Bad dreams can be distressing — and the severity of this distress partly depends on the way you appraise them, according to recent findings published in the Journal of Sleep Research. The study found that the emotional appraisal of a dream had a greater influence on nightmare distress than violent content.
Nightmares are built around frightening themes and can contain vivid, violent content. But a 2020 study by Jonas Mathes and colleagues suggested that a nightmare is not just a dream with frightening content. For a dream to be considered a nightmare, it also needs to be negatively appraised by the dreamer.
In a new study, Mathes and associates tested whether a dreamer’s emotional appraisal of a dream would impact their nightmare distress. Would dreams that arouse more negative emotions cause more distress, irrespective of their content?
“I was interested in this topic because my previous research shows that dream emotions are not necessarily identical with dream contents,” Mathes told PsyPost. “A good example are the so-called offender-nightmares (nightmares, where the dream-self acts as the aggressor instead of the victim). They illustrate that dreams can be perceived as a nightmare, even if the dream-self is not a victim in his or her dreams.”
“Both dream contents and emotional appraisal are important factors in nightmare development. I wanted to differentiate the impact factors from waking-life for nightmares more precisely.”
The researchers recruited a sample of 103 subjects to participate in an online study. Of these participants, 59 had more than one nightmare per month (the nightmare group) and 44 did not have more than one nightmare per month (the non-nightmare group).
The participants completed online questionnaires which included measures of dream recall frequency, childhood trauma, critical life events, and nightmare distress. They then filled out an online dream diary where they recorded their dreams every morning for 28 days. Participants wrote narratives of their dreams, rated the emotional intensity of each dream, and indicated whether they perceived each dream as a nightmare.
Across the whole sample, participants who reported a greater number of critical life events and more violent dream content reported higher nightmare distress. When comparing the nightmare group to the non-nightmare group, participants in the nightmare group reported a greater number of critical life events, more frequent nightmares, more violent dream content, and higher scores for traumatic childhood experiences. The nightmare group also reported more negative dream emotions while the non-nightmare group reported more positive dream emotions.
Mathes and associates next tested for predictors of nightmare distress. As expected, violent dream content was a significant predictor of nightmare distress. But in a model that included additional predictors — nightmare frequency, dream contents, critical life events, emotional abuse, and negative dream emotions — the impact of violent dream content decreased. And in this model, critical life events, emotional abuse, and the intensity of negative dream emotions were significant predictors of nightmare distress.
According to the study authors, these findings suggest that childhood trauma, critical life events, and the emotional appraisal of a nightmare are all important factors that contribute to nightmare distress. In fact, these factors were more influential than violent dream content. Seemingly, a dream can be interpreted with negative emotions and cause distress even if it contains little aversive content.
“Waking-life distress has an important impact on bad dream emotions, which shows us that nightmares can also be treated effectively,” Mathes explained. “For example, the imagery rehearsal therapy, where typical dream contents are rehearsed to re-appraise from waking-life.”
The findings are also in line with the stress acceleration hypothesis, which suggests that nightmares in adulthood can be the product of early traumatic experiences that the adult no longer recalls. Supposedly, these early negative experiences can activate neural fear pathways and cause recurrent nightmares even if the experience is no longer remembered.
A limitation of the study is that childhood trauma was assessed through retrospective reports and may have been impacted by participants’ memory biases. Nonetheless, the findings suggest that the emotional appraisal of a dream has an impact on nightmares and that, “dreamers can influence their dream experiences due to their reappraisal during the dream or probably also in waking-life.”
The study, “Nightmare distress is related to traumatic childhood experiences, critical life events and emotional appraisal of a dream rather than to its content”, was authored by Jonas Mathes, Jennifer Schuffelen, Annika Gieselmann, and Reinhard Pietrowsky.