Journal of International Scholarship
January 1, 2026
William E. Kelly
Nightmares are distressing dreams that may stem from difficulties in regulating internal experiences rather than from specific psychiatric disorders. In 202 university students, impairments in self-functions (regulation and integration of internal experience) were strongly associated with nightmare proneness, which in turn was linked to greater nightmare frequency. The relationship between self-functions and nightmare frequency occurred primarily through nightmare proneness, with no significant direct association. These findings suggest that how people structure and regulate their internal experiences indirectly influences how often they have nightmares, via cognitive-affective processing patterns.
Individual Differences Research
December 1, 2023
Emily O. Cooper, William E. Kelly
A scale called the Nightmare Experience Scale (NExS) can accurately identify people who may have clinically salient nightmares, even in a nonclinical sample. In a study of 480 undergraduates, the NExS showed strong ability to distinguish those with possible clinically salient nightmares from controls, with an area under the curve of .941. A cut score of 9 or higher was found to be suitable for detecting potential cases. The findings suggest the NExS is a useful screening tool, but further research with clinical interviews is needed to confirm its value in clinical settings.
Individual Differences Research
December 1, 2020
William E. Kelly
Nightmares may reflect failures in emotional and self-regulation. Among 269 university students, weaker ego defensive functioning and low sensory thresholds predicted more nightmares, while higher drive regulation and cognitive control of autonomous functions also increased vulnerability. Ego functioning explained additional variance in nightmare frequency beyond gender and neuroticism. The findings suggest nightmares arise when the ego's balance between affective containment and expression is disrupted, reflecting both fragility and overcontrol.
Sleep Science
March 1, 2025
William E. Kelly, Richard C. Zamora, Soeun Park
Nightmare proneness—a disposition to have frequent nightmares—predicts how often people experience nightmares beyond what can be explained by neuroticism or general distress. In a cross-sectional study of 230 university students, nightmare proneness incrementally predicted nightmare frequency after accounting for neuroticism and distress. Additional analyses showed that neuroticism and distress indirectly predicted nightmare frequency through nightmare proneness, but nightmare proneness did not affect nightmares through those traits. The findings suggest nightmare proneness is a distinct psychological variable, not merely a reflection of neuroticism or distress.
Sleep science (Sao Paulo, Brazil)
March 1, 2023
William E. Kelly
Nightmare proneness—a stable tendency to have frequent nightmares—and general psychological distress are distinct but related constructs. In a cross-sectional study of 254 young adults, nightmare proneness remained linked to nightmares, nightmare distress, cardiac symptoms, sleep fragmentation, perceived physical health, perceived stress, and Type-D personality even after controlling for psychological distress. Conversely, distress remained connected only to perceived stress and Type-D personality after controlling for nightmare proneness. Nightmare distress, physical health, and nightmare proneness predicted cardiac symptoms, while posttraumatic nightmares, sleep fragmentation, distress, perceived stress, Type-D personality, and chest pain predicted nightmare proneness. These results support the idea that nightmare proneness involves hyperarousal, vulnerability to stressors, and concretization of vague internal states.