If I can create synthetic neurons, I am going to use them for people who has motor neuron diseases.
Motor neuron diseases can happen because of problems in the nervous system. Motor neurons are neurons that executes orders that came from interneurons. For example your sensory neurons “saw” a scary thing, they are going to send this message to interneurons. Interneurons are going to process that message into responses. After that processing, interneurons are going to send this response to motor neurons. So your motor neurons are going to activate your muscles and you are going to run. But if your motor neurons are not working, you can process that information, but you can’t run. Because of these situations, people with motor neuron diseases can think, but they can’t use their muscles.
If I can “create” new motor neurons with their genetic material and place those new neurons to their body, those people can talk, walk, eat or swim.
But it is very hard because you should place correct parts of the neurons (axons) to other parts of the other neuron (dendrites). It is very hard because each neuron can have 250.000 connections from other neurons.
But I believe that we can reach that technological level in future. I hope we can cure that people in future.