Chapter Six of my book in draft (working title Perplexities of Consciousness) is available here. As with the other chapters, I've tried to make it comprehensible without having read the previous chapters. Also as with the other chapters, I would very much value feedback, either by email or as comments on this post.
Do we have a constant, complex flow of conscious experience in many sensory modalities simultaneously? Or is experience limited to one or a few modalities, regions, or objects at a time? Philosophers and psychologists disagree, running the spectrum from saying that experience is radically sparse (e.g., Julian Jaynes) to saying it's radically abundant (e.g., William James). Existing introspective and empirical arguments (including arguments from "inattentional blindness") generally beg the question. I describe the results of an experiment in which I gave subjects beepers to wear during everyday activity. When a beep sounded, they were to note the last conscious experience they were having immediately before the beep. I asked some participants to report any experience they could remember. I asked others to report simply whether they had visual experience or not. Still others I asked if they had tactile experience or not, or visual experience in the far right visual field, or tactile experience in the left foot. Interpreted at face value, the data suggest a moderate view according to which experience broadly outruns attentional focus but does not occur anything like 100% of the time through the whole field of each sensory modality. However, I offer a number of reasons not to take the reports at face value. I suggest that the issue may, in fact, prove utterly intractable. And if so, it may prove impossible to reach justifiable scientific consensus on a theory of consciousness.