The idea of plasticity and that the brain contains stored symphonies is intriguing. Perhaps these phenomena at work can be seen in stroke victims. Does damage to a certain part of the brain effect motor symphonies and CPG? However, we do know that the brain has more than one way of doing one thing. In stroke victims or people who have damage to their brain because of disease or disorders, it would probably be interesting to see how the brain re-networks itself and accomodates to an injury that will effect motor output.

In a cat, where all input pathways are cut(optic, olfactory, dorsal roots, and connection between spinal cord and the brain), communication to the outside world was disturbed. Even so, the experiment showed that motor patterns existed and walking was possible to the cat. How is it that a human who has his spinal cord severed cannot walk? If one must tell the CPG if one wants to walk, doesn't that indicate an internal input system must exist and that cutting the spinal cord will result the person's inability to tell his spinal cord to walk?

Yep, humans lack ability of the rostral part of the nervous system to activate walking CPG's, located in the spinal cord. And yes, stroke both may damage CPG's and are interesting in terms of the "multiple ways to do same thing (more or less) idea", which provides some optimism for recovery. PG