Yes.
The following dreams are among those that are very common for someone to have during the preactive dying phase.
Dreaming of:
-One’s own death
-Going to heaven
-Being surrounded by angels
-Being reunited with loved ones that have passed on
-Being young again
-Having health and vitality restored (in someone who has been ill for a long period of time)
-Being surrounded by small children they the person does not know. (This isn’t something I’ve ever heard of on a scientific level, but I have witnessed it several times. Other people in the nursing field that I know have also heard of patients having similar dreams.)
Increased frequency of nightmares is also not uncommon. They can include dreaming of:
-Going to hell
-Pain that will not subside (but does not exist when the person is awake)
-Being attacked, or often kicked or punched while trying to sleep
-Being haunted by ghosts or demons
I have worked with hospice for several years, so the majority of the people that I’ve personally witnessed through their last experiences were consciously aware that they were dying. Many of these dreams (as well as the possibility that one might have such dreams) are listed in standard hospice literature that is passed out to loved ones. However, my grandmother was not told that she was going to die, and she expressed having similar experiences shortly before her passing last year. So I don’t think that a person has to be consciously aware that they are dying, I do think in many cases the brain/body does know.
The occurrence of these dreams during sleep, as well as waking hallucinations, is often blamed on the physical changes of the body as it approaches death. A change in blood pressure or breathing can affect the amount of oxygen that the brain receives, which does cause hallucinations and certain physical sensations (like terminal restlessness.) Both are common in the preactive and active dying phases, which may explain why these dreams occur on a purely physical level. Having, perhaps sadly, seen many people through their last days, I have always felt like something much deeper is going on when a person reaches the end of life. I am not a religious or spiritual person, but my experiences almost force me to believe that there is something subconscious that occurs when a person is dying. It is as if you can see something happening on a deeper level within that person, many people fight back very hard at the end.