Didn't you just ask that? I coulda swore....
It was just like déjà vu all over again!
Quite unexplainable,to be honest.
some studies show it is actually a very slight delayed recognition that something happened, so when you do become "consciously aware" then it seems like it already happened, because it did.
A feeling of like you have been here before.
one theory is that sometimes the neurons in our brain misfire, so the information about what you are experiencing actually makes it into the memory section of your brain BEFORE it registers in the this-is-happening-now part of your brain.
but that is just one theory.