This article will discuss the following points:
- What are dreams and when do they occur?
- How does dreaming differ from being awake?
- What is Lucid Dreaming?
- How have dreams been interpreted so far?
- Why do we forget our dreams?
What are dreams and when do they occur?
A dream is generally characterised as a ‘physiologically and psychologically conscious state that occurs during sleep and is often characterised by a rich array of endogenous sensory, motor, emotional, and other experiences‘ [2].
There are two main stages of sleep, namely the non-rapid eye movement (n-REM) and rapid eye movement (REM) sleep. One of the substages of n-REM sleep is also known as deep sleep, during which heart rate and breathing decrease to the minimum and brain waves are slow [8, 12]. The REM stage is accompanied by rapid eye-movements, heightened brain activity, increased breathing and heart rate, and temporary paralysis of leg and arm muscles [12]. During the night, a person goes through approximately 4-6 sleep cycles, each consisting of the n-REM stage at the beginning and the REM stage towards the end [14].
On average, a person spends around 2 hours dreaming each night [12]. Dreams can occur during the n-REM stage, however, it is less common, and such dreams are thought to be more simple and static. On the other hand, dreaming during the REM stage is much more common and these dreams are thought to be much more vivid [15]. In 1997, researchers Dement and Kleitman [6] conducted an experiment and concluded that the physiological processes accompanying the REM stage are an external manifestation of dreaming. Moreover, the paralysis of muscles during this stage prevents us from acting out our dreams [15].
What is Lucid Dreaming?
A special type of dream is a lucid dream (LD). During lucid dreaming, the person becomes aware of the fact that they are dreaming and might be able to, to some extent, control the content of the dream [4].
A great deal of research advances the use of lucid dreaming as a therapeutic technique for people suffering from Sleep Disorders, recurring nightmares, and PTSD (Post-traumatic Stress Disorder) [16]. At a practical level, LD seems to open the possibility of a re-signification of the dream scene: by knowing that it is only a dream, a person can stop fearing the threat or even confront it, as it could never bring actual physical damage. Subjects have reported that their “monster” seems to fade away with time, reducing the frequency and intensity of intrusive memories. Other explored benefits of LD include mental-flexibility, problem-solving creativity, self-confidence, and this is why it is more and more combined with therapy [16].
So, how can we induce lucid dreaming? Naturally, this question cannot be answered with certainty, but several techniques have been developed. These are mainly a) cognitive methods; b) external stimulations (sound, light, vibrations); c) substance intake (i.e., specific drugs) [17].
Here are three main cognitive techniques that you can try, if you are intrigued by lucid dreaming [19]!
- Dream diary - write down your dreams as soon as you wake up, by specifically focusing on vivid content and particular elements or emotions.
- Wake-up-back-to-bed - choose a night where you can sleep without interruptions and are not busy the morning after. Sleep for around 6 hours, wake up with an alarm, stay up (walk around) for 30 minutes and recall the dream you just had by saying “next time I dream about this, I will be aware that I am dreaming. If you didn’t dream, recall a previous dream. Go back to sleep for another 2-3 hours. Repeat this on different occasions!
- Reality testing/reflection - During the day, ask yourself “am I dreaming or am I awake?” while checking the environment for evidence. This should help transfer the same technique to when you are dreaming, and improve your clarity [19].
Undoubtedly, different researchers report different findings on the effectiveness of these methods. However, there is substantial agreement on the fact that lucid dreaming can be trained and can indeed help those experiencing nightmares.
How does dreaming differ from being awake?
Interestingly, dreams seem to be quite similar to real experiences of wakefulness both at cognitive and neurocognitive levels [18]. First of all, the modalities of perception that are present during wakefulness are represented in most of our dreams making them a true sensory experience and not simple abstractions. Dreams are extremely visual: we can see full color, shapes, and movement. Moreover, dreams present auditory stimuli including speech and conversation. It is instead more rare to perceive tactile or olfactory stimuli but we are able to distinguish between pleasure and pain similar to when we are awake.
These similarities are visible at a neurophysiological level. Brain activity looks remarkably similar during active waking and REM sleep. For example, activation of parts of the visual cortex is present during REM sleep. An interesting finding revealed that patients with brain lesions that impaired their ability to perceive faces in the real world also do not dream of faces [18].
Despite the similarities, what is fascinating about dreams is how they differ from wakefulness.
The major differences between dreaming and wakefulness are:
- Reduced voluntary control and volition - It has happened to many of us that we wake up from an intense dream and state “it was only a dream”. This is usually because we didn’t consciously desire to dream about something. In fact, during dreaming, there is a significant reduction of volition and control of action and thought. In dreams, we seem to be unable to pursue our goals or self-monitor and this can be traced back to the fact that our right inferior parietal cortex, which controls our waking volition, is deactivated during REM sleep.
- Reduced self-awareness and altered reflective thought - While dreaming we are not aware of where we are (in bed) or of what we are doing (sleeping). Dreaming is almost always a delusional experience because we believe that the events and characters are real. Also, our ability to reflect is altered. In dreams we can engage in activities and see things that are essentially impossible i.e., flying, sudden transformations, non-existing objects such as “pink elephants” [18]. Moreover, there are often inconsistencies in terms of space, time, and personal identities. For example, it might have happened to you that a person in a dream may have the name, style, and personality of a friend, but have another person’s face.
- Emotionality - Some dreams have a high degree of emotional involvement. These emotions usually include joy, surprise, anger, fear, and anxiety. Interestingly, however, feelings such as sadness, guilt, envy, low energy are rare. This is perhaps related to the reduced ability to self-reflect [18].
How have dreams been interpreted so far?
So far, there is no clear consensus on the meaning and purpose of dreams. Some researchers suggest that dreams serve no purpose while others developed extensive theories that attempt to explain their meaning.
One of the first to explore the underlying meaning of dreams was surely Sigmund Freud. [9] He referred to dreams as the ‘royal road to the unconscious’ as he believed that they are a result of our repressed, unconscious thoughts and desires. Freud recognised two major components of dreams. The manifest content refers to the actual imagery of dreams that is supposed to symbolically represent the latent content – the underlying psychological aspect of dreams. According to Freud, distinct symbols are associated with specific unconscious conflicts that apply equally to everyone. Thus, to him the purpose of dreaming is to surface repressed desires and to confront them, relieving psychological distress [9].
Freud has been criticised quite a lot in contemporary research due to the lack of empirical evidence behind his theories. However, recent studies show significant support of dreams portraying some personal anxieties, that we are not aware of, but that we are experiencing while awake. For example, it is common for people to dream of being dressed inappropriately, being lost, or late for an exam[18].
Unlike Freud, Carl Jung [3] believed that dreams can be highly personal and that there is no such thing as universal symbols. He believed that dreams should be interpreted in terms of an individual’s personal experiences. He also suggested that dreams can serve a problem-solving function.
Another way of interpreting dreams is to view them through a more cognitive lens. According to Hall, dreams are a part of one’s cognitive process [10] in the sense that they embody one’s thoughts during sleep. He believed that the purpose of dream interpretation is to understand the person, not the dream itself, since people often express the same traits in dreams and while being awake.
How does neuroscience view dreams?
Domhoff [3, 7] presented a more contemporary view postulating that dreams have no real, ultimate purpose. He believed that dreams are simply a result of neuro-cognitive processes and a system of schemas (mental frameworks used to organise information). Hence, to him, dreams are just thoughts that do not necessarily hide any underlying meaning.
Another contemporary view is the activation-synthesis model. This model explains dreaming in terms of electrical brain impulses. J. A. Hobson [3] proposed that our limbic system (brain area responsible for emotions or memories) creates brain impulses and dreams are simply a subjective interpretation of these impulses. In other words, dreams can be seen as the cortex's effort to make sense of random signals given by the limbic system.
Lastly, some other theories of dreams include the idea that dreaming is a way of consolidating memories, regulating emotions, or preparing us for dangerous situations by allowing us to practice survival skills in a safe environment (i.e., dreams) [4].
Why do we forget our dreams?
Sometimes we remember our dreams or fragments of them. Other times we only remember them for a few seconds after waking up and forget them shortly after. Sometimes we do not remember our dreams at all, which leads us to believe that we did not dream during the night. However, this belief is most likely incorrect. There is no clear explanation as to why this happens, however, researchers suggested several contributing factors.
One of these factors is the exact moment when we wake up. Based on their experimental findings from 1957, researchers Dement and Kleitman [6] concluded that we might be more likely to remember our dreams when we wake up from REM sleep rather than the n-REM stage. Indeed, extensive research shows that awakenings from the REM stage lead to dream recall over 80% of the time compared to 50% for n-REM awakenings [13]. Researchers Koulack and Goodenough [11] developed the arousal-retrieval model according to which dream recall can be increased if a person wakes up directly after experiencing the dream, while the dream is still being processed in the short-term memory. Furthermore, we might remember our dreams better if our REM pattern of sleep is fragmented. This means waking up frequently during the REM stage [5, 15]. Another contributing factor might be the emotional content of the dream. Dreams that evoke strong emotions, such as nightmares, might be remembered more easily [15].
To conclude,
Dreaming occurs most frequently during the REM stage of sleep. There is no consensus regarding the purpose or meaning of dreams. Some of the most popular theories include: Freud’s belief that dreams represent our repressed desires; Jung’s proposal that dreams may serve a problem-solving function; Hall’s idea that dreams are expressions of one’s thoughts; Domhoff’s and Hobson’s suggestions that dreams are a result of neuro-cognitive processing. Moreover, the reasons behind the forgetting of dreams are not fully clear, either. Waking up from the REM stage, waking up directly after experiencing the dream and emotional content could increase the likelihood of dream recall. Lastly, lucid dreaming is a new practice that can benefit people who experience frequent nightmares.
So, do you believe that dreams have a meaning? Do you like to analyse your dreams or do you keep a dream journal? Let us know and don’t be shy to share some of the crazy dreams you have had!
Some extra resources:
1. Short article (3-5 minutes): Hobson’s 5 characteristics of dreams https://www.verywellmind.com/characteristics-of-dreams-2795936
2. Youtube video: Guide to lucid dreaming https://www.youtube.com/watch?v=zhblGWWVk-M
3. Youtube video: ‘I learned how to lucid dream’ https://www.youtube.com/watch?v=B8yJeNa-bPU
References
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2. APA Dictionary of Psychology. Dream. Retrieved February 14, 2021, from https://dictionary.apa.org/dream
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11. Koulack, D., & Goodenough, D. R. (1976). Dream recall and dream recall failure: An arousal-retrieval model. Psychological Bulletin, 83(5), 975–984. https://doi.org/10.1037/0033-2909.83.5.975
12. National Institute of Neurological Disorders and Stroke (August 2019). Brain Basics: Understanding Sleep. Retrieved February 14, 2021, from https://www.ninds.nih.gov/Disorders/Patient-Caregiver-Education/Understanding-sleep#2
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16. de Macêdo, T. C. F., Ferreira, G. H., de Almondes, K. M., Kirov, R., & Mota-Rolim, S. A. (2019). My dream, my rules: can lucid dreaming treat nightmares?. Frontiers in psychology, 10, 2618. https://doi.org/10.3389/fpsyg.2019.02618
17. Stumbrys, T., Erlacher, D., Schädlich, M., & Schredl, M. (2012). Induction of lucid dreams: A systematic review of evidence. Consciousness and Cognition, 21(3), 1456-1475. https://doi.org/10.1016/j.concog.2012.07.003
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19. Dyck, S., Schredl, M., & Kühnel, A. (2017). Lucid dream induction using three different cognitive methods. International Journal of Dream Research. https://doi.org/10.11588/ijodr.2017.2.37498