Bidirectional Dynamics of Dual Systems and Problematic Internet Use in Children and Adolescents: A Person-Centered...

Problematic Internet Use (PIU) is a critical public health issue, especially among children and adolescents. The Dual Systems Model posits that imbalances between reward processing and self-control systems increase PIU vulnerability, with potential reciprocal effects of PIU on these systems. However, previous studies have primarily employed variable-centered approaches, neglecting within-system heterogeneity, and longitudinal studies on bidirectional relationships have mostly focused on single system, with limited evidence in children.

The present study fills these research gaps by utilizing person-centered approaches to explore bidirectional relationships in 1341 children (9-11 years) and adolescents (13-16 years). A 1-year longitudinal survey measuring reward sensitivity, self-control, and PIU was conducted, combined with latent profile transition analysis and supervised machine learning.

The results showed developmental similarities and differences. First, dual systems patterns predicted PIU in both age groups, but the underlying mechanisms were different. Low reward sensitivity and low self-control in children and adolescents increased PIU risk, while adolescents also uniquely affected by high reward sensitivity and low self-control. Second, PIU only reduced reward sensitivity and self-control over time in children.

The present study enriches the Dual Systems Model by demonstrating bidirectional relationships from a person-centered perspective and informs tailored PIU interventions based on developmental stage and dual-system profiles.