Picture this: you're baking cookies. As you lift the pan out of the oven, your bar e arm accidentally touches it. Ouch! Why did you feel pain? And how is your brain involved in sensing pain? We may not like pain, but our bodies need it as a warning system.
There are special receptor cells in our skin and bodies that are sensitive to certain stimuli (刺激). These cells are called "nociceptors". When a nociceptor gets exposed to a painful stimulus, it sends a message into the brain. The brain processes that information, and then pain is felt. Think about a time when you've stubbed your toe. There doesn't seem to be a delay between hitting your toe and then feeling pain: it feels like it happens at the same time.
If we have an injury, pain alerts us to rest and let the injury heal. If we stand too close to a fire, pain tells us to move away. Not being able to feel pain can be dangerous. Some people can feel sensations like touch, but they cannot feel pain. Without feeling pain, they cannot listen to their bodies when they need to rest or heal.
On the other hand, the brain sometimes processes pain where there isn't any actual injury to the body. Here's a famous story: a man stepped on a nail. It went through the bottom of his shoe, and he felt like he was in horrible pain. When the doctors removed his shoe, they found that the nail was between his toes! It hadn't gone into his foot at all. So his brain perceived pain to match the experience.
Without pain, we might not know when we could need to rest. We might not know if we were in danger of hurting ourselves. However, it is an important part of human life and survival!
A. Pain is not fun to feel. B. Pain is a response to a stimulus. C. Our brains use sensory information to interpret the pain that we feel. D. Even though pain is an unpleasant feeling, it is necessary for human survival. E. All of this signal sending and processing happens faster than we can perceive. F. It is an important function of our brain, telling our bodies when something is wrong. G. However, the visual information tricked his brain into thinking that there was cause for alarm. |