A nightmare is a dream occurring during rapid eye movement (REM) sleep that results in feelings of inescapable terror, fear or extreme anxiety. This phenomenon tends to occur in the latter part of the night and oftentimes awakens the sleeper, who is likely to recall the content of the dream. Most nightmares may be a normal reaction to stress, and some clinicians believe they aid people in working through traumatic events.
Frequent occurrence of nightmares becomes a disorder when it impairs social, occupational and other important areas of functioning. At this point, it may be referred to as Nightmare Disorder (formerly Dream Anxiety Disorder) or "repeated nightmares." "Repeated nightmares" is defined more specifically as a series of nightmares with a recurring theme. Nightmares usually begin in childhood before age 10 and are considered normal unless they significantly interfere with sleep, development or psychosocial development. They tend to be more common in girls than boys, and they may continue into adulthood. Adult nightmares are often associated with outside stressors or exist alongside another mental disorder. Nightmares might be associated with anxiety and trauma.
A closer look at dreaming might help in understanding nightmares.
Dreaming and REM Sleep
We typically spend more than two hours each night dreaming. Scientists do not know much about how or why we dream. Sigmund Freud, a major influence in psychology, believed dreaming was a "safety valve" for unconscious desires. Only after 1953, when researchers first described REM in sleeping infants, did scientists begin studying sleeping and dreaming carefully. They soon discovered that the strange, illogical experiences we call dreams almost always occur during the REM part of sleep. While most mammals and birds show signs of REM sleep, reptiles and other cold-blooded animals do not.
REM sleep begins with signals from the pons, an area at the base of the brain. These signals travel to a region called the thalamus, which relays them to the cerebral cortex—the outer layer of the brain responsible for learning, thinking and organizing information. The pons sends signals that shut off neurons in the spinal cord, causing temporary paralysis of limb muscles. If something interferes with this paralysis, people will begin to physically act out their dreams—a rare, dangerous problem called REM sleep behavior disorder. For example, a person dreaming about a baseball game may run into furniture or inadvertently strike a person sleeping nearby while trying to catch a ball in the dream.
REM sleep stimulates the brain regions used in learning, which may be important for normal brain development during infancy. This would explain why infants spend much more time in REM sleep than adults. Like deep sleep, REM sleep is associated with increased production of proteins. One study determined that REM sleep affects learning certain mental skills. People taught a skill and then deprived of non-REM sleep were able to recall what they had learned after sleeping, while people deprived of REM sleep were not.
Some scientists believe dreams are the cortex's attempt to find meaning in the random signals received during REM sleep. The cortex is the part of the brain that interprets and organizes information from the environment during consciousness. One theory suggests that, given random signals from the pons during REM sleep, the cortex, attempting to interpret these signals, creates a "story" out of fragmented brain activity.top of page Symptoms
Criteria for Nightmare Disorder
Nightmares tend to be more common among children and become less frequent toward adulthood. Nevertheless, about 50 percent of adults experience occasional nightmares, women more often than men, and do not require any treatment. Eating just prior to going to bed, which raises the body's metabolism and brain activity, may cause an increase in nightmares. Approximately 1 percent of adults will experience repeated nightmares and should seek help.top of page Causes
If you are experiencing severe stress, you should seek out the support of friends and relatives. Talking about what is on your mind can go a long way. It is also recommended that you follow a regular fitness routine, including aerobic exercise if possible. You will find yourself able to fall asleep faster, having a deeper sleep and waking up feeling more refreshed. Learn techniques to reduce muscle tension (relaxation therapy), which will also help lessen anxiety.
Avoid long-term use of tranquilizers, and avoid caffeine and other stimulants.
If your nightmares started shortly after beginning a new medication, contact your health-care provider. He or she will advise you on discontinuing that medication if necessary and recommend an alternative.
For nightmares resulting from the effects of "street drugs" or persistent alcohol use, seek counsel on discontinuing usage. Alcoholics Anonymous, for example, might suggest a safe way for you to stop drinking. You can also attend their regularly scheduled meetings. In addition, look at your lifestyle—friends, work and family—to rid yourself of factors that encourage substance abuse.
Call your health-care provider if nightmares occur more often than weekly, or if they prevent you from getting a good night's rest and persist for a prolonged period. Your medical history will be obtained and a physical examination performed.
Medical history questions documenting nightmares in detail may include:
Physical examination may include physical, neurological and psychological assessments.
If treatment options addressing stress and anxiety, side effects of medication and substance use, do not resolve the problem, your health-care provider may send you to a sleep specialist who will perform a sleep study (polysomnography). In extremely rare cases, a patient will need to take special medications that suppress or reduce REM sleep, thus preventing nightmares.
After an examination by your health-care provider, you may want to add a diagnosis related to recurrent nightmares to your personal medical record.
Tips for a Good Night's Sleep From the National Sleep Foundation
Set a schedule
Go to bed at a set time each night and get up at the same time each morning. Disrupting this schedule may lead to insomnia. Sleeping in on weekends makes it harder to wake up early on Monday morning as it resets your sleep cycles for a later awakening.
Aim to exercise 20 to 30 minutes a day. Daily exercise often helps people sleep, although a workout before bedtime may have an adverse effect. For maximum benefit, work out about 5 to 6 hours before going to bed.
Avoid caffeine, nicotine and alcohol
Avoid drinks that contain caffeine, a stimulant. Sources of caffeine include coffee, chocolate, diet drugs, soft drinks, non-herbal teas and some pain relievers. Smokers tend to sleep very lightly and often wake up in the early morning due to nicotine withdrawal. Alcohol robs people of deep sleep and REM sleep, keeping them in the lighter stages.
Relax before bed
A warm bath, reading or another soothing routine can make it easier to fall sleep. You can train yourself to associate certain restful activities with sleep and make them part of your bedtime ritual.
Sleep until sunlight
If possible, wake up with the sun, or use very bright lights in the morning. Sunlight helps the body's internal clock reset itself daily. Sleep experts recommend exposure to an hour of morning sunlight for people having sleep issues.
Don't lie in bed awake
If you can't fall asleep, don't just lie in bed. Do something else, like read, watch TV or enjoy music, until you feel tired. The anxiety of being unable to fall asleep can actually contribute to insomnia.
Control room temperature
Maintain a comfortable temperature in the bedroom. Extreme heat or cold may disrupt sleep or prevent you from falling asleep.
See a doctor if your sleeping problem continues
If you have trouble falling asleep every night, or if you always feel tired the next day, then you may have a sleep disorder and should see a physician. Your primary care physician may be able to help you; also, you can probably find a sleep specialist at a major hospital near you. Most sleep disorders can be treated effectively.
Researchers now know that sleep is an active and dynamic state that strongly influences our waking hours. Innovative techniques, such as brain imaging, help researchers understand how different brain regions function during sleep and how activities and disorders affect sleep.
In fact, scientists have had success in controlling dreams. In one experiment, subjects were trained to play the computer game, Tetris, involving the manipulation of pieces of a falling wall. The scientists monitored the subjects' dreams over the first two nights, and more than half of the subjects reported dreaming of falling Tetris pieces. This type of research will most likely contribute to developing treatments for nightmares.
Last Reviewed By: Laura Stephens