What causes nightmares?

by Marc Wilson / 07 August, 2017
RelatedArticlesModule - Nightmares

Nightmares are a misfire in the process of consolidating the events of the day.

I’ve had my share of odd dreams. One of my earliest involved finding a Matchbox car, the coolest one I’d ever seen, beneath a tree in a garden. And I also remember the feeling of disappointment, upon waking, that the toy car hadn’t left my slumber with me.

Though many dreams include odd content, I don’t think of them as bad dreams or nightmares. When I do have the odd bad dream, I can usually pin it down to some kind of disturbance in my waking life.

I’m not alone. More than 80% of people will have had at least one nightmare in the past year that woke them. Bad dreams, on the other hand, involve negative occurrences and feelings but without jolting us from sleep. Both fall under a broader umbrella of “disturbed dreaming”.

Five to 10% of us experience weekly nightmares, however, and apart from not being fun, they can also be a problem. Idiopathic nightmares – ones that have no obvious cause and wake sufferers with feelings of intensified terror or dread – are a parasomnia listed in psychiatric and sleep disorder diagnostic manuals. They are the most common weird thing (excluding apnoea) that can happen during sleep.

Having “no obvious cause” is a little misleading, because we do know who is more likely to experience disturbed dreaming: females from age 14, people with a psychiatric diagnosis and those under extreme stress. The question is why do we have them?

According to New York sleep specialist Ross Levin, nightmares are a misfire in a normal everyday process – the consolidation of memories that occurs during sleep. When we nod off – and specifically during rapid eye movement, or REM, sleep – the brain is churning through the data that has come in during the day and smoothing it into the right shape.

Ross Levin.

Sometimes, what we’ve experienced is stressful, unpleasant or scary, and this is when we are more likely to have disturbed dreaming. The anxiety-provoking experiences are cut and pasted into a mash-up and re-experienced to rid them of their impact. Levin calls it “fear extinction”.

When the experience being processed is particularly frightening, and especially for people with high levels of baseline anxiety, the exercise can get a bit intense; that is, the mash-up sticks rather too closely to what we’ve actually been through.

Rather than processing these disjointed scenes out of the fraught context in which they happened, it’s more like being forced to watch a nasty psychological thriller from start to finish. We wake up and the memories don’t get sorted properly. Or, at least, that’s what I take from it.

Knowing where nightmares spring from is one thing. But doing something about them is a subject for another time.

Meanwhile, a reminder: parents are invited to participate in a confidential online survey about adolescent self-injury and youth well-being, for which you will receive a movie voucher. If that sounds like you, please visit tinyurl.com/PES17L or email youth-well-being@vuw.ac.nz. I will summarise the results of this research in a future column.

This article was first published in the July 15, 2017 issue of the New Zealand Listener.

Latest

Bill Ralston: Only fundamentalist Christians should be hurt by Israel Folau
104814 2019-04-20 00:00:00Z Social issues

Bill Ralston: Only fundamentalist Christians shoul…

by Bill Ralston

Israel Folau’s social-media post might condemn the Wallabies to Rugby World Cup hell, but the rest of us should ignore him.

Read more
What happens next with the Mueller report?
104863 2019-04-20 00:00:00Z World

What happens next with the Mueller report?

by Noted

Did Trump “corrupt” with intent?

Read more
The Heart Dances: Lifting the lid on the culture clash behind ‘The Piano’ ballet
104740 2019-04-20 00:00:00Z Movies

The Heart Dances: Lifting the lid on the culture c…

by Russell Baillie

Documentary offers an intriguing look at the clash of artistic sensibilities behind adapting The Piano into a ballet.

Read more
How this remarkable native insect is being saved
104836 2019-04-20 00:00:00Z Planet

How this remarkable native insect is being saved

by Jenny Nicholls

Principles of bird conservation are helping to save another remarkable native you’ve never heard of.

Read more
Environment Ministry 'unashamedly proud' of bleak report's honesty
104868 2019-04-20 00:00:00Z Planet

Environment Ministry 'unashamedly proud' of bleak…

by RNZ

The Secretary for the Environment Vicky Robertson said she was proud of the report's honesty and it was an important stocktake for the country.

Read more
The new What We Do in the Shadows is more dad joke than demonic
104712 2019-04-19 00:00:00Z Television

The new What We Do in the Shadows is more dad joke…

by Diana Wichtel

Diana Wichtel reviews a new American TV series based on the hit Kiwi comedy.

Read more
Louis & Louise is a satisfying exploration of gender and identity
104230 2019-04-19 00:00:00Z Books

Louis & Louise is a satisfying exploration of gend…

by Brigid Feehan

In her latest novel, Julie Cohen traces the parallel male and female lives of a single character.

Read more
Win a copy of Sir David Attenborough's Life on Earth: 40th Anniversary Edition
104844 2019-04-19 00:00:00Z Win

Win a copy of Sir David Attenborough's Life on Ear…

by The Listener

To celebrate Sir David Attenborough season on Sky, we are giving away copies of his book Life on Earth: 40th Anniversary Edition.

Read more