New research by Dr. Liam Kelly sheds light on the causes of nightmares and the distress they cause.

“There has been a long debate about what causes a nightmare as opposed to a regular dream,” Kelly explains, “but most of the research has occurred just in the last 50 years.” The focus of these studies has been not just on the frequency of nightmares but also on the distress they cause.

Kelly’s findings indicate that long-standing personality traits may be as influential in nightmare frequency and distress as temporary emotional states.

In the history of this “states vs. traits" argument, the influence of emotional states has been considered the primary cause. The connection seems logical. It is easy to imagine that external factors which produce amplified emotions may cause nightmares.

Kelly and co-author John Mathe, however, added to the mix several personality traits that had not been measured previously.

Nightmare frequency, they found, is connected to people who have “thin boundaries” (easily mixing various experiences) and who are disposed to concretize vague, negative feelings into experiences like headaches, stomach aches, and images.

Predictors of nightmare distress were emotional dysregulation (an inability to keep calm) and low ego strength (the ability to regulate feelings about yourself and adapt), suggesting that individuals with weaker capacities to manage stress and regulate emotions experience more distress from their nightmares.

“I’ve always been fascinated by dreams,” says Kelly. “I’ve never had many nightmares myself, but those that I’ve had have been memorable. Maybe that’s why they have been my primary area of research since 2015. They’re a mystery and have profound implications for some people.”

Nightmares have been linked to heightened emotional distress, symptoms of post-traumatic stress, paranoia, and even an increased risk of suicide.

His research was published in the journal Dreaming.

The Louisiana native has been at Neumann for two years. He teaches in the clinical mental health counseling master’s degree program and occasionally in the undergraduate psychology program. He also maintains a small, private counseling practice.