I doubt the cat's skull is opened given the situation. It would be more sterile than that if it were.
http://www.youtube.com/watch?v=FLb9EIiSyG8
EDIT:
Do cats have some sort of consicousness?
Recognizing "familiar"/"frinend" cats from "strangers" requires further image analysis, information processing, and, as a result, changing of cat's behaviour. This require conscious processes, IMO. Or not?
But, on the other hand, if cats have consciousness and able to recognize different cats, why they aren't self-aware?
I doubt the cat's skull is opened given the situation. It would be more sterile than that if it were.
