|MadSci Network: Medicine|
In my opinion people cry due to emotional pain bacause the mind does not differentiate between physical pain and emotional pain. Despite the moral dictations of our German and English culture which prohibits displaying emotions such as fear and grief, our minds still feel it and display it physically. In fact, I believe crying happens more often in association with emotional responses than with physical pain. As a baby incapable of actually shouting for help, human infants have but one automatic reponse that communicates need or distress : Crying. There are three basic physical reponses to stress/threat : Fight, Flight and Cry. These are automatic neotonous responses that all humans posess. When your brain gets scared or determines loss or threat of death or some other bad news, it activates the automatic stress response center in your brain. You get mad, you run, you cry, or all three at once. These reactions would have given early man a better chance of survival. Running from the threat, calling for help (crying) or fighting the threat. These are basic answers and you might have wanted more specific explanations, but when you get down to the basics, this is pretty much all there is.
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