optical illusions get all the attention.

無不聚焦於視錯覺

But the whole body you have

但是，你所擁有的身體

can be fooled and can fool the brain.

可能被欺騙 甚至連大腦都受騙

One of my favorite physical illusions

我最愛的肢體錯覺之一

is the thermal grill illusion.

就是「熱烤架錯覺」

and you can do it right at home.

你在家就能做這項實驗

I have some hot dog halves in an ice bath.

這裡有些切半的熱狗泡在冰水裡

I also have warm hot dog halves.

微波爐裡也有些溫熱好的切半熱狗

Now what I'm going to do is marry the halves together

現在，我將兩邊的熱狗拼湊起來

so that they alternate, warm, cool.

依序排列 溫的熱狗，冰的熱狗

Warm, cool.

先溫的熱狗，再冰的熱狗

When I'm done, I will have a torture device.

完成排列之後，我就會有一個虐刑裝置

But not one that hurts your body,

但並非會傷害人體的那種

one that hurts your mind. [laughing]

而是能扭曲你的思維

[electronic music]

心田

♪ ♪

羅珊娜‧潘西諾 -哈囉，麥可

Rosanna Pansino. - Hello, Michael.

歡迎蒞臨心田節目

- Welcome to "Mind Field." - [chuckles]

羅珊娜‧潘西諾是 YouTube烹飪節目

- Rosanna Pansino is the host of the YouTube cooking show

Nerdy Nummies的主持人

"Nerdy Nummies."

大腦蛋糕

- Brain cake. Mmm.

我覺得她是最適合擔任

- So I thought she would be the perfect candidate

熱狗錯覺品嘗的來賓

to try out our hot dog illusion.

好吃

- Oh, yeah.

你沒看見或聽見我剛才做的事情吧？

- Now you didn't hear or see anything I just did, right?

- 對 - 很好

- No. - Good, all right.

妳來是為了享受我們的招待

Well, you are in for a treat.

我需要妳將手臂內側

What I want you to do is take the bottom of your forearm

- 平放著，需要掀起袖子 - 好

and place it, skin showing... - Okay.

直接放在熱狗上方

Right onto these hot dogs.

- 感覺如何？ - 好燙

- Oh!

現在，碰觸每一片熱狗

- What'd you feel? - Ouch.

剛剛真的很痛

But now touch them individually.

冷的，熱的，冷的，熱的 冷的，熱的

- Oh, like, hurt.

但是沒有任何一片感覺像 一起碰觸時那麼燙

Cold, warm, cold, warm, cold, warm.

- 為什麼呢？ - 我不知道，魔術嗎？

- But none of them is as hot as they all felt together.

- 到底怎麼了？ - 我能試試嗎？

So what's going on? - I don't know. Magic?

我當然能試啊，這是我的節目

What's going on over here? - Can I try?

- 對啊，試一試 - 好燙

Of course I can try. It's my show.

剛才進行的實驗

- Yeah, do it. - Oh, yeah.

就是所謂的「熱烤架錯覺」

What we've built here is a version

而這項實驗之所以仍有需多爭議

of the thermal grill illusion.

是因為這種接觸會造成疼痛感

And for reasons that are still being debated,

或許是因為人類的觸感神經 特別是接觸到熱及冷的物體

this can cause a sensation of pain.

使觸感神經反映出劇烈的疼痛感

Maybe the sensors we have, specific to hot and cold,

而如著火般的冷熱感受

are both also specific to extreme pain.

讓身體覺得「燙！燙！燙！」

And getting them to fire right together

若這種感受非常靠近

makes the body think, "Whoa, whoa, whoa."

- 意思就是快逃 - 紅色警戒

If they're both firing that near to each other,

- 對，紅色警戒 - 剛才我的手臂就是這種感覺

that means get away. - Red alert.

因此，我想要說的就是

- Red alert, yeah. - That's what my arm did.

這是一項傷害人的好方法

- So what I'm really trying to say is

因為不會留下任何傷人的痕跡 或是導致任何損傷

this is a great way to hurt someone

- 聽起來真奸詐 - 在家試試看吧

without there ever being a mark or any actual damage.

人體表面

- That's pretty sneaky. - Do try this at home.

潛藏著數百萬個末梢神經

[tranquil music]

這些神經的功能，就是傳送接觸物體後 產生的感覺訊息到大腦

♪ ♪

但是，遇到某些狀況時，這些神經

- The surface of the human body

並不需要受到末梢神經觸感而產生感覺

contains millions of nerve endings

聽過「痛覺同感」嗎？

that send touch-related sensory information to the brain.

最有名的痛覺同感

But in some cases, those sensations

稱為「擬娩症候群」

don't even need to be generated by nerve endings.

意思就是

Ever heard of sympathy pain?

準爸爸出現的懷孕癥狀

The most well-known type of sympathy pain

準爸爸確實能體會

is called couvade syndrome.

懷孕中老婆

It's when a pregnant woman's husband

經歷的各種痛楚

goes through labor pains.

像是增肥、失眠

Husbands can actually sympathize

噁心、情緒起伏等等

with their pregnant wives so much

痛覺同感又稱為「聯覺疼痛」

that they experience the same problems,

透過眼見別人受害而產生的痛感

such as weight gain, insomnia,

身障者最能感受到這點

nausea, mood swings, et cetera.

因為受創的經歷，使得他們的大腦

Sympathy pain is also known as synesthetic pain.

對於別人受創時，更能體認此痛楚

It's pain sparked by seeing someone else get hurt.

他們甚至對於已不存在的四肢

- Ooh!

仍然感受到痛楚

- Amputees can actually be more susceptible to it

這種行為，稱之「幻肢疼痛」

because experiencing trauma can make the brain more sensitive

但是，最令人驚訝的方式

to other people's pain.

或許是大腦與痛感間的關係

Amputees can also feel pain in the limb

能受到「反安慰劑反應」所控制

that is no longer there.

聽過「安慰劑反應」嗎？

That is known as phantom pain.

它就像是能治癒人類疼痛的

But perhaps the most surprising way

假痛藥丸

that the brain and pain interact

因為它們真的能治癒那種痛楚

can be demonstrated by the nocebo effect.

那麼，現在

Have you ever heard of the placebo effect?

即將進行一項完全相反的實驗

It's like when a fake pain pill

若一物體有所期望

actually cures a person's pain

他們將經歷一段不愉快的事情

because they have a positive expectation it will work.

像是：感受痛楚

Well, today,

甚至是心理層面的痛楚

we're demonstrating the exact opposite.

我們已告知受測者 他們將參與一項實驗研究

If a subject expects

並藉此以非侵入性骨密度儀測試結果

they're going to experience something unpleasant,

其實這台儀器是假的

like pain, will they feel it

那是我們用檯燈製造的假儀器 一台空氣壓縮機

even if it actually exists only in their mind.

加上一個用來逗貓的

We've told our subject that she's participating in a study

10元雷射筆

to test a non-invasive bone density scanner.

這儀器不會造成傷害

But actually, it's a totally fake machine

也就是不會有任何感覺

that we built from a desk lamp, an air compressor,

根本就不痛啊！ 這樣根本行不通

and the kind of $10 laser pointer

但是，這種儀器

you might tease your cat with.

真會讓受試者感覺到疼痛嗎？

It doesn't cause physical pain, or for that matter,

往這邊走

physical sensation of any kind.

慢慢走，並且找個位子坐下來

It doesn't hurt at all. You guys, this doesn't work.

妳準備好可以開車的時候

[laughter]

通知我們，我們會協助你的，好嗎？

But will the expectation alone

好，謝謝妳

make our subject think she's feeling real pain?

首先，我們必須讓受測者

- So come on in here.

預期即將經歷的痛感

Just go ahead and take a seat right there.

因此我們的演員 即將演出讓她驚恐的一幕

And then when you feel ready to drive,

抱歉，潔西卡 這麼做都是為了科學證明

just let us know and we'll dismiss you, okay?

妳做完了嗎？

- Okay. Thank you.

做完了，我只是需要一些時間休息

- First, we have to make our subject

- 休息完後，我就可以離開 - 妳剛才做了什麼療程？

expect to experience pain.

就像是鎖定目標的雷射器

And to do that, our actors are going to scare her a little.

它用來測量骨密度

Sorry, Jessica, this is for science.

- 會痛嗎？ - 會

- So are you already done?

看到她的表情

- Yeah. I just, you know, need a minute.

我們似乎成功讓受測者建立

Then I'll be good to go. - What'd you do?

接下來的預期恐懼

- It's like a targeted laser.

- 潔西卡，輪到妳了 - 祝我好運吧！

It tests bone density.

問題是，實際進行測試時

- Did it hurt? - Yeah.

這個根本不痛的假儀器

- By the look on her face,

真的會讓她感到疼痛嗎？

it appears we have successfully primed our subject

- 這位是潔西卡 - 嗨！

for what's to come.

嗨！潔西卡，請進

- Okay, Jessica, we're ready for you.

妳不坐嗎？

- The question is, when put to the test,

診療室內的一切

will she actually feel pain

包括醫療設備、醫療補給品

when there is really none there.

甚至到我們假扮護士的行為舉止

- This is Jessica. - Hi.

全都是為了讓潔西卡信以為真

- Hi, Jessica. Come on in.

為了誘發她心理層面的痛覺

Won't you have a seat?

我們正在進行儀器測試

- Everything in this room,

這並不具侵略性 我們只是想了解

the medical equipment, the hospital supplies,

該儀器的副作用以及病患的反應

even the demeanor of our fake nurse,

我需要妳具體說明

is designed to play on Jessica's mind.

妳待會所感覺到的一切

To psychologically induce the anticipation of pain.

並且，仔細感受妳所感覺到的疼痛

We're testing out some equipment.

以及疼痛的層次

It's not invasive. We need to measure

注意我們是如何跟她說 她待會感覺的痛的程度

the side effects and patient reaction.

藉此，讓她更能預期疼痛的心情

And I want you to be really descriptive

我等一下會給妳一顆球

about what you're feeling.

- 擠壓它作為妳感覺疼痛的程度，好嗎？ - 好

And pay close attention to the pain that you feel

若中途想停止，它馬上就會感應到

and how it grows.

- 好 - 可以嗎？

Notice how we are suggesting that she will feel pain,

準備好了嗎？

further raising her expectations.

感覺...溫暖

- I'm gonna give you a ball to squeeze

有一點...刺痛感

for pain management, okay? - Okay.

只過了七分鐘

- And any time you want to stop, it stops right away.

她就已經確實感覺到疼痛

- Okay. - Okay?

其實根本就沒這回事

- You ready?

切記，我們的骨密度儀是假的

[machine humming]

而那道雷射光根本就不會產生任何熱能

- It's definitely warm. - Uh-huh.

現在...感覺有些不適

And, like, like, tingly.

- 需要我關掉它嗎？ - 不，不用

- After only about seven seconds,

- 現在已使用了30秒 - 好像被針刺

she's already feeling a physical sensation on her skin,

- 針？ - 有一根針，很...

where there is none.

- 非常...熱 - 現在變熱了

Keep in mind, we tested our fake bone scanner,

- 已使用45秒 - 並不...

and the light emits zero heat or feeling of any kind.

- 好，我現在關掉它 - 好，謝謝

- Yeah, now it's-- doesn't feel that great.

妳一開始說溫暖，之後說變熱

- You want me to turn it off? - No, it's okay.

就像是一開始溫溫的 然後變得灼熱

- We're at 30 seconds. - Really, like, stinging.

最後甚至像被針刺到

- A sting? - A sting and, like,

依照這個疼痛程度表，妳能指出

really, really hot. - Now it's hot.

剛才感覺到的疼痛程度嗎？

We're at 45 seconds. - Yeah, it doesn't--it's...

介於六與七之間

- Okay, I'm gonna turn it off. - Okay, thanks.

依據疼痛量表

- You described warm turning to hot.

她剛才經歷了深刻的疼痛感

- It was, like, warm and then that, like, heat grew

決定權完全在於妳 我們即將進行下一個階段

into more of, like, a sting.

這階段感受會更加深刻

- On this pain scale, could you point to

還有幾個階段需要進行？

the amount of pain you were feeling?

還有五個階段

- Between a six and a seven.

- 五個階段？ - 對，五個階段

- According to the pain assessment scale,

- 我的天啊！ - 但是，再次強調

she experienced significant pain.

決定權在於妳

This is completely up to you, but we can move to level two,

喔...好...繼續吧

which is slightly more intense.

接下來是反安慰劑效應測試

- How many more levels are there?

她會覺得自己即將會更加疼痛嗎？

- Uh, there's just five.

準備好了嗎？

- There's five levels? - There are five.

切記，第二項測試也是假的

- Oh, my gosh. - But again,

我們並未做任何改變

you're in the driver's seat.

意思就是，實際上根本毫無痛覺

- Uh, yeah, sure. Let's do it. [chuckles]

一開始，它的強度

- Here's another test of our nocebo.

應該會比上一次還高

Will she feel an increase in her level of pain

就像是，一開始就覺得刺痛

if she expects to? - You ready?

很快地，她說第二階段 真的比較痛

- Mm-hmm. [machine humming]

已開始15秒

- Keep in mind, level two is fake.

感覺真的...好熱

We're not doing anything different than before,

就像皮膚被刺穿般的痛

meaning nothing is happening to her.

刺得多深？

- So, yeah, it started off higher

- 30秒 - 我不知道，就像...

than the last time, I think.

刺穿了二分之一英吋 或是刺穿了一英寸

It's definitely, like, already stinging.

感覺...非常地...熱

- Immediately, she reports increased pain on level two.

有一種灼熱感

It's 15 seconds.

整隻手臂彷彿著火般的熱

- It feels really, really, really hot and,

- 隨時都可以停止 - 妳想停止嗎？

like, penetrating.

- 好 - 好的，關掉它

- How deep? - Um...

- 妳需要衛生紙嗎？ - 好，謝謝你

- 30 seconds. - I don't know, like,

不用客氣

1/2 and inch or, like, an inch.

能請你說出第二階段的疼痛程度嗎？

Yeah, it is... it's very hot.

大概是九又二分之一

Um, like burning.

一切的演出，深具影響力

Like my whole arm is, like, on fire.

反安慰劑效應測試，讓受測者認為

- We can stop at any time. - You want to call it?

她幾乎能感受到最大的痛感

- Yeah. - Okay, we're off.

其他受測者的感覺不盡相同

- Do you need a tissue? - Yeah, thank you.

感覺肌肉...

- You're welcome. - [sniffs]

有種燒起來的感覺

- Could you rank for me how you felt at level two?

- 停 - 感覺如何？

- Like 9 1/2.

疼痛感，大約在七分

- The power of suggestion was so strong,

其實，現在覺得比上一項測試

our nocebo caused our subject to think

更加刺痛

she felt almost the worst pain imaginable.

其實，我對於她的反應 覺得挺訝異的

Other subject felt different imaginary sensations.

有一些受測者的感覺

- The muscles are kind of, uh,

是由內心而生的

kind of burning a little bit.

我要關掉它了，已使用45秒

- Stop. - How did that feel?

請說明你剛才的感受

- That was, like, a seven.

感覺有些刺痛

Actually it's tingling a lot more now

就像起雞皮疙瘩的感覺

than it was before.

那麼，原來這位

- I was surprised at the intense reaction

經歷過九又二分之一疼痛感的受測者 會覺得怎樣呢？

some subjects had to a feeling that was created

若知道全部的感覺其實都是心理影響時 她做何感想？

only in their minds.

讓我向妳訴說

- Look, I'm gonna stop it now. That was 45 seconds.

今天我們所做的一切

Describe for me the sensations that you were having.

這是一項心理層面的實驗

- It felt like a little prickle

而這項設備並未對妳造成任何傷害

like when you get goose bumps.

這只是一台會發出噪音的機器

- What about our original subject

檯燈上，也只是一隻雷射筆

who experienced a severe 9 1/2 on the pain scale?

- 真的？ - 真的

How will she feel when she learns it was all in her head?

- 我的天啊！ - 妳一直都很安全

I want to debrief you on everything

- 我們什麼都沒做 - 天啊！

that we're up to today.

這是一項痛苦程度的調查

So this is a psychology program,

- 真的奏效了 - 剛才我好害怕

and this equipment is not doing anything to you.

我差一點就...

This is just a machine that makes noise.

就要說：我不想繼續了

And that's just a laser pointer on a lamp.

我差一點就想離開這了

- For real? - For real.

妳的確有說，妳覺得像被針刺

- Oh, my God. [laughing] - You were never in danger.

那妳當時感受如何？

- We didn't do anything to you. - Oh, my God.

無論是真是假，我的確起雞皮疙瘩

- This is an investigation in pain anticipation.

或是只是緊張 我也分不清楚

- Yeah, that worked. - I was so scared. [laughing]

我心裡知道

I was so close to, like, going to, like,

接下來說不定會很痛

just say, "You know what? I changed my mind."

即將感受到痛感

I was so close to leaving.

我的確感覺...像是...

- You did say that you felt a prickle.

整支手臂著火般

- Uh-huh. - How do you feel about that?

- 真的嗎？ - 真的

- Whether it was really I did get goose bumps

由於過程極度逼真

or I was nervous, which is why I felt it.

以致於這位受測者仍然想像著疼痛的感受

I know, as a person, like,

即便她已知道一切的實驗都是假的

if I think there's going to be pain,

這個效應稱為「反安慰劑效應」

I'm gonna feel something.

為一種全由心智所產生的 負面效應

- I do still feel, like, kind of like

周遭環境的影響力

a burning sensation on my arms.

實在是非常合理