Characterizing emotional dynamic trajectories in adolescents: A two‐year longitudinal study with an ecological momentary assessment design

Most research on emotional functioning focuses on the intensity of emotions. Little is known about how current emotion predicts future emotion, or how emotions fluctuate. Understanding how day-to-day emotional dynamic indices change over time, especially during adolescence, is important, as this developmental stage represents a critical period for emotional development. This study investigates the developmental trajectories of emotional dynamics in adolescents. One hundred seventy nine adolescents (44.1% males, M_age = 12.80 ± 0.41) at baseline participated in the current study as part of a larger longitudinal study (the Circadian Light in Adolescence, Sleep and School [CLASS] Study). Positive and negative affect were assessed daily via ecological momentary assessment (EMA) for 2 weeks every 6 months over 2 years. Bayesian multilevel location scale models were used to characterize emotional dynamic trajectories. Positive affect inertia (p = .005) and variability (p < .001) decreased, and negative affect intensity (p = .015) increased significantly over time. Higher positive affect intensity was associated with lower positive affect variability, with a coefficient of -.25. All negative affect dynamic indices were significantly correlated with each other (r = .26 to .75). Adolescent's negative affect intensity increased with age, while positive affect inertia and variability decreased. The increase in negative affect intensity, combined with its positive relationship to emotional problems, may heighten vulnerability to negative emotional states. The reduction in positive affect inertia and variability suggests improved flexibility in regulating positive affect, potentially offering a stabilizing effect. Research should explore their link to clinical mood disturbances and their potential as early warning signs.