Note: Sorry this is short and late. I am having computer problems. Encephalon is back – #81 is at http://cepholove.southernfriedscience.com/
Christof Koch has written an article on dreaming for the Scientific American ( here ). It discusses common ‘facts’ about dreaming that have been shown to be in error. This put a different light on the relationship between dreaming and consciousness.
There is not an absolute mapping between REM sleep and dreaming. Non-REM dreams are more static snapshots then narratives in the first person – but not always. Sleepwalking dreams are during non-REM sleep (not too surprising as REM sleep includes a sort of paralysis.
The pons in the brainstem is required for REM sleep but not for dreams. Areas in the temporoparietal-occipital junction in the neocortex are required for dreaming.
Further, we do not smell during dreams, like we see, hear, touch. This fits with our low awareness of smell in consciousness. And there are many more interesting observations in the article, so I recommend reading it.
“they (dreams) bear witness that the brain alone is sufficient to generate consciousness. We dream with eyes shut in the dark, disconnected from the outside world. The brain regions responsible for basic sensory perception are deactivated. Nor is behavior necessary, as we are motionless except for our breathing and eye movements”