A person who's born blind can not see visuals in their dreams as they can't draw from that sense... I could go into a whole medical discussion about it but I can't remember the terms and such and am far too lazy.
Though, they can still dream via other senses such as sound and touch. There simply wouldn't be any visuals.
A dream with no visuals actually sounds pretty awesome...
It makes me wonder how it would feel to 'hear' or 'feel' something's spatial dimensions constantly and consistently.
How it would be to grow up blind/sans sight, and identify people by sound, scent or touch alone (ofc all 3 can be used together).
How does a person 'appear' to someone who is blind? Is it much more deep, and intricate (Personalities noted by vocals, physical contact [such as shaking hands etc, provided they do])?
Due to utilizing the other senses and ultimately heightening them throughout life (even by a little bit), is it easy to tell when someone is lying?
How does math work in one's mind that has never seen numbers/values? Is this remedied by using the repetition of sound to encourage one to notice the sudden difference/frequency of sounds received? Or by a number of different objects placed in one's hands? Different smells?
How does one without sight imagine Space? How would they react to hearing radio waves being emitted by other planets?
Better yet, how does the world work for a person born without hearing, 100%?
I think I'd actually like being totally deaf sometimes. If a picture is a thousand words, and you have almost or no concept of words or phonics without extensive speech therapy...
Then besides the alienation, the whole world is just
one awesome sunset. Or
Sunflower. Or
Rainbow. Or, giant laser piercing the moon and shattering it into asteroid-sized bits.
Oh man, imagine being a Pentachromat with total deafness.