So we've learned that corollary discharge is responsible for a certain type of neuron communication. It signals when to fire and provides feedback about which neurons have fired and when. It may explain how a message travelling towards more than one other neuron is only passed on by one neuron. That neuron signals, through corollary discharge, that the others don't need to fire because it has. I wonder now if corollary discharge has something to do with willpower or inhibition and subtle movements.

There could be some neural activity that is increasing the likelihood that the person will engage in a behavior, say, eating. If this behavior is a motor symphony, it is possible that the activity that we interpret as desire is regulated by not just a single pathway but a whole network. Perhaps corollary discharge signals from one neuron to others prevents the desire from being too strong by inhibiting some neurons farther in the pathway. This could prevent the eating behavior. Corollary discharge, in a similar way, may be responsible for inhibition of say overtly displaying sexual desires.

Most interesting is how corollary discharge signals may function in subtle movements. Just as good and rapid piano playing supports the idea of a central pattern generator, soft piano playing supports corollary discharge. To be able to press a key with the precisely desired force at a very specific pace is very difficult. I would imagine that as the finger approaches the key there is constant regulation of the speed and force with which it nears the key. There must be corollary discharge signals that let one neuron know that, say, too many others fired and the finger is approaching too rapidly so the anchor(last) neuron must compensate by perhaps not firing at all. If good piano playing requires a high quality of motor symphony and thus a specific central pattern generator, and if such playing must be learned, is it that CPG isn't present from birth and develops as we "learn". It's not genetic but I still don't know if its potential to bring on motor symphony is there from birthand "learning" means turning off that which inhibits the CPG or if CPG itself, from the beginning, can affect behavior but only once sufficient corollary discharge signals have developed("learning"). So is "learning" the rise of the CPG or the rise of CD to coordinate the CPG?

Probably both ... and some other things as well (remember the nervous system does anything at least six different ways?). You've got some interesting and very subtle ideas out of our CD discussion. Simple CD signals tend to coordinate activity in groups of neurons, but yes indeed it is possible that similar signals may help to adjust and compensate even CPG patterns as they are being played out. And yes, of course, they may help to explain regulation ("inhibition") of various motivational states. PG