I found the revelation that people don't do this fascinating. I guess I assumed it was part of the human experience.

I had a conversation with a buddy of mine about what language he thinks in one time, due to English being a seconds language for him and it is funny because looking back on that conversation we both assumed that internal monologue was just a default.

I did notice a pattern in the minority of people that do not internal monologue, where overwhelmingly populated by females.