Today I found out how the completely blind dream.

It turns out that if they went completely blind before around the age of 5-7 years old, they will typically dream without any visual experiences. In the very few cases where some report having visual experiences in their dreams, these experiences are more in the abstract sense where they feel like they were seeing something, even though they couldn’t actually recollect or describe when they woke up what the thing looked liked that they saw. This is similar to how occasionally in dreams you can just “know” something, even though there is nothing specifically that you are experiencing in the dream which should indicate what you know. For instance, in a dream where when you wake up, you remember feeling like you were in danger in the dream, even though nothing you can recall in the dream indicated any danger. There was just some abstract sense of it.

Outside of the interesting “around the age of 5-7” cutoff for visual dream experiences, the dreams of those who are completely blind before this age tend to be principally auditory in nature. However, what is also fascinating is that, compared to those who can see and hear, the blind report drastically increased taste/smell/touch sensations in their dreams, not just auditory sensations taking over for the lack of visual sensations.

Now if they go completely blind after around the age of 5-7, the vast majority of completely blind people will at first dream very similar dreams to those who are not blind, albeit, once again, with more non-visual sensory experiences than is reported by those who can see and hear. But nevertheless, their visual experiences in their dreams tend to be quite similar to those who can see. If they had diminished vision early on in life though, perhaps only seeing colors, then their visual experiences in their dreams tend to be similarly diminished based on those visual experiences. As time passes, they typically will report more and more prevalence of experiences from the other senses and less and less visual experiences in dreams. Often the visual experiences will become more vague and “blurry” as time passes, but they do seem to remain to some extent throughout the blind person’s entire life.

Bonus Facts:

Rapid eye movements (REMs) during sleep occur very mildly and often not at all in people blinded before around the age of five to seven.

Before her teacher first came to her, Helen Keller, in her autobiography, stated that her dreams were devoid of any kind of sound/sight/thought/etc. and only contained fear and strong abstract sensations. She states, “My dreams have strangely changed during the past twelve years. Before and after my teacher first came to me, they were devoid of sound, of thought or emotion of any kind, except fear, and only came in the form of sensations. I would often dream that I ran into a still, dark room, and that, while I stood there, I felt something fall heavily without any noise, causing the floor to shake up and down violently; and each time I woke up with a jump. As I learned more and more about the objects around me, this strange dream ceased to haunt me; but I was in a high state of excitement and received impressions very easily. It is not strange then that I dreamed at the time of a wolf, which seemed to rush towards me and put his cruel teeth deep into my body! I could not speak (the fact was, I could only spell with my fingers), and I tried to scream; but no sound escaped from my lips. It is very likely that I had heard the story of Red Riding Hood, and was deeply impressed by it. This dream, however, passed away in time, and I began to dream of objects outside myself.”

Deaf people experience a parallel effect in their dreams as blind people. Those who’ve been deaf from early childhood don’t hear sounds in their dreams and people talking in their dreams do so in sign language. Their dreams have also been shown to be much more vivid in terms of imagery and colors than people who can hear and see.

People who lucidly dream are called “oneironauts”. This is from the Greek “Oneirology” meaning “the study of dreams”.

During sleep, with your eyes being closed, all sensory signals except the sense of smell end up passing through your thalamus. During your sleep cycle, the brain suppresses thalamic activity and thus principally only processes signals from itself. Long story short, some researchers believe that this suppressed input and output creates neural oscillations, which may be the source of dreams.

Another theory, suggested by Eugen Tarnow, is that dreams are simply excitations of long-term memories, but without the normal executive brain function that interprets long term memory through a “reality check” sort of filter. This is somewhat based on researchers Penfield and Rasmussen’s study showing that stimulating the cortex with electrical pulses will produce a waking dream-like experience.

Many researchers believe that dreaming is part of some sort of mechanism for setting the day’s activities more firmly in long term memory, although the mechanism for how this is actually taking place is somewhat of a mystery. However, a 2001 study seems to have shed some light on what might be happening here. According to this study, during REM sleep, higher levels of the stress hormone cortisol cause decreased activity between the hippocampus and neocortex. These researchers theorize that, similar to what happens when some memory is created when one is experiencing something in the waking world under stress, once memories are linked with similar memories during sleep, the stress hormone that shows up during REM sleep works to firmly set the links and memory in place.

Blind people obviously have a very different sense of how they find something “pretty” or “ugly”. In doing research for this article, it was interesting to note that several blind people I read about found things “pretty” or not based on how smooth the object was, with the more smooth something is the more pretty it is. I’m curious from any blind readers of this article if you also find things pretty or ugly based on smoothness and if this is as common as it seemed from my readings?

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