The early 1990s movie “Darkman” was based on the premise that a lack of sensory input leads to higher levels of depression. Despite merely being a trope to make the character seem interesting, the writers of the movie may have actually been on to something, according to a recent Danish study. Conducted at the Danish Centre for Sleep Medicine, a study on people whom were born blind was not only able to confirm an existing hypothesis about dreaming and stress, but found them to be four times more likely to experience nightmares as well.
The study focused on 11 people who were born blind and 14 who lost their vision later in life against a control group of 25. The participants were asked to record their dreams over a period of four weeks; although the authors expected dreams in general to be more vivid to the blind groups, they surprisingly found nightmares to be almost four times as prevalent in the naturally blind group. Despite showing no signs of depression or negativity relative to the control group, a quarter of the natural blind group’s dreams were reported to be nightmares (to their surprise as much as the researchers), while the rest of the blind group as well as the control had nightmares six to seven percent of the time.
“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,” said Amani Meaidi, lead author of the study.
The nightmares reported by the blind group were related to fears experienced throughout the day, such as getting in a car accident or an embarrassing situation. The researchers suggest that the frequency of nightmares in the born-blind group is caused by the higher amounts of sensory input from their remaining senses, leaving them with more information to process during their dreams. Where dreams are believed to be mostly sensory experiences that help us process thoughts and images incurred during the day, nightmares exist to process our negative emotions. Because of their more emotional nature, nightmares rely less heavily on visual stimuli; for people who were born blind and have no objective concept of what their reality looks like, they simply have less information to process at night.
A lack of visual stimuli can leave the mind open to excessive rumination, experiencing more emotions in the process à la Darkman (1990). With this in mind, it is not too surprising that natural-born blind people spend more of their time processing their emotions in nightmares than regular people. Although the “unnatural” blind group still experienced some visual images in their dreams (due to their habit to assign archetypal images for their daily experiences), they reported fewer visual dreams over time.
Fear and the dark
In addition to a lack of visual input that makes nightmares more prevalent, the researchers also suggest that the higher frequency of bad dreams is due to the way that blind people process threatening situations during the day. With physically threatening situations such as crossing a street or even entering a room, blind people may be more prone to anxiety, or at least negative rumination.
When confronted with a lack of crucial visual information, our minds tend to play it conservatively, favoring fearful or at least more cautious approaches. This can be said about the way blind people experience social situations as well; with over half of communication being nonverbal (body language, facial expressions, etc.), it can be much more difficult for them to pick up on the subtle physical cues that are part of basic conversation. This lack of information can not only leave them more prone to frustration from trying to communicate in general, but can lead to more rumination about what the person thinks as well.
The researchers also found that the natural blind group experienced more sounds, tastes, smells and tactile senses than the others, supporting the age old hypothesis that losing one sense causes the others to compensate. They also note that despite the high rate of nightmares, the blind participants had no signs of anxiety or depression, reporting no problems or excessive negative emotions in their daily lives.
Sovereign Health understands the importance of dreaming/REM sleep in recovery from addiction and anxiety-based mental health disorders such as insomnia. By instituting curfews in addition to holistic, cutting edge approaches to brain wellness, we ensure that our patients are given adequate time to recover from any brain damage incurred in the past. If you would like more information, feel free to browse the reviews section or the rest of our site.
Written by Chase Beckwith, Sovereign Health Group writer