I searched this site for articles about hyperesthesia, and found out some good information.
My cat, Buddy, who also has cerebellar hypoplasia, has some odd things going on. I think it might be hyperesthesia, but with just not all the same symptoms.
Besides the CH, which makes him clumsy, he walks like he's drunk, falls over alot, etc........he began biting his tail. He would look at it like it was a mortal enemy, then bite it and hiss and growl because he was hurting himself. I don't notice the twitching of his skin....occasionally, but not to extreme I don't think. He also goes into a rage where you just can't calm him down. He'll start chasing the other cats around and scare the living daylights out of them. If he catches them (which he doesn't very often because of the CH) he really does beat up on them. It's an all-out, fur flying fight. It's like he just can't help it. He will also lash out at me sometimes for no reason. A bite (doesn't break the skin)--or a scratch when he should be very relaxed. Sometimes when he is sleeping with me, I'll reach over just to pet him and he'll hiss or growl at me.
He has since been put on Prozac and is doing "somewhat" better. Does this sound like hyperesthesia to you??
It takes a very strong person to manage a feral cat colony. I'm am weakening.