Can't you see she's laughing WITH her father?? She's remembering how she used to tease her mother. She's RESPONDING! That proves she WAS NOT brain dead or in a coma. Did you forget that she's brain-damaged, and won't respond like you or me? That's how they laugh. In case you're not familiar with how brain-damaged people are, THIS is a disabled person RESPONDING. HOW can you say it's bunk??? Please watch it again, very carefully, unless you just don't care or have no interest. If so, there's no reason to respond to you any longer.
I did watch it -- she is "responding" as an animal does. Yes, there is some response to stimulus, but it is not a reasoned response.
Like I said, non-scientific and lacking rigor. If she was "responding" to what was she responding? You might note his voice gets higher and louder then she kicks in.
This doesn't even pass any smell test.