In movies, people can be brainwashed and  given a post-hypnotic suggestion that causes them to respond in a peculiar way when they hear the trigger word.  Sparky has that.

I discovered the word accidentally.  “Crank” isn’t a word that comes up too often.  I verified it late last night, when Sparky was 70% asleep.  He wasn’t eager to get up to go out, so I said “crank”, and he responded just like this.

Here is the slow motion analysis.