If you’ve ever crammed for an exam just before bedtime, you may have tried something dream
researchers have been attempting for decades: coaxing knowledge into dreams. Such efforts
have had glimmers of success in the lab. Now, brands from Xbox to Coors to Burger King ar
e teaming up with some scientists to attempt something similar: “Engineer” advertisements
into willing consumers’ dreams, via video and audio clips. This week, a group of 40 dream
researchers has pushed back in an online letter, calling for the regulation of commercial
dream manipulation.“Dream incubation advertising is not some fun gimmick, but a slippery s
lope with real consequences,” they write on the op-ed website EOS. “Our dreams cannot beco
me just another playground for corporate advertisers.”Dream incubation, in which people us
e images, sounds, or other sensory cues to shape their nighttime visions, has a long histo
ry. People throughout the ancient world invented rituals and techniques to intentionally c
hange the content of their dreams, through meditation, painting, praying, and even drug us
e. Greeks who fell ill in the fourth century B.C.E. would sleep on earthen beds in the tem
ples of the god Asclepius, in the hopes of entering enkoimesis, an induced state of dreami
ng in which their cure would be revealed.Modern science has opened a whole new world of po
ssibilities. Researchers can now identify when most people enter the stage of sleep where
much of our dreaming takes place—the rapid eye movement (REM) state—by monitoring brain wa
ves, eye movements, and even snoring. They have also shown that external stimuli such as s
ounds, smells, lights, and speech can alter dreams’ content. And this year, researchers co
mmunicated directly with lucid dreamers—people who are aware while they are dreaming—getti
ng them to answer questions and solve math problems as they slept.“People are particularly
vulnerable [to suggestion] when asleep,” says Adam Haar, a cognitive scientist and Ph.D.
student at the Massachusetts Institute of Technology who co-authored the letter. Haar inve
nted a glove that tracks sleep patterns and guides its wearers to dream about specific sub
jects by playing audio cues when the sleeper reaches a susceptible sleep stage. He says he
has been contacted by three companies in the past 2 years, including Microsoft and two ai
rlines, asking for his help on dream incubation projects. He helped with one game-related
project, but says he wasn’t comfortable participating in any advertising campaigns.Work by
Harvard University dream researcher Deirdre Barrett has also attracted corporate attentio
n. In a 1993 study, she asked 66 college students taking a class on dreams to select a pro
blem of personal or academic relevance, write it down, and think about it each night for a
t least a week before going to bed. At the end of the study, nearly half reported having d
reams related to the problem. Similar work published in 2000 in Science, in which Harvard
neuroscientists asked people to play several hours of the computer game Tetris for 3 days,
found that slightly more than 60% of the players reported having dreams about the game.Th
is year, Barrett consulted with the Molson Coors Beverage Company on an online advertising
campaign that ran during the Super Bowl. Following her instructions, Coors, which feature
s mountains and waterfalls on its logo, had 18 people (12 of them paid actors) watch a 90-
second video featuring flowing waterfalls, cool mountain air, and Coors beer right before
falling asleep. According to a YouTube video documenting the effort, when the participants
awoke from REM sleep, five reported dreaming about Coors beer or seltzer. (The result rem
ains unpublished.)Barrett told Science she does not consider the intervention to be a real
“experiment,” and she acknowledged in a recent blog post that the company’s ad used scien
tific terminology “with overtones [of] mind-control experimentation,” against her advice.
She also thinks advertising strategies like these will have little practical impact. “Of c
ourse you can play ads to someone as they are sleeping, but as far as having much effect,
there is little evidence.” Dream incubation “doesn’t seem very cost effective” compared wi
th traditional advertising campaigns, she says.That doesn’t mean that future attempts coul
dn’t do better, says Antonio Zadra, a dream researcher at the University of Montreal who s
igned the statement. “We can see the waves forming a tsunami that will come, but most peop
le are just sleeping on a beach unaware,” he says. Harvard neuroscientist Robert Stickgold
, who ran the Tetris study, is even more emphatic: “They are coming for your dreams, and m
ost people don’t even know they can do it.”The letter writers say that because there are n
o regulations specifically addressing indream advertising, companies might one day use sma
rt speakers like Alexa to detect people’s sleep stages and play back sounds that could inf
luence their dreams and behaviors. “It is easy to envision a world in which smart speakers
—40 million Americans currently have them in their bedrooms—become instruments of passive,
unconscious overnight advertising, with or without our permission,” says the letter, whic
h the writers have sent to U.S. Senator Elizabeth Warren (D–MA).Such a world is worth prep
aring for, says Dennis Hirsch, a professor of law and privacy expert at Ohio State Univers
ity, Columbus. But he thinks the U.S. Federal Trade Commission Act, which prohibits agains
t deceptive advertising “in any medium,” already applies to indream advertising. He adds t
hat U.S. law is evolving to include more specific prohibitions on subliminal messaging.Tor
e Nielsen, a dream researcher at the University of Montreal who did not sign the statement
, says his colleagues have a “legitimate concern.” But he thinks interventions like this w
on’t work unless the dreamer is aware of the manipulation—and willing to participate. “I a
m not overly concerned, just as I am not concerned that people can be hypnotized against t
heir will,'” Nielsen says. “If it does indeed happen and no regulatory actions are taken t
o prevent it, then I think we will be well on our way to a Big Brother state … whether or
not our dreams can be modified would likely be the least of our worries.”