Nightmares refer to complex dreams that cause high levels of anxiety or terror. In general, the content of nightmares revolves around imminent harm being caused to the individual (e.g., being chased, threatened, injured, etc.). When nightmares occur as a part of posttraumatic stress disorder (PTSD), they tend to involve the original threatening or horrifying set of circumstances that was involved during the traumatic event.
For example, someone who was in the Twin Towers on Sept. 11, 2001, might experience frightening dreams about terrorists, airplane crashes, collapsing buildings, fires, people jumping from buildings, etc. A rape survivor might experience disturbing dreams about the rape itself or some aspect of the experience that was particularly frightening (e.g., being held at knifepoint).
Nightmares can occur multiple times in a given night, or one might experience them very rarely. Individuals may experience the same dream repeatedly, or they may experience different dreams with a similar theme. When individuals awaken from nightmares, they can typically remember them in detail. Upon awakening from a nightmare, individuals typically report feelings of alertness, fear, and anxiety.
Nightmares occur almost exclusively during rapid eye movement (REM) sleep. Although REM sleep occurs on and off throughout the night, REM sleep periods become longer and dreaming tends to become more intense in the second half of the night. As a result, nightmares are more likely to occur during this time.
The prevalence of nightmares varies by age group and by gender. Nightmares are reportedly first experienced between the ages of 3 and 6 years. From 10% to 50% of children between the ages of 3 and 5 have nightmares that are severe enough to cause their parents concern. This does not mean that children with nightmares necessarily have a psychological disorder.
In fact, children who develop nightmares in the absence of traumatic events typically grow out of them as they get older. Approximately 50% of adults report having at least an occasional nightmare. Estimates suggest that between 6.9% and 8.1% of the adult population suffer from chronic nightmares.
Women report having nightmares more often than men do. Women report two to four nightmares for every one nightmare reported by men. It is unclear at this point whether men and women actually experience different rates of nightmares, or whether women are simply more likely to report them.
Nightmares are referred to by doctors as parasomnias — undesirable experiences that occur during sleep, usually during the stage of sleep known as rapid eye movement (REM).
You've had a nightmare if:
- Your dream wakes you.
- You feel scared, anxious, angry, sad or disgusted as a result of your dream.
- You can think clearly upon awakening, and can recall details of your dream.
- Your dream occurs near the end of your sleep time.
- Your dream keeps you from falling back to sleep easily.
Children's nightmare content varies with age, typically becoming more complex. While a young child might dream of monsters, an older child might have nightmares about school or difficulties at home.
Childhood nightmares are a normal maintenance function of the developing brain. They are a means of integrating recent and past learning and of establishing psychological equilibrium.
The following behaviors are usually present in a normal nightmare episode:
- Child awakens during the last third of her sleep period.
- Child is frightened and becomes fully alert.
- Child can describe the frightening dream in detail.
- Child seeks and responds to comfort and reassurance from a parent or caretaker.
- Child fears a recurrence of the frightful dream and may resist a return to bed.
When to see a doctor
Occasional nightmares aren't usually a cause for concern. If your child has nightmares, you can simply mention them at a routine well-child exam.
Talk to your doctor earlier if nightmares:
- Occur frequently and persist over time.
- Routinely disrupt sleep.
- Cause fear of going to sleep.
Nightmares can be associated with another sleep disorder. Many other factors can trigger nightmares, including:
- Stress. Sometimes the ordinary stresses of daily life, such as a problem at home or school, trigger nightmares. A major change, such as a move or the death of a loved one, can have the same effect.
- Trauma. Nightmares are common after an accident, injury or other traumatic event. Nightmares are prominent in post-traumatic stress disorder (PTSD).
- Scary books and movies. Reading scary books or watching scary movies, especially before bed, can cause nightmares.
- Bedtime snacks. For some, eating right before bed — and the resulting boost in metabolism and brain activity — leads to nightmares.
- Illness. Sometimes being sick triggers nightmares, especially if the illness is accompanied by a fever.
- Medications. Some drugs — including certain antidepressants, narcotics, barbiturates, beta blockers and drugs used to treat Parkinson's disease — can trigger nightmares.
- Substance abuse. Alcohol and illegal drugs can trigger nightmares.
Most nightmares occur during rapid eye movement (REM) sleep. You normally go through four to six sleep cycles a night, cycling through the sleep stages in about 90 minutes. Your REM stage lengthens with each cycle, from several seconds in the first cycle to up to an hour in the last. You're more likely to have a nightmare in the last third of your night.
The interpretation of and significance given to nightmares varies tremendously by culture. While some cultures view nightmares as indicators of mental health problems, others view them as related to supernatural or spiritual phenomena. Clinicians should keep this in mind during their assessments of the impact that nightmares have on clients.
How are nightmares related to PTSD?
Nightmares are 1 of 17 possible symptoms of PTSD. One does not have to experience nightmares in order to have PTSD. However, nightmares are one of the most common of the "re-experiencing" symptoms of PTSD, seen in approximately 60% of individuals with PTSD. A recent study of nightmares in female sexual assault survivors found that a higher frequency of nightmares was related to increased severity of PTSD symptoms. Little is known about the typical frequency or duration of nightmares in individuals with PTSD.
Are there any effective treatments for nightmares?
Yes. There are both psychological treatments (involving changing thoughts and behaviors) and psychopharmacological treatments (involving medicine) that have been found to be effective in reducing nightmares.
Psychological treatment for nightmares
In recent years, Barry Krakow and his colleagues at the University of New Mexico have conducted numerous studies regarding a promising psychological treatment for nightmares. This research group found positive results in applying this treatment to individuals suffering from nightmares in the context of PTSD.
Krakow and colleagues found that crime victims and sexual assault survivors with PTSD who received this treatment showed fewer nightmares and better sleep quality after three group-treatment sessions. Another group of researchers applied the treatment to Vietnam combat veterans and found similarly promising results in a small pilot study.
The treatment studied at the University of New Mexico is called "Imagery Rehearsal Therapy" and is classified as a cognitive-behavioral treatment. It does not involve the use of medications. In brief, the treatment involves helping the clients change the endings of their nightmares, while they are awake, so that the ending is no longer upsetting.
The client is then instructed to rehearse the new, nonthreatening images associated with the changed dream. Imagery Rehearsal Therapy also typically involves other components designed to help clients with problems associated with nightmares, such as insomnia. For example, clients are taught basic strategies that may help them to improve the quality of their sleep, such as refraining from caffeine during the afternoon, having a consistent evening wind-down ritual, or refraining from watching TV in bed.
Psychologists who use cognitive-behavioral techniques may be familiar with Imagery Rehearsal Therapy, or may have access to research literature describing it.