SLEEP AND BIOLOGICAL RHYTHMS, vol.10, no.1, pp.14-22, 2012 (SCI-Expanded)
Morning and evening-type individuals differ on a number of psychological and biological variables. In this study, we aimed to investigate the relationship between sleep quality, dream anxiety, and chronotypes. A sample of 264 university students, aged between 17 and 26 years, completed the MorningnessEveningness Questionnaire, the Pittsburgh Sleep Quality Index, and the Van Dream Anxiety Scale for assessing nightmare frequency and the dream anxiety caused by frightening dreams. Main findings indicated that evening-type individuals were significantly more likely to suffer from poor sleep quality, daytime dysfunction, nightmares, and nightmare-related disturbances as compared to either intermediate- or morning-type individuals. Previous studies have pointed out the possible connections of irregular sleepwake habits and circadian dysregulation with a tendency to reveal eveningness chronotypical characteristics. Current findings suggest that evening-type individuals are more prone to experience psychologically deteriorating nightmares and sleep-related anxiety. Poor sleep quality is also a significant antecedent of dream anxiety after controlling for age and gender.