I remember a few months ago after a long span of coffee intake with R, we had a hypothesis of eye movement invoking dreaming, rather than dreaming invoking eye moment. I know, it sounded crazy that the relation to eye movement causing REM would have any scientific backing, but we did have a lot of coffee in us. I put that theory and I am sure R did too, into the far reaches of our mind never to come up again, until today.
I recently read something interesting in Dr. Hobson's book "The Dream Drugstore" about eye movement and release of acetylcholine. "In fact, the phasic bursts of acetylcholine (ACh) neuronal discharge appear to be strictly and precisely related to eye movement control by the paramedian reticular formation and the oculomotor system." He continues by saying, "This means that extreme eye movements (as in upward eye rolling and gaze fixation) could produce powerful changes in cholinergic output" (Hobson, 1993, p. 91).
I had read something earlier in the same book where Dr. Hobson described that fixations reduces eye movement and relates to the inability to see something. This means that even when we are looking directly at something, our eyes are slightly moving back and forth in micro movements. This makes it so we can see the object as like radar sees a target.
In conclusion to all of this, it seems that maybe the cause and effect of REM maybe a little backwards. That maybe our eye movement helps support or causes the release of acetylcholine which causes much of our dreams. Regardless as how crazy it sounds, there is some evidence out there that it does in some way support dreaming or disassociation.