I came across this article yesterday and it was a massive relief (I've been trying to find a way to explain this for this thread and really struggled!)
It describes the inside of my head best – I'd say I have 90% unsymbolised or 'Feature 5' thinking, only interrupted by verbal thinking when I'm 'rehearsing' something I'm going to say.
Well worth reading the whole thing (it's not too long) to get the whole picture, but a brief excerpt:
I've been saying that this procedure reveals five frequently occurring phenomena of everyday inner experience: inner speech, inner seeing, feelings, sensory awareness, and "Feature 5." I haven't said what Feature 5 is, giving you the opportunity to commit yourself to your speculation. Now I'll describe it: unsymbolized thinking.
Unsymbolized thinking is the experience of an explicit, differentiated thought that does not include the experience of words, images, or any other symbols. For example, if you had been beeped a moment ago, you might have experienced an unsymbolized thought which, if expressed in words, might have been something like "I wonder what Feature 5 is." But if this was an unsymbolized thought, there would have been no experienced words—no experience of the word "wonder" or of "Feature 5." There would have been no experienced images—no seeing of a beeper or of anything else. There would have been no experienced symbols of any kind, and yet you would have directly apprehended ("before the footlights of your consciousness") yourself as thinking that exact thought.