I was wondering…If someone has been blind since birth, what do they dream? If they have no visual images to draw from how does their subconcious mind make up for this. Do they dream in sound only?
What philosophical value does this question have?
Philosophical value? This post has more philosophical value than literally 1/2 of the stuff I see on this site. Philosophy is very interested in the nature of consciousness, which de facto is the proper realm of psychology and neurobiology; but philosophy likes it all the same.
If blind people dream with visuals, that suggests several things; first, that when one is blind, the brain keeps enough of the occipital lobe dedicated to vision so that “sight” is still neurobiologically possible. Since we know for sure that in blind people large parts of vision centers get appropriated for other purposes (better hearing), this would be interesting. Secondly, that would partially refute the idea that dreaming is “recharging” areas of the brain that have been more significantly used during the day. Third, and perhaps most importantly, there are many components to dreams that are interesting - visuals, occasionally sound and touch. Plot, encoded in logical knowledge (often independent of how we acquire the knowledge - you know something is true without needing justification) and also in emotional awareness (you can have dread in a nightmare that isn’t caused by anything). Because of the disjointed almost atomic nature of dreams, the question of whether or not blind people can dream in visuals can tell us much about to what degree vision is necessarily associated with these other brain functions, and thus to what degree vision is a component of consciousness.
Last, to answer the question - whether or not a blind person dreams in images depends almost 100% on if they have EVER seen. If they were born blind, or went blind before they turned 7, chances are they dream only in concepts and sound, no images. If they went blind after 7, chances are they dream with visuals at least somewhat, if not entirely.
For more info, read this online paper:
Ah, but de jure it is the realm of philosophy, as is all scientific/psychological enquiry.
That is a very interesting report, thanks. It puts thing in a different perspective doesn’t it? Interesting
In order to discover this truth is to ask a blind man himself.
But a greater truth is does a blind, deaf, and mute woman ever dream, such as the intelligent woman Hellen Keller.
or a better yet, a person who is without senses, in this case you can’t ask him anything.
end of my discussion
That is interesting. You might not be able to ask him, but you could put him in an MRI and see what parts of his brain light up when he’s dreaming. Not a perfect answer, but about as good as you’ll get, I think.
On that basis, do cats dream? And if they do dream, then what does that say about consciousness of animals? About consciousness in general?
Cats do dream. And we’ve all heard about “doggie dreams” where a dog will whimper or run in his sleep.
Animals like cats & dogs are unequivocally conscious. Only the more ignorant of abstract philosophers can blindly assert that only humans are conscious.
Now, clearly there’s a level of consciousness that seems to coincide with intelligence. Few people would have a problem with the idea that cats are LESS conscious than humans. But the idea that cats just ACT conscious but are in fact automata, or meat-robots, is ridiculous.
Hi Oldphil,
To answer your question - yes, persons blind since birth dream. Read, for example
psych.ucsc.edu/dreams/Library/hu … 1999a.html
Best,
Michael
I think the real question is whether or not insomaniacs (inability to sleep) dream or not
Wow, this is genuinely great. Thanks.