ABSTRACT
BACKGROUND: In laboratory studies, sleepiness has been found to increase dissociative symptoms. AIM: To explore the link between sleepiness and dissociation in a natural setting. METHOD: A longitudinal study was performed among volunteers at a pop festival. Information was collected via self-report scales at four successive test moments spread over a 12-hour period. RESULTS: Sleepiness was the only variable that could predict the increase in dissociative symptoms. This result was not mediated by a deteriorated mood. CONCLUSION: Our data suggest that sleepiness intensifies dissociative symptoms, even if it occurs outside a laboratory environment. Studies focusing on sleep normalisation may provide insights into new ways of treating dissociative symptoms.
