The following is just a copy-paste of my description elsewhere of this 2008 paper from Christopher L. Heavey and Russell T. Hurlburt.

I just ran across a 2008 paper, ‘The phenomena of inner experience’ (https://hurlburt.faculty.unlv.edu/heavey-hurlburt-2008.pdf), that tries to taxonomize the common types of mental experience. They asked about 16 different phenomena; 11 of them were present in <= 3% of experience reports, so they focused on the other 5, which were all present in >= 22% of reports. Those are: inner speech, inner seeing, unsymbolized thinking, feeling, and sensory awareness. They found people varied very widely on which ones they had, and how often. See screenshots for a) a summary of the five phenomena, and b) the relative commonness of the different ones, along with the the highest level reported by any participant (eg the most visual participant had inner seeing in 90% of their reports) and lowest level (which is 0% in all categories). Interesting stuff IMHO!

For me personally, using their categories, I would say the large majority are ‘unsymbolized thinking’, and occasionally inner speech or feeling or sensory awareness, inner seeing never. I’d be curious to hear other people’s splits.

As I said at CL, for me a lot of it is kinesthetic, a sense of spatial relationships between concepts relative to my body, and a lot of it is…algebraic, almost? It’s about the relationships between concepts. And sometimes it’s really nothing verbalizable at all, like it’s not uncommon if someone asks me what I’m thinking to be like ‘uhhhhhh…’

The less verbalizable parts are maybe almost like sensory awareness, except that instead of awareness of something I’m seeing or hearing, it’s awareness of one or more concept-thingies.

A few excerpts:

‘Most participants had one form of inner experience predominate; 22 of the 30 participants had at least one of the five common phenomena occurring in 50% or more of their samples.’

‘The most common dominant phenomenon was inner seeing, followed by feelings, and then inner speech.’

‘The phenomenon of sensory awareness requires additional explanation to ensure that it is comprehended. Sensory awareness, as we define it, is the experience of being drawn to and the paying particular, thematic attention to some sensory quality of the inner or outer environment. Sensory awareness is not merely the perception of some object; it is the direct attention to some particular sensory quality of the object. Thus Sally is reaching for a can of Coke with the intention of taking a drink. She is perceptually aware of the can as she reaches toward it, and could, if asked, report its shape, color, and so on. That does not count as sensory awareness by our definition. By contrast, Maria is also reaching for a can of Coke with the intention of taking a drink. As she reaches, she notices how the light reflects off the shoulder of the can, notices the can’s slightly rosy redness below the shoulder and its deeper redness above. Maria does have a sensory awareness as we define it.’

Although their whole idea is to take an open-ended phenomenological approach without presuppositions, the following quote makes me a bit suspicious that the experimenters’ iterative feedback may be inadvertently guiding participants into certain categories:

‘training should be “iterative”: participants should make attempts at observing/describing their own phenomena, receive feedback on those attempts, then make new observing/describing attempts, followed by new feedback, and so on. For example, DES shows repeatedly that many, if not most, people who have unsymbolized thinking (the experience of thinking without words or other symbols) will at first report such thinking to be in words. Only after repeated training as they iteratively confront the apprehension of their own experience do they come to recognize their presupposition of words as being false.’

Also for the record, their full list of 16 (given in an earlier paper) is ‘inner speech, partially worded speech, unworded speech, worded thinking, image, imageless seeing, unsymbolized thinking, inner hearing, feeling, sensory awareness, just doing, just talking, just listening, just reading, just watching TV, and multiple awareness.’