We've determined that corollary discharge is responsible for virtually every movement from co ordinated, complex mostions to (ugghhh! i don't want to use it, but i'm going to dare to) "reflexes". No behavior can exist without some pattern of activity, and hence, without a CD. CD's are the determining factor in output considering that they can overrule input and they can exist without input. The scary thing is that they are located outside the I-function which supposes that CD's can trigger behavior regardless of what you choose to do.

I'm beginning to think of CD's as a god--they have supreme rule over the nervous system. I use this idea for explaining the phantom limb phenomena. People with phantom limbs might choose to move their non-existent arm in order to get through a door way, but CD's don't coincide with this choice, so they body senses that the arm is still in danger of hitting the door frame. Possibly, the proprioceptors in the phantom limb are not receiving the information that signals the absence of a limb so they still feed input into the CD circuit which tells the body that the limb is present and needs to be moved. The CD takes action and the pattern it generates continues, but since there is no limb to be moved, the proproiceptors do not detect the change in limb position that normally would occur. CD's have control over the phantom limb but because the output doesn't reach the limb (since it isn't there), the CD generates continuously. I am a little confused about how CD's relate to cloning. I find the topic of cloning extremely interesting, but I am not sure where CD's fit into all of this. Are CD's genetically determined? And how, if there are billions of neurons in a cloned body, could CD's not exist? I don't think of CD's as an addition to the basic nervous system, I tend to think of them as simply a result of the nervous system: if you have a network of nerves, then inevitably, CD's are present. If I take that spporach, then CD's don't pose problems for cloning--a scientist creates a pattern of nerves, then he creates CD's as well.

What would be amazing/ fascinating and TERRIFYING would be when scientists do indeed clone and then they can begin to program their own CD's such that they can ellicit certain behaviors. Of course, it would be impossible to completely replicate all behavior since no circuits are identical, but similar human behaviors might be able to be manipulated from a cloned "body".

i'm not quite sure whether to fear or look forward to the day.........

Glad you like CD's (so do I, obviously), but don't get TOO carried away. As you say, they are "simply a result of the nervous system". And, hence, as you say, they bear the same relation to cloning as any other aspect of the nervous system (and, like any other aspect, they move emerge from genetic information, from experience, and most typically from both). As for clones, remember that there are different kinds. The recent news reports have to do with making embryos which are genetically identical to donor adults. By the time those grow up, they are likely to be no more like the donor than identical twins are like each other. As for the possible of make people who BEHAVE identically, using ANY technique, that's unbelievably unlikely, for reasons we'll get to as we go on (and are nicely described in an article by George Johnson "Don't Worry. A Brain Can't be Cloned" in the New York Times Week in Review, Sunday, 2 March, 1997). PG