The words mean nothing. It'd be better to look into where the kids were exposed to the words, or if they were exposed in a controlled test, what associations they had already formed around the words. Just saying fuck won't make someone violent. If they associate it with a 'feeling' of aggression, then yeah, it probably could snap them into that mindset.
But I still think this kind of thing is missing the point. Mankind has always been exposed to instincts, aggressive emotions, and so on. The solution isn't to wipe out all potential triggers 'for our own safety' but to teach people to control themselves. You know, like how killing your father to seize control of the family isn't really the thing to do any more. Perhaps it would be better to ban fathers, so nobody would be tempted to kill them...