The underlying message of the Lancet article is that if you want to understand aggressive behaviour in children look to the social and emotional environment in which they are growing up and the values they bring to the viewing experience.
Faulkner is a writer who has had much to do with my soul but Hemingway is the one who had the most to do with my craft - not simply for his books but for his astounding knowledge of the aspect of craftsmanship in the science of writing.