Relationships Between Cognitive Disengagement Syndrome, Impulsivity, and Emotion Regulation Among Adolescents

Objective: Cognitive disengagement syndrome (CDS) is associated with internalizing symptoms, emotion regulation (ER) difficulties, daytime sleepiness, and impulsivity; however, their interrelations in adolescents with subthreshold attention-deficit/hyperactivity disorder (ADHD) remain underexamined. This study aimed to evaluate the relationships between CDS, ADHD symptoms, ER problems, daytime sleepiness, trait impulsivity, and internalizing symptoms and to determine the mediating roles of ER problems and daytime sleepiness. Methods: This cross-sectional, clinic-based study included 144 treatment-naïve adolescents (12–18 years) referred for inattention and/or hyperactivity/impulsivity complaints. Parent-reported measures ( Conners Parent Rating Scale-Revised-Short Form (CPRS-R-SF) ; Child and Adolescent Behavior Inventory-Sluggish Cognitive Tempo Scale (CABI-SCT ) and adolescent self-reports ( Pediatric Daytime Sleepiness Scale PDSS , Revised Child Anxiety and Depression Scale-Child Version RCADS-CV , Difficulties in Emotion Regulation Scale-Short Form DERS-16 , Barratt Impulsiveness Scale-Brief ) were administered. Pearson correlations with Bonferroni–Holm correction and structural equation modeling were performed. The CPRS ADHD index and CABI-SCT served as predictors, DERS-16 and PDSS as mediators, RCADS-CV-Total as the outcome, and trait impulsivity, sex, and socioeconomic status were included as confounders. Results: CDS showed moderate-to-high correlations with ADHD indices and significant associations with all internalizing domains except separation anxiety. CDS and daytime sleepiness were moderately correlated, and both were significantly associated with ER difficulties. Trait impulsivity correlated with CDS, ER problems, and internalizing symptoms. CDS was associated with internalizing symptoms through an indirect pathway involving ER difficulties, whereas daytime sleepiness did not a significant mediating effect. Trait impulsivity significantly predicted CDS, ADHD symptoms, ER difficulties, and daytime sleepiness, supporting its role as a shared vulnerability factor. Conclusion: CDS symptoms appear more closely related to ER difficulties and internalizing symptoms than subthreshold ADHD symptoms in clinically referred adolescents. ER problems may represent a key mechanism linking CDS to internalizing psychopathology. Routine assessment of CDS symptoms, ER skills, and sleep-related problems may facilitate early identification of at-risk youth. Interventions targeting ER skills and sleep-related processes may represent potential targets for future interventional research, and that longitudinal studies using multimethod assessments are needed to clarify causal pathways.