Now, the fact is that he picks up the other languages quickly because, as they say, speaking one language makes it easier to speak another, but we do know from research that speaking a language can improve brain functions like problem solving, multitasking, and decision making. It could even be said that speaking another language can help you make more rational decisions, but I think I'd leave the door wide open for other people to dispute that, so I won't be going on to that. 