Adapting after adversity: Psychological inflexibility mediates the influence of adverse childhood experiences on changes in undergraduates' insomnia symptoms.

Objectives: This study sought to model the indirect effect of adverse childhood events on relative changes in college students' symptoms of insomnia through their capacities to be both psychologically flexible and inflexible. Participants: A total of 359 undergraduates (86.6% female; M_age = 21.2; SD = 2.4) from four universities were surveyed during the Spring 2023 semester. Methods: Subjects completed measures of adverse childhood events (baseline), psychological flexibility/inflexibility (baseline), and insomnia symptoms (at baseline and 2-month follow-up), in addition to key covariates (e.g., sleep hygiene and melatonin use). Results: Results, based on a mediation model, suggested that more adverse childhood experiences were associated with higher levels of psychological inflexibility, which, in turn, were associated with residual increases in students' symptoms of insomnia across the two months of the study. Conclusions: The current results highlight the significant role that psychological inflexibility plays in undergraduates' sleep problems and potentially expand avenues for addressing this population's sleep needs.