In my dream, I am losing my teeth. They fall out one by one, and although I try to catch them, they slip through my fingers into the tall grass at my feet. I want to search for them, but my limbs feel too heavy to move. I believe I’ll never be able to speak again if I can’t find my teeth. I wake up freaked out and feel uneasy for the rest of the morning.
Chances are, you’ve had a dream like this too: a nightmare about falling from a high place, being chased by mysterious creatures, or taking an exam you’ve completely forgotten to study for. We think of these dreams as inevitable. We’ve accepted that when we close our eyes and venture off into dreamland, we relinquish all control of our minds.
But what if we could control what we dream about?
With the appropriate technological nudges, that’s starting to become possible. The field of dream engineering harnesses virtual reality, brain stimulation, sounds, and smells to unravel the secrets of manipulating our dreams. Scientists who study dream engineering believe it could have serious uses, from treating nightmare disorders to improving mood and even enhancing memory. And as technology improves, the chance to influence our sleeping state is expanding beyond the lab. Thanks to advances in virtual reality and wearable devices, we might soon even be able to engineer our dreams at home.
The question of how to influence dreams has interested neuroscientists for decades. “To me, it’s a mystery. It’s always been a mystery,” says Tore Nielsen, director of the Dream and Nightmare Laboratory at the University of Montreal, who has been studying dreams for 30 years.
Early attempts to crack the code were as much wishful thinking as science. In 1969, researchers at the Maimonides Medical Center in Brooklyn experimented with the idea that dream content might be altered by telepathic communication. Subjects spent the night sleeping in a lab while another person (a “transmitter”) attempted to mentally communicate the content of an art print into their dreams. The study did purport to find evidence that telepathy affected dreams. But its conclusion likely wouldn’t pass muster under today’s scientific publishing standards.
Since then, researchers have kept at it, with the help of evolving technologies — from motion-detecting wrist sensors used in the 1990s to today’s sleep-monitoring smartwatches and apps.
Scientists who study dream engineering believe it could have serious uses, from treating nightmare disorders to improving mood and even enhancing memory.
Advancements in virtual reality have also expanded scientists’ ability to put big ideas into their subjects’ minds. Inducing dreams about flying, for instance, has traditionally been difficult, because we often dream about things we’ve done during the day. In a world powered by VR, however, anything is possible.
In a 2020 study, researchers from Nielsen’s laboratory had participants complete an immersive VR task: They flew over a mountain landscape, moving their arms left and right to navigate through a series of green targets. Just 15 minutes of VR increased the likelihood that people would dream about flying — a type of dream that often provokes excitement and joy.
Other senses can be targeted for dream manipulation, too. Harvard and MIT scientists recently created Dormio, an electronic device worn on a participant’s wrist and fingers, which uses sound to encourage specific dreams. As users slip from wakefulness into the lightest stage of sleep, sensors on their hands monitor changes in muscle tone, heart rate, and perspiration. Users are then awakened and the device whispers a dream prompt, after which they return to sleep.
The proof-of-concept study for the Dormio was successful: After being prompted to “think of a tree,” two-thirds of participants reported that their dreams included some reference to trees. “I was following the roots, and the roots were transporting me to different locations,” reported one. “I could hear the roots of the tree pulsating with energy.”
In the future, the Dormio creators hope users will be able to record their own prompts, inducing dreams about whatever they choose.
Not all dream research is so high-tech. Researchers also rely on basic sensory stimulation, since certain sensations still reach us when we’re asleep — as when the sound of an alarm clock, the sensation of needing to pee, or a distinctive smell becomes part of a dream.
“It’s common to say that when you’re dreaming, you’re completely cut off from the external world,” says Michelle Carr, a postdoctoral associate in the Sleep and Neurophysiology Research Laboratory at the University of Rochester. “But you’re still in touch with your body, right? And your brain [is] constantly processing what’s going on in your body, even when you’re asleep.”
Carr participated in a 2019 study in which researchers inflated blood pressure cuffs on sleepers’ legs. During the experiment, she says, “I dreamed that my cat was walking around the bottom of my leg — you know how cats rub up against you? So that got incorporated — that’s a pleasant dream.”
In one 2009 study, subjects in rapid eye movement (REM) sleep — a phase of sleep in which dreaming frequently occurs — were exposed to either the scent of roses or the odor of rotten eggs. Even though no one reported smelling anything while asleep, those who smelled roses had more emotionally positive dreams, while those who got rotten eggs had more unpleasant ones.
Other experiments bypass sensory stimulation and go to the brain more directly. Researchers at the University of Dundee in Scotland used electrodes placed on the skull to stimulate the motor cortex — the region of the brain that plans and controls movement — during REM sleep. During such stimulation, study participants had more dreams involving motion, such as running, surfing, or playing football.
What is the purpose of manipulating our dreams? The possibilities range from improving the quality of our sleep to helping solve problems and boost cognitive function during our waking hours.
Dreaming may play an important role in learning, remembering, and problem-solving. “As we’re falling asleep, we tend to replay the events from the day,” says Robert Stickgold, a sleep researcher at Harvard who worked on the Dormio project. “That sleep-onset period is where we identify [our brain’s] chores for the night.” With the right psychological nudges, we may be able to tag these concepts — say, learning a piece of music or solving a technological problem — for processing during the night.
Nielsen, the University of Montreal scientist, agrees that may be possible. “There is more and more evidence that when we dream about a new task that we’ve just learned, we’ll do better on that task later on,” he says.
Dreaming may be closely linked with mental health in ways that we do not yet fully understand. REM sleep may play an important role in emotion regulation, and research shows that frequent disturbing dreams or nightmares can be associated with anxiety and suicidal ideation. Manipulating dreams could give scientists greater insight into this connection and open new avenues for treating mental health disorders.
And because the types of dreams we have may affect our daytime well-being, scientists see huge potential in helping people cut down on nightmares. “The mood that you feel in the morning, that persists throughout the day,” says Carr. “With nightmares, you will experience a lot of distress, immediately responsive to the nightmare. If the nightmare is related to something in your waking life, it can stay with someone all day.”
People with especially distressing nightmares “often avoid sleep, or they’re afraid of sleep,” she adds.
Already, the FDA has approved a prescription-only app, for patients diagnosed with PTSD, that wakes you up when you’re having a nightmare. But there’s also hope that dream manipulation will be able to help people create a safer, happier dreamscape for themselves. Some researchers wonder if virtual reality experiences during the day could help turn terrifying falling nightmares into pleasant flying dreams or prompt dreamers to defeat a nightmare attacker with jujitsu. Nielsen’s Montreal lab continues to investigate how virtual reality can influence our dreams. But so far, therapeutic applications of dream engineering are still in the early research stages; Carr says this is one of the next big challenges for the field.
With increasing use of VR and wearable technology, there’s also a growing chance that influencing dreams could become a form of recreation — or, at least, something people could do from the comfort of their own beds. Today, smartwatches and apps that monitor sleep are available for home use, so it might not be long before dream-influencing apps are available.
Personally, I’m looking forward to dreams about flying in the Himalayas and exploring alien worlds rather than dreaming (again!) that I’ve arrived at work without any pants.