What it means to dream
Dreaming is the imagery that occurs in your brain as you sleep. Some psychologists believe dreams occur to help the brain make sense of activities or problems that people may have in their waking lives.
All dreams are unique, often forgettable and a bit difficult to understand — even for experts. That’s part of what makes them so fascinating, for both researchers and the dreamers themselves.
Dreaming is also unique because it uses all five senses — sight, touch, taste, hearing and smell — to tell a story. While dreams can be more image-heavy at times, they involve multiple senses and emotions. The latter is especially true for those who are blind or severely visually impaired.
Do people who are blind have dreams?
Yes, blind people do dream. But the sensory makeup of dreams depends on a person’s past visual experiences. Visual imagery is not always available in dreams for those without sight.
In those who have lost one of the senses (such as sight), the remaining senses are heightened in dreams. This process is called “sensory substitution.”
For example, someone who had sight but lost it later in life can usually still recall images that appear in their dreams. Those who were born with vision loss dream in an entirely different way.
How dreaming can be different for people who are blind
Congenital blindness is blindness that occurs from birth. Acquired blindness is blindness that occurs later in life. Dream content can vary based on life experiences that involve sight and those that don’t.
People who are blind from birth
Experiencing visual elements in dreams is limited for the congenitally blind.
When it comes to visual dreaming, some believe that those who have never been able to see in their waking life cannot see when they dream either. But opposing research shows that people who were born blind are able to actually draw visual elements from their dreams.
This may have to do with the images they assign to descriptions and words that they hear in daily routines.
An important thing to keep in mind is that those who are born blind learn to navigate the world using non-visual senses. Touch, smell, hearing and taste are all essential to understanding their surroundings. They use these non-visual senses to create an accurate 3D map of the world around them. This is called mental imagery or the “mind's eye.”
There’s evidence that this mental imagery is what creates visual impressions in the dreams of congenitally blind people. So when they dream, these non-visual senses are incorporated into the subconscious mind. The senses may even be heightened during the dreaming cycle. This ability can make dreams feel quite vivid, whether visual messages are involved or not.
People who lose their sight later in life
A person who became blind later in life can recount memories from when they could see. And since the brain recalls these events, it’s able to use those memories to play out visual scenarios in dreams.
Research suggests that people who lose their sight later in life see more visual elements in dreams than those who were born blind.
Additionally, individuals who lost their vision during childhood often have fewer visual dreams than those who became blind later. This is because the individual who lost their sight later tends to have more visuals to draw from in their subconscious. (In other words, the older a person is when they lose their vision, the more images they’re able to incorporate from when they could see.)
What do dreams look or feel like without sight?
When you lose one of your senses, such as sight, the remaining senses may feel stronger. This can apply to both waking and sleeping hours. Those with vision loss depend on their senses of smell, hearing and touch to navigate the world around them, whether they’re awake or asleep. This concept is known as neuroplasticity, which involves learning information and applying it to future situations.
Without sight, imagery in dreams can include context from past visual experiences or a heightened version of other senses. But it’s also been observed that blind people experience different types of dreams more often than sighted people. This can include dreams about traveling or moving around. Some also experience a number of nightmares.
What science says about blindness and dreams
The act of dreaming in blind people is studied by numerous researchers. Both sleep patterns and dream content are two important concepts for these studies.
Sleep stages and REM in people who are blind
Sighted people experience several sleep stages. One of these is the rapid eye movement (REM sleep) cycle. During REM, the eyes dart around and there’s an increase in your heart rate. It’s during the REM cycle that a sighted person may have the majority of their vivid dreams.
Multiple studies have found that blind people and sighted people both experience REM cycles. Participants had their eye movements and brainwaves recorded during various sleep studies through electroencephalography (EEG).
However, this research determined that those who are blind don’t have quite as much rapid eye movement. And without a full REM cycle, it’s thought that blind people don’t have as many visually detailed dreams. At least not as many compared to those who have their sight.
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Research findings on dream content
Do blind people dream the same way as sighted people?
Unlike blind people, sighted people may have several vivid, visual dreams every night. Blind people tend to dream more broadly, incorporating travel and movements into their dreams. Both blind and sighted people can dream about human interactions and have emotion in their dreams.
Blind people may also observe floating spots, rather than detailed objects in their dreams. Certain floating spots can also be representative of other senses. A traveling sound, such as a dog that is running and barking may be represented by a traveling, floating spot.
How does a blind person know when they’re awake?
Everyone has something called a circadian rhythm. A circadian rhythm indicates to your body when it’s time to go to sleep and time to wake up. Things such as light and darkness help cue the body for sleep and wakefulness.
Blind people also experience circadian rhythms. And many blind people are able to sense light around them, despite not being able to see it directly.
Why understanding these dreams matters
The research following these dream cycles helps researchers understand visual processing in people without sight. It can also explain how blind people use both memories and other senses to subconsciously process information.
Although dreaming is different for those with vision loss or blindness, their dreams are no less vivid or meaningful than dreams of sighted people. Not only is the concept of blind dreaming fascinating to learn about, it’s also important for building empathy toward people with sensory diversity.
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