The Relationship Between Behavioral Inhibition/Activation Systems And Non-suicidal Self-injury In Junior High School Students

ObjectivesThis study investigated the relationship between subcomponents of the behavioral inhibition/activation systems(BIS/BAS)and NSSI in junior high school students,and multigroup analysis of the mediating effects of depression based on different NSSI functions.MethodsUsing convenience and whole-group sampling methods,2900 junior high school students in Shandong Province were selected for the study in December 2021,and questionnaires were administered using the Adolescents Self-Harm Scale,Behavioral Inhibition/Activation Scales(BIS/BAS scales),and the Zung Self-Rating Depression Scale(SDS).A total of 2900 questionnaires were distributed in this study,and 2429 valid questionnaires were returned,with a valid return rate of 83.76%.The junior high school students with NSSI were divided into four groups according to functions:neither emotion management nor sensation seeking(A),mere emotion management(B),mere sensation seeking(C),and both emotion management and sensation seeking(D).Chi-square test was used to compare the detection as well as the function of NSSI by demographic group,independent-samples t-test was used to compare differences in the score of BIS/BAS subsacles and SDS between groups with and without NSSI,and ANOVA and post hoc comparisons of differences in the score of BIS/BAS subscales,SDS,and NSSI severity among junior high school students in different functional groups.In junior high school students with NSSI,Pearson’s correlation analysis and linear stepwise regression analysis were used to test the relationship between the sensitivity of BIS/BAS subscomponents,depression and NSSI.structural equation model was applied to test the mediating role of depression in the relationship between the sensitivity of BIS/BAS subcomponents and NSSI in junior high school students.Multigroup structural equation model was used to explore the differences between different functional groups.Results(1)The annual incidence of NSSI among junior high school students in Shandong Province was 37.54%(912/2429),with 84.98%(775/912)of those who repeatedly engaged in NSSI(≥2 times of NSSI)and 67.87%(619/912)of those who engaged in NSSI by more than one methods.Emotion management was the most dominant function of NSSI in this study(67.32%,614/912),and group B was the most dominant,accounting for 55.81%(509/912).The incidence of depression was 32.73%(795/2429),of which 69.69%(554/795),24.15%(192/795)and 6.16%(49/795)were mild depression,moderate depression and severe depression,respectively.Chi-square test showed that the incidence of NSSI was significantly different in different gender,grade,physical health status and development environment subgroups(P<0.05),but only the proportion of NSSI function groups differed between gender subgroups(P<0.001).where 64.41%(333/517)female junior high school students engaged in NSSI with a function of emotion management.(2)Independent-samples t-test revealed that NSSI junior high school students had higher sensitivity of BIS,BAS-Fun Seeking and more severe depression,while BAS-Reward Responsiveness sensitivity was lowert=5.084,which was statistically significant(P<0.001).ANOVA showed significant differences among the NSSI functional groups for the scores of BIS,BAS-Fun Seeking,SDS and NSSI severity(P<0.001),while the scores of BAS-Drive and Reward Responsiveness were not significantly different(P>0.05).Post hoc comparison revealed lower score of BIS in the group A and C,and higher score of BAS-Fun Seeking in group C and D.For SDS and NSSI severity,group B and D scored higher.(3)Pearson’s correlation analysis showed that sensitivity of BIS and BAS-Fun Seeking was significantly positively correlated with depression degree and NSSI severity,sensitivity of BAS-Reward Responsiveness was significantly negatively correlated with depression degree and NSSI severity,depression degree was positively correlated with NSSI severity,and sensitivity of each BIS/BAS subcomponent was positively correlated with each other,which was significant(P<0.001).Linear stepwise regression analysis showed a positive effect of depression degree on NSSI severity,a negative effect of BAS-Reward Responsiveness on NSSI severity,which was significant(P<0.001).A significant effect of gender and physical health status was found on NSSI severity(P<0.05).Sensitivity of BIS/BAS subcomponents served as input variables,NSSI severity served as an output variable,and depression severity served as a mediating variable.After controlling for gender and physical health status,structural equation model showed a good fit of the main model(χ2/df=1.204,GFI=0.998,AGFI=0.988,NFI=0.995,CFI=0.999,RMSEA=0.015).Depression played a completely mediating role between BIS and BAS-Fun Seeking and NSSI with completely mediating effect values of 0.126 and 0.08,and a partially mediating role between BAS-Reward Responsiveness and NSSI with a partially mediating effect value of-0.190,accounting for the total effect of 57.40%.All mediating effects were significant(P<0.001).(4)With the function of NSSI as the moderating variable,the multi group structural equation model showed that the comparison between the unconstrained model and the structural weights model,structural covariances model as well as structural residuals model did not pass the invariance test(P<0.001),indicating that the corresponding models for different functional groups differed significantly.In group A,depression played a partially mediating role between BAS-Fun Seeking and NSSI with a partially mediating effect value of 0.061,accounting for the total effect of 26.18%,and a completely mediating role between BIS and BAS-Reward Responsiveness and NSSI with completely mediating effect values of 0.060 and-0.091.In group B,depression played a partially mediating role between BAS-Reward Responsiveness and NSSI with a partially mediating effect value of-0.219,accounting for the total effect of 56.30%.and a completely mediating role between BIS and BAS-Fun Seeking and NSSI with completely mediating effect values of 0.123 and 0.078.In group C,depression played a completely mediating role between BAS-Fun Seeking as well as BAS-Reward Responsiveness and NSSI with completely mediating effect values of 0.121 and-0.102.In group D,depression played a completely mediating role between BIS,BAS-Drive,BAS-Fun Seeking as well as BAS-Reward Responsiveness and NSSI with completely mediating effect values of 0.110,0.107,0.103 and-0.102.All mediating effects were significant(P<0.05).Conclusions(1)The incidence of NSSI in junior high school students is relatively high,the proportion of repeated NSSI is high,and the methods are vavious.NSSI mainly functions as emotional regulation.Gender and physical health status are influencial factors for NSSI,and NSSI in female junior high school students more functions as emotion management.(2)Sensitivity of BAS-Reward Responsiveness is lower,whereas sensitivity of BIS as well as BAS-Fun Seeking is higher in junior high school students with NSSI than that in students without NSSI.Sensitivity of BAS-Fun Seeking is higher in junior high school students engaging in NSSI with function of sensation seeking,while sensitivity of BIS is lower in those engaging in NSSI without function of emotion management.Additionally,depression and NSSI are more severe in junior high school students with NSSI functioning as emotion management.(3)BIS and BAS-Fun Seeking indirectly positively affect NSSI through depression.BASReward Responsiveness not only directly negatively affects NSSI,but also has an indirectly negative effect on NSSI via depression.(4)The effects of BIS/BAS subcomponents on NSSI are different among groups of NSSI functions.BAS-Fun Seeking and BAS-Reward Responsiveness both affects NSSI through depression in all groups of NSSI functions.Only in the group of NSSI functioning as both emotion management and sensation seeking,BAS-Drive negatively affects NSSI through depression.Only in the group of NSSI functioning as sensation seeking,BIS has no effect on NSSI.