Nightmares are vivid and often disturbing dreams that jolt us awake from our slumber. Though frightening, nightmares are a normal part of rapid eye movement (REM) sleep and are especially common in children. But what do bad dreams say about the quality of your sleep? Here’s what you need to know about nightmares and what they mean for sleep.
What are nightmares?
Nightmares are dreams that bring out strong feelings of fear, terror, distress or anxiety. They tend to occur most often during rapid eye movement (REM) sleep, when dreaming is most common. Though the exact content varies from person to person, nightmares often involve threats to survival, security or self-esteem.
Nightmares can jolt you awake and make it difficult to get back to sleep. You may recall vivid details from the dream upon waking. Nightmares are most prevalent in childhood, with over 50% of kids experiencing bad dreams that disturb their sleep on occasion. They tend to decrease with age but still affect a sizable minority of adults.
Do nightmares interrupt sleep?
Nightmares can definitely interrupt your sleep, especially if they cause you to fully wake up during the night. Research shows that nightmares increase awakings after sleep onset. This can reduce total sleep time and leave you feeling unrested the next day.
However, some nightmares occur during REM sleep but do not actually wake you up. REM sleep is characterized by muscle paralysis, meaning you are unable to move or react physically to the nightmare. These nightmares may not impair your sleep as much since you remain asleep during and after them.
Nightmares are most disruptive if they repeatedly wake you up during the night. Being jolted awake by disturbing dreams night after night can take a toll on the quality and restfulness of your sleep.
Are frequent nightmares a sleep disorder?
Occasional nightmares are normal and often triggered by stress, anxiety or trauma. But in some cases, chronic nightmares can be a sign of an underlying sleep disorder or other medical issue.
Nightmare disorder involves frequent nightmares that cause distress and impairment in daytime functioning. To be diagnosed with nightmare disorder, the frightening dreams must occur at least once a week for several months. Nightmare disorder is relatively rare, affecting just 2-8% of adults.
Other disorders associated with frequent nightmares include:
- Post-traumatic stress disorder (PTSD)
- Sleep apnea
- Restless leg syndrome
- Narcolepsy
- Certain medications
- Substance withdrawal
If you experience persistent, disturbing dreams that negatively impact your sleep and daytime performance, discuss it with your doctor. They can check for underlying conditions and help you get relief from recurrent nightmares.
Do nightmares indicate good sleep and dreaming?
Though unpleasant, nightmares are often viewed as a sign that you are getting good dream sleep. This is because nightmares tend to occur during longer REM cycles in the early morning hours.
REM sleep is crucial for restorative sleep, emotional regulation, memory consolidation and dreaming. Getting sufficient REM sleep means you are progressing through the normal sleep stages. If you rarely dream or have nightmares, it could signal inadequate REM sleep.
However, keep in mind that you can get too much REM sleep. Excessive REM is linked to poor sleep quality and increased nightmares. The optimal amount of REM is 20-25% of total sleep time.
Stage REM sleep and nightmares
During a normal night’s sleep, you progress through cycles of non-REM sleep (stages 1-3) followed by short REM periods. The first REM cycle is around 10 minutes. REM periods get progressively longer with each cycle.
Since REM occurs more frequently and for longer in the second half of sleep, most vivid dreams and nightmares develop during the early morning hours.
Individual REM cycles can last up to an hour before the end of your sleep period. This explains why you may wake up from an intense nightmare right before your alarm goes off.
Poor sleep quality and nightmares
Frequent nightmares can sometimes indicate poor sleep quality. For example, sleep apnea sufferers often experience nightmares due to the constant sleep interruptions. This also applies if you have frequent awakenings due to pain, coughing, or needing to use the bathroom.
Too little REM sleep can also increase the incidence of nightmares. This may occur if you are sleep deprived or consume alcohol before bed, as both disrupt normal REM cycles.
On the flip side, getting too much REM sleep can make nightmares more likely. This is because more time in REM provides increased opportunity for vivid dreaming.
Tips for preventing nightmares
While occasional nightmares are normal, chronic bad dreams can impair your sleep. Here are some tips to help prevent disturbing dreams:
- Reduce stress through relaxation techniques.
- Avoid heavy meals, alcohol and caffeine before bed.
- Establish a regular sleep-wake schedule.
- Limit screen time before bed.
- Clear your mind by writing down worries.
- imagery/visualization.
- Use a sound conditioner to block disruptive noises.
- Try counseling to address trauma or recurring themes.
Practicing good sleep hygiene helps minimize nightmares by promoting consistent, high-quality sleep. If troublesome dreams persist, consider consulting your doctor or a sleep specialist.
Conclusion
Nightmares are common bad dreams that provoke anxiety and fear. Though disturbing, having occasional nightmares can be a sign of healthy REM sleep. However, chronic nightmares may indicate poor sleep or an underlying sleep disorder.
Frequent nightmares disrupt sleep by awakening you during the night. This can reduce sleep time and impair daytime functioning. While you may not be able to fully prevent nightmares, certain lifestyle changes can help set the stage for peaceful dreaming.