Steve, three of my redstriped ribbon clutch did this. Head cocked at odd angles, convulsing, overreacting to being touched, and belly muscles contracting. The first one, I euthanized right away. The second one, I saw it doing it in the cage, went to go thaw some pinkies and figured I would deal with it when i got back, and when I came back all of them were acting totally normal and I couldn't even figure out which one had been doing it. The third one, I watched for a while and I was astounded when suddenly the snake rolled over onto it's belly and while it seemed rather weak, it had stopped the crazy action. My boyfriend pleaded with me not to put "twitch" as he named it down, and I was rather upset because this was after I had sold all the clutchmates and it was my only male holdback. But that was months ago and ever since those weird incidences I have not witnessed it again. He's almost a foot long now. Not really sure what happened, or what had caused it, possibly something bad in a batch of food?