Our nighttime fantasies are one of the many quirks of the brain that continue to confuse scientists, but there is one question that frequently turns up in both online question boards and scientific studies: How do blind people experience dreams?

A paper published in Sleep Medicine back in 2014 looked into the “sensory construction of dreams” among blind people to try and pry into this question. Neuroscientists from the University of Copenhagen gathered 25 blind people, 11 who were blind from birth and 14 who became blind after age 1, along with 25 sighted participants. Over the course of four weeks, they interviewed the participants about their dreams and asked them to fill out a structured dream diary when they woke up each day.

The dream diary asked all kinds of questions that you’re probably curious about yourself: What form do they take? What do they see in their dreams? Do they experience nightmares?

The study found that the blind participants reported a far richer and wider variety of senses in their dreams compared to the non-blind participants. By a considerable margin, they experienced far more vivid sensations of sound, touch, taste, and smell. The sighted people tended to just remember the visual sensation of the dream.

Those who had acquired blindness later in life – and therefore had experienced some vision – did report some visual dreams. The study noted many of these people “described an object or a scene verbally in such rich visual terms that the interlocutor began to doubt if these individuals really lacked vision.” However, the longer they had been blind, the shorter their memory and the more hazy their visual impressions were.

The emotions and themes of the dreams were more or less similar. There were no notable differences between the groups in how much they dreamed of positive and negative social situations or aggressive interactions.

Another thing that stood out was that nightmares were notably more common in congenitally blind people. Common examples were getting lost, being hit by a car, losing their guide dogs, or falling into holes. The researchers didn’t delve too deep into why this was, however they speculate these dreams act as a “shock absorber” for the anxieties they encounter everyday. As so many of their day-to-day problems revolve around senses, or lack thereof, it makes sense that the sensory output of their dreams reflects this.  

In a YouTube video, Tommy Edison – a blind YouTuber and film critic who talks about his personal experiences in a down-to-earth and often hilarious dad-joke way – discussed whether he sees in his dreams: “I have been blind since birth, so I have never seen in my life, so my subconscious doesn’t know what it’s like to see either. I mean, the way it works for me is just the way my life occurs. It’s all smell, sound, taste, and touch.”

“I mean just like you guys, weird things happens in my dreams," he added. "Here I am, it’s the bottom of the ninth, runners on second and third, two men away, then all of a sudden it's my seventh birthday."

In another one of his videos, he answers a question about a common myth: Can blind people experience visuals when on psychedelic drugs?

Of course, his experiences are only anecdotal, but Tommy says for him it’s a similar story to dreaming – if his brain doesn’t know how to see, “a drug wouldn’t be able to make me see. If it could, don’t you think I’d take it every day!?”