Asked by: Sally Rees, Newcastle
Pain is horrible, and you might think we’d be better off without it, but not so. On rare occasions, babies are born who can’t feel pain and this means they keep damaging themselves. Some bite through their own fingers and have to have their teeth removed; learning to walk leads to falls, cuts, breaks, and infections. Life can’t be lived to the full without pain. Pain protects your body with sensors in the skin, muscles, joints and internal organs. Two types of nerves take signals from these to the spinal cord and then to the brain’s specialised pain-processing centres. Fast delta fibres respond to sudden stimuli and produce a sharp pain so that you act quickly to escape the hot stove or to protect the cut knee. Slow C-fibres lead to dull, long-lasting pain that can prevent you moving an injured limb or joint, or force you to rest. The real mystery of pain is that you can pull your finger away from a hot stove far faster than you become conscious of the pain, leading some people to wonder why we need the conscious experience as well. Couldn’t we just be automata who avoid danger without actually having to suffer pain? This is part of the mystery of consciousness.
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