When you're sad, so angry you could cry, or trying not to weep at that ASPCA commercial again, you’ve probably felt a big lump in your throat during emotional moments. Why?

According to clinical psychologist Ad Vingerhoets, it’s all part of our natural fight-or-flight response. When humans feel stressed, our bodies prepare us to physically take on the obstacle or flee the scene. Our heart rate increases, our blood pressure skyrockets, and our respiration rate increases. "The faster rate of respiration impacts the muscle that controls the opening of the throat called the glottis (middle of the larynx)," Vingerhoets told IFLScience. "The glottis expands to allow more air in during the preparation for fight or flight."

The glottis is where that lump comes in. Though the jury is still out on the exact reason the lump forms, it has something to do with muscle tension and the glottis. The first theory is that when you try to swallow (a process that requires closing the glottis) against that expanded glottis, you’re creating muscle tension, and thus discomfort. Theory number two is that the lump mainly occurs when you’re trying not to cry, which means you’re trying to constrict the muscles in your throat while your glottis is trying to expand.

The next time you find your throat burning during an emotional moment, the best thing you can do is to take a couple of deep breaths and try to relax. (Easier said than done, we know.)

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