Imagine waking up from a dream, heart racing, breathing heavy, and feeling an overwhelming sense of dread.
For many people, nightmares are a rare occurrence, but for some, they are an almost nightly experience.
A recent study conducted by the University of Copenhagen and Glostrup Hospital has brought to light some truly surprising findings:
people who are born blind experience far more nightmares than those who can see—and even more than those who lose their sight later in life.
The statistics are startling.
On average, 25% of the dreams reported by people who were born blind are nightmares.
In contrast, only about 6% of the dreams of people with normal vision are classified as nightmares.
This difference is not just a statistic; it gives us deep insights into how our brains function and process emotions, even when we’re asleep.
The Science Behind the Nightmare Epidemic
According to the study’s lead author, Amani Meaidi, a researcher at both the University of Copenhagen and Glostrup Hospital, the findings confirm a long-standing hypothesis:
our nightmares are often linked to the emotions and stress we experience in our waking lives.
“The study confirms an already existing hypothesis that people’s nightmares are associated with emotions they experience while awake.
And blind people apparently experience more threatening or dangerous situations during the day than people with normal sight,” Meaidi explains.
This connection between waking experiences and nightmares suggests that the more threatening or dangerous situations we encounter during the day, the more likely we are to experience disturbing dreams at night.
For people who are blind from birth, this could mean their brains are processing heightened fears, based on a lifetime of navigating a world that is less predictable and more challenging.
The study, which tracked the dreams of 50 participants over a period of four weeks, included 11 people who were born blind, 14 who had lost their sight later in life, and 25 individuals with normal vision.
Each participant kept a record of their dreams, revealing fascinating insights about the role of sight in shaping the content of our dreams.
The Role of Sight in Dreaming
One of the most remarkable aspects of the study is the discovery that people who were born blind do not dream of visual content at all.
Without the sensory input of sight, their dreams are filled with other senses: sounds, tastes, smells, and physical sensations like touch.
This highlights the significant role sensory experiences play in shaping our dreams. Meaidi notes, “The study also points out that the sensory input and experiences we get while awake are decisive when it comes to what we dream.
So people without visual sensory input dream to a much greater extent in terms of sounds, tastes, smells, and touch.”
However, despite their lack of visual imagery, people who were born blind still experience nightmares at a much higher rate than people who can see.
For these individuals, dreams often revolve around threats they encounter in daily life, such as being run over by a car or spilling coffee.
The emotional core of these nightmares is often a profound sense of helplessness, as 41-year-old Heidi Andersen, a participant in the study who was born blind, describes:
“At the core of my nightmares is a feeling of complete helplessness.”
The Evolution of Sight and Dream Content
Interestingly, the study also shed light on the experiences of people who lost their sight later in life.
These individuals reported dreams that still included visual elements, although over time, as their blindness persisted, the visual content of their dreams gradually decreased.
For those who lost their sight later in life, the percentage of nightmares was also significantly lower, around 7%, compared to the 25% experienced by those who were born blind.
People with normal vision, meanwhile, reported nightmares just 6% of the time, and all of their dreams were image-based.
This suggests that sight—whether present or absent—has a profound influence on how we process and interpret the world around us, even in our sleep.
Why Are Blind People More Likely to Have Nightmares?
You might wonder: Why do blind people, particularly those born blind, experience such a high frequency of nightmares?
The study suggests that it could be because people who are blind face more perceived threats or challenges in their waking lives than those who can see.
Whether it’s navigating unfamiliar spaces, relying on non-visual cues to interpret their environment, or simply encountering the day-to-day struggles that sighted people may take for granted, these heightened stressors may manifest as nightmares during sleep.
Albert Gjedde, a neuroscientist from the University of Copenhagen who was not involved in the study, offers an insightful explanation.
He believes that because people who lose their sight later in life have already had years of visual experience, their brains might not process threats in the same way as those who have never seen the world around them.
“Because people who lose their sight later in life have previously seen their surroundings, it might be that their brains do not experience being threatened by circumstances to the same degree as people who are born blind,” Gjedde says.
“For this reason, they may not need to process impressions from everyday life to the same extent by means of nightmares.”
This idea could explain why individuals who were born blind have a heightened need to process everyday challenges through their dreams—resulting in a higher frequency of nightmares.
These dreams, often intense and emotionally charged, could serve a vital purpose in helping people navigate their world, process stress, and ultimately find a sense of confidence and control.
The Impact of Nightmares on Mental Health
Although the prevalence of nightmares among people who are born blind may seem alarming, the study also found no evidence that these frightening dreams lead to significant anxiety or depression.
Participants with more frequent nightmares did not show signs of pronounced psychological distress, suggesting that, while the nightmares themselves are distressing, they do not seem to have a lasting negative impact on overall mental health.
This finding is somewhat reassuring, as it suggests that the occurrence of nightmares—while unpleasant—may simply be a normal part of the process by which our brains work through complex emotions and fears.
In fact, nightmares may even play a vital role in emotional regulation and cognitive processing.
What Does This Study Teach Us?
This study offers us a unique glimpse into the world of dreams, particularly for those who experience the world differently.
It highlights the profound connection between sensory experiences and dreaming, while also challenging the way we think about the purpose of nightmares.
Far from being just unsettling episodes, nightmares may serve as an important mechanism for our brains to process stress and emotional challenges—particularly for those who are born blind and must navigate a world that is both physically and emotionally more demanding.
As we continue to explore the mysteries of the brain and the role of dreams in our lives, this research serves as a reminder that the way we dream is deeply shaped by the world around us—and that our brains will stop at nothing to ensure we learn, adapt, and survive.
Conclusion: The Brain’s Struggle for Survival
Ultimately, the study on nightmares in people who are born blind underscores an essential truth about the human experience:
our brains are constantly working, even while we sleep, to help us process the world and learn how to survive it.
For those without sight, the nightmares may be more frequent, but they are a testament to the brain’s resilience and its ability to adapt to challenges.
Whether through dreams or waking life, the brain’s drive for survival remains unyielding, no matter what sensory input it has—or lacks.
This research sheds new light on how our minds interpret the world and cope with adversity, challenging us to rethink our understanding of dreams, emotions, and the complex interplay between our sensory experiences and mental health.
It reminds us that dreams are not merely random occurrences but critical pieces of a larger puzzle in our ongoing journey to make sense of the world and our place within it.
