Typically, when we dream, we are not aware that we are dreaming, and the most unlikely events, characters, and environments seem real to us.
But now and again, some of us realize that we are in a dream as we are dreaming. This phenomenon is called “lucid dreaming,” and it has stirred the interest of researchers and the public alike.
Learning to control aspects of your dreams can be a great way of exploring activities you could never do in real life, facing and overcoming fears, and learning more about your subconscious.
In a previous special feature on Medical News Today, we have explained what lucid dreams are, talked about some techniques you can apply to achieve them, and looked at whether there are any risks associated with this practice.
In this article, we take that discussion a step further, looking at some of the science behind lucid dreaming.
So if you are interested in finding out how common lucid dreams are, who is more prone to having them and why, and what happens in the brain during a lucid dream, read on.
How common are lucid dreams?
It remains unclear how many people experience lucid dreams, but researchers have provided rough estimates based on personal reports they accessed through their studies.
A 2017 study published in the journal Imagination, Cognition and Personality: Consciousness in Theory, Research, and Clinical Practice referred to estimates suggesting that in a representative population, 51% of the individuals had experienced a lucid dream at least once in their lives, and about 20% experienced lucid dreams at least once a month.
The same study notes that people are more likely to experience spontaneous lucid dreams in their childhood, starting at about 3 and 4 years old. However, the likelihood of lucid dreaming begins to decline in early adolescence.
“After the age of 25, spontaneous onset of lucid dreaming appears to be very infrequent,” the study authors write.
The researchers who hail from the Universities of Mannheim and Heidelberg, both in Germany investigated whether or not personality traits could help predict a person’s likelihood of experiencing lucid dreams.
The study found that openness to an experience correlates positively with lucid dreaming frequency. However, agreeableness a personality trait that often indicates a person’s level of friendliness and tact in interpersonal relationships — does not.
The study also identified that neuroticism a personality factor that often presents as strong moods, anxiety, and depression had associations with a higher frequency of lucid dreams.
Lucid dreams and sleep disturbances
Denholm Aspy, Ph.D., who researches lucid dreaming, spoke to MNT and suggested that certain neurophysiological or neurochemical factors may also render a person more likely to experience spontaneous lucid dreams.
More often than not, lucid dreaming occurs during the REM (rapid eye movement) phase of sleep, which is also when many regular dreams occur. It is possible that neurochemical peculiarities may play a role in “switching on” parts of our consciousness when they would generally be “switched off.”
“I’m speculating a little bit here, but some people might just tend to produce more of the neurotransmitters that pause REM sleep, typically acetylcholine,” Aspy told us.
“You might have some random variation in neurology or neurochemistry I know that people with narcolepsy tend to have a lot more lucid dreams than the average person, and they’re having a lot of sleep disturbances,” he went on to say.
Some anecdotal experiences, as well as some studies, suggest that lucid dreaming may have more in common with the experience of sleep paralysis than that of regular dreaming.
In sleep paralysis, the mind awakens to a certain degree, while the body remains asleep and unable to move. When that happens, individuals usually experience very realistic hallucinations, as though the content of a dream had “leaked” into the real world.
For instance, a 2017 study — featured in the Journal of Sleep Research — found a significant positive correlation between sleep paralysis and lucid dreaming frequency in a cohort of 1,928 adult participants.
“It is likely that these sleep experiences are underlined by similar neurophysiology,” the study authors write.
They also note that “[d]issociative experience was the only common predictor of both sleep paralysis and lucid dreaming frequency, indicating that individuals who experience both unusual sleep experiences also experience greater dissociative experiences in daily life.”