Oftentimes when we cry, we feel a lump in the throat.
很多时候，当我们哭泣时，我们会感到哽咽。
Does alump actually form, or is there some other explanation?
难道是真的在喉咙中形成了块状物？或是有其它的解释？
The lump-like thing we feel when overcome by emotion has to do with how the nervous systemdeals with stress.
我们被情绪占据时所感受到的结块一样的东西与神经系统处理紧张的方式有关。
The part of the nervous system that handles stress is called the autonomicnervous system.
神经系统中处理紧张的部分叫作自主神经系统。

It controls bodily functions that we do not consciously control, such as digestingfood and pumping blood through the heart.
它能控制我们无意识地去控制的一些身体功能，比如消化食物和心脏泵血。
However, the autonomic nervous system is alsoimportant in dealing with emotional states.
但是，自主神经系统却在处理情绪状态时非常重要。
When an animal encounters a stressful situation, its autonomic nervous system kicks in to allow itto either fight or run away.
当动物面临紧张情境时，自主神经系统开始起作用，使动物选择战斗或是逃跑。
It does this by increasing the flow of blood and oxygen to thenecessary muscles.
这是通过增加输送至必要部位肌肉的血流和氧气来实现的。
The same applies to humans.
同样的情况也适用于人类。
Even when we experience emotions such asgrief or sorrow, the autonomic nervous system responds as it would to anger or fear by increasingthe flow of oxygen through the body.
即使我们怀揣着悲伤或伤感这类情绪时，自主神经系统也能作出响应，一如它在处理愤怒和恐惧那样增加全身的氧气输送量。
To increase oxygen intake, the autonomic nervous system makes us breath faster, and expandsthe glottis, the opening in the throat that allows air to flow from the larynx to the lungs.
为了增加氧气的吸入量，自主神经系统促使我们呼吸加快，同时使声门扩张。
Theexpansion of the glottis in and of itself does not create a lumpy feeling, until we try to swallow.
除非我们进行吞咽动作，不然声门的扩张本身不会让我们产生哽咽的感觉。
Since swallowing involves closing the glottis, this works against the muscles that open the glottis inresponse to crying.
因为吞咽涉及到声门的关闭，这与哭泣时开启声门的肌肉响应动作相反。
We experience the resulting muscle tension as a lump in the throat.
这时我们感觉到肌肉紧张，也就是喉中哽咽的感觉。