Which nerves are capable of regeneration

They just don't do it very much or very fast. This has been a problem for people who injure their nerves or nervous system. Damage to the nervous system can often cause a person to be paralyzed.

These broken nerves can't regenerate their neurons to fix themselves. Without these neurons, it becomes difficult or impossible to move arms or legs or even to breathe. Under just the right conditions, stem cells top can become nerve cells bottom. New research shows that stem cells might be able to help this problem by becoming neurons themselves.

What are stem cells? Well, each cell in your body has a purpose. Muscle cells contract and make your muscles move your body. Skin cells form a barrier between the inside of your body and the outside world. Nerve cells send information and tell your body what to do. Stem cells don't have a purpose. Well, not yet at least. All cells start out without a purpose. They have no job. But all cells go through a process called differentiation. Differentiation turns them from a cell without a job into a specific type of cell that has a specific purpose — like a muscle cell or a neuron.

You might ask, "So what? Scientists think that if they can tell stem cells to turn into neurons, then they might be able to help paralyzed people move again.

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