Nightmare proneness

Background: Nightmare proneness has been associated with insomnia beyond nightmare frequency and neuroticism. The present study examined physiological hyperarousal as a potential process contributing to this relationship. Methods: Participants were 209 adults recruited from a university participant pool and an online community sample. Participants completed self-report measures of nightmare proneness, insomnia, physiological hyperarousal, nightmare frequency, neuroticism, and trauma symptoms. Hierarchical regression and indirect-effect analyses were conducted. Results: After controlling for recruitment source, gender, nightmare frequency, neuroticism, and trauma symptoms, nightmare proneness explained an additional 6.5% of the variance in insomnia. Physiological hyperarousal accounted for an additional significant 2.2% of variance beyond nightmare proneness. Nightmare proneness showed a significant indirect association with insomnia through physiological hyperarousal. However, nightmare proneness maintained an direct association with insomnia outside physiological hyperarousal. Conclusion: Physiological hyperarousal may represent one process contributing to the relationship between nightmare proneness and insomnia but does not fully account for this association. The findings support conceptualizing nightmare proneness and physiological hyperarousal as related but non-redundant factors associated with insomnia.