Having the same dream over and over is a well-known phenomenon: almost two-thirds of the population say they have recurring dreams.
Being chased, finding yourself naked in a public place or in the middle of a natural disaster, losing your teeth or forgetting to go to class for an entire semester are typical recurring scenarios in these dreams.
But where does the phenomenon come from?
Science has shown that recurring dreams could reflect unresolved conflicts in the life of the dreamer.
Recurring dreams often occur during times of stress or for long periods of time, sometimes several years or even a lifetime.
These dreams not only share the same themes, they can also repeat the same narrative night after night.
Although the exact content of recurring dreams is unique to each person, there are common themes between individuals and even between cultures and in different periods.
For example, being chased, falling, not being prepared for an exam, being late, or repeatedly trying to do something are among the most frequent scenarios.
Most recurring dreams have a negative content that involves emotions like fear, sadness, anger and guilt.
More than half of recurring dreams involve a situation in which the dreamer is in danger.
But some recurring themes can also be positive, even euphoric, such as dreams where we discover new rooms in our house, erotic dreams or where we fly.
In some cases, recurring dreams that begin in childhood can persist into adulthood.
These dreams can disappear for a few years, reappear in the presence of a new source of stress, and then disappear again when the situation is over.
Why does our brain reproduce the same dreams over and over again?
Studies suggest that dreams, in general, help us regulate our emotions and adapt to stressful events.
Incorporating emotional material in dreams can allow the dreamer to process a painful or difficult event.
In the case of recurring dreams, the repetitive content could represent a failed attempt to integrate these difficult experiences.
Many theories agree that recurring dreams are related to unresolved difficulties or conflicts in the dreamer’s life.
Having recurring dreams has also been associated with lower levels of psychological well-being and the presence of symptoms of anxiety and depression.
These dreams tend to recur during stressful situations and they stop when the person has resolved their personal conflict, indicating better well-being.
Recurring dreams often metaphorically reflect the emotional concerns of the dreamers.
For example, dreaming of a tsunami is common after trauma or abuse. This is a typical example of a metaphor that can represent emotions of helplessness, panic, or fear experienced in waking life.
The nightmare of being naked
Similarly, being inappropriately dressed in a dream, being naked, or not being able to find a bathroom can represent scenarios of embarrassment or modesty.
These themes can be thought of as scripts that provide us with a space where we can digest our conflicting emotions.
The same script can be reused in different situations where we experience similar emotions.
That is why some people, when faced with a stressful situation or a new challenge, may dream that they show up unprepared for a math test, even years after they have set foot in school.
Although the circumstances are different, a similar feeling of stress or desire to excel can trigger the same dream scenario again.
A continuum of repetitions
William Domhoff, American researcher and psychologist, proposes the concept of a continuum of repetitions in dreams.
At one extreme, traumatic nightmares directly reproduce a lived trauma. This is one of the main symptoms of PTSD.
Then there are the recurring dreams in which the same dream content is reproduced in part or in full.
Unlike traumatic dreams, recurring dreams rarely reproduce an event or conflict directly, but rather reflect it metaphorically through a central emotion.
Further down the continuum are recurring themes in dreams.
These dreams tend to reproduce a similar situation, such as being late, being chased, or getting lost, but the exact content of the dream differs from moment to moment, such as being late for a train rather than an exam.
Finally, at the other end of the continuum, we find certain dream elements that are repeated in an individual’s dreams, such as characters, actions or objects.
All these dreams would reflect, at different levels, an attempt to resolve certain emotional concerns.
Going from an intense level to a lower level on the repetition continuum is often a sign that a person’s psychological state is improving.
For example, in the content of traumatic nightmares progressive and positive changes are often observed in people who have experienced trauma as they gradually overcome their difficulties.
Why do topics tend to be the same from person to person? One possible explanation is that some of these scripts have been preserved in humans due to the evolutionary advantage which provide.
By simulating a threatening situation, the dream of being chased, for example, provides a space for a person to practice perceiving and escaping from predators while sleeping.
Some common themes can also be explained, in part, by physiological phenomena that take place during sleep.
A 2018 study by a research team in Israel found that dreaming of losing teeth was not particularly related to anxiety symptoms, but rather to clenching your teeth during sleep or dental discomfort upon waking.
When we sleep, our brain is not completely isolated from the outside world. Continue to perceive external stimuli, such as sounds or smells, or internal body sensations.
That means other issues, like not being able to find a bathroom or being naked in a public space, could actually be driven by the urge to urinate at night or wearing loose pajamas.
Some specific physical phenomena of REM sleep – the stage of sleep in which we dream the most – could also be at play.
In REM sleep, our muscles are paralyzed, which It could lead to dreams of having heavy legs or being paralyzed in bed.
Likewise, some authors have proposed that dreams of falling or flying are caused by our vestibular system, which contributes to balance and can be spontaneously reactivated during REM sleep.
Of course, these sensations are not enough to explain the recurrence of these dreams in some people and their sudden appearance in times of stress, but they probably play an important role in the construction of our most typical dreams.
Break the cycle
People experiencing a recurring nightmare they have jammed somehow in a particular way of responding to the dream scenario and anticipating it.
Therapies have been developed to try to resolve this recurrence and break the vicious cycle of nightmares.
One technique is to visualize the nightmare while awake and then rewrite it, that is, modify the narrative by changing one aspect, for example, the end of the dream, replacing it with something more positive.
The lucid dreaming they can also be a solution.
In lucid dreams we realize that we are dreaming and sometimes we can influence the content of the dream.
Lucidity in a recurring dream could allow us to think or react differently to the dream and thus alter the repetitive nature of the dream.
Nevertheless, not all recurring dreams are bad in themselves. Even Can be useful insofar as they inform us about our personal conflicts.
Paying attention to the repetitive elements of dreams could be a way to better understand and resolve our greatest desires and torments.
* Claudia Picard-Deland is a PhD candidate in neuroscience and Tore Nielsen is Professor of Psychiatry, both at the University of Montreal, Canada. This note originally appeared on The Conversation and is published here under a Creative Commons license.
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