> One thinks in words
No. There are people who believe they think in words, because they haven't bothered to examine the question, but there are no people who think in words.
Think about the number of people you've ever seen do a double take at the idea that "I don't know how to put this into words".
From that perspective, the experience of thinking in words or pictures is distinct from actually thinking in words or pictures. Saying one thinks in one of these ways seems to be saying what they identify thinking with.
For example, I don't usually think of fantasy as thinking. If I day dream, I wouldn't say I am thinking, but that is fairly visual. To what degree am I saying something about myself vs my identity if I say I do or don't think in words given that context?
Relatedly, I've noticed that when it comes to remembering something, it is not 'I' that remember. Rather 'I' set up mental cues and direct focus, which then hopefully causes the memory to be placed within my awareness. This happens below the level of direct experience. But I might say I failed to remember, taking responsibility for something that 'I' - the part separated from the automatic functions of the body - did not do.
So I'm suggesting statements about words vs pictures are about ego, metaphor and meaning-building, and not about actual mechanisms or communicating actual differences in the experience of thinking.
It can be difficult to talk about these things because such conversations implicitly occur between our identities, not between who we actually are - something beyond our grasp - and the noise this introduces is something I don't know how to surmount, or if it can be surmounted.