Purpose: To explore the relationship between adolescents’ emotion regulation ability and non-suicidal self-injury (NSSI) behavior and the role of sleep, exercise, and social support in this relationship. Methods: A total of 2573 adolescents were investigated with the Cognitive Emotion Regulation Scale, the Social Support Scale for Children and Adolescents, the Ottawa Self-Injury Questionnaire, and the Self-Made Living Condition Questionnaire, and path analysis was conducted based on the structural equation model (SEM). Results: 1) There was a significant correlation between emotion regulation ability and NSSI behavior; 2) sleep and social support played a mediating role between emotion regulation ability and NSSI behavior; and 3) sleep modulated the direct effect of negative emotion regulation ability on NSSI, while exercise modulated the direct effect of positive emotion regulation ability on NSSI, which indicated that sleep and exercise could effectively alleviate NSSI behavior caused by the lack of emotion regulation in adolescents.

Purpose: To explore the impact of the match between academic pressure and peer support on adolescents’ sense of loneliness and examine whether social connectedness played a mediating role, using a polynomial regression and response surface analysis. Methods: A questionnaire survey was conducted with 1277 adolescents from two cities in Sichuan Province, China, to investigate their academic pressure, peer support, social connectedness, and sense of loneliness. Results: (1) Adolescents’ sense of loneliness positively correlated with their level of academic pressure and negatively correlated with their degree of peer support. (2) Social connectedness played a mediating role in the relationship between academic pressure, peer support, and sense of loneliness. (3) Adolescents with high academic pressure and low peer support had weaker social connectedness than those with low academic pressure and high peer support. (4) Adolescents with high academic pressure and high peer support had stronger social connectedness than those with low academic pressure and low peer support. Discussion: The study revealed the mechanism through which a match (or mismatch) between academic pressure and peer support influenced adolescents’ sense of loneliness and validated the mediating role of social connectedness. The study enriches the developmental theory of adolescent loneliness and provides research experience for future interventions targeting adolescent loneliness.

Purpose: This study explore the interaction between loneliness and non-suicidal self-injury behaviors (hereinafter “NSSI”), and to further examine the mediating role of self-control and the moderating role of social connection. Methods: A total of 414 junior high school students (age 14.05± 0.84) in Sichuan province in China were investigated on their loneliness, self-control, social connection and NSSI by questionnaire. Results: (1) there was a significant positive correlation between loneliness and NSSI; (2) self-control played a mediating role in the relationship between loneliness and NSSI; and (3) after controlling for gender, family structure, and family economic level, the social connectedness played a moderating role in the relationship between loneliness and NSSI, as well as between self-control and NSSI. Conclusion: The results verify the relationship between loneliness and NSSI, expands and deepens the internal logical relationship between them, and provides a reference that can be used in the future for the prevention and intervention of NSSI in adolescents.

Short videos, with their brevity and high entertainment value, attract many adolescent users. However, prolonged viewing may negatively impact adolescents’ cognitive development, especially self-control and academic performance. This study explores the impact of the family environment on adolescents’ addiction to short videos and reveals the intrinsic role of psychological capital and self-control in the relationship between the family environment and adolescents’ short video addiction. Based on ecosystem theory, a hypothetical model was constructed in which psychological capital and self-control serve as chained mediators in the influence of the family environment on short video addiction. Revised scales for family environment, psychological capital, self-control, and short video addiction were used to conduct a survey among 1,735 middle school students from five provinces in China (51.7% male; M age = 15.2, SD = 1.8). This study found that: (1) A positive family environment, psychological capital, and self-control are significantly negatively correlated with adolescents’ short video addiction; (2) The mediating effect of psychological capital between the family environment and short video addiction is not significant; (3) Self-control has a significant mediating effect between the family environment and short video addiction (6.8%); (4) Psychological capital and self-control have a significant chained mediating effect between the family environment and short video addiction (12.8%). The family environment has a significant impact on adolescents’ short video addiction. Close family relationships and rich family recreational activities help reduce the risk of addiction. Psychological capital and self-control play important mediating roles in the relationship between the family environment and short video addiction. Enhancing adolescents’ psychological capital and self-control abilities can effectively prevent and intervene in addiction issues.

School bullying is a widespread phenomenon affecting a considerable proportion of adolescents worldwide, yet the relationship between school bullying and loneliness has received little attention. The aim of the present study was to understand the relationship between experiencing school bullying and loneliness among adolescents and to explore the role of social connectedness and parental support in this dynamic. We used cluster sampling to select 1277 students between grades 7 and 12 in four middle schools across two cities in Sichuan Province, China. Data were collected via questionnaires and analysis was conducted using descriptive statistics, chain mediation model tests, and moderation model tests. We found that bullying was significantly positively correlated with adolescent loneliness (r = 0.55, P < 0.001). Additionally, social connectedness played a mediating role between bullying and adolescent loneliness (effect size 51.57%). After controlling for gender, age, and household registration type, parental support moderated the relationship between bullying and loneliness among adolescents (β=−0.05, P < 0.01). As the level of parental support increased, the positive predictive effect of bullying on loneliness weakened significantly, although this moderating effect was not significant among participants who were not “left-behind” children. The study findings confirmed the relationship between school bullying and loneliness and revealed the internal logical relationship among social connectedness, parental support, loneliness, and school bullying. Our findings are valuable in preventing the negative effects of school bullying on left-behind children.