神经科学家解析：感知的边界与幻觉的起源

《卫报》。

The Guardian.

LSD不像酒精或巴比妥类药物那样是一种毒品。

LSD is not a drug like alcohol or a barbiturate.

LSD是一种含有数百部《大英百科全书》的化学物质。

LSD is a chemical which contains several 100 Encyclopedia Britannica.

所以当你与服用LSD的人交谈，或者你身边有人服用LSD时，他的意识正在穿越许多不同层次的语言——这些语言不是英语、法语或拉丁语，而是细胞、神经系统和感觉器官的化学语言，它们已有数百万年的历史。

So when you talk to someone who's taking LSD or if you have a sitting who's taking LSD, his consciousness is being spun through many, many different levels of language, which are not the language of English or French or Latin, but chemical languages of cell and nervous system and sense organ, which are many millions of years old.

大家好，欢迎来到‘一位神经科学家解释’节目。

Hello, and welcome to a neuroscientist explains.

我是丹尼尔·格拉泽，曾是一名神经科学家。

I'm Daniel Glaser, and I am a former neuroscientist.

我可能会着迷欣喜，也可能会惊恐万分。

I can be entranced and delighted, or I can be very frightened.

我还是伦敦新科学画廊的馆长，该机构隶属于伦敦国王学院。

I'm also director of the new Science Gallery London, which is part of King's College London.

在两年多的时间里，我还为《观察家杂志》撰写每周专栏，通过一位前神经科学家的视角探索文化领域和时事热点。

For a little over two years, I also wrote a weekly column for The Observer Magazine, wherein I explored the world of culture culture and topical events through the eyes of a former neuroscientist.

所以在本播客第二季中，我们将重温其中一些专栏文章，并探讨其中涉及的神经科学。

So in season two of this podcast, we're revisiting some of those columns and exploring the neuroscience within.

本周我们将探讨正常感知在哪里结束，异常幻觉从哪里开始。

And this week, we'll be looking at where normal perception ends and abnormal hallucination begins.

我认为除非我们具备产生幻觉的能力，否则根本无法感知或看见任何事物。

I think it would be impossible for us to perceive or to see anything unless we also had the ability to hallucinate.

这涉及大脑中相同的运作机制。

It's the same mechanisms involved in the brain.

大脑会对世界存在的事物形成各种假设，而不同形式的感知正是这些不同假设的体现。

The brain has hypotheses about what's out there in the world, and perceptions, different kinds of perceptions are these different hypotheses.

这种情况从未发生过。

It never happens.

但我记得读完那篇文章后大约半年时间里

But I remember for about six months after I read that.

是的。

Yeah.

然后

And then

它发生在你身上了。

it happens to you.

现在它要发生了

Now it's gonna happen

每次我我有个

Every to time I I have an

正如你们现在所知，每期节目都始于一段对话，感谢你们带来的萦绕心头的感受。

As you all know by now, each episode begins with a single conversation And and thank you for the haunting.

其实。

Actually.

在我明天为朋友做周六早晨的法式吐司时，请记住这一点，还有制作人马克斯。

Between me Bear it in mind tomorrow when I make my friend my Saturday morning French toast and producer Max.

你好，丹。

Hello, Dan.

嗨，马克斯。

Hi, Max.

我是说，我们有一阵子没问过对方近况了。

I mean, we haven't really asked each other how we are for a while.

你最近怎么样？

How are you doing?

一切都好。

Things good.

一切都好。

Things good.

我想，你知道的，快到假期了。

I think, you know, approaching the holiday season.

是啊。

We are.

我们快到了。

We are approaching.

今天感觉像是夏天，但我对这些事情总是容易想太多。

It feels today I mean, I think it's summery, but I get carried away with these things.

感觉非常春天。

Feels very spring.

不过，就像你说的，快到夏季了，包括音乐节季。

But, like you say, approaching the summer seasons, includes music festival season.

音乐节。

Music festivals.

马克斯正在做一个类似狂欢者的手势。

And Max is doing a kind of raver's gesture.

他说这话时双臂张开。

He's got his arms outstretched as he says that.

确实如此，马克斯。

Indeed, Max.

这周的专栏，正如你巧妙地引出季节话题那样，马克斯，主题正是关于节庆的。

And the column, you know, that we're looking at this week as as you've, you know, beautifully, if I may say, Max, teed up your seasonal remark, is about festivals.

有趣的是，马克斯，当我撰写时，专栏始终关注着世界动态。

And it's interesting, Max, when I wrote it, you know, like the column was always about what was going on in the world.

在英国尤为明显，格拉斯顿伯里音乐节已成为人们文化生活的重要部分。

And so, in The UK certainly, know, Glastonbury, that music festival is is quite a dominant bit of people's cultural lives.

这个传统我一直都有关注。

And I've always, you know, had it.

我总是能感知它的临近，但事实证明，在格拉斯顿伯里期间让人回复邮件变得越来越困难。

I've always known when it's coming, and it's also increasingly hard to get people to answer emails, it turns out, at Glastonbury.

出乎意料的是，那里人潮汹涌。

Surprisingly, there's lot of people there.

不过我并不属于那群人。

But I do not count myself among them.

对吧？

Right?

所以我从未参加过音乐节，我也不太清楚为什么，你知道吗，就像这些事情，我不确定对你来说是否也是如此，麦克斯，但那些你不做的事情，你不做只是因为你不做，就像我不参加音乐节一样。

So I've never been to a music festival, and I don't know quite why, you know, like these things, I don't know if it's true for you, Max, but the things which you don't do, and you don't do them because you don't do them, like I don't do music festival.

但你从未真正问过自己为什么会这样。

But you never really ask yourself why that is.

这篇文章也谈到了人们在音乐节上做的事情，以及其他一些事情。

And the piece was also about things that people do at music festivals, among other things.

其中之一就是致幻药物。

And one of them is hallucinogenic drugs.

麦克斯说，好吧，你知道，我很坦诚，但我从未尝试过致幻药物，不过我知道有人会服用，而且通常在音乐节上使用。

And Max says, well, you know, I'm very confessional, but I've never done a hallucinogenic drug, but I'm aware that people do them, and that often they're done at festivals.

所以这篇文章有点关于两件我不做的事情——服用致幻药物和参加音乐节。

And so the column is a little bit about two things I don't do hallucinogenic drugs and music festivals.

嘿，这或许就是专栏写作的魅力所在，你可以探索日常生活中无法触及的世界。

Hey, that's the appeal perhaps of writing in columns, you get to explore worlds which you cannot in your everyday life'.

但你探索过——我是说你两者都没经历过，所以你没有那些体验，但作为前神经科学家，你研究过致幻药物的神经科学。

But you explored I mean you haven't been to either so you don't have an experience of those things but obviously as a former neuroscientist you explored the neuroscience of hallucinogenics.

你写了些什么内容？

What did you write about?

这算是一种假设，但确实也包含了一些确定的真相。有趣的是，与我们在马克斯节目里讨论的许多话题不同，这个话题恰好是我真正有所了解的领域。

So it's kind of a hypothesis, but it's also yeah, there's definite truth in this and it is an area, funnily enough, unlike a lot of what we do in this thing Max, where I actually do know something about it.

我认为大多数人对于感知运作方式的模型是这样的：比如说视觉信息，是从外界通过眼睛传入的。

So I guess what most people's model of the way that perception works is that, you know, information flows into your eye, let's say if it's visual stuff, from the world.

光子从物体上反射进入眼睛，然后通过某种层级结构进行处理。

So photons bounce off things, flow into your eye, and then get kind of processed by some kind of hierarchy.

所以你把点连成线，把线连成形状，把形状组成物体，再把物体放入场景，这就是我们看东西的方式。

So So you pull out the dots, you join the dots up into lines, and you join the lines up into shapes, and you join the shapes up into objects, and you put the objects into scenes, and that's how you see.

这就是我们所说的自下而上。

That's what we call bottom up.

我想我们在之前的播客中也讨论过一些相关内容。

And I think we've talked about bits of this in the previous podcast as well.

但实际上，如果你观察大脑的解剖结构，会发现有同样多的连接向下传递到视网膜——实际上不是视神经（视神经是单向的）——而是向这些较低层级传递的连接与向上传递的一样多。

But actually, if you look at the anatomy of the brain, there's as many connections going out towards the retina not in fact the retinal nerve, the optic nerve is one way but towards the retina, towards these lower levels, there's as many connections going down as going up.

这意味着从你的高级思维过程中下行的信息量，与外界流入的信息量是相当的。

What that means is that there's as much coming down from what you think about in your higher level thought processes as there is information flowing in.

我在专栏中思考的是，当我们产生幻觉——即看到不存在的事物时，大多数人会认为这很怪异，仿佛视觉系统在以某种非自然的方式运作。

And I guess what I was wondering about in the column is that when we hallucinate, which is sort of seeing things that aren't there, most people would imagine, I think, that that's kind of weird, as if the visual system is behaving in a kind of unnatural way.

但事实上，我认为幻觉是完全自然的。

But actually, my thought is that hallucination is perfectly natural.

实际上，我们所看到的世界本身就是一种幻觉。

In fact, we hallucinate the world that we see.

只是我们不断地用视网膜接收的信息来验证这些幻觉。

It's just that we're checking our hallucinations against our retinas all the time.

我有几个事情要坦白。

So I've got a couple of confessions to make.

不，麦克斯。

No, Max.

好吧。

Okay.

你没去过音乐节也没尝试过致幻药物吧。

You haven't been You to haven't music been to a music festival or done hallucinogenic drugs.

我两样都试过。

I've done both.

同时进行的吗？

At the same time?

是的。

Yeah.

大概吧。

Probably.

我想那大概是我唯一尝试过这些东西的地方。

I think that's yeah probably the only place I've ever done them.

但我可以放心地说这两件事都已成为过去。

But both of them are behind me I can say safely.

不过你说的很有意思，除此之外，我还...我不会具体说是什么。

But it's interesting what you say because I suppose on top of that, I also I'm not gonna say what it is.

我还被诊断出患有一种病症，我想其核心问题在于我对周围世界的感知存在障碍，这会让事物有时显得极其阴暗，有时又异常明亮。

I've also been diagnosed with a condition which means that I suppose that the heart of it is that I have problems with perceiving the world around me and can make things feel very dark or sometimes very light.

根据我头脑所处的状态不同，我喜欢认为——我对世界的感知很大程度上受到那种对世界本质的预设观念所驱动，不知道这样说是否合理。

And depending on what kind of state my my head is in, I like to think, the way that I perceive the world is very much driven by that sort of preconception of of how the world is, if that makes sense.

确实如此。

It does.

当我第一次服用致幻剂时——我不是在提倡大家去尝试——但对我来说这具有极强治疗意义。因为经历完整个过程后，我达到了某种与自己病症和解的状态，这比服药前要好得多。毕竟想想看：我仅仅是往嘴里放了某种化学物质，随后八到九小时里，我对世界的感知方式就彻底改变了。

And when I took hallucinogenics for the first time, for me, and I'm not I'm not saying people should go out and take them but for me it was very therapeutic because what happened was after, you know, the whole thing had finished, there was a moment that I kind of came to terms with the condition that I have better than I had before I took the hallucinogenic substance because, you know, the fact that I could put something in my mouth, some sort of chemical, and then for the next sort of, you know, eight to nine hours, I perceived the world in a completely different way.

这让我意识到，我的日常感知有多少实际上是由你所说的那些东西驱动的。

What it made me realize was how much of my everyday perception was actually driven by the things you're saying.

更确切地说，是由我自上而下的、对周围世界和你如何运作的感知方式驱动的

By my sort of top down, rather, is top down sort of perceptions of how I thought the world was around me and you

要知道在幻觉和听众的语境中提到的兔子耳朵

know rabbit ears in the context of hallucinations and listeners.

我在马克斯头上看不到任何兔子耳朵，但你继续说吧

I cannot see any rabbit ears on on Max's head but keep going.

兔子耳朵是引号里的内容，各位。

Rabbit ears was quotation marks for anyone.

但你知道，这并没有解决任何问题，也没有修复什么。

But and it hasn't, you know, it hasn't solved anything, hasn't fixed anything.

我知道他们正在研究这类物质对精神健康障碍的潜在作用。

And I know that they are looking at the the power of these kind of substances for mental health disorders.

但它确实让我接受了一个事实，正如我所说，我的日常感知在多大程度上被我内心的状态所改变。

But it what it did was allow me to come to terms with the fact, yeah, like I said, that that how much of my everyday perception is sort of altered by my sort of the state of my inner mind if you like.

所以我想，这大概就是我们本周想要探讨的内容。

And so that I suppose is kind of what we want to explore this week.

完全同意。

Absolutely.

马克斯，有必要声明一下，我们并不提倡使用这些东西，我们相信听众们，他们中许多都是负责任的成年人，会自己做决定，咨询医生，我们并非在倡导其治疗用途，请查阅研究并与医疗专家沟通。

Max, it's probably worth just saying, for the record, that we don't advocate the use of this stuff, that we believe our listeners, many of them responsible adults, make your own decisions, talk to your doctor and we're not advocating it for therapeutic use, look at the research and talk to your medical practitioner and expert.

但对我来说这周有趣的是，要验证我的直觉是否正确：幻觉是否其实很像视觉，只是少了现实检验；或者说幻觉是否是一种完全不同的感知方式，你的大脑运作方式与正常视觉时完全不同。

But the interesting thing for me this week, Max, is to look at the question of whether my hunch is right that hallucinating is actually quite a lot like seeing, but with less reality checking, or whether hallucinating is like a totally different kind of perception of the world that your brain is acting in a completely different way than when you're seeing things normally.

为了找出答案，制片人马克斯和我进行了一次短途旅行。

And to find out, producer Max and I took a little trip.

不。

No.

不是那种致幻性质的。

Not the hallucinogenic kind.

是火车代步的那种。

The train mediated kind.

是啊。

Yeah.

不。

No.

那倒是真的。

That's true.

不过我觉得，嗯。

But I think as yeah.

我想这一定是

This must be I think it's

不是个打发时间的好地方。

not a bad place to waste some time.

早上好。

Good morning.

你好。

Hello.

你怎么样？

How are you doing?

我是丹尼尔。

I'm Daniel.

正是在校园里，我们找到了我们正在寻找的神经科学家。

And it was on campus that we found the neuroscientist we were looking for.

我是阿尼尔·塞斯，萨塞克斯大学认知与计算神经科学教授。

I'm Anil Seth, and I'm professor of cognitive and computational neuroscience at the University of Sussex.

非常感谢你们邀请我们过来。

Well, thanks very much for having us down.

正如我们路上所说，Anil在幻觉与意识领域也是顶尖专家，他在精彩的TED演讲中对这些话题有非常精辟的论述。

And as we were saying on the way Anil is also a leading expert in hallucinations and consciousness, something he speaks eloquently about in his brilliant TED talk.

快去搜索看看。

Go search for it.

在交谈过程中，我开始思考或许... 开启我们的对话时，我直接询问Anil当我们谈论幻觉时究竟指的是什么，以及这与真实世界中看到事物有何不同。

Talking, I began to think maybe Starting off our conversation, I asked Anil exactly what we mean when we talk about hallucination, and how this differs to actually seeing things in the actual world.

我认为'幻觉'这个词经常被有些误导性地使用，仿佛正常感知和幻觉之间存在着绝对的界限。

Think the term hallucination is often used a little bit misleadingly as if there's just this categorical difference between normal perception on the one side and then the other side hallucination.

所谓正常感知，就像你说的，是对外部现实在头脑中的某种重现——这就是我们感知周围世界时的运作方式。

So normal perception being as you say, this sort of recapitulation of some actually existing external reality inside the head and that's what we do when we perceive the ex of the world around us.

而幻觉则是看到不存在的东西，比如可能在脑海中听到声音，或是看到别人看不见的人影。

And hallucination being seeing things that aren't there, where you might actually just perceive hear a voice in your head or or see something out there, a person that other people don't see.

我更倾向于认为，关于幻觉的故事实际上讲述的是感知与幻觉之间的连续性——某种程度上说，如果我们不具备产生幻觉的能力，就根本不可能真正地看见任何事物。

And I rather think that the story about hallucinations is is a story of a a continuity or a graded process between perception and hallucination to the extent that I think it would be impossible for us to perceive or to see anything unless we also had the ability to hallucinate.

这是大脑中相同的机制在起作用。

It's the same mechanisms involved in the brain.

所以你是说，如果幻觉没有在这个系统中发生，你就无法进行视觉感知？

So you're saying you couldn't do seeing if hallucination didn't happen in that system as well?

我认为它们之间的联系甚至比那更紧密。

I think it's even more closely linked than that.

我认为视觉，或者我更愿意称之为感知。

I think seeing, or I prefer to say perceiving.

让我稍微退一步讲，'看见'这个概念强调了眼睛和传入的感觉数据。

Let me just step back a tiny bit to the idea of seeing emphasizes the eyes and the sensory data coming in.

当我们说'看见'某物时，通常意味着我们正在接收感觉数据。

When we say the word, to see something, it can often mean that we're registering sensory data.

我认为'感知'更接近于我们所经历的体验，是对那些感觉数据的诠释。

Perceiving is, I think, more closely related to what we experience and is the interpretation of that sensory data.

正是在对感觉数据的诠释中，我们发现了幻觉与正常感知之间的共同机制。

And it's in the interpretation of sensory data that we find the common mechanisms between hallucination and normal perception.

非常非常简单地想一想。

Think of it very, very simply.

幻觉是指你的解读超出了感官数据，且与周围其他人的方式不同。

Hallucination is when your interpretation exceeds the sensory data in a way that's different from other people around you.

感知则是你的解读受到感官数据的约束，且与周围人共享相同方式。

Perceiving is when your interpretation is reined in by the sensory data in a way that is shared with the people around you.

所以最终你会说你看到或感知到相同的事物。

So you end up saying that you see or saying that you perceive the same things.

但就在极端情况下，我想可以用一种略带卡通化的方式来说。

But just on the extreme end, and I suppose there's a there's a slightly cartoonish way of saying this.

如果你听到有人说——可能是懂脑科学的人也可能不懂——说视觉就像把外部世界的现实传输进你的大脑。

If you hear somebody saying, and be that somebody who knows about the brain or someone who doesn't, you know, that seeing is like transmitting reality from out in the world into your head.

你会不会私下里——也许在研讨室里和朋友在一起时——'啊！'，你知道，'那家伙真以为现实就在外面，然后把它塞进脑袋里'。

Do you secretly, and maybe when you're among friends in the seminar room, 'ah!', you know, 'that guy actually thinks that there's this reality out there, and you put it into your head.

你是否觉得这种极端纯粹的视觉观念——仿佛存在一个现实而你只是看见它——很荒谬？

Do find the idea, as it were, at that extreme end of just seeing, of just seeing, as if there was a reality and you you see it?

这完全疯了吗？

Is that completely crazy?

在某种程度上，这正是我们被设计来体验世界的方式。

In a way, it's it's how we're designed to experience the world.

我们天生就有这种朴素现实主义。

We have this naive realism that we're built that way.

当我早晨起床环顾房间时，我感知到房间就在那里，里面有各种物体、桌椅，它们有颜色，声音从其他房间传来，来自那些房间里的人。

When I get up in the morning and look around my room, I perceive the room as being out there and have and and that there are objects, tables and chairs that have colors and voices that emerge from other rooms, emerge from other people in those other rooms.

所以从某种意义上说，我们无法摆脱这种体验世界的方式，这很正常。

So in one sense, we can't get away from this way of experiencing the world, and that's normal.

如果我们认为自己的感知并非真实存在，那将非常成问题。

It would be very problematic for us to experience our perceptions as not really existing.

正如你所知，在某些脑损伤和精神障碍情况下确实会出现这种情况。

Now this can happen in certain kinds of brain injury and psychiatric disorder, as you know.

但同时，我确信我们所感知的并非外部现实的反映。

But at the same time, it's certainly true to me that what we perceive is not reflection of an external reality.

一个有用的思考方式是从颜色入手。

One way to think about this that's useful comes from thinking about colors.

因为大多数人都熟悉颜色并不具有客观外在存在这一概念。

Because most people are familiar with the idea that colors don't have an objective external existence.

我的意思是，这并不一定来自心理学或神经科学。

I mean, this is not something that necessarily comes from psychology or neuroscience.

这源于物理学和牛顿的研究。

This comes from from physics and from Newton.

光只是具有不同波长的能量波。

Light just has wavelengths of energy with different wavelengths.

而我们的眼睛拥有能对电磁频谱不同频率做出反应的感受器。

And our eyes have receptors that respond to different frequencies of the electromagnetic spectrum.

颜色是通过这些感受器的活动组合产生的，反映了不同波长的组合。

And colors are generated through combinations of activities of these receptors, which reflect different combinations of wavelengths.

所以世界上并不存在所谓的'红色'。

So there's no red out there in the world.

红色是对特定光波长的解读。

Red is an interpretation of particular wavelengths of of light.

因此，我们的大脑构建了红色的体验——如果你是色盲，就看不到某些颜色。其他物种眼中也有不同的受体，所以它们的感知色彩空间会比我们更广阔。

And so our brain constructs the experience of red if you're color blind, you don't see certain colors, Other species have other receptors in their eyes as well, and so we'll have a larger perceptual color space than we do.

所以即便我主观认为颜色存在于外界，我们无需神经科学知识也明白：颜色未必客观存在于世界，而是在我们的感知中被构建出来的。

So already, even though I experience colors as existing out there, we know even without neuroscience that colors don't necessarily exist objectively in the world, and they're constructed somehow in our perception.

关于感知与幻觉的观点，实质上是将这个理念泛化——即大脑以相同方式或类似原则，构建出我们所感知和经历的一切事物的知觉内容。

And the idea about perception and hallucination is really to generalize that idea, and to say that in the same way or according to a similar principle, the brain constructs perceptual content of everything that we perceive, everything that we experience.

正如安内尔所说，外部真实世界存在的事物与我们头脑内部的感知方式，并不总是一致的。

So, as Annel says, what exists out there in the real world, and how we perceive it in here, inside our heads, doesn't always line up.

这一点对感知和幻觉都同样适用。

And that's the same for both perception and hallucination.

短暂休息后，我们将尝试解析这背后的神经科学原理，并厘清二者间的区别。

After this short break, we'll attempt to unpick the neuroscience behind this and unravel the difference between the two.

自上而下的信号——如果你愿意这么理解——这些由内向外传递、携带着关于感官数据成因预测的信号，其本质是相同的。

The top down signals, if you like, the signals coming from inside out that are carrying predictions about what is causing sensory data would be the same.

可能不同的是，在这些人的大脑中，此时对某些方面存在过度强调

What probably is different is that there is in the brains of these people at these times an overemphasis on the

预测

predictions.

我们马上回来

We'll be right back.

欢迎收听《起点》，这是《卫报》全新推出的每周播客节目

Welcome to the start, a brand new weekly podcast from The Guardian.

如果没有那些与现实互动的经历，我就不会成为今天的我

Without those kind of engaging with reality, I will not become I will be today.

每一个

Each

每期节目都将讲述一位当代伟大艺术家的艺术起源故事

episode reveals a story of artistic beginnings as told by some of the great artists of our time.

对我来说，《Scandalicious》很大程度上也是关于我寻找自我道路的过程

For me, Scandalicious, so much of that was also about me finding my way.

他们聚焦于一件作品，分享这些早期的创作时刻如何塑造了他们，对其后续作品产生了怎样的影响，以及如今回首时这件作品对他们的意义。

Focusing on one piece, they share how these early moments of creativity shaped them, the influence it had on their subsequent work, and what the piece now means to them in retrospect.

我在任何房间、任何艺术展览中见过最多的作品，就是在巴恩斯先生的两个房间里。

The most I've ever seen in any room, know, looking at any kind of art was in mister Barnes' two rooms.

欲了解更多详情，请访问theguardian.com/podcasts或在您喜爱的播客应用中搜索'The Start'。

To find out more, head over to theguardian.com/podcasts or search The Start on your favorite podcast app.

欢迎回到《神经科学家解读》节目。

Welcome back to A Neuroscientist Explains.

我是丹尼尔·格拉泽。

I'm Daniel Glaser.

在休息之前，我们谈到了幻觉，特别是它们是否真的与传统的日常感知有很大不同。

Before the break, we were talking hallucinations, and specifically, whether they're really all that different to good old fashioned everyday perception.

这促使制片人马克斯和我前往苏塞克斯，在那里我们遇到了认知神经科学家阿尼尔·塞斯。

It's something that led producer Max and me to take a trip down to Sussex, where we found cognitive neuroscientist, Anil Seth.

阿尼尔提到的一个观点是，他认为如果无法产生幻觉，就不可能感知任何事物。

Now, something Anil said was that he didn't think it would be possible to perceive anything without being able to also hallucinate.

不一定非要区分，比如说，我不确定某些界限。为了深入探讨，我给Annel设计了一个小小的思维实验。

Not necessarily distinguishing between, let's say, I don't know, some breaks So to dig a little further, I gave Annel a little thought experiment.

想象你正坐在沙发上，望向窗外，看到一个热气球飘过。

Imagine that you're sitting here on the sofa, and you look out the window, and you see a hot air balloon floating past.

再想象存在两种可能性。

And imagine that there were two possibilities.

对吧？

Right?

要么从深层的物理意义上确实存在一个热气球，要么根本不存在。

Either in some deep physical sense there is a hot air balloon, or there isn't.

在这两种情况下，你的大脑状态有何不同？

How different is the state of your brain in those two cases?

这个假设性的例子很有趣，我之前从未遇到过。

This is an interesting hypothetical example I haven't encountered before.

我只是看着窗外蓝色的天空，所以想到了这个。

I'm just looking at the blue sky out the window, and that's why it came to me.

我视野范围内没有热气球。

There is no balloon as far as I can see.

你知道，感知到的现实可能有所不同。

You know, access reality may be different.

确实如此。

That's true.

我也没看到。

I can't see one either.

也许你

Maybe you

能看到。

can.

我知道

I know

这一点。

that.

我们待会儿再找你，伙计。

We'll come back to you later, mate.

我认为，这两种状态下大脑的区别，归根结底在于接收到的感觉数据存在差异。

The difference between the two conditions in terms of your brain, I think, would come down to a difference in the the sensory data that's coming in.

所以如果外界确实存在某物，就会导致特定类型的能量进入你的眼睛，从而改变那些逐渐深入大脑的感觉数据。

So if there actually is something out there, that would result in some particular kind of energy hitting your eyes, would change the sensory data that percolates deeper and deeper into your brain.

但如果你不论是否有热气球都感知到相同的事物，那在我看来，这意味着大脑对所接收感觉数据做出的推断是相同的。

If you are nonetheless perceiving the same thing regardless of whether there was a hot air balloon or not, that would mean to me that the inference that your brain is making about whatever sensory data it's getting is the same.

这有点复杂。

Now, that's a bit complicated.

我的意思是，自上而下的信号——如果你愿意这么称呼的话——那些由内向外传递、携带着关于感觉数据成因预测的信号会是相同的。

What I mean by that is that the top down signals, if you like, the signals coming from inside out that are carrying predictions about what is causing sensory data would be the same.

所以大脑中会有所有这些预测，基本上以神经元特有的语言表示：对传入感觉数据的最佳解释是外面有个热气球。

So you'd have all these predictions in the brain, basically, in whatever language that neurons speak, saying the best explanation of the sensory data that's coming in is that there's a hot air balloon out there.

这基于一个观点：我们所感知到的是大脑对感觉数据成因所做预测的内容。

And this is based on the idea that what we perceive is the content of the brain's predictions about what's causing the sensory data.

现在我有个非常蠢的问题。

So I've got a really dumb question now.

所以...我理解你的意思是，如果我没记错的话，实际上从大脑传递到视网膜的信息并不多。

So so so I hear you as saying roughly that if I was there's not much information that actually hits the retina from your brain as far as I remember.

这基本上是个单向过程。

It's mostly a one way street.

但一旦进入大脑内部，就完全是双向的了。

Then once you hit inside the head, it's all pretty two way.

所以如果我要在这两种情况下读取你的视网膜信号，我大概能分辨出有没有那个该死的热气球。

So if I were to read out your retina in the two cases, I'd probably be able to tell the difference between there being a bloody great balloon and there not being a bloody great balloon.

但现在关于大脑部分，有多少脑区是负责你正在感知的内容的？

But for the brain stuff now, how much of the brain is concerned with what it is you're perceiving?

又有多少是负责与视网膜相关的部分，也就是处理输入信号的部分？

And how much of it is concerned with, as it were, the stuff that's tied to your retina, the stuff that's about the signals coming in?

感知是否主要来自内部生成？

Is it mostly perception that's generated from within?

是五五开吗？

Is it fiftyfifty?

这是个蠢问题，但你懂我意思。

It's a dumb question, but you know what I mean.

这是个非常有趣的问题，但我不确定能用‘感知占多少百分比’这样的方式来回答，这是一个本质上两者都参与的过程。

It's it's a very interesting question, but I'm not sure it can be answered in those in those terms of this percentage is to do with perception, it's a process that intrinsically involves both.

神经科学中普遍的观点是，大脑持续在检验它对外部世界的预测。

And the idea is or the idea that I is common in neuroscience and thinking about this, is that the brain continually is testing its predictions about what's out there.

理查德·格雷戈里曾著名地将感知描述为类似科学家检验假设的过程。

Richard Gregory famously described perception as a process of hypothesis testing much like scientists would test their hypotheses.

大脑对世界存在各种假设，而不同感知就是这些不同的假设。

The brain has hypotheses about what's out there in the world, and perceptions, different kinds of perceptions are these different hypotheses.

它们通过感官数据的检验。

They're tested against the court of sensory data.

感官数据输入后，会证实、否定或修正大脑持有的假设。

Sensory data comes in and either confirms or disconfirms or refines the hypothesis that the brain has.

这解释了许多关于神经解剖学和神经生理学原本令人困惑的现象。

This explains quite a lot of otherwise puzzling facts about neuroanatomy and neurophysiology.

我认为其中最显著的事实是，确实不仅仅存在大量连接，以你可能认为的反方向从大脑内部返回眼睛和耳朵。

I think the most prominent of these facts is that indeed it's not just that there are a lot of connections going in what you might think the reverse direction back out towards the eyes and the ears from the inside of the brain.

实际上，从大脑内部发出的连接比从感觉器官传入的连接要多得多。

There are actually many more of them than going the other day than come from the sensory organs in.

这是一种非常奇怪的逆转。

And it's a very strange inversion.

这种想法其实相当反直觉。

It's actually quite counterintuitive to think of this.

我们如此执着于这个观念，因为它看起来直观。

We're so wedded to the idea because it seems intuitive.

认为感知是关于外部信息进入大脑的过程。

That perception is about stuff coming into the brain from the outside.

随着信息深入大脑，可能会以更复杂的方式被处理。

And as it gets deeper into the brain, it gets maybe processed in more complicated ways.

但基本上，我们在某种程度上所感知到的，是由这些从外向内传递的信号承载的。

But basically, what we perceive is carried in some sense by these signals coming from the outside in.

而另一种我认为更正确（当然暂时如此）的观点是，我们所感知的、承载我们知觉的，是反向传递的信号，这些信号就是解释。

And the alternative, and I think more correct idea, provisionally correct, of course, is that what we perceive, what carries our perceptions are the signals that go the other way, and these are the interpretations.

但它们会持续与传入的感觉信号相互作用。

And but they're continually interacting with the sensory signals that come in.

感觉信号的作用只是精炼、反驳或否定这些假设。

Sensory signals just act to refine and disprove or disconfirm these hypotheses.

根据安内尔的观点，当我们感知外部世界时，进入大脑的不仅是冰冷生硬的感觉信息，实际上是我们对世界的预测与感官数据提供的证据之间的一场精妙舞蹈，这些证据要么支持预测，要么将其推翻。

So according to Annel, when we perceive the outside world, it's not just cold, hard sensory information coming in, but in fact a delicate dance between the predictions we make about the world and the evidence from sensory data that either supports or disproves them.

这可能转化为我们被淹没的体验

That could translate into the experience that we're being overwhelmed

但这种精妙的舞蹈在不同人之间是否存在差异？

But is this delicate dance different for different people?

将我们的注意力引导到这一点上

To direct our attention to this

这是制片人马克斯想知道的。

That's something producer Max wanted to know.

因为我猜个体之间会有巨大的差异。

Because I'm guessing there's gonna be huge variability within individuals.

有没有什么方法或测试能测量每个人在这个光谱上的位置，比如Trypometer？

Is there any way is there any test where you can measure that within each individual where they kind of sit on this spectrum between Trypometer.

是的。

Yeah.

Trypometer。

Trypometer.

试图在广泛人群中描述这种平衡是这一研究领域尚未解决的挑战之一。

Trying to characterize this balance in wide variety of people is one of the outstanding challenges in this area of research.

一种方法是设计相对简单但相当枯燥的实验，比如让人们听一个音调中非常细微的变化，这个变化有时存在有时不存在。

One way you can do this is by coming up with very relatively simple and quite boring to do experiments where people, for instance, just listen for a variation, a very subtle variation in the tone, which is sometimes there and and sometimes not there.

在这些情况下，人们有时会犯错，以为自己听到了声音但实际上并没有。

So in these cases, people will sometimes make errors where they think they heard a sound and there wasn't a sound.

现在这似乎有点奇怪，称之为幻觉。

Now this is it seems a little bit strange to call this a hallucination.

他们实际上只是产生了假阳性反应。

They're just making a a false positive really.

但你可以将其视为最小形式的感知幻觉，特别是如果他们表示确信自己听到了声音，而不仅仅是在猜测。

But you can think of it as the minimal form of a perceptual hallucination, especially if they say they were confident that they heard the sound rather than that they were just guessing.

通过这些非常简单且精简的范式，你可以开始量化不同人的行为特征，以及他们报告不存在声音的倾向性。

So with these very, very straightforward and reduced paradigms, you can begin to quantify things about how different people behave, their their propensity to report sounds that aren't there.

然后你就可以开始研究大脑中发生了什么。

And then you can start to look at what's going on in the brain.

耶鲁大学的菲利普·科莱特团队最近做了一项精彩的研究，他们采用了类似的范式，并选取了四组不同的人群。

There was a beautiful recent study by a group from Yale, Philip Collett, who used a paradigm like this, and they took four different groups of people.

他们有一组正常的对照组受试者，这些受试者通常不会报告幻觉。

They they had normal control subjects who didn't generally report hallucinations.

幻觉。

Hallucinations.

他们研究了患有精神分裂症并报告有幻觉及其他多种临床困扰症状的患者。

They had people with schizophrenia who reported hallucinations and also a variety of other clinically bothering symptoms.

他们还纳入了那些报告听到声音但并非精神分裂症患者的人群，这些人现在被称为'声音听者'。

Then they also had people who were reported hearing voices but without being schizophrenic, and these were people who now turned voice hearers.

这些人会经历听觉幻觉，但这些幻觉对他们来说并不构成问题。

So they would experience auditory hallucinations, but they weren't problematic for them.

然后是这个研究矩阵的最后一个群体，我正在思考那具体是指什么。

And then there's the final segment of that square, which I'm trying to figure what that that is now.

没错，当然。

That's right, of course.

没有出现幻觉的精神分裂症患者。

People with schizophrenia who didn't have hallucinations.

通过比较所有这些不同群体，菲尔·科莱特得以识别出参与这种最小形式幻觉的大脑区域。

And by comparing all these different groups, Phil Kollett was able to identify parts of the the brain that were involved in this minimal form of hallucination.

我确实认为，如果我们观察整个人群，不同人在这种平衡上的表现会存在相当大的差异。

And I do indeed think that if we if we look just across the population as a whole, there will be quite a lot of variety in how different people navigate this balance.

这是从这项工作中得出的一个非常有趣的启示。

And this is one of the very interesting lessons that follows from this work.

这不仅仅是区分一群拥有非常不同感知方式的人，他们确实会产生与我们其他人截然不同的幻觉。

It's not just about distinguishing a group of people who have very, very different sorts of perceptions, who really hallucinate things that are very different from the rest of us.

而是我们每个人看世界的方式都略有不同，我们可能意识不到这些感知上的细微差异，因为它们并不明显。

But that we all see the world slightly differently, and we may not recognize these subtle differences in how we perceive the world because they're just not apparent.

如果我说我看到窗外有棵树或热气球，你也看到了，通常这就足以让我们认为我们看到的是完全相同的东西。

If I say I see a tree or a hot air balloon out the window and you see it, then that's usually enough for us to assume that we're seeing exactly the same thing.

但无论如何，我们看事情的角度可能本就略有不同。

But we're probably seeing things slightly differently anyway.

这一点我们通过心理学的另一项研究也得以证实，它展示了不同语言如何改变人们的感知。

And we know this from another body of work in psychology which shows that how different languages can change your perception.

如果你对各类颜色或味道拥有更丰富的词汇描述，这会深化你对不同感知体验的区分能力。

If you have different a richer vocabulary for different kinds of colors or different kinds of tastes, that drills down into different sorts of perceptual experiences.

我认为这是一个非常重要的普遍启示——我们需要在更深层次上认识到：面对相同的外部情境时，人类不仅会产生不同的认知，甚至会产生截然不同的感官体验。

And I think this is is a very important general lesson just to recognize at a deeper level the potential for us to when facing the same external situation to not just believe different things about it, but to literally perceive it differently.

人们认为神经科学就是研究大脑运作机制的科学。

People think of neuroscience as someone who studies sort of the mechanisms by which the brain functions.

我对神经科学采取更广义的理解，因为我认为尤其是当你思考感知时，一切始于感知——从你穿的衣服、你爱上的人，到你看到的颜色。

I take a much more general approach to neuroscience because I think especially when you think about perception, everything begins with perception to the clothes you wear, the people you fall in love with, as well as the colors that you see.

因此，理解神经科学感知不仅是为了理解大脑如何工作，更是为了理解何以为人。

So to understand the neuroscience perception is not only to understand how the brain works, it's to actually understand what it is to be human.

在某种程度上，这确实存在社会因素，比如我们是否对外界事物达成共识，而且确实有很多情况下，两个人观察同一场景会对所见之物产生分歧。

In a way, there's a social element to it, in in part, you know, so whether we agree on what's out there or not, and, you know, and and there are lots of situations where two people looking at the same scene will disagree on what's out there.

可能是物体距离太远、被遮挡、发生得太快，或是发生在过去的事情。

Something is far away, or it's obscured, or it happened really quickly, or it's happened in the past.

也就是说，当你某种程度上'虚构'了自己所见，实际上与所有人的认知都不同时——这种情况其实时刻都在发生。

So, things where you've sort of invented what you've seen, in other words, really disagree with everybody else out there and you can check it, that happens kind of all the time.

但有些特殊状态中，你感知到的大部分内容既不符合物理现实（如果存在物理现实的话），也与身边人所描述的截然不同。

But there are states that you can be in where most of what you're perceiving is not in agreement with physical reality, if there is physical reality, or is different from what people next to you are saying.

这些就是我们所说的幻觉状态——在持续的一段时间内，大量这类感知错位持续发生。

And these are what we would think of as hallucinatory states, where it's a sort of ongoing period of time during which a lot of that is happening.

从大脑的角度来看，你认为这究竟是怎么回事？

What's your sense of of what that's about in brain terms?

当人们长时间经历他人无法体验的事物时，正如你所说，这种情况通常会被描述为幻觉。

When people experience things that other people don't experience, as you say, for a long period of time, that's typically when they're described as hallucinating.

对吧？

Right?

那么可能有什么不同之处呢？

And so what might be different?

很可能的不同在于，这些人在这些时刻的大脑中对预测产生了过度重视。

What probably is different is that there is, in the brains of these people at these times, an overemphasis on the predictions.

这有点像做梦。

It's a little bit like dreaming.

当我们做梦时，我们经历着独立于感官数据的知觉体验。

When we dream, we are having perceptual experiences that are independent of sensory data.

这种体验完全独立于感官数据，因为我们的感觉器官在梦境中基本处于关闭状态。

Now, this is completely independent of sensory data because our sensory organs are pretty much shut down during dreaming.

但你可以将感知与幻觉之间的连续体视为传入感官数据与大脑预测或解释影响之间不断演变的平衡。

But you can think of this continuum between perception and hallucination as an ever evolving balance between the incoming sensory data and the influence of our brain's predictions or interpretations.

当这种平衡过度倾向于大脑的预测，以至于它们不像其他人那样频繁地根据感官数据进行更新时，人们就会长时间地经历和感知到他人所没有的事物。

Tip the balance too far towards the brain's predictions so that they're not updated by the sensory data frequently or off as often as is the case for for other people, that's when the person will experience and perceive things that other people don't for prolonged periods of time.

因此，你可以将其视为感官数据的权重降低，而大脑解释机制或预测机制的权重过高。

So you can think of it as a down weighting of the sensory data and an overweighting of the brain's interpretive machinery or predictive machinery.

据我所知，进入幻觉状态的方式有很多种。

As far as I know, there are a lot of different ways in which you can get into a state of hallucination.

例如，你可能患有非脑部疾病，比如发烧——虽然发烧显然与大脑有关，但高烧会导致谵妄状态。

So, for example, you can have a disease or an illness not of the brain, just like a fever, which obviously happens all in the brain, You can be delirious because you've got a fever.

你可能极度疲劳。

You can be incredibly tired.

你可能患有某种常伴随幻觉出现的精神疾病。

You can have some sort of mental illness, a condition which often is associated.

此外，服用各类药物也可能导致幻觉。

And then you can take drugs of various kinds.

据我所知，能导致这种状态的药物不止一种。

And my understanding is there's more than one drug that can do this.

你的感觉是，所有这些导致幻觉状态的不同原因最终都会进入相同的幻觉状态吗？

Is your sense that all of those different causes of entering a hallucinogenic state end up in the same hallucinogenic state?

还是我们认为，这些增强感知方面、加剧幻觉的不同方式，本质上都是不同的机制？

Or do we think that these different ways of boosting the perceptual side of things, boosting hallucinations, are all basically different mechanisms?

我认为原理是相同的。

I think it's the same principles.

在所有能诱发幻觉的不同情境中，都适用预测压倒感官数据的相同原理。

The same principles of the predictions overwhelming the sensory data apply in all the different kinds of of the different situations in which hallucinations can be induced.

但我也认为它们会有所不同，因为在不同类型的幻觉中，不同种类或不同层次的预测可能会被改变。

But I think they would be different also in the sense that different kinds or different levels of predictions can be altered in different sorts of hallucinations.

从人们描述这些状态的经历中我们知道，人们可能产生的幻觉体验范围是非常多样化的。

And we know just from people's descriptions of being in these states that the range of hallucinatory experiences people can have is very varied.

例如，服用LSD的人所报告的体验，与患有所谓查尔斯·邦尼特综合征（一种常伴随黄斑变性或中央视野丧失而出现的幻觉体验）的人会有所不同。

So somebody who's been taking LSD, for instance, is going to report a different kind of experience to somebody who has what's called Charles Bonnet Syndrome, which is kind of hallucinatory experience that often follows macular degeneration or the loss of eyesight in the center of the visual field.

那些报告迷幻幻觉的人会描述诸如自我与外界分离的体验，以及充满变化和脉动元素等奇特视觉现象。

So people who report these psychedelic hallucinations will report things like a dissolution of the self from the outside world, strange visual experiences with with lots of changes and pulsating elements and so on.

患有查尔斯·邦尼特综合征的人会产生非常具体且有趣的幻觉类型，他们常会看到小人在房间里走动，这些小人常穿着中世纪服装，进行列队行进等活动。

People with Charles Bonnet Syndrome have very specific and and very interesting sorts of hallucinations where they often perceive little people wandering around the room, and often in medieval clothes, and engaging in marching and down, things like that.

这种幻觉非常独特且极不寻常，我不完全确定如何解释这种特定现象学，但它与迷幻药物引起的幻觉现象学截然不同，也与谵妄或发烧导致的幻觉不同。

This is very distinctive, highly unusual, and I'm not entirely sure what explains that specific phenomenology, but it is very different from the phenomenology that you would get for psychedelic hallucination, or even from a hallucination due to delirium or due to fever.

这是否意味着存在某种幻觉鉴赏家？

Does that mean there's like a connoisseur of hallucinations?

我可以写下我所看到的，然后他们可以读出来，就像闻一闻就能判断那样说'啊，没错'。

I could write down what I'm seeing, and then after they could read that back and say, you know, almost like sniff it and kind of go, oh, yes.

我想那可能是LSD导致的幻觉。

I think that's probably an LSD one.

或者说，通过简单的描述就能判断某人服用了什么药物或是什么导致了这种幻觉。

Or, you know, that you can sort of tell what someone's on or what's causing it from the simple description of what it is they're seeing.

是的。

Yeah.

确实如此。

Absolutely.

我认为，在研究感知的脑基础、视觉体验的脑基础乃至意识的脑基础方面，这是一个相对被忽视的机遇。

And this is, I think, a relatively neglected opportunity in studying the brain basis of perception, the brain basis of of visual experience, of consciousness too.

如果我们更关注现象学的细节，就能在大脑活动与视觉体验内容之间建立更丰富的对应关系。

If we pay more attention to the details of phenomenology, then we can generate richer mappings between what's going on in the brain and what's present in our visual experience.

我认为这是最引人入胜的问题之一。

I think this is one of the most fascinating questions.

你认为你是谁？

Who do you think you are?

你觉得自己是谁？

Who you think you are?

现在逐渐显现的是这种情况。

Now what seems to develop is this.

大多数人认为自我是位于皮肤之内的某种感知中心。

Most people think that eye is a center of sensitivity somewhere inside their skin.

大多数人都在他们的存在中感受到这一点。

And the majority of people feel this in their existence.

现在，谈话进行到这里，我通常会回到我的专栏，向神经科学家确认我的这些思考是否接近准确。

Now, this is the part of the conversation where I usually go back to my column and check-in with the neuroscientist whether I was even close to being accurate in my musings.

但实际上，我们从头到尾都在讨论这个专栏。

But, actually, we've been talking about the column the whole way through.

所以，我想以对听众来说更有趣的内容来结束。

So instead, I wanted to finish with something a little more interesting for you listeners.

关于所谓的'内省'。

Something concerning so called introspection.

我想在我们讨论这个话题时，我脑海中浮现出两种不同的内省。

So I guess there's two different kinds of introspection in my mind when we're talking about this.

一种是我们在开始时提到的关于'存在体验'的模型，我们相信外部世界存在，而我们在感知它。

So one is what we said at the beginning about the model we have of what it's like to be, and we have this we believe that what's happening is there's this world out there, and we're perceiving it.

但我想，从另一种内省的角度来看，感知也适用于我们如何看待自己，而非外部世界。

But I suppose in another sense, another sense of introspection, perception also applies to how we see ourselves, not how we see the outside world.