Ever had a Déjà vu?

There are situations when you are 100% sure that you saw or heard or felt something before, even though you have no clue of where and when.

Or, you are trying to remember something that you know very well, but just can't. A word or a name is on the tip of your tongue but you just can't get it out. Neither can those around you. Only after a while, when thinking about something else, you can remember it.

Why is that happening? What's the explanation? What is going on in your brain in that moment? Watch the video below to find your answers.