answers. It's both physiological and psychological. It's emotional and cultural. According

的答案。這既是生理上的，也是心理上的。既是情感的，也是文化的。根據

to the Association for the Study of Pain in 1979, pain is “an unpleasant sensory and

1979年，疼痛研究協會認為，疼痛是 "一種令人不快的感覺，也是一種痛苦的感覺"。

emotional experience associated with actual or potential tissue damage, or described in

與實際或潛在的組織損傷有關的情緒體驗，或在下列情況下描述：

terms of tissue damage.” But how did we arrive at this maybe-not-so-crystal-clear

組織損傷方面。"但是，我們是如何得出這個可能不是那麼清晰的，

definition? And what does pain theory teach us about our own bodies?

定義？疼痛理論又能給我們帶來什麼關於自己身體的啟示呢？

This question has been the subject of scientific and philosophical debate since Ancient Greece, but in the last

自古希臘以來，這個問題一直是科學和哲學爭論的主題，但在最近的

few centuries, it hinged on one question: where does pain come from physiologically?

幾個世紀以來，它取決於一個問題：生理上的疼痛從何而來？

Is there a specific set of nerves for pain? And if not, how do our regular nerves

疼痛有沒有一套特定的神經？如果沒有，那我們的常規神經是如何

know when something is painful or not painful? And is this even happening at the nerve level,

知道什麼時候會痛或不痛嗎？而這一切是否都發生在神經層面。

or is the brain more involved? Well, in 1811 a surgeon named Charles Bell attempted to

還是大腦的作用更大？在1811年，一位名叫查爾斯-貝爾的外科醫生曾試圖

answer that question. His idea was that specific nerve fibers send pain signals back to the

回答這個問題。他的想法是，特定的神經纖維會將疼痛信號傳回大腦。

brain, just like how any other sensory fibers like vision or smell send signals to the brain.

大腦，就像其他感覺纖維如視覺或嗅覺如何向大腦發送信號一樣。

We call this specificity theory today. And experiments by physiologists in the years

我們今天稱之為特異性理論。而生理學家在這幾年的實驗表明

afterwards seemed to back him up. Scientists identified specific receptors for all kinds

後似乎支持了他。科學家們確定了各種特定的受體。

of different sensations — including loads of different touch receptors embedded in your

不同的感覺--包括嵌入在您的身體裡的大量不同的觸摸感受器。

skin. Like Meissner's corpuscles are stimulated when something textured moves over our fingertips.

皮膚。就像Meissner's一樣，當一些有質感的東西在我們的指尖移動時，皮層就會受到刺激。

And those are different than Pacinian corpuscles which only sense signals for fine textures

而這些和Pacinian語料庫不同，Pacinian語料庫只感應到細微紋理的信號。

and high frequency vibration. Or how Merkel's discs help us determine things like pressure

和高頻振動。或者說，梅克爾的圓盤是如何幫助我們確定壓力等事情的？

while Ruffini corpuscles are probably responsible for sensing stretching in your skin. These

而Ruffini角質層可能負責感知皮膚的拉伸。這些

four types of receptors all sense mechanical touch, so we call them mechanoreceptors. Likewise,

四種類型的感受器都能感受到機械的觸覺，所以我們稱之為機械感受器。同樣。

the receptors for pain were named nociceptors — noci- for noxious, or painful. Then in

疼痛的受體被命名為痛覺受體--noci--代表有害的，或痛苦的。然後在

the early twentieth century, the main competing theory was pattern theory,

二十世紀初，主要的競爭理論是模式理論。

and it was pretty much the opposite. According to pattern theory, our nerves send signals

而這幾乎是相反的。根據模式理論，我們的神經會發出信號。

to the brain, and if the brain detects a familiar pattern of pain stimuli, the signals will

到大腦，如果大腦檢測到一個熟悉的疼痛刺激模式，信號將

be interpreted as pain. As anatomists kept discovering new sensory receptors, pattern

被解釋為疼痛。隨著解剖學家不斷髮現新的感覺感受器，模式

theory fell out of favor and specificity theory was more accepted. But specificity theory

理論失寵，特異性理論更被接受。但特異性理論

still had some issues. The most important was that pain isn't just the result of physical

還是有一些問題。最重要的是，疼痛不僅僅是身體上的結果

injury. It's a complex experience involving emotional, psychological, and cognitive factors.

傷。這是一種複雜的體驗，涉及情感、心理和認知因素。

So in 1965, two scientists published a paper describing what they called the gate control

所以在1965年，兩位科學家發表了一篇論文，描述了他們所謂的門控。

theory, which is the most popular model of pain physiology used today. This theory says

理論，這是當今最流行的疼痛生理學模型。這個理論說

that signals from the peripheral nerves first have to travel to three areas of the spinal

外周神經的信號首先要傳到脊柱的三個區域。

cord before traveling to the brain — the substantia gelatinosa, the fibers of the dorsal

脊髓在前往大腦之前--實質上的明膠，背側的纖維。

column of the spinal cord, and specialized cells called transmission cells in the dorsal

脊髓的柱子，以及在背側的被稱為傳輸細胞的特殊細胞。

horn as well. Those nerves from the mechanoreceptors and nociceptors all converge at this gate,

角也是如此。那些來自機械感受器和神經中樞的神經，都在這個門前匯合。

the substantia gelatinosa. If a signal from a nociceptor reaches a certain intensity,

實質性膠質。如果從神經中樞發出的信號達到一定強度。

the gate will open and that signal will be sent to the brain where it's interpreted

閘門會打開，信號會被髮送到大腦，在那裡它的解釋。

as pain. But if the gate is closed, the signal never makes it farther than the spinal cord.

作為疼痛。但如果閘門關閉，信號永遠不會比脊髓更遠。

So it wasn't a straight route from skin to brain after all, pain had to pass through

所以說，從皮膚到大腦畢竟不是一條直線，疼痛要經過

a gate first. Those researchers in 1965 suggested a few ways that the central nervous system

一門先。1965年，這些研究人員提出了幾種中樞神經系統的方法。

could close that gate, including moderation from the brain itself. This was an important

可以關閉這個大門，包括來自大腦本身的節制。這是一個重要的

step in pain theory that demonstrated how the brain and peripheral nerves both influenced

疼痛理論中的一步，證明了大腦和外周神經是如何同時影響到

how we feel pain. These days, we've added a few more details that give us a more complete

我們如何感覺到疼痛。這些天，我們又增加了一些細節，讓我們更完整地瞭解了

model of pain perception. We now know that not all nociceptors signal for the same types

疼痛感知的模型。我們現在知道，並不是所有的神經中樞都會發出相同類型的信號。

of pain.  We have receptors for high intensity mechanical pain, like getting punched, but

疼痛的感受器 我們對高強度的機械性疼痛有感受器，比如被打，但是... ...

different ones for high temperature, like stepping on a George Foreman grill.

高溫的不同，比如踩在喬治福爾曼烤架上。

"I clamped down on my foot. That's it. I don't see what's so hard to believe about that."

"我夾住了我的腳。就是這樣，我不明白有什麼難以相信的。我不明白這有什麼難以相信的。"

And these nociceptors aren't just in your skin. They're found in joints, muscles, and around organs.

這些神經中樞不僅僅存在於你的皮膚中 And these nociceptors aren't just in your skin.它們還存在於關節、肌肉和器官周圍。

Most of those receptors are attached to one of two major nerve types, either a Type A-delta

這些受體大多附著在兩種主要的神經類型之一，要麼是A型-Delta

fiber or a Type C fiber. More of those Type A Delta fibers are wider and covered in a

纖維或C型纖維。其中A型三角纖維更多的是較寬的，並且覆蓋著一種

substance called myelin that lets them send signals faster than the unmyelinated Type

稱為髓鞘的物質，讓他們比沒有髓鞘的類型更快地發送信號。

C fibers. And this lends itself to a cool physiology hack. Type A Delta fibers send

C纖維。這就為自己提供了一個很酷的生理學黑客。A型三角纖維發送

signals to the spinal cord faster, they're responsible for the first perception of pain,

它們能更快地將信號傳到脊髓，它們負責對疼痛的第一感知。

while the slow Type C fibers convey pain intensity. But the mechanoreceptors are myelinated too,

而緩慢的C型纖維則傳遞疼痛強度。但機械感受器也是有髓的。

so if you stimulate any of the non-painful touch receptors, that signal arrives at the

所以如果你刺激了任何一個無痛的觸覺感受器，信號就會傳到你的身體裡

substantia gelatinosa first, closing the gate. That's why rubbing a banged up elbow works.

實質性的膠質先，關閉大門。這就是為什麼擦撞肘子有效的原因。

You're taking advantage of the gate control theory. Then again it might all be in vain.

你這是在利用門控理論。不過話說回來，這一切可能都是徒勞的。

Life is pain, and anyone who says otherwise is selling something. Did I write this entire

生活就是痛苦，誰說不是，誰就是在賣關子。難道我寫的這整個

episode so I could sneak in a Princess Bride quote? You bet I did! Thanks for watching

一集，所以我可以偷偷在公主新娘的報價？我當然有！謝謝你看

this episode of Seeker Human. We've got more episodes like this one coming, so make

這一集的 "探索者人類"。我們還有更多類似的劇集，所以請在接下來的時間裡

sure you're subscribed to us on YouTube and following us on social media so you don't miss a single video.

確保你在YouTube上訂閱了我們，並在社交媒體上關注我們，這樣你就不會錯過任何一個視頻。