Comparison of Dream Themes, Emotions and Sleep Parameters between Nightmares and Bad Dreams in Nightmare Sufferers

Objectives: The current study aimed to explore the difference of dream themes, emotional intensity, and sleep parameters between nightmares and bad dreams in nightmare sufferers.Methods: Twenty-four nightmare sufferers who endorsed clinical levels of nightmares (Disturbing Dream and Nightmare Severity Index Scores ≥10) recorded daily information about their dream themes using a modified version of the Typical Dreams Questionnaire, emotional intensity about their nightmares and bad dreams, and sleep for two weeks on a mobile device.Results: Evil presence (35%) was reported with higher frequency in nightmares, whereas interpersonal conflicts (31%) were predominantly reported in bad dreams.Nightmares were rated substantially more emotionally intense than bad dreams.Especially, fear (Z=-2.118,p=0.034) was rated as being significantly higher in nightmares than bad dreams.There were differences on time in bed, wake after sleep onset, sleep efficiency on the days with nightmares or bad dreams compared to other days; however, there were no differences in sleep parameters between nightmares and bad dreams.Conclusions: The results suggest that nightmares may be qualitatively and quantitatively different from bad dreams in nightmare sufferers. J Sleep Med 2016;13(2):53-59