processing tactile information.

特别是经过专业盲文训练后，这部分本该处理视觉信号的皮层区域，实际上被重新分配给了指尖触觉。这展现了惊人的神经可塑性。它表明视觉皮层本质上是多功能信息处理器——擅长处理空间信息，而指尖皮肤恰是另一种空间感知渠道。当缺乏常规输入时，大脑会智能地自我重组，将这块'神经地产'用于更有价值的用途，比如盲文阅读。

And especially if you train to be a good braille reader, you're actually reallocating somehow that real estate to your fingertips, a part of the cortex that should be listening to the eyes. So that's an extreme level of plasticity. But what it shows is the visual cortex is kind of a general purpose processing machine. It's good at spatial information and the skin of your fingers is just another spatial sense and deprived of any other input. The brain seems smart enough, if you want to put it that way, to rewire itself, to use that real estate for something useful, this case, reading braille.

令人震撼。虽带些悲剧色彩，但确实惊人。至少这个案例极具启发性。当然反向案例也存在，比如丧失视觉的人可能发展出更强的听觉或触觉功能。

Incredible. Somewhat tragic, but incredible. At least in that case Very informative. Very informative. And of course it can go the other way too, where people can gain function in particular modalities like improved hearing or tactile function in the absence of vision.

大卫，这次对话太精彩了。

Listen, David, this has been wonderful.

我也非常尽兴。

It's been a blast.

我们衷心感谢你抽空参与。听众现在应该都意识到，你是整个神经系统领域的知识宝库。今天我们只是浅尝辄止地探讨了多个领域，展现神经系统运作与组织的精妙架构。我最敬佩你的是——你不仅是位卓越的教育者（这些年来我教过无数学生），作为朋友，每当我想要探索神经系统的奥妙，思考那些未曾留意的新问题时，你总是我的第一咨询对象。所以请原谅我过去、现在和未来的电话骚扰，即便你换了号码，我也一定会找到你。

We really appreciate you taking the time to do this. As people probably realize by now, you're an incredible wealth of knowledge about the entire nervous system. Today, we just hit this top contour of a number of different areas to give a flavor of the different ways that the nervous system works and is organized and how that's put together, how these areas are talking to one another. What I love about you is that you're such an incredible educator and I've taught so many students over the years, but also for me personally as friends, but also anytime that I want to touch into the beauty of the nervous system and start thinking about new problems and ways that the nervous system is doing things that I hadn't thought about, I call you. So please forgive me for the calls past, present, and future, unless you change And your even if you do, I'll be calling.

A和E，这真是太棒了。这次交流非常愉快，和你们交谈总是充满乐趣，总能让我思维活跃。所以谢谢你们，非常感谢。

It's been such a blast, A and E. This has been a great session and it's always fun talking to you. It always gets my brain racing. So thank you. Thank you.