The harder I'm thinking, the less sense my inner monologue seems to make. Even for fairly simple things -- other than reading -- it tends to be a jumble of half-articulated sentence fragments and images. When I'm thinking hard, there tend to be significant portions that I have no idea what to call them.

So the inner monologue clearly isn't how I think (what I use to think), but seems to be something more like samples from a debug trace or audit log.