What causes nightmares and how to stop them

Chills run down your body. An electric charge snakes across your skin. Your pupils dilate. Your muscles tighten. You look into the darkness ahead and… the next morning you have absolutely no idea what happened. All you can remember is the sickening wash of fear as your mind was hijacked and held hostage by a nightmare.

It is not just children who encounter nightmares. Nearly 70 per cent of adults do as well, with 30 per cent of us reporting that these terrifying dreams jerk us out of sleep as often as once a month.

Nightmares can be triggered by medications, oddball genes, degenerative neurological diseases like Alzheimer’s, last night’s tamales, traumatic events in the present, never-healed wounds from the past that a recent event has unmasked, and gut-level threats to health, safety, and the very sense of who you are.

Those who suppress how they feel in response to stressful events during the day will likely be taken for a ride by those emotions in the form of nightmares at night.

Those who are particularly open and sensitive may have a thin boundary between what is real and what is a dream, which means that their waking life is more likely to stir up their night life and cause some pretty hairy dreams.

“A nightmare is a dysfunctional dream,” explains Rosalind Cartwright, PhD, director of the sleep disorder service at Rush Presbyterian–St. Luke’s Medical Center in Chicago.

Instead of integrating the day’s events and feelings with older, stored memories and defusing negative emotions—which is what some researchers feel a dream is supposed to do—the emotions your brain is processing overload your circuits, prevent their integration into older memories and jerk you from sleep.

If you are in a bad car accident, for example, you may not be able to process all the negative emotions the accident generates right away, says Dr Cartwright. The fear and your sense of vulnerability and mortality are overwhelming. So, you may have nightmares for a while as your mind keeps working away at integrating your feelings. Once it does, however, the nightmares disappear.

As Dr Cartwright eloquently writes in her book Crisis Dreaming, “Nightmares are a cry for resolution for finding a way to incorporate the terrible experience into our lives. Occasional nightmares are normal,” she adds. “But not nightly, and not over and over again.”

Some drugs—particularly antidepressants, barbiturates, sedatives, sleeping pills, beta-blockers, catacholaminergic agents, and amphetamines—can trigger nightmares. Surprisingly, so can the common antibiotic erythromycin and the over-the-counter anti-inflammatory naproxen. Other culprits include:

“Major depression usually wipes out dreaming altogether,” says Dr Cartwright. “Depressed people usually have no recall of dreaming, no dream content, no story. If they do, it is very short, very bland, with no feeling at all.

“As they recover from depression, however, their ability to dream comes back, and their dreams get more elaborate and full of emotion.” Unfortunately, those recovering from depression can sometimes overshoot and be flooded with negative emotions.

“That is when suicides can occur,” cautions Dr Cartwright. So, it is crucial that anyone who is depressed report nightmares to their doctor immediately.

Nightmares are a sign of overload. Check with a doctor, psychiatrist, or therapist if you are depressed, if the nightmares recur, or if you discover that your dreams are caused by distressing feelings from the past that have been triggered by current events. Otherwise, here’s how Dr Cartwright suggests you keep them at bay:

Recognise that the dream is bad while you have it. This may sound impossible, but it is not. Simply resolve that you are going to do this before you fall asleep. It may take a few tries, but you will eventually get the hang of it.

Identify what in the dream makes you feel bad. What are the feelings or events involved?

Stop any bad dream. Believe it or not, you can do it—often simply by recognising that it is bad.

Change the ending. Turn what is negative into something positive. You may have to wake up to do it, but eventually, you will be able to tell yourself to write a better ending as you sleep.

Keep a dream diary. Write down your dreams every morning. All your dreams, not just the nightmares. Then periodically review the ones that trouble you. Try to figure out why they are upsetting.

Banner credit: Grandfailure

Read more: The science of dreaming

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