I appreciate you're not giving your dreams too much credence, and I'd agree that if it seems like there's a conscious person in your dreams, it's closer to the activation of a memory of how people are, rather than an actual person living in your head.
In fact, I've often wondered if we're conscious at all when we sleep. We wake up with all these memories of having experienced things, but that's not the same as having actually experienced things. You can have false memories, which means you can remember experiencing things you didn't. It may be the case that (unless you're lucid dreaming), you're not really conscious at all while dreaming. In which case your weirdest experience really wasn't.
Clearly some parts of your mind are switched off when you sleep. Your reasoning faculties aren't working correctly, which is why you can be unsure whether or not you're dreaming, but know with near certainty that you're awake. Maybe the parts of the mind involved in consciousness are off as well?
On the other hand, I often wonder what people having a seizure experience. Opposite to people dreaming, they often report experiencing nothing. But is this true? Or do they just not remember?
Over a decade ago, I dreamed that I was a high school student attending a swim meet. After I won my race, my coach informed me that I was in a dream, but I didn’t believe her and insisted we were in the real world. I could remember my entire life in the dream world, I had no memories of my true life, and I was able to examine my surroundings in fine detail. I spent some time arguing with my coach, but I eventually opened my eyes and returned to reality- shaken, and left with a sense of loss for the dream life I’d left behind. The experience was intense enough to make me question two things; one was the nature of reality, and the other was whether other conscious entities inhabit our minds, separate from the “I” that communicates with the outside world. I wrote about the experience in more detail here.
I shouldn’t have been surprised to see my post shared on paranormal forums. My unsettling dream is not the weirdest thing I’ve ever shared or discussed online- that honor would go to my attempts to contact time travelers. However, unlike my time-travel experiments, I never gave any grounding explanation for my dream.
Though my dream was strange, it was not a truly novel experience. There was no evidence of another conscious entity in my mind beyond the evidence my brain gives me on a regular basis- evidence we all experience regularly and don’t seem to find very unusual.
To demonstrate, I will examine the behavior of the dream character, Coach Catherine. In the dream, Catherine defied expectations by breaking out of her role in the dream; she went from hostile swim coach to gentle truthteller. This was surprising, but dream characters often act in unexpected ways that break them out of their previous roles. In nightmares, characters whom you previously trusted can suddenly turn against you in bizarre and frightening ways. The nightmare would not be as frightening if the character did not act unexpectedly. Yet people rarely come out of these nightmares questioning whether there is a sentient and hostile consciousness lurking in their mind.
The hyperassociative nature of dreaming may be one explanation for why characters break out of roles- their behaviors are haphazardly put-together fragments of memories and emotions. Since the dorsolateral prefrontal cortex (dlPFC)deactivates during sleep, these fragments are not put together in logical ways, so inconsistent behavior should not be unexpected.
Catherine presented me with a truth that I did not believe- that I was dreaming, and that my real self lived in a different reality. I rejected this knowledge, even though it was correct, until I tested her claim and awoke. But though it may seem strange that a character in a dream should know something that I did not, I have had similar experiences in my waking life. I’ve often questioned memories that surfaced in my mind- with good reason. Memory is notoriously unreliable. There have been many times when I’ve remembered things and said to myself “wait- that can’t be right.” Sometimes these memories proved to be correct, and at sometimes not, but each time, my memory was supplying me with something my conscious mind rejected, similar to my dream. The way the subconscious mind supplies memories does not necessarily indicate the activity of a separate entity within our minds. That claim may be researched further, but my dream does not offer any special evidence.
Even though I downplayed the experience of having lived another life within my dream, I was affected a great deal. I mourned the life in my dream, and to this day, I often question and test my reality. People who read my original post seem to find the alternate reality the most fascinating aspect my story. My dream has been compared to another infamous internet tale about a person who lived an entire lifetime in their dream, only to be brought back to reality by a strange fixation on a lamp. I think the main difference between the lamp story and mine is that the lamp dream is presented in a linear fashion- the original poster met the girl, wooed her, married her, had kids, and then found the disturbing lamp that ultimately brought him back. My dream, however, started in the middle- the day of the swim meet- and it was only when Coach Catherine forced me to question my reality that I conjured memories of my life at will. Gwern explained this section of my dream very well, and I am not surprised that my mind could summon new memories to fit with the story it has already created. I cannot speak for the poster in the lamp story, but if their story is true and they lived their dream in such a linear fashion, it is possible that their mind passed over a great many details that would have made the lifetime they experienced much longer than the time they were unconscious.
The dream I experienced was vivid and detailed to the point it seemed real, but I am particularly prone to vivid dreams. My favorite vivid dream is the one where I look into the sky and my eyes become powerful telescopes, allowing me to view distant planets in sparkling detail at will. Many people have reported having very vivid dreams, and while it can be unsettling to find yourself back in reality after such a dream, there’s no reason to believe the vividness of your dream is anything beyond the effect of stress, medication, or simply the ability to visualize very well.
Even though this was the most vivid and unsettling dream I’ve ever had, when I look at each component, I can only conclude that my brain was not doing anything novel that cannot be explained beyond our current models of the human mind and the dreams minds conjure. If there are other conscious entities in our minds, my dream was not the key to finding or dismissing them. If there are alternate realities, my dream is not the key to accessing them. My weirdest experience wasn’t that weird, after all.