Abstract
Adolescence is a crucial time of identity formation, scholastic and social demands, future concerns, and relationship changes. Adolescents are especially susceptible to psychological issues like pessimism, which can hinder their progress and well‐being. Cognitive flexibility may help adolescents adjust to these challenges and improve subjective well‐being. Pessimism, cognitive flexibility, and subjective well‐being have been investigated cross‐sectionally, but their longitudinal association has not. This study examines cognitive flexibility's mediation function in the longitudinal association between pessimism and subjective well‐being in teenagers, taking into account their well‐being development and inadequacies. This study looked at how cognitive flexibility affects the link between pessimism and subjective well‐being. To address the limitations of cross‐sectional mediation analysis, the current study employed an autoregressive cross‐lagged panel model within a half‐longitudinal framework, which allows for a more accurate estimation of directional and temporal relationships among the variables. This model used two 3‐month‐apart data sets. Cognitive flexibility was found to mediate the relationship between pessimism and subjective well‐being (χ2 (3, N = 232) = 11.68, p < 0.001). These findings indicate that cognitive flexibility plays a significant mediating role in weakening the negative impact of pessimism on adolescents’ subjective well‐being, highlighting its importance as a protective cognitive factor during this critical developmental period.