The best thing about when you speak a foreing language is that you can stop listening what the people are saying.When u listen something in your mother language, at the end, even if you wont to hear in the "background", you know what the people are speaking. at least the discourse in general.
But you cannot unplug. push the "off-botton".
But i think, when u speak another language, you can "say" your brain to stop to traduce what you are listening.
And sometimes it can be VERY VERY HELPFULL!! :)