The consequences of nightmares
Alexandre Lemyre, M.A., Ph.D.
The content of this article was last updated on February 1, 2022.
Introduction
If you have experienced frequent nightmares, or if you know someone who has, you are probably aware that waking up is not the end of the story. In addition to being extremely unpleasant, nightmares can impact sleep, mood, and several other aspects of life. Just like insomnia or sleep apnea, nightmares can be highly debilitating, especially when they are frequent. Throughout my doctoral studies, I have conducted several research on dreaming. The experience of nightmares is one of the topics I find most fascinating. I believe it is important to understand the consequences of nightmares in order to grasp the importance of this sleep problem. In this post, I will summarize the state of the scientific literature on the consequences of nightmares.
Nightmare consequences can take many forms
The combination of all the nightmare consequences that an individual experience is called nightmare distress. Three questionnaires have been developed specifically to measure nightmare distress: the Nightmare Effects Survey (Krakow et al., 2000; Martínez et al., 2005), the Van Dream Anxiety Scale (Ağargün et al., 1999), and the Nightmare Distress Questionnaire (Belicki, 1992; Böckermann et al., 2014; Martínez et al., 2005). Here is a short description of each of these three questionnaires.
The Nightmare Effect Survey (Krakow et al., 2000) covers every aspect of life that can potentially be affected by nightmares. More precisely, the scale contains 11 items, with each item evaluating a specific nightmare consequence. Each of these items is written in the same format: “Please rate how much your *XYZ* is adversely or negatively affected by nightmares”. The only thing that changes between the 11 items is *XYZ*, which is replaced by “sleep”, “work”, “relationship”, “daytime energy”, “school”, “mood”, “sex life”, “diet”, “mental health”, “physical health”, and “leasure and activities”. Overall, this scale does not tell us anything specific about the consequences of nightmares, other than the fact that nightmares can impact almost every aspect of life.
According to Ağargün et al. (1999), the Van Dream Anxiety Scale was developed based on several sources: “clinical experiences with nightmare disorder patients; a metanalysis of literature on dream research; and a review of dream recall studies.” (p.205). This scale assesses the following consequences in relation to nightmares: (a) a difficulty falling asleep after a nightmare, (b) being afraid of sleeping because of a frightening dream, (c) having trouble sleeping, (d) physiological symptoms associated with nightmares (e.g., shortness of breath, dizziness, palpitation, sweating), (e) feeling sleepy because of nightmares, (f) being irritated or anxious because of nightmare, (g) altered functioning in different areas of life, namely work, relationships, and social activities, (h) disturbance in one’s mood or psychological status, (i) and a difficulty concentrating.
The Nightmare Distress Questionnaire was developed by Belicki (1992). Unfortunately, Belicki (1992) did not specify how the questionnaire’ items were constructed. Although she is a credible sleep expert, this lack of information casts some doubt on the questionnaire’s ability to adequately measure the consequences of nightmares. Despite this fact and the old age of this questionnaire, it is still one of the most frequently used questionnaires to evaluate nightmare distress in treatment studies (Augedal et al., 2013), which I believe is an example of “old habits die hard” in the field of psychology. According to a psychometric study (Böckermann et al., 2014) – that is, a study that analyzes the properties and the structure of a questionnaire –, the items from the Nightmare Distress Questionnaire can be divided into three categories. The first category assesses general nightmare distress and contains generic items, such as “Do you feel you have a problem with nightmares?” The second category assesses the impact of nightmares on sleep: (a) having difficulty to put a nightmare out of one’s mind after awakening from it, (b) being afraid to fall asleep, and (c) having difficulty to fall back asleep after a nightmare. The third category assesses the impact of nightmares on daily perceptions: (e) avoiding or disliking someone because that person (more precisely, a representation of that person) was encountered in a nightmare, (f) having the feeling that something that happened in the nightmare actually occurred in reality, (g) being anxious that the nightmare predicts the future, and (h) having a difficulty to convince oneself that the nightmare is “just a dream” because it felt too real.
Together, the Van Dream Anxiety Scale and the Nightmare Distress Questionnaire cover most of the possible consequences of nightmares. Now, you might be a bit disappointed not knowing how common these consequences are. Unfortunately, the studies that used these two questionnaires do not provide this information. Luckily for us, there exist a fourth nightmare distress questionnaire that might give us just what we are looking for.
Some consequences of nightmares are more common than others
The Nightmare Behavior Questionnaire was developed by Köthe and Pietrowsky (2001) and improved by Pietrowsky and Köthe (2003). While the questionnaires presented in the previous section assess the consequences that nightmares have in general, the Nightmare Behavior Questionnaire assesses the consequences of nightmare(s) on a given day. Thus, this questionnaire can only be completed on a day following a night with nightmare(s). It contains 43 items, about half of which measure the physiological, emotional, and cognitive consequences of nightmares.
In latest study that used the Nightmare Behavior Questionnaire (Pietrowsky & Köthe, 2003), 30 individuals with frequent nightmares (at least 12 in the past year) completed the questionnaire on each day where they experienced a nightmare, for a period of four weeks. Together, these participants reported 104 nights with nightmares during the four-week period, which means that the questionnaire was completed 104 times. The following is the percentage of nights with nightmares (out of 104 nights) that produced each of the consequences.
- Feeling relieved that it was only a dream (66%)
- Being preoccupied with the memory of the nightmare (53%)
- Having compulsive memories about the nightmare (39%)
- Brooding about persons or objects that were in the nightmare (36%)
- Perceiving the nightmare as an indication that something is wrong with one’s own life (36%)
- Feeling distressed (26%)
- Feeling frightened after awakening (25%)
- Feeling discouraged after the nightmare (23%)
- Being worried that “something is wrong with me” (23%)
- Accelerated heart rate (21%)
- Feeling nervous and restless (18%)
- Mood being strongly influenced by the nightmare (18%)
- Sweating (13%)
- Being afraid that the nightmare becomes true (13%)
- Feeling disgust (11%)
- Feeling guilty of dreaming such things (10%)
- Being afraid that the nightmare tells something terrible about oneself (9%)
- Shivering (8%)
- Nausea (7%)
Nightmares can impact emotions in various ways
Using questionnaires is not the only way to evaluate the consequences of nightmares. In our own study (Lemyre, St-Onge, et al., 2019), we used a different approach. More precisely, I interviewed 20 university students who experienced a nightmare problem ranging from mild to severe (i.e. several times per week for several months). As part of the interview, I asked the participants to talk about the consequences of their nightmares. We then used the interviews recording to categorize the consequences that had been reported by the participants.
My favorite finding from our study pertains to the different ways in which nightmares can influence emotions in waking, which I describe below.
(1) The simplest way in which dream emotions can influence waking emotions is through a priming effect. That is, the emotions experienced in dreams appear to stick on upon awakening and during the day. In principle, this would not apply to nightmares, but to all dreams, assuming that the dream emotions were strong enough. As a concrete example, in one study (Selterman et al., 2014), among individuals who were in couple relationship, those who had experienced jealousy in a dream involving their partner were more likely to have conflict in their relationship on the following day. One explanation proposed by the authors of this study is that the emotion of jealousy remained primed the next day, which could have tilted behaviors toward conflicts (Selterman et al., 2014).
(2) The individual can experience fear or other negative emotions toward a person or an object that was encountered in the nightmare (of course, it is not really the person that was encountered in the dream, but rather a mental representation of that person). For instance, if a person is criticized by their boss in their dream, they might experience anxiety the following morning when encountering their boss in real life. The mechanisms behind this consequence have not been studied, but I believe that it could be due to fear conditioning in dreams.
(3) Sometimes, it is not the nightmare per se that produces negative emotions in waking, but rather the painful memories that it brings back. This can be the case with posttraumatic nightmares, where the nightmare contains elements of a past trauma.
(4) Some individuals may consider themselves accountable for having a nightmare, or for the actions that were made in the nightmare. This can result in feelings of guilt or shame in waking. In that regard, researchers have highlighted that voluntary control over attention and behaviors is impaired during dreaming (Nir & Tononi, 2010; Windt, 2007), which means that the actions that are performed in nightmares are unlikely to be a truthful reflection of the actions that would be performed in a similar situation in waking. Also, thought processes are altered in various ways during dreaming (Kahn & Hobson, 2005; Revonsuo, 2005; Schwartz & Maquet, 2002), which means that the dreamer is likely ill-equipped to make proper decisions, especially in the presence of strong negative emotions. In conclusion, the guilt/shame that a person feels in relation to actions that were performed in a nightmare is likely unjustified (long story short, you do not have to feel bad about it).
(5) Some individuals tend to ask themselves, “what if the events of the nightmare happened in reality?” For instance, if someone dreams about the death of a relative, they might ask themselves how they would feel if they faced this person’s death in reality. These thoughts might in turn generate negative emotions.
(6) Nightmares can reduce sleep quality, in addition to produce awakenings that are often followed by a difficulty falling back asleep. This is unfortunate, since having a bad sleep tends to increase emotional reactivity to distressing events (Deliens et al., 2014; Walker, 2009). As a consequence, nights with nightmares are often followed by fatigue and increased irritability (feeling on the edge). It is also worth noting that fatigue sometimes interfered with concentration or the ability to take part in social or professional activities.
(7) In some cases, nightmares with repetitive themes can negatively impact self-perception. For instance, dreaming of being repeatedly rejected, or being incapable of performing certain tasks, may bring about a feeling of unworthiness or incompetency in waking.
Nightmares are linked to suicidal behaviors
Based on converging evidence from several studies, frequent nightmares – especially when they persist over an extended period of time – tend to increase the risk of suicidal ideation and behaviors, and this effect cannot be solely explained by a higher degree of anxiety or depressive symptoms (Titus et al., 2018, reviewed studies on this topic). Similarly, individuals who experience a depression and nightmares present a greater risk for suicide than individuals who experience a depression without nightmares (based on a review by Wang et al., 2019). Generally speaking, among individuals with a mental disorder, those who experience nightmares tend to struggle more with their mental health (Lemyre, Bastien, et al., 2019). As always, it is important to be careful when analyzing the results of correlational studies: correlation does necessarily mean causation. Nonetheless, these results point toward a possible role of nightmares in increasing the risk for suicide and in aggravating mental health problems.
Summary and Conclusion
For most people, experiencing a nightmare is a rare occurrence. They might feel upside down and a bit tired the next day, but the following night will bring about the welcome rest that they need to start anew and go on with their lives. However, for people who experience nightmares weekly, sometimes several times per week, this nocturnal experience can pervade every area of daily life, from moods and well-being, to relationships, to functioning at work. It sometimes feels like there is still a stigma around nightmares, as it should not be considered a real difficulty. This stigma has no ground in reality. According to the American Psychiatric Association (2013), chronic nightmares can constitute a mental health disorder when they cause significant distress and/or impairments in major areas of functioning (e.g., work, study, family, etc.)
As always, there is light in darkness. If you are struggling with chronic nightmares, there exist effective psychological treatments for this difficulty (Aurora et al., 2010; Morgenthaler et al., 2018). The best way to find professional help for this difficulty is to contact a certified psychologist. In particular, you are encouraged to seek help from psychologists who work in sleep clinics, as they are the most familiar with nightmare treatments. Beside psychological treatments, medication is also an option. If you choose this avenue, you can contact a general practitioner.
References
Ağargün, M. Y., Kara, H., Bilici, M., Çilli, A. S., Telci, M., Semiz, Ü. B., & Başoğlu, C. (1999). The Van Dream Anxiety Scale: A subjective measure of dream anxiety in nightmare sufferers. Sleep and Hypnosis, 1(4), 204-211.
American Psychiatric Association. (2013). Diagnostic and statistical manual of mental disorders (5th ed.). Author.
Augedal, A. W., Hansen, K. S., Kronhaug, C. R., Harvey, A. G., & Pallesen, S. (2013). Randomized controlled trials of psychological and pharmacological treatments for nightmares: A meta-analysis. Sleep Medicine Reviews, 17(2), 143-152. https://doi.org/10.1016/j.smrv.2012.06.001
Aurora, N. R., Zak, R. S., Auerbach, S. H., Casey, K. R., Chowdhuri, S., Karippot, A., Maganti, R. K., Ramar, K., Kristo, D. A., Bista, S. R., & Lamm, C. I. (2010). Best practice guide for the treatment of nightmare disorder in adults. Journal of Clinical Sleep Medicine, 6(04), 389-401. https://doi.org/10.5664/jcsm.27883
Belicki, K. (1992). The relationship of nightmare frequency to nightmare suffering with implications for treatment and research. Dreaming, 2(3), 143-148. https://doi.org/10.1037/h0094355
Böckermann, M., Gieselmann, A., & Pietrowsky, R. (2014). What does nightmare distress mean? Factorial structure and psychometric properties of the Nightmare Distress Questionnaire (NDQ). Dreaming, 24(4), 279.
Deliens, G., Gilson, M., & Peigneux, P. (2014). Sleep and the processing of emotions. Experimental Brain Research, 232(5), 1403-1414. https://doi.org/10.1007/s00221-014-3832-1
Kahn, D., & Hobson, J. A. (2005). State-dependent thinking: A comparison of waking and dreaming thought. Consciousness and Cognition, 14(3), 429-438. https://doi.org/10.1016/j.concog.2004.10.005
Köthe, M., & Pietrowsky, R. (2001). Behavioral effects of nightmares and their correlations to personality patterns. Dreaming, 11(1), 43-52. https://doi.org/10.1023/A:1009468517557
Krakow, B., Hollifield, M., Schrader, R., Koss, M., Tandberg, D., Lauriello, J., McBride, L., Warner, T. D., Cheng, D., Edmond, T., & Kellner, R. (2000). A controlled study of imagery rehearsal for chronic nightmares in sexual assault survivors with PTSD: A preliminary report. Journal of Traumatic Stress, 13(4), 589-609. https://doi.org/10.1023/A:1007854015481
Lemyre, A., Bastien, C., & Vallières, A. (2019). Nightmares in mental disorders: A review. Dreaming, 29(2), 144-166. https://doi.org/10.1037/drm0000103
Lemyre, A., St-Onge, M., & Vallières, A. (2019). The perceptions of nightmare sufferers regarding the functions, causes, and consequences of their nightmares, and their coping strategies. International Journal of Dream Research, 35-48. https://doi.org/10.11588/ijodr.2019.2.62396
Martínez, M. P., Miró, E., & Arriaza, R. (2005). Evaluation of the distress and effects caused by nightmares: A study of the psychometric properties of the nightmare distress questionnaire and the Nightmare Effects Survey. Sleep and Hypnosis, 7(1), 29-41.
Morgenthaler, T. I., Auerbach, S., Casey, K. R., Kristo, D., Maganti, R., Ramar, K., Zak, R., & Kartje, R. (2018). Position paper for the treatment of nightmare disorder in adults: An American Academy of Sleep Medicine position paper. Journal of Clinical Sleep Medicine, 14(6), 1041-1055. https://doi.org/10.5664/jcsm.7178
Nir, Y., & Tononi, G. (2010). Dreaming and the brain: From phenomenology to neurophysiology. Trends in cognitive sciences, 14(2), 88-100. https://doi.org/10.1016/j.tics.2009.12.001
Pietrowsky, R., & Köthe, M. (2003). Personal boundaries and nightmare consequences in frequent nightmare sufferers. Dreaming, 13(4), 245-254. https://doi.org/10.1023/B:DREM.0000003146.11946.4c
Revonsuo, A. (2005). The Self in Dreams. In T. E. Feinberg & J. P. Keenan (Eds.), The lost self: Pathologies of the brain and identity. (pp. 206-219). Oxford University Press. https://doi.org/10.1093/acprof:oso/9780195173413.003.0014
Schwartz, S., & Maquet, P. (2002). Sleep imaging and the neuropsychological assessment of dreams. Trends in cognitive sciences, 6(1), 23-30. https://doi.org/10.1016/s1364-6613(00)01818-0
Selterman, D. F., Apetroaia, A. I., Riela, S., & Aron, A. (2014). Dreaming of you: Behavior and emotion in dreams of significant others predict subsequent relational behavior. Social Psychological and Personality Science, 5(1), 111-118. https://doi.org/10.1177/1948550613486678
Titus, C. E., Speed, K. J., Cartwright, P. M., Drapeau, C. W., Heo, Y., & Nadorff, M. R. (2018). What role do nightmares play in suicide? A brief exploration. Current opinion in psychology, 22, 59-62.
Walker, M. P. (2009). The role of sleep in cognition and emotion. Annals of the New York Academy of Sciences, 1156(1), 168-197. https://doi.org/10.1111/j.1749-6632.2009.04416.x
Wang, X., Cheng, S., & Xu, H. (2019). Systematic review and meta-analysis of the relationship between sleep disorders and suicidal behaviour in patients with depression. BMC Psychiatry, 19(1), 1-13. https://doi.org/10.1186/s12888-019-2302-5
Windt, J. M. (2007). The philosophy of dreaming and self-consciousness: What happens to the experiential subject during the dream state? In D. Barrett & P. McNamara (Eds.), The new science of dreaming: Volume 3 (pp. 193-248). Praeger Publishers.
