60秒科学:Amygdala's Acidic Aspiration Answer

Amygdala's Acidic Aspiration¹ Answer
A study in the journal Cell shows that the buildup of carbon dioxide when we stop breathing causes a pH change that signals proteins in the brain to force us to inhale². Karen Hopkin reports.

Maybe it’s happened to you. You think you have a fever. So you pop a thermometer in your mouth and try to breathe through your nose to get an accurate reading. But you’re totally stuffed up, so you experience this moment of complete panic because you can’t get enough air. Well, a new study in the journal Cell says you can thank your amygdala for that. Because this key member of the brain’s fear circuitry can directly sense suffocation³, and trigger feelings of terror.

The amygdala plays a role in responding to threats, and it can kick off a fight-or-flight reaction when it senses danger. Now, this brain region is packed with a type of protein that’s activated⁴ by acid, and seems to be involved in an animal’s response to fear. Well, suffocation is pretty scary and signals to the brain that something isn’t right. And it does so by activating⁵ this acid-sensing protein.

When an animal can’t breathe, carbon dioxide builds up, and boosts the amount of acid in the body. The acid, in turn, turns on this protein, which then hits the panic button and tells the animal to do something. Even if, during the Thanksgiving meal, it’s just to remind the animal to stop swallowing and take a deep breath.
 

1 aspiration   

n.志向，志趣抱负；渴望；(语)送气音；吸出

参考例句：

• Man's aspiration should be as lofty as the stars.人的志气应当象天上的星星那么高。
• Young Addison had a strong aspiration to be an inventor.年幼的爱迪生渴望成为一名发明家。

2 inhale   

v.吸入(气体等)，吸(烟)

参考例句：

• Don't inhale dust into your lung.别把灰尘吸进肺里。
• They are pleased to not inhale second hand smoke.他们很高兴他们再也不会吸到二手烟了。

3 suffocation   

n.窒息

参考例句：

• The greatest dangers of pyroclastic avalanches are probably heat and suffocation. 火成碎屑崩落的最大危害可能是炽热和窒息作用。 来自辞典例句
• The room was hot to suffocation. 房间热得闷人。 来自辞典例句

4 activated   

adj. 激活的 动词activate的过去式和过去分词

参考例句：

• The canister is filled with activated charcoal.蒸气回收罐中充满了活性炭。

5 activating   

活动的，活性的

参考例句：

• "I didn't say we'd got to stop activating the masses! “我并没说就此不发动！ 来自子夜部分
• Presumably both the very small size and activating influence of fluorine atoms contribute to this exception. 这大概是由于氟原子半径小和活性高这两个原因的影响，氟原子对这种例外做出了贡献。