Examining the association among adolescents' emotional clarity, emotion differentiation, and the regulation of negative and positive affect using a daily diary approach.

Emotional clarity and emotion differentiation (ED) are two core aspects of the application of emotional knowledge. During adolescence, novel emotional experiences result in temporary decreases of differentiation and clarity. These temporary difficulties might profoundly impact choices of regulatory strategies. And indeed, prior research has shown that lower emotional clarity and emotion differentiation are each associated with higher use of putatively maladaptive emotion regulation strategies in youth. The two constructs, however, are rarely examined together, and it remains unclear how they are associated in daily life, particularly in children and adolescents. In addition, previous studies have focused on the regulation of negative but not positive affect. To address these gaps, the present study used an intensive longitudinal design in youth. Between June 2021 and March 2022, 172 children and adolescents ( = 12.99 years) completed a 28-day diary (> 3,500 entries in total) reporting daily affect, emotional clarity, and the use of five emotion regulation strategies in response to negative and positive affect (i.e., rumination, dampening, behavioral avoidance, negative and positive suppression). As predicted, on both between- and within-person levels, higher emotional clarity was associated with decreased use of all maladaptive emotion regulation strategies after adjusting for mean affect intensity. Results for emotion differentiation were mostly nonsignificant. Only higher daily positive emotion differentiation was associated with decreased rumination. In sum, this innovative study explores multiple aspects of emotional knowledge usage and regulation during a critical developmental stage and emphasizes the role of emotional clarity in the regulation of negative and positive affect. (PsycInfo Database Record (c) 2025 APA, all rights reserved).