system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: If someone has a limb amputated, what causes them to feel like it's still there after it's gone? ie. ghost limbs?

If the doctor cut the nerve endings off (which I assume what would happen), why would they still feel the limb that is no longer there? My grandmother (who is 80 years old currently), allegedly had her mother experience this. She told me that her mother's amputated limbs (due to complication with diabetes) had the doctor "curl up all of the nerve endings that were in the leg into one area (I'm guessing like a ball of nerves at the stub?), and then closed it up". This happened to both legs, and both legs felt pain randomly and she felt the sensation to rub them. Is this even true/possible or is she remembering incorrectly because she is so old?
gpt
The pathways in your brain are strengthened with use. That's why toddlers fall down so much: it's not just that their legs are tiny, it's that they've never done it before. After a year or two they can walk all the time. The neural connections for the muscles and nerves in their legs are reinforced. 

Now imagine all the things you can do with your arm. Eat food, catch a ball, shake hands, drive, type. A million little things you don't even have to think about anymore, because you've done them your whole life. That experience, that "muscle memory" and object permanence and fine motor control, none of that is actually your arm. It's all in your brain. Those neural connections are strong because they're constantly used.

Now imagine you lose your arm. All those memories of everything that you do with your arm, all the sensations and experiences you normally don't even think about, are still there. They're all right there in your brain, even after your arm is gone. You reach out to pick up a glass of water and the pathways for reaching and grabbing activate, even if there's nothing for them to connect to. If you don't think about it, or even sometimes if you do, the motor and sensory pathways that you're expecting to use will fire, and your brain fills in the blanks of what it's expecting to experience.