Favorite Answer:It depends. Did he hear the words but just get confused because of all the extra input (did not understand despite hearing the words because his brain was working on too many things at once) or did he simply find it impossible to even know what was being said, because the extra noise obscured the words?
The funny thing about language is that different words have different meanings, and we choose each word with the idea of making the meaning as we want it to be, rather than just shoving in words and hoping it means what we want to mean.
You may say either, but they do not mean the same things in detail.