A few years ago when I was reading “The Interpretation of Dreams” by Sigmund Freud, I came across a stimulating claim – “The interpretation of dreams is the royal road to a knowledge of the unconscious activities of the mind.” Since dreaming is a fairly common mental activity, it corroborates Freud’s theory of psychoanalysis through a persons’ dreams. Although most people dream and that has been widely studied, there are finer nuances to the science of lucid dreaming that not all people have experienced.
Lucid dreaming is one such subject that has had scientists and research intrigued for decades. Lucid dreaming is the experience of achieving conscious awareness of dreaming while still asleep. Lucidity, by definition means intelligibility or comprehensibility, implying that in this state, a person can fully comprehend the fact that it is a dream and that they are asleep. They also can understand and control the dream i.e. change the narrative of the dream.
This phenomenon, although not completely researched, is not recent. Claims are that the concept dates back to the Paleolithic era, roughly 2.5 million years ago. Western literature has evidence of Aristotle or probably first mentioning it in the fourth century BCE in the treatise On Dreams in Parva Naturalia. Here, he states: “often when one is asleep, there is something in consciousness which declares that what then presents itself is but a dream”.
Similarly, in Eastern cultures, there are reports of individuals engaging in practices to cultivate awareness of dream and sleep states since the 20th century. These practices include meditative techniques specifically designed to “apprehend the dream state”.
However, since its discovery, there have been significant milestones in the study of the concept. The first one was in 1913 when the modern nomenclature of ‘lucid dream’ was coined by the Dutch psychiatrist Frederik Van Eeden. He defined lucid dreams as dreams in which “the reintegration of the psychic functions is so complete that the sleeper remembers day-life and his own condition, reaches a state of perfect awareness, and is able to direct his attention, and to attempt different acts of free volition”.
Eeden claimed that he had his first lucid dream in the June of 1897, adding that the sleep is undisturbed, deep and refreshing.
Celia Green researched lucid dreaming in 1968, where she suggested that lucid dreams are associated with REM sleep. She was the first to link lucid dreams to false awakenings. Her work has helped to shed light on the mechanisms that lead to these experiences. In 1975, Keith Hearne exploited the nature of Rapid Eye Movements when he worked with an experienced lucid dreamer.
Under his technique that involved monitoring eye movements through an electrooculogram, he studied how to induce the dreamer to send a message directly from dreams to the waking world.
In the 1970s, when Stanford psychophysiologist Stephen LaBerge began developing techniques that allowed himself and others to control their dreams, he was met with skepticism and doubt from his colleagues and friends.
This skepticism was a byproduct of the fact that there was no proof that LaBerge and others were truly having lucid dreams. It was a branch of neuroscience not many had ever seen any evidence of. Many researchers at the time thought lucid dreaming was not even scientifically plausible. That then changed when LaBerge and other researchers had an empirical breakthrough. They found a few lucid dreamers who volunteered to sleep in a lab with various sensors attached to their bodies, including their eyelids.
One of these studies, published in 2018, studied smooth pursuit eye movements (or the slower tracking movements in which the eyes remain fixated on a moving object) during tracking of a slow-moving visual target during lucid dreams in REM sleep. The sleeping study participants were instructed to move their eyes left and right twice to check if they were lucid. This was followed by the participants holding out an arm in a thumbs up position, while still dreaming. These participants also used their thumb to draw a circle in the air, tracking that circle with their eyes – all while asleep and in their dreams! Outside of the dream, in the lab, their arms were stationary, but their eyes were not. As their eyes moved in circles within the dream, their actual eyes also traced those movements, as recorded by the sensors.
This lucid dreaming study helped the researchers investigate highly similar smooth pursuit tracking that were observed during both waking perception and lucid REM sleep dreaming. This is different from the characteristically rapid (saccadic) tracking observed during visuomotor imagination (i.e. the use of one’s imagination to simulate an action, without physical movement – often used in neurological habilitation, sports training, and for psychological research).
The findings of this study suggest that the visual imagery that occurs during REM sleep is more similar to perception than imagination, at least in the context of eye movements. The data also showed that the neural circuitry of smooth pursuit movement can be driven by a visual percept in the absence of retinal stimulation.
Additionally, it was also seen that within REM sleep dreams, these specific voluntary shifts in the direction of experienced gaze are also accompanied by corresponding rotations of the physical eyes.
So, now the question is what causes ones’ brain to dream lucidly. Let us try to understand what happens in our brain when we are lucid dreaming!
The typical human brain goes through different stages of sleep when one dozes off. Usually, REM sleep happens 90 minutes after you fall asleep and then the cycles repeat every 90 minutes or so thereafter. Rapid eye movement (REM) sleep is a stage of sleep associated with dreaming and memory consolidation. It was first discovered when scientists observed that there were distinct periods of rapid eye movements from side to side in sleeping infants.
During REM sleep, your brain is so active that your brain waves look similar to when you’re awake. All that brain activity is what makes REM the most likely phase for dreaming to occur, lucid dreams included.
Your brain is even more active during a lucid dream than a non-lucid dream. A 2017 study, “Exploring the neural correlates of dream phenomenology and altered states of consciousness during sleep” published in the journal Neuroscience of Consciousness by Julian Mutz, found that while you lucid dream, the regions in your brain responsible for insight, attention, and agency activate similarly to when you’re awake.
(Source; Image 1 – Brain regions showing increased activity during lucid REM sleep contrasted with non-lucid REM sleep.)
The prefrontal cortex, or the frontopolar cortex (FPC) is the part of the brain responsible for lucid dreaming. This area in the brain is also responsible for higher-order cognitive functions, like planning and decision-making. In terms of brain activity, lucid dreaming occurs when the frontopolar cortex is active during sleep, thus allowing the dreamer to be aware of the fact that they are dreaming and control the narrative of the dream.
There is another part of the brain that has been linked to lucid dreaming. This is the amygdala (within the medial temporal lobe or the ventrolateral PFC), which helps us process emotions. Researchers have discovered that people with more activity in their amygdala during sleep are more likely to have lucid dreams. This could be because the amygdala processes fear and anxiety, thus increasing awareness while the subject is dreaming.
The precuneus is also thought to play a role in lucid dreaming for the following reasons – It is highly active during REM sleep when most dreams occur; is also connected to other brain areas important for dream recall and self-reflection, for instance the hippocampus and prefrontal cortex; and it also is critical for several aspects of dreaming, like conscious awareness and self-reflective processing. The precuneus allows us to have such vivid and complex dreams.
In the case of the inferior parietal lobe (or the cuneus) and its role in lucid dreaming, researchers claim that the activity of neurons in the inferior parietal lobules may be critical to the awareness and control that happens when a person is in a lucid dream. So far, research suggests that people with more active inferior parietal lobules are more likely to have lucid dreams.
However, these claims still need to be verified with additional empirical research and studies. Lastly, the supramarginal gyrus (or the occipito-temporal cortex) plays a role in lucid dreaming owing to its involvement in the somatosensory (i.e. relating to a sensation in any part of the body) association cortex. Researchers suggest that it may play a role in facilitating communication between dreamers and others during a lucid dream.
Typically, when we are asleep, REM sleep is characterized by frequencies in the theta (4–8 Hz), beta (16–32 Hz), and gamma (>32 Hz) ranges. When awake, most waves of 8 Hz and higher frequencies are normal findings in the EEG of a typical adult.
A study was conducted in 2008 to study physiological correlations of lucid dreaming and EEG (electroencephalogram) levels of the brain that measure brain activity. The results showed that when the participants become lucid, they shift their EEG power, especially in the 40-Hz range and especially in frontal regions of the brain.
Pre-sleep autosuggestion occurs when one creates an idea or reality on their own, and takes to the hypnotic or subconscious adoption of this self-originated idea, for instance through repetition of verbal statements to oneself in order to change behavior. The above study suggested that the shift in the EEG levels could be partially due to pre-sleep autosuggestion.
This indicates that REM dream consciousness, which is largely automatic, i.e., spontaneous, involuntary, and intrinsic, could be a result of volition. This study basically claimed that lucidity occurs in a state with features of both REM sleep and waking – thus deeming it to be a ‘hybrid’ state. Having gone through the physiology of the brain during lucid dreaming, one natural question that arises is if we can master lucid dreaming. Think of lucid dreaming, how do we make ourselves have a lucid dream?
Paul Tholey proposed seven awareness criteria of lucid dreaming that can be stated as follows:
The above criteria, also called Tholey’s 7 Klartraum Criteria, define the conditions to identify stages of Lucid Dreaming or Pre-lucid dream. Pre-lucid dreaming (PLD), or the beginning stages of inducing the lucid dreaming process leads the dreamer to ask the question: if he/she is asleep and dreaming. The dreamer may or may not arrive at the correct conclusion in this stage.
The awareness criteria 1 and 2 mentioned above, are crucial for the experience of a lucid dream (LD). If only awareness criteria 1 applies, it is likely a PLD, since all others imply some level of self-reflective capacity which in turn can lead to further cognitive capacities. Awareness criteria 5–7 are not essential for the definition for the PLD and LD, but can be part of a PLD (distinguishing the PLD from the non-lucid dream), and the LD.
In the study of Tholey’s 7 Klartraum Criteria, neurological evidence was collected and visualized (see image 1).
This study showed that Lucid dreaming has the ability to increase awareness and mental control of the dreamer. There was evidence to support the seven awareness criteria that during LD, not a single brain structure, but a whole network of brain regions is activated.
A case study published in 2012 claimed that we can induce within someone, the ability to lucid dream inside the noisy and constrained environment of an fMRI scanner. This was a big change from what we knew prior to this study. The participant of this study was a frequent lucid dreamer.
The subject was instructed to shift his gaze from left to right whenever he “woke up” in his dream – a dream motion that is also known to translate to real eye movements. This indicated to the researchers to identify the moment at which he had achieved lucidity.
The brain scans from this experiment revealed heightened activity in a group of brain regions, including the anterior prefrontal cortex. These areas are normally less active during a typical REM sleep cycle. However, they became much busier whenever the participant entered his lucid dream, suggesting a heightened reflection and self-awareness.
There was yet another study, “Pre-sleep treatment with galantamine stimulates lucid dreaming: A double-blind, placebo-controlled, crossover study” published in 2018, which studied the effects of the alkaloid galantamine, on peoples’ ability for dream recall, cognitive clarity, control, positive emotion, vividness and self-reflection. The participants of this study slept for a few hours before waking. They then took a small dose of the drug, or a placebo, before practicing a few visualization exercises that are also thought to slightly increase the odds of lucid dreaming.
They went back to sleep after around 30 minutes. Just 14% of the participants who took a placebo managed to gain awareness of their dream state, compared to 27% of those who took a 4mg dose of galantamine, and 42% of those who took an 8mg dose.
The results of this study showed that galantamine increases the frequency of lucid dreams in a dose-related manner. Moreover, this study also indicated that one of the most effective methods for inducing lucid dreams available today is by integrating the approach of taking galantamine in the last third of the night with at least 30 minutes of sleep interruption and with an appropriately focused mental set.
Besides neurochemical and neurophysiological factors, there may also be other unexpected contributors to whether or not a person is likely to experience lucid dreams. One big factor could simply diet and nutrition. Denholm Aspy, Ph.D., who researches lucid dreaming claims that “People that are low in certain vitamins […] tend to have poor dream recall and not have lucid dreams at all,”.
However, he also “found that giving people vitamin B-6 supplements caused them to remember more of their dreams, and that could be useful for having lucid dreams as well.”
It is also said (with very little doubt) that lucid dreaming can be ‘learnt’. One of the best-known techniques is “reality testing”. Here, you ask yourself regularly during the day whether you are dreaming, hoping that this will spill into your actual dreams. Mnemonic Induction of Lucid Dreaming (Mild) is yet another technique to master lucid dreaming. Here, every time you wake from a normal dream, you can spend a bit of time identifying the so-called “dream signs”. These include anything that was strange or improbable that separates the dream from your real life.
As you then try to go back to sleep, you visualize entering that dream and intend to recognise that you are dreaming. Some studies suggest that it may also be particularly effective if you set an alarm to wake up after a few hours of sleep and spend a whole hour practicing Mild, before dozing off again. This is called WBTB – Wake Back to Bed.
Additionally, there are also some commercial devices that claim to offer this kind of stimulation. However, most of them have NOT been adequately tested for their efficacy – and hence should be considered with utmost caution.
So, what are the pros and cons of lucid dreaming?
Frequent lucid dreaming has been correlated with sleep fragmentation or shifts to lighter sleep stages or wakefulness. Thus a direct consequence of lucid dreaming is sleep disturbances. Lucid dreaming is a state of consciousness in which the dreamer is aware that they are dreaming. This awareness can restructure the sleeper’s sleep-wake cycle. This may negatively affect a persons’ emotional regulation, memory consolidation, along with other aspects of day-to-day life linked to sleep health.
However, a report published in 2019, stated that it may be claimed that Lucid Dreaming is unlikely to disrupt sleep because most lucid dreamers do not spend much of their sleep-time in lucid dreaming in absolute terms.
Caveat is that induction techniques like the “wake back to bed” technique may be the culprit of disturbing sleep in individuals as it requires deliberate sleep interruption. On a positive note, studies have discovered that lucid dreaming may help reduce nightmares in people with post-traumatic stress disorder (PTSD).
Although not all studies in this subject have replicated this observation, a few have found lucid dreaming can reduce anxiety and depression in people who have both PTSD and nightmares.
Lucid dreaming could pose a risk to people who experience psychosis. Lucid dreaming involves metacognition, a type of self-awareness and understanding of one’s own thought processes from an outside viewpoint. Some researchers point out that this third-person view of one’s self during a lucid dream is analogous to a dissociative mental state. Dissociation can be interpreted as a feeling of being detached from your body and trouble discerning what is real. This is commonly experienced by some people with mental illness, for instance in early psychosis. Preliminary studies suggest that lucid dreaming is linked to psychosis both positively and negatively.
For instance some studies claim that people who have not experienced psychosis ever before, might see a positive impact of lucid dreaming, by becoming stronger psychologically. On the other hand, engaging in lucid dreaming might harm those who have prior experience with psychosis. Lucid dreaming could make their internal reality, here, the dream state seem more like reality, thus disrupting their mental stability.
Besides these, there are a few other interesting applications of lucid dreaming that scientists have researched about. For instance, in a form of lucid dreaming therapy, patients are encouraged to confront, interview, accept and even befriend their dream demons, and this has been claimed to reduce persistent nightmares, which afflict as many as 6 percent of adults at least once a week.
A 2017 study suggested that around 51% of people experience a lucid dream at least once in their life. Around 20% experienced lucid dreamers see a lucid dream, at least once a month. This same study also found that personality traits could affect a person’s likelihood of experiencing lucid dreams. They found that being open to new experiences correlates with a higher frequency of lucid dreaming. This study may have suggested that Lucid Dreaming is not that rare a phenomenon.
Hence, it is important to learn how our brain could get affected or affect our lucid dreaming abilities. It is a neurological phenomenon that could or could not have a drastic impact on your brain and behavior, depending on your prior experiences and personality traits. Although there are some positive impacts of lucid dreaming as well and one can learn how to dream lucidly, one should approach this with caution as there are huge changes that can be observed on ones’ brain – good and bad!