Hey! Vsause. Michael here. And today we are going to talk about yawning.
嘿!Vsauce。這裡是Michael。今天我們要談談打呵欠。
Why do we yawn? And why is yawning contagious? How come when I see someone yawn or even think about it makes me kind of want to yawn?
為什麼我們會打呵欠？為什麼打呵欠是會傳染的？為什麼當我看到某人打呵欠，或甚至想著它時會讓我有點想要打呵欠？
First things first: definitions. When you yawn, you inhale air and stretch your eardrums. That's why your ears pop when you yawn. Now, if you yawn and at the same time stretch your whole body, that is called pandiculation.
要事優先：定義。當你打呵欠時，你吸入空氣並延展你的鼓膜。那就是為什麼當你打呵欠時你的耳朵會發出啵的一聲。現在，如果你打呵欠並同時伸展你全身，這叫做伸懶腰。
A common misconception about yawning is that people yawn when they need more air, more oxygen, but studies have shown that no matter how much oxygen is in the air around the person, they won't yawn more or less frequently. And when people exercise and their bodies do in fact need more oxygen, they don't yawn more often. Instead, research has shown that our first answer most likely lies in being cool.
有關打呵欠的一個常見錯誤想法是，人們在他們需要更多空氣、更多氧氣時會打哈欠，但研究顯示不論那個人周遭空氣中的氧氣有多少，他們都不會因此較常、或較不常打呵欠。當人們運動而他們的身體確實需要更多氧氣時，他們不會更常打呵欠。反而，研究顯示我們的第一個答案最有可能在於冷卻。
When you are exhausted, tired, deep brain temperatures increase. But your brain is like a computer. It operates best at a very specific temperature. And so, yawning, bringing all this outside air in through your ears and your mouth cools your facial blood and actually helps cool down your brain.
當你筋疲力竭、疲累時，大腦深處溫度升高。但你的腦就像台電腦。它在一個非常特定的溫度下運作得最有效。所以，打哈欠，帶入這外頭全部的空氣穿過你的雙耳和嘴巴，讓你臉部血液降溫，並確實幫助冷卻你的腦袋。
This phenomenon is particularly easy to observe when parakeets yawn. Researchers have found that parakeets only yawn within a very specific range of temperatures. Too cold outside, an yawning would cool the brain too much; too hot, an yawning would actually warm it up.
這個現象在長尾鸚鵡打呵欠時特別容易觀察到。研究員發現長尾鸚鵡只會在一段非常特定的溫度範圍內打呵欠。外面太冷，一個呵欠會讓腦部冷卻過度；太熱，一個呵欠事實上會讓腦部加溫。
Parakeets are perfect test subjects for this effect, because they yawn just like you and me except they don't exhibit contagious yawning. If you show a person a video of other people yawing, it's likely that the person watching will yawn his or her self, unless you put an ice pack on their forehead keeping their brain cooler. Seriously, the University of Albany has found that people contagiously yawn less frequently when they have ice packs on their head, which means that yawning to cool your brain isn't just for the birds.
長尾鸚鵡是這種作用的完美試驗對象，因為牠們就像你和我一樣打呵欠，只是他們並沒有顯示出具傳染性的呵欠。如果你給一個人看一段其他人打呵欠的影片，很有可能看影片的人他或她自己也會打呵欠，除非你放個冰袋在他們的額頭上讓他們的頭腦保持更冷卻。說真的，Albany大學發現人們在頭上放有冰袋時，會比較少受到傳染而打呵欠，這表示打呵欠來冷卻你的腦袋不只在鳥類身上有效。
Studies have shown that yawning also increases blood pressure, stretches facial muscles, and increases focus. When you pandiculate, you stretch all of your muscles, making them better ready to be used at any moment. So when it comes to a herd of prey animals, contagious yawning makes sense, because a herd that yawns together stays alert together. Under this theory, yawning is advantageously contagious, because that first animal to yawn acts as a sort of reminder to the rest of the herd to keep themselves ready and alert. But of course, when we say that yawning is contagious, we don't mean like a disease. Instead, it's a bit more closely related to empathy.
研究證明打呵欠也會升高血壓、伸展臉部肌肉並增加專注力。當你伸懶腰，你伸展你所有肌肉，讓他們更充分準備好在任何時刻被派上用場。所以當提到一群獵物時，傳染性的呵欠就說得通了，因為一群一起打呵欠的獵物會一起保持警戒。在這理論之下，打呵欠是有利地具傳染性的，因為第一隻打呵欠的動物扮演一種對獵物群中其他動物有點像是提醒者的角色，讓牠們保持機靈及警戒。但當然，當我們說打呵欠是有傳染性的，我們不是指像一種疾病。而是它更密切地與同理心相關。
Sympathy is when you are concerned for others, where you wish someone is better off. Empathy is the ability to recognize and share the emotions that other people feel. Emotional contagion is when the emotions of people around you influence the way you feel without you even having to separate yourselves from them, like when being around happy people lifts your spirit, or how anger and fear can lead to mob mentality. Now, children with autism who exhibit impaired social interaction and communication yawn less frequently than other children when viewing videos of people yawning.
同情心是當你關心其他人時，你希望某人生活能更好。同理心是能察覺並分擔他人所感受到的情緒的能力。情緒傳染是當你周遭人們的情緒影響你的感受，你甚至不必讓自己和他們區隔開，像是當在開心的人身邊時會提振你的精神，或是怒氣和恐懼可以如何導致暴民心理。現在，顯示出有較弱的社交互動及溝通的自閉症孩子在觀看別人打呵欠的影片時，比其他孩子更少打呵欠。
So is yawning an emotional contagion, or is it about empathy? Last year, the University of Pisa found that yawn contagiousness is greatest with family, and then friends, and then acquaintances and lastly, strangers. And a study at Leeds University brought in participants to take a test that measure how empathetic they were. But before the test began, amongst them was one person who worked for the researchers, and this person yawned every minute for ten minutes. Interestingly, the people who wound up scoring the highest on the empathy test were also the ones who contagiously yawn the most.
所以呵欠是一種情緒傳染，還是跟同理心有關呢？去年，比薩大學發現呵欠傳染性在家人之間最強，接著是朋友，再來是熟人，然後最後是，陌生人。而里茲大學的一項研究引進受試者進行一項測量他們有多具同理心的測驗。但在測驗開始之前，他們之中有一個人是為研究員工作的，這個人連續十分鐘每分鐘都打呵欠。有趣的是，那些最終在同理心測驗得到最高分的人們同樣也是打最多傳染性呵欠的人。
Let's talk more about animal yawning. What fascinates me so much is that animals across many species all yawn, but they do so for different reasons. Animals like guinea pigs and some monkeys yawn to intimidate and show their sharp, scary teeth. Some penguins yawn to attract mates. And when snakes yawn, it seems to be about realigning their jaws and opening their tracheas to breathe better after a big body-disfiguring meal. Fish yawn more frequently when water oxygen levels are low, or water heat levels are high.
再多談談動物打呵欠。讓我如此著迷的事情是，跨越許多物種的動物全都會打呵欠，但他們為了不同的理由做這件事。像是天竺鼠和一些猴子的動物打呵欠來威嚇和露出他們尖銳、可怕的牙齒。有些企鵝打呵欠來吸引配偶。當蛇打呵欠時，似乎是要在一頓讓身材走樣的大餐後重新排列牠們的下巴，並打開牠們的呼吸道好能更順暢地呼吸。魚在水中含氧程度低、或是水中熱度高時會更頻繁地打呵欠。
So when you yawn, you're participating in the behavior shared across all kinds of animals,
but most likely you're yawning for purposes unique to your species, us humans. And what's really cool is that yawning is most likely an ancient signal telling the rest of us humans: "Let's do this! Let's survive!"
所以當你打呵欠時，你正參與一種跨越所有動物種類所共有的行為，但最有可能的是你正為了一個對你的物種、也就是對我們人類來說很特殊的目的而打呵欠。而很酷的事是打呵欠最有可能是一種古老的信號，告訴我們其他人類：「來打呵欠吧!來活下去吧!」
And as always, thanks for watching.
接著一如往常，感謝收看。
