Exploring within and between associations of momentary mindfulness and emotion regulation and the moderating effects of mental health among adolescents.

Greater mindfulness is thought to give rise to more positive psychological health through more adaptive emotion regulation. While there is extensive evidence linking higher average mindfulness to lower average emotion regulation difficulties, less is known about the momentary-level patterns that occur within individuals. Additionally, it is unclear if the relationship between mindfulness and emotion regulation changes as a function of adolescents' mental health status. This study sought to fill these gaps by investigating the between- and within-person concurrent (same moment) and prospective (next moment) effects of mindfulness on emotion regulation among adolescents exposed to chronic stressors. This study also explored the moderating effects of mental health symptoms. Seventy-nine participants who were 10-18 years old (M = 13.81; SD = 2.16; 56% male; 62% non-Hispanic White) completed ecological momentary assessments (EMA) three times a day for 7 days. Dynamic structural equation modeling revealed that between- and within-person mindfulness was inversely associated with concurrent, but not prospective, emotion regulation difficulties. Post-traumatic stress disorder (PTSD) and internalizing symptoms also moderated concurrent and prospective within-person associations. Individuals with higher PTSD and internalizing symptoms experienced lower emotion regulation difficulties during moments of greater-than-average mindfulness. Adolescents with higher PTSD symptoms also experienced fewer difficulties regulating their emotions in moments that followed greater mindful nonjudgment. These results highlight that greater momentary mindfulness may be beneficial for emotion regulation within the same moment and across the day for adolescents with mental health difficulties which has meaningful implications for just-in-time interventions. Future research may benefit from incorporating additional EMA measurements to explore the finer grained, short-term dynamics between mindfulness and emotion regulation.