Dementia Dreams

I don't want to seem insensitive and I certainly don't wish to upset anyone, but I'm wondering whether people with dementia and Alzeimers have normal dreams.
The mind is separate from the body so, when we're asleep, does it operate normally or does it continue to be under the influence of the body.
During the day, we are in control of our movements but during sleep, the body moves around of its own accord. How many of us wake up to find the covers have been kicked off or even that we have fallen out of bed.
Heavy stuff but intriguing.