i dream in vivid colors, noting textures & hues, smells, tastes, sensations . . . it’s the next best thing to being there. discussions w/ others made me realize not all others do, i.e…, some are in black & white, murky, blurry, etc. why the disparity in human dreaming?
I doubt you’ll get an actual-factual answer to this.
Sleep and dreaming are two of the more mysterious parts of human psychology / physiology.
My own two cents is that maybe people who claim to dream in black and white are mistaken.
The thing with dreams is that they aren’t retained very well on waking.
I’ve had times where I’ve woken up, thought about what an incredible dream I just had, then as I try to step through the dream in my mind I find I have instantly completely forgotten the dream!
The point is, even though I don’t doubt that I dream in colour, I can only remember a handful of times where colour was significant in the dream and therefore I’m sure I saw in colour. All other times my memory is so vague that I couldn’t tell you much about the colours.
Someone who’d never experienced a dream where colour was significant could easily convince themself that they’ve never seen colours in dreams.
Still, it’s true that the vividness of dreams varies, and I’d be quite interested to know just how vivid your dreams are.
Personally, I’ve experienced touch, smell and pain on only a handful of occasions. I’ve never tasted anything.
I have heightened emotions in dreams, but I think that’s pretty common.
My most vivid dreams tend to be lucid, where I’ve had dreams where, say, I’ve picked up a newspaper and read from it (the text of the articles was grammatically correct, but they jumped around subjects and didn’t make any sense in their entirety).
Thanks for reading, sorry for the long post 
I’m sure that others with more knowledge on the conscious and unconscious would provide more information…but I suspect it’s because people THINK differently.
We all experience things in a different way - for example taste. I hate eggs. Some people love eggs. Touch - my friend is physically repulsed by tin foil. I am indifferent towards tin foil.
Same goes for all other senses; how we experience what we see, hear, feel, smell and taste varies from person to person. In our waking life, we have choices; when we are asleep, we do not.
thanks for offering your thoughts. this came up recently in a conversation w/ my best friend since childhood. we were having a rather pointless discussion re a park we played in as kids in the '70s. i said something about stone benches behind the amphitheatre, she had no memory of benches. i knew they were there & said so. we dropped it.
that night, i dreamed about the park, the amphitheatre, the damned stone benches. i could see the different colored stones, felt their rough texture, the cement edges holding them together. it was like i was sittiing on them 30 yrs ago in my dream.
when my friend & i spoke again, i asked her to humor me & to visit the park & check about the benches. (she & her husband live 3 hrs away but drive down once a month to take her mom to Mass). they did, & while they were no longer standing, their stone supports were still there.
that dream was so real to me that i started asking others about their dreams. few seemed as vivid, but some reportedly were. the writer poppy z brite posts her dreams in her online blog & hers are exceptionally technicolor. i began wondering if creativity affects perception, or if it enhances it.
i have, in my dreams, danced & floated above the ground, flown high above the treetops, made out w/ mick jagger & bruce springsten (not at the same time), met JFK, been battered by waves, had (good) sex, felt myself being tortured, made and eaten lasagna, & once even gotten high off cocaine, which i’ve been told is unheard of. i’d like to study this further, but as you said, it’s largely mysterious territory.
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I hate this kind of dream. It seems weird that dream pain hurts, but it really does. What’s even worse is when I have any kind of pain or even discomfort in real life and I fall asleep; I incorporate the real pain it into my dream and the pain hurts a lot worse in the dream than it does in reality. When the edge of my bed was pressing into my shin one time, I dreamed that a guy was torturing me by slicing into my leg over and over with a red-hot knife. When I woke up, it was only a mild ache, but man, in that dream, it really felt like my leg was being sliced open, over and over. Perhaps some inhibitory systems that function when you’re completely conscious don’t work while you’re dreaming, or something.
I have different dreams if I’m unwell; if I’m on my back; if I get interrupted midway through; if I hear sounds in the real world; if I am in a new bed; if I am hungry.
Science doesn’t understand dreams, so it’s a guarantee that I sure don’t.
real world sounds often get incorporated into my dreams. the lawn guy’s weedeater becoes a plane’s rumble, hard rain a flood (i lived thru katrina).
the coolest thing about dreaming is that sometimes i can program my (1st) dream. i lie in bed & think about what i’d like to dream and at some point the thoughts segue into dreams. this has also allowed me to return to an interrupted dream.
when i have fever, my dreams are so strange! i often talk in fever dreams, and i’m told i carry on detailed, if nonsensical, conversations.
and then here are those dreams where you’re like, “it’s ok, it’s just a dream.” why do you someties know it’s a dream, but others think its real?
maybe i just dream too much . . . 
Heh, yeah, this happens to me all the time. One time, very early in the morning, I was having a fairly boring dream about walking through my house when somebody in the bathroom slammed a cabinet shut. In my dream, the sound suddenly became a violent explosion – I rushed to the window and looked out, just as chunks of debris and pieces of corpses began to rain from the sky. The front lawn was strewn with arms and legs. :eek:
I woke shortly thereafter, and somehow I remembered the sound more clearly then, which is how I knew it was the cabinet door slamming to, and not an actual explosion. 
I have a health problem that causes a lot of sleep disruption. However, I’m on a medication that is gradually helping me to heal. For me, at least, the better my sleep becomes, the less vivid my dreams are, and the less I remember them. So maybe some of the differences in how people dream have to do with differences in how well we sleep.
When my health problems were more out of control, I had vivid, complex dreams almost every night, and I could remember them. I’ve experienced all five senses in dreams, and dreamed about a lot of cool things like flying, touching dolphins and whales, etc. My favorite dream was about three years ago when I became a peregrine and flew around for a while. I only woke up when I dove and miscalculated my trajectory, so rather than swooping back up, I was forced to land on the ground.
I’ve had dreams I was falling and would wake up when I smacked into the ground. Dreams I was murdered. I even had a dream in which I passed out and came to–while still in the dream. I’ve had lucid dreams where I realized I was dreaming and could stay in the dream, controlling the action.
Now that I sleep more soundly, I still have occasional dreams like these, but not nearly as often. I miss them, but I’m much happier being healthier. It’s worth the tradeoff.