Why Do We Feel Pain
Channel: Science Saturdays
Date: 2014-02-02

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Pain is quite painful to say the least, so why do we feel pain? Pain is one of the ways that our body tells us that we may be or are in danger of tissue damage. But what tells our body the difference between just touching something and touching something that is actively causing damage? All around our body we have two different types of neurons. The neurons responsible for our sense of touch are our sensory receptors, and when a stimulus comes in contact with this type of neuron such as a light touch or tap, an electrical signal is sent through the nerves in our body and ends up at our brain where the signal is analyzed. Our second type of neuron is called a nociceptor neuron, and this is what senses damage. When there is enough pressure or energy to break the "pain threshold," our nociceptors send a different kind of signal through our nerves that is interpreted as pain, alerting us of damage. This is why you don't feel pain when just touching something, but why you do feel pain when smacking it against something. The sensation all depends on the force behind the action. So that's all there is to it. Shortest video ever, right? Not exactly. Although that's all of the science behind the sensation itself, there's still a whole lot of other questions to be answered, such as the following. Suppose you break a bone by exerting a lot of force on it. You feel a significant amount of initial pain, but if you were to just lightly touch it a little after the incident, it would still hurt. Why would such a little amount of force hurt then when it normally wouldn't? When cells are damaged, they secrete chemicals called prostaglandins. This chemical decreases the amount of force needed to break the "pain threshold," in turn making light motions hurt more than they should, sort of saying, "Hey. I'm still not fixed, fix me." But in the case of an incident like this, you would probably take a painkiller like ibuprofen or Advil. But how do painkillers work? Painkillers block production of the chemicals that damaged cells secrete, so they aren't really getting rid of the pain, but rather just increasing the amount of effort it takes to cause the pain. So pain seems great! It alerts our body of damage and keeps us safe, most of the times that is. Pain can be so unbearable at times that people and animals have a syncope, also know also fainting. Fainting is extremely dangerous in the event that one is damaged, as once somebody faints due to extreme pain they either fall prey to their predator's hands, or they allow their situation to worsen, further damaging their cells and their chances of survival. So sure, pain can be somewhat helpful at times, but pain is ultimately our body's somewhat flawed attempt at alerting us that we are in danger of physical damage.

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