Background: This study aimed to explore relationships between impulsivity, interpersonal relationships, depression, and Internet Gaming Disorder (IGD) symptoms. Methods: A total of 118 young adults participated in this study: 67 IGD patients who met five or more of the DSM-5 diagnostic criteria for IGD and 56 healthy controls. We administered questionnaires to assess IGD symptoms (Young’s Internet Addiction Test; Y-IAT), impulsivity (Barratt Impulsiveness Scale; BIS-11), interpersonal relationship (Relationship Change Scale; RCS), and depression (Beck Depression Inventory; BDI). We used PROCESS macro in SPSS to perform mediation analysis. Results: IGD symptom was positively related to depression and impulsivity, and negatively related to the quality of interpersonal relationships. Mediation analysis revealed full mediation effects of interpersonal relationships and depression on the association between impulsivity and IGD symptoms in the IGD group. Specifically, even after adjusting for gender as a covariate, high impulsivity was associated with greater difficulty with interpersonal relationships; which further affected depression and increased the risk of IGD. Conclusions: These results demonstrate the importance of early intervention in IGD patients, particularly in young adults with high impulsivity. When intervening in adults’ IGD, we should consider not only individual factors (e.g., depression) but also socioenvironmental factors (e.g., interpersonal relationships).

Aims: The present study investigated neural connectivity associated with treatment responses in patients with Internet gaming disorder (IGD) using resting-state electroencephalography (EEG) coherence analyses.Methods: We included 30 patients with IGD and 32 healthy control subjects (HCs). Of the IGD patients, 18 completed an outpatient treatment that included pharmacotherapy with selective serotonin reuptake inhibitors for 6 months. Resting-state EEG coherence and self-report questionnaires were used to evaluate clinical and psychological features pre- and post-treatment, and data were analyzed using generalized estimating equations.Results: Compared with HCs, patients with IGD showed increased beta and gamma intrahemispheric coherence and increased delta intrahemispheric coherence of the right hemisphere at baseline. After 6 months of outpatient management, patients with IGD exhibited improvements in IGD symptoms compared with baseline, but they continued to show increased beta and gamma intrahemispheric coherence compared with that of HCs. No significant EEG coherence changes between the pre- and post-treatment assessments were detected in any band in the IGD group.Conclusion: These findings suggest that significantly greater intrahemispheric fast-frequency coherence may be an important neurophysiological trait marker of patients with IGD.

The Munich Chronotype Questionnaire (MCTQ) uses sleep behavior to assess chronotype, but the extent to which such sleep behavior based assessments might be useful in populations with sleep disorders, such as insomnia, is currently unclear. We thus systematically assessed sleep disorders, MCTQ and the Morningness-Eveningness Questionnaire (MEQ), another behavioral preferencebased assessment of chronotype, in 310 individuals. In a smaller substudy (n = 121), we compared the MCTQ to sleep diaries in insomnia patients and good sleepers. Insomnia patients had overall lower consistency in chronotypes compared to good sleepers on the MCTQ compared to the MEQ, which was also evident when compared to sleep diaries. As insomnia disorder is characterized by time gaps spent awake during the night due to difficulty maintaining sleep, there may be limitations in using mid-sleep time as an accurate indicator of chronotype in insomnia patients. Our study suggests that the MCTQ should be used in conjunction with another existing questionnaire or assessment tool when assessing chronotype in insomnia patients.

The increased prevalence of Internet Gaming Disorder (IGD) and the inclusion of IGD in DSM-5 and ICD-11 emphasizes the importance of measuring and describing the IGD symptoms. We examined the psychometric properties of the Diagnostic Interview for Internet Addiction (DIA), a semi-structured diagnostic interview tool for IGD, and verified the application of DIA in clinical practice for Korean adolescents. The DIA is conducted in a manner that interviews both adolescents and their caregivers, and each item has a standardized representative question and various examples. It consists of 10 items based on the DSM-5 IGD diagnostic criteria, which is cognitive salience, withdrawal, tolerance, difficulty in regulating use, loss of interest in other activities, persistent use despite negative results, deception regarding Internet/games/SNS use, use of Internet/games/SNS to avoid negative feelings, interference with role performance, and craving. The study included 103 adolescents divided into three subgroups (mild risk, moderate risk, and addicted group) based on the total score of DIA. Demographic and clinical characteristics were compared among the DIA subgroups using the chi-square test and analysis of variance (ANOVA), and correlation analysis was used to examine the associations of IGD symptoms with clinical variables (e.g., impulsivity, aggression, depression, anxiety, self-esteem). The DIA total score was significantly correlated with Internet and smartphone addiction, depression, state anxiety, self-esteem, impulsivity, aggression, and stress. Furthermore, the moderate risk and addicted group showed significantly higher levels of Internet and smartphone addiction, anxiety, depression, impulsivity, aggression, stress, and lower self-esteem compared with the mild risk group. The Junior Temperament and Character Inventory (JTCI), which measures temperament and character traits, revealed that the mild risk group had higher levels of persistence and self-directedness than did the addicted group. Our findings confirmed the psychometric properties of DIA and the application of the DIA classifications in Korean adolescents.

ObjectiveThe present study aimed to validate a Korean version of the self-report Depressive Symptom Inventory-Suicidality Subscale (DSI-SS).Methods553 South Korean undergraduate students (aged 18–34 years, 74.8% females) completed questionnaires. Participants completed Korean versions of the self-report Depressive Symptom Inventory-Suicidality Subscale (DSI-SS), Beck Depression Inventory-II (BDI-II), Insomnia Severity Index (ISI), Beck Scale for Suicide Ideation (BSS), and a measure of suicide-related symptom history.ResultsResults indicated that the DSI-SS demonstrated excellent internal consistency (α=0.93) and strong convergent validity with the BDI (r=0.57, p<0.01), ISI (r=0.27, p<0.01), and BSS (r=0.70, p<0.01). DSI-SS scores also significantly differentiated between those reporting a history of suicide attempts compared to non-suicide attempters [t (38.80)=-3.28, p<0.05].ConclusionGiven the brevity of this measure, and evidence for its validity, the Korean version of the DSI-SS may be particularly promising for clinical and empirical use as a screening tool among South Korean undergraduates.