In a new study, researchers were able to communicate with sleeping subjects in real time. These people, “lucid dreamers”, could follow instructions and consciously respond to outside stimuli during their dreams.
Everyone dreams, but we do not yet fully understand why. This field of study is indeed complicated to the extent that most of us forget or distort the details of our dreams. This is in part because the brain does not form many new memories during sleep and has limited capacity to store information when waking up.
To overcome these obstacles, researchers from INSERM, AP-HP, Sorbonne University and CNRS with several American, German and Dutch groups, tried to communicate with people while they were still dreaming. As part of this work published in the journal Current biology, they called on “lucid dreamers”, those people who are aware that they are dreaming and can sometimes influence the unfolding of their dreams.
Note that approximately 23% of people have a lucid dream once a month or more, according to a research article published in 2016 in the journal Consciousness and cognition.
But then, why lucid dreamers? Studies have already shown that these people are able to inform about their lucidity thanks to an ocular code previously learned. In other words, we already know that these subjects can communicate with the outside during their dreams, one way. The question is: can we establish two-way communication?
Four distinct experiences
To find out, the researchers placed electrodes on the participants’ skulls to measure their brain waves, next to their eyes, to track their eye movements, and on their chin to measure muscle activity. They then used this data to determine when subjects entered the REM phase, when lucid dreams are most likely to occur.
During the experiment, the researchers were able to set up several types of stimulation to hope to establish a two-way communication. Among them, they tested open-ended questions asked aloud, tactile stimuli (physical tapping), flashing lights, beeps or even semantic discrimination tasks (distinguishing single words). The sleeping subject then had to respond to these stimuli with distinctive eye or facial movements interpreted by the electrodes.
For this study, four independent laboratories in the United States, Germany, France and the Netherlands conducted four separate experiments.
Conscious responses to external stimuli
As part of this work, after many attempts, six participants out of 36 would have been capable of responding to a number of stimuli while they were sleeping. One of them even pointed out when he woke up that the experimenter’s voice came to him like a “divine voice” during his dream in which he was partying with friends.
The results on a possibility of communication with dreamers open “perspectives to identify physiological markers of consciousness and dreaming and to decode the activity of our brain during the dream experience, in order to better understand the role of dream and sleep“, Writes Iserm. This first step may therefore one day be able to unravel the mystery of our dreams.
The researchers also suggest that the method used in these experiments could be adapted to potentially tailor a person’s dream to a specific need such as learning or dealing with emotional trauma.