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The relationship between bad dreams and sleep quality is complex and multifaceted. While bad dreams, including nightmares, are associated with subjective reports of poorer sleep quality and increased psychological distress, objective measures of sleep architecture do not always reflect these impairments. The emotional content of dreams, the presence of psychological distress, and external factors such as collective trauma all play a role in influencing sleep quality. Further research is needed to fully understand the mechanisms underlying the impact of bad dreams on sleep and to develop effective interventions for improving sleep quality in individuals affected by frequent nightmares.
Sleep is a fundamental aspect of human health, influencing both physical and mental well-being. However, the quality of sleep can be significantly impacted by various factors, including the nature of dreams experienced during sleep. Bad dreams, including nightmares, are commonly reported phenomena that can disrupt sleep and affect overall sleep quality. This article explores the relationship between bad dreams and sleep quality, drawing on findings from multiple research studies.
The Impact of Bad Dreams on Sleep Quality
Emotional Regulation and Sleep Quality
Research has shown that there is a discontinuity between wakefulness and dreaming, with positive emotions being more prevalent during wakefulness and negative emotions during sleep. Poor sleepers, identified through the Pittsburgh Sleep Quality Index (PSQI), exhibit a different pattern of emotionality compared to good sleepers. Poor sleepers show evenly distributed emotional valence across wakefulness and dreaming, suggesting an impairment in sleep-related processes of affect regulation1.
Subjective Sleep Quality and Nightmares
Nightmares are often associated with sleep problems such as prolonged sleep latencies, poorer sleep quality, and daytime sleepiness. A study involving individuals with frequent nightmares reported worse subjective sleep quality, more waking problems, and more severe insomnia compared to healthy controls. However, objective sleep measures obtained through polysomnographic recordings did not show significant differences in sleep architecture between the two groups, indicating that the perceived impairment in sleep quality due to nightmares is not always reflected in physiological indices2.
Sleep Architecture and Nightmares
Nightmares are intense, emotionally negative experiences that typically occur during late-night sleep and result in abrupt awakenings. Polysomnographic studies have shown that individuals with frequent nightmares exhibit impaired sleep architecture, characterized by reduced sleep efficiency, increased wakefulness, reduced slow-wave sleep, and increased nocturnal awakenings. These alterations in sleep architecture are independent of waking psychopathology but are mediated by heightened negative affect during REM sleep4.
Psychological Distress and Sleep Experiences
Unusual nocturnal consciousness phenomena, including nightmares, are strongly related to psychological distress. These experiences, which reflect involuntary intrusions of wakefulness into sleep, may result in aroused sleep and poor sleep quality. The exploration of the interplay between psychopathology and sleep should include qualitative conscious experiences, as they provide rich information on night-time emotional states and broaden the definition of poor sleep quality3.
Lucid Dreaming and Sleep Quality
Lucid dreams, where the dreamer is aware of dreaming, have been speculated to interfere with the restorative function of sleep due to heightened cortical activation. Studies have found a significant relationship between lucid dream frequency and poor sleep quality, which disappears when nightmare frequency is controlled. This suggests that the presence of nightmares, rather than lucid dreaming itself, may contribute to poorer sleep quality6.
Collective Trauma and Dream Content
The COVID-19 pandemic has had a profound impact on dream content and sleep quality. A study on the dreams of Italian participants during the pandemic identified three macro-categories of dream content: phobic content, persecutory themes, and “old normal” dreams. The prolonged quarantine and lifestyle changes during the pandemic have influenced dream activities and contributed to sleep-related difficulties such as problems falling asleep and mild clinical sleep disorders7.
Do bad dreams affect sleep quality?
Jarno Tuominen has answered Uncertain
An expert from University of Turku in Psychology, Neuroscience, Cognitive Science, Behavioural Science
While it appears bad dreams or nightmares don’t affect objective sleep quality (sleep architecture) as such, they are often reported to affect subjective – or felt – sleep quality. This means that even if the physiological structure and attributes of sleep remain relatively unchanged, people do report to have slept worse following bad dreams.
Do bad dreams affect sleep quality?
Sue Llewellyn has answered Uncertain
An expert from University of Manchester in Sleep Research
Sleep quality reflects: time to fall asleep after getting into bed; % of time asleep while in bed; and number of awakenings from sleep. If you fall asleep immediately after getting into bed, stay asleep for 100% of your time in bed and don’t awaken at all then your sleep quality would be 100%, assuming you are asleep for a normal period of time- usually between 7-9 hours each night.
Bad dreams will reduce your sleep quality if they wake you up. After an abrupt awakening, you generally have a strong recollection of the negative content, which is usually fear-inducing. This is likely to keep you awake for a while as you mull over the dream and try to recover from any physical effects- like a rapid heartbeat. Such bad dreams are deemed nightmares.
On the other hand, if your bad dreams aren’t bad enough to wake you up they may improve your sleep quality. Here’s how. You have probably noticed that “things get better over time”. Bad experiences aren’t as distressing after some time has passed. Immediately after a bad incident you will react to it, maybe you will take longer to get to sleep, wake up thinking about the event and ruminate on it while awake. All of this makes you feel bad. Dreaming about negative experiences – when they are associated in the dream with other life events and integrated into memory networks in the brain- reduces this reactivity. Dreams are a form of therapy. You can think about making these dream associations as accepting that the bad experience is somehow similar to previous negative life events, from which you recovered and may even have learnt. So, after a series of dreams, you can remember a bad experience and may have gained some knowledge from it but it doesn’t feel as bad. Nightmares may result from a uniquely bad experience, for example, something life-threatening, which resists association with prior events.
So nightmares will reduce sleep quality but ordinary bad dreams may enhance it!
Do bad dreams affect sleep quality?
Péter Simor has answered Likely
An expert from Eötvös Loránd University Budapest in Sleep Research, Neuroscience, Neuropsychology
There are very few studies that examined directly the effect of bad dreams on sleep quality, but frequent nightmares (bad dreams that end with abrupt awakenings) and bad dreams (that do not provoke awakenings) are associated with poor subjective sleep quality. Moreover, clinical interventions targeting nightmares seem to improve subjective sleep quality beyond ameliorating disturbed dreaming. Although, we do not have enough empirical data on the influence of bad dreams on objective sleep parameters, some studies indicate that frequent nightmares are linked to processes of hiperarousal, that is, individuals having frequent nightmares appear to show more aroused, alert patterns of sleep. On the other hand, with respect to casuality, we still arrive to a chicken and egg problem here: is hyperarousal affecting the quality of dreams, or the other way around?