Ping Ren

Gaining and maintaining popularity is a central concern during early adolescence, and adolescents experiencing social status insecurity may turn to bullying in attempts to improve their standing. However, it remains unclear whether bullying truly yields its intended social rewards and whether these associations differ across classroom popularity norms. This study investigated bullying as a potential mediator linking social status insecurity to popularity over time and examined classroom popularity norms as a contextual moderator. A total of 2,310 adolescents (51.6% boys at T1; M_age = 12.36, SD = 0.69) from 49 classes were assessed across five waves over two years. Random-intercept cross-lagged panel models showed that bullying did not mediate the association between social status insecurity and popularity, regardless of peer-nominated or self-reported measures. Multi-group analyses further indicated that popularity norms moderated within-person associations differently: in low-norm classrooms, associations were generally non-significant, whereas in high-norm classrooms, social status insecurity and bullying were positively associated, yet bullying did not increase subsequent peer-nominated popularity and even negatively predicted self-reported popularity. These findings highlight that bullying rarely produces the expected social benefits, providing insights for more targeted and effective interventions to reduce bullying.

Loneliness and non-suicidal self-injury are significant mental health concerns during adolescence, yet less is known about how they develop together across middle school and whether changes in one are followed by changes in the other. The present study addressed this issue using six waves of longitudinal data collected over three years from 3,800 Chinese middle school students (Mage = 12.38, SD = 0.51; 49.4% female). Across middle school, loneliness tended to increase, whereas non-suicidal self-injury tended to decline. These developmental trends were also linked: higher initial loneliness was associated with a slower decline in non-suicidal self-injury, whereas higher initial non-suicidal self-injury was associated with steeper increases in loneliness. At the within-person level, elevated loneliness predicted subsequent increases in non-suicidal self-injury, whereas fluctuations in non-suicidal self-injury did not predict subsequent increases in loneliness. Sensitivity analyses further suggested that this within-person association was more consistent with a direction from loneliness to non-suicidal self-injury, although the data could not clearly determine whether the association was primarily lagged or contemporaneous. Together, these findings suggest that loneliness and non-suicidal self-injury are linked across both long-term developmental trajectories and short-term within-person fluctuations, while also highlighting the more prominent role of loneliness in their relationship during middle school.

Affect reactivity to negative events is considered a vulnerability factor for mental health problems; however, its role in internet addiction has been less explored. Based on the Interaction of Person‐Affect‐Cognition‐Execution model, this study investigated whether affect reactivity to negative events in two key interpersonal domains—parents and peers—contributes to the development of internet addiction during the transition from Grade 8 to Grade 9 among Chinese adolescents. A 12‐day daily diary combined with a 6‐month longitudinal design was used to collect data from 244 Chinese adolescents ( M _age = 13.87, SD _age = 0.51, 42.6% girls). Results revealed that internet addiction remained relatively stable but demonstrated significant individual differences over the 6‐month transition from Grade 8 to Grade 9. At the within‐person level, daily negative parent and peer events were associated with higher levels of negative affect. Moreover, daily affect reactivity to negative peer events, but not negative parent events, predicted a faster increase in internet addiction over 6 months. The findings highlight the critical role of affect reactivity to negative peer events in the development of internet addiction and offer insights for targeted prevention strategies.

Parents and friends are critical social influences on adolescents’ academic achievement, yet how they function together within dynamic friendship networks remains insufficiently understood. This study examined how parental influences (autonomy support, behavioral control, psychological control, and educational expectations) interact with friendship selection and influence processes to shape academic achievement of Chinese adolescents. A total of 1,419 Chinese adolescents ( M _age = 12.35, SD = 3.04; 46.4% girls) participated in four-wave surveys across two years. Longitudinal social network analyses revealed a clear friendship influence process, with adolescents’ achievement becoming increasingly similar to that of their friends over time. Parental influences operated through distinct pathways: perceptions of high parental expectations directly increased achievement, whereas autonomy support and psychological and behavioral control had no direct effect. Adolescents perceiving high parental autonomy support were more likely to select high-achieving friends; other parental influences did not affect friendship selection. No parental influences moderated the effect of friends influence on achievement. Overall, these findings suggest that parents shape adolescents’ achievement by setting expectations and providing support, either directly or via friendship selection, while friends exert an independent influence on achievement. Taken together, the results highlight how both parents and friends contribute adolescents’ academic development in the Chinese context.

Defenders are critical in preventing school bullying, yet the association of their heterogeneity with social-ecological factors remains underexplored, especially over long-term development. Using a multilevel framework, this longitudinal study examined subgroups of defenders among Chinese adolescents, their distribution patterns at the classroom level, and how social-ecological factors influence these subgroups. Data were collected from 3569 junior high school students (initial M_age = 12.69 ± 0.49, 47.5% girls) across 76 classrooms in three waves at half-year intervals. Multilevel latent profile analysis identified six defender subgroups (frequent aggressive, frequent nonaggressive, moderate aggressive, moderate nonaggressive, infrequent, and nondefenders) and two classroom patterns (high- and low-defending). From the first to the second semester of eighth grade, nonaggressive defenders generally decreased, while aggressive, infrequent, and nondefenders increased at both the student and classroom levels. Furthermore, social status, classroom status hierarchy, and classroom bullying norms predicted defender subgroups, with effects that varied over time. These findings emphasize the necessity of considering defender heterogeneity from a social-ecological perspective and offer insights for classroom-level interventions.