Background High-speed train engineers' lower extremities are constrained by compulsive vigilance pedal tasks and limited space beneath the control console during driving. Shifts in alertness triggered by running route observation may share the same mental resource required by moderate-to-low physical exertion. Current research on improving cab design and maintaining optimal on-duty attention allocation remains limited. Objective To examine variations in lower extremity muscle load, gaze-tracking behavior, and driving performance under various combinations of vigilance pedal positions and route scenarios during simulated high-speed train tasks. To identify optimal working condition combinations that promote level and variety of physical activity and facilitate rational attention allocation. Methods A 4×2 within-subjects design were employed (4 vigilance pedal position profiles: knee front, side, and any; 2 route scenarios: monotonous and complex). Nine male college volunteers were recruited as simulated drivers to perform designated interval driving tasks. Surface electromyography and eye tracking were used to assess leg muscle load and gaze behavior respectively. Task performance and subjective fatigue were recorded. Results In all simulation driving tasks, skeletal muscle loads were low with the percentage of maximum voluntary contraction (%MVC) at approximately 4%. No fatigue tendencies were observed within single trial blocks (7 min), and the subjective fatigue ratings remained relatively low. While the activation of the dominant-side tibialis anterior was higher for the knee pedal than for the front (%MVC: 3.7% ± 3.13% vs. 1.08% ± 0.72%) or the side pedals (%MVC: 3.7% ± 3.13% vs. 1.4% ± 0.77%). The activation level of the dominant-side gastrocnemius was higher for the knee pedal than for the other three pedal profiles. For the any pedal condition, the intercept of the instantaneous median frequency curve for the dominant-side rectus femoris was lower in the monotonous route than in the complex route [(111.18 ± 35.78) Hz vs. (153.33 ± 39.12) Hz]. Among eye-tracking metrics, total fixations were higher during knee-level pedaling than side pedaling, while more saccades were recorded in monotonous routes than in complex ones. Regarding task performance, the any pedal yielded fewer missed signals than the front pedal, with 2/3 and 1/3 of participants preferring the front and knee pedals, respectively. The activation levels of the dominant tibialis anterior and dominant gastrocnemius muscles during the knee pedal × complex route combination were higher than any combination involving the front pedal. No statistically significant effect of pedal position or route scenario was found on other indicators. Conclusion The combination of knee pedal and complex route provides an optimal working setting for maximizing leg muscle mobility without compromising attention allocation or driving performance. It is recommended that train engineers modulate attention during monotonous routes to avoid emotional tension and increased muscle strain caused by over-monitoring. Given the ergonomic characteristics of high cognitive load, low physical exertion levels, and highly restricted lower limb mobility among high-speed train engineers, future cab designs should consider incorporating knee-level vigilance pedal and adjust safety alertness rules to allow reset via either front or knee pedal.

Background High-speed train engineers' lower extremities are constrained by compulsive vigilance pedal tasks and limited space beneath the control console during driving. Shifts in alertness triggered by running route observation may share the same mental resource required by moderate-to-low physical exertion. Current research on improving cab design and maintaining optimal on-duty attention allocation remains limited. Objective To examine variations in lower extremity muscle load, gaze-tracking behavior, and driving performance under various combinations of vigilance pedal positions and route scenarios during simulated high-speed train tasks. To identify optimal working condition combinations that promote level and variety of physical activity and facilitate rational attention allocation. Methods A 4×2 within-subjects design were employed (4 vigilance pedal position profiles: knee front, side, and any; 2 route scenarios: monotonous and complex). Nine male college volunteers were recruited as simulated drivers to perform designated interval driving tasks. Surface electromyography and eye tracking were used to assess leg muscle load and gaze behavior respectively. Task performance and subjective fatigue were recorded. Results In all simulation driving tasks, skeletal muscle loads were low with the percentage of maximum voluntary contraction (%MVC) at approximately 4%. No fatigue tendencies were observed within single trial blocks (7 min), and the subjective fatigue ratings remained relatively low. While the activation of the dominant-side tibialis anterior was higher for the knee pedal than for the front (%MVC: 3.7% ± 3.13% vs. 1.08% ± 0.72%) or the side pedals (%MVC: 3.7% ± 3.13% vs. 1.4% ± 0.77%). The activation level of the dominant-side gastrocnemius was higher for the knee pedal than for the other three pedal profiles. For the any pedal condition, the intercept of the instantaneous median frequency curve for the dominant-side rectus femoris was lower in the monotonous route than in the complex route [(111.18 ± 35.78) Hz vs. (153.33 ± 39.12) Hz]. Among eye-tracking metrics, total fixations were higher during knee-level pedaling than side pedaling, while more saccades were recorded in monotonous routes than in complex ones. Regarding task performance, the any pedal yielded fewer missed signals than the front pedal, with 2/3 and 1/3 of participants preferring the front and knee pedals, respectively. The activation levels of the dominant tibialis anterior and dominant gastrocnemius muscles during the knee pedal × complex route combination were higher than any combination involving the front pedal. No statistically significant effect of pedal position or route scenario was found on other indicators. Conclusion The combination of knee pedal and complex route provides an optimal working setting for maximizing leg muscle mobility without compromising attention allocation or driving performance. It is recommended that train engineers modulate attention during monotonous routes to avoid emotional tension and increased muscle strain caused by over-monitoring. Given the ergonomic characteristics of high cognitive load, low physical exertion levels, and highly restricted lower limb mobility among high-speed train engineers, future cab designs should consider incorporating knee-level vigilance pedal and adjust safety alertness rules to allow reset via either front or knee pedal.

BackgroundWith the rapid development of the networking technologies， internet addiction has increasingly become a serious mental health issue. Previous studies have revealed the link between childhood trauma and internet addiction， while the mediating role of perceived stress in this link is not yet clear. ObjectiveTo investigate the role of medical students' perceived stress in the relationship between childhood trauma and internet addiction， so as to provide references for the intervention of internet addiction. MethodsFrom February to March 2023， a random sampling technique was used to select 1 232 undergraduate students from the School of Clinical Medical Sciences of Southwest Medical University as research subjects. The Childhood Trauma Questionnaire-Short Form （CTQ-SF）， Perceived Stress Scale （PSS）， Internet Gaming Disorder Scale （IGDS）， and Bergen Social Media Addiction Scale （BSMAS） were used for assessment. Pearson's correlation coefficients were calculated. The mediation effect of perceived stress in the relationship between childhood trauma and internet addiction was tested using Model 4 in the SPSS Process 4.1， and Bootstrapping procedure involving 5 000 replicates was employed to confirm the statistical significance. ResultsA total of 1 016 （82.47%） valid completed questionnaires were gathered. The CTQ-SF scores of medical students were positively correlated with PSS scores， IGD scores， and BSMAS scores （r=0.583， 0.474， 0.465， P<0.01）. PSS scores were positively correlated with IGD scores and BSMAS scores （r=0.369， 0.479， P<0.01）. Childhood trauma in medical students was found to positively predict perceived stress （β=0.191， P<0.01）， social media addiction （β=0.160， P<0.01）， and internet gaming disorder （β=0.106， P<0.01）. Perceived stress played a significant mediating role in the relationship between childhood trauma and internet gaming disorder， indirect effect value was 0.018 （95% CI： 0.009~0.027）， accounting for 16.98%. Perceived stress also exhibited a significant mediating role in the relationship between childhood trauma and social media addiction， indirect effect value was 0.063 （95% CI： 0.048~0.079）， accounting for 39.38%. ConclusionChildhood trauma in medical students may affect internet gaming disorder and social media addiction through perceived stress. ［Funded by 2022 Annual Research Project of Sichuan Applied Psychology Research Center，（number，CSXL-22102）］

BackgroundPatients with depressive disorder often exhibit impaired decision-making functions. However， the relationship between decision-making abilities and depressive and anxiety symptoms in these patients remains unclear. ObjectiveTo explore the characteristics of decision-making behavior in patients with depressive disorder， and to analyze its relationship with clinical symptoms. MethodsA total of 48 patients diagnosed with depressive disorder according to the Diagnostic and Statistical Manual of Mental Disorders， fourth edition （DSM-IV） were recruited from the Department of Psychosomatic Medicine of the Affiliated Hospital of Southwest Medical University from October 2020 to May 2023. Concurrently， 52 healthy individuals matched for age and gender were recruited from Luzhou as the control group. Beck Depression Inventory （BDI） and Beck Anxiety Inventory （BAI） were used for assessment， and decision-making behavior was evaluated using Probabilistic Reversal Learning （PRL） task. Indicators assessed included the number of trials to criterion， perseverative errors， win-stay rate and lose-shift rate. Spearman correlation analysis was used to assess the correlation between BDI and BAI scores and PRL task indicators. ResultsThe depression group showed a significantly higher lose-shift rate compared with the control group （t=3.684， P<0.01）. There were no statistically significant differences between two groups in trials to criterion， perseverative errors and win-stay rate （t=0.329， 0.132， 0.609， P>0.05）. In depression group， BDI and BAI scores were positively correlated with the win-stay rate（r=0.450， 0.398， P<0.01）. ConclusionPatients with depressive disorder are more likely to change their decision-making strategies following negative outcomes. Furthermore， the severity of depressive and anxiety symptoms is associated with a greater propensity to maintain existing decisions after receiving positive feedback. ［Funded by 2019 Joint Project of Luzhou Science and Technology Bureau-Southwest Medical University （number， 2019LZXNYDJ39］

Objective To Investigate the efficacy of modified electroconvulsive therapy(MECT)in patients with schizophrenia across different genders.Methods From May 2018 to August 2022,481 patients with schizophrenia were recruited from three psychiatric hospitals in Luzhou,Zigong,and Yibin.According to gender grouping,both groups received adjunctive MECT treatment for two consecutive weeks for a total of six treatments.The differences in positive and negative syndrome scale(PANSS)scores before and after treatment,UKU adverse reaction rating scale(UKU),and gastrointestinal symptom rating scale(GSRS)scores were compared between the two groups.Results After quality control,463 cases were followed up for analysis including 246 males and 217 females.Compared with pre-treatment,the total PANSS score and scores on each subscale were significantly reduced in both genders after treatment(P<0.001).When comparing the reduction rates between the groups,the male patients showed a higher reduction rate in negative symptoms than the female patients(31.24%±30.24%vs.25.80%±33.96%,P<0.05).However,there were no significant differences between the two groups in the reduction rates of the total score,positive symptoms,and general psychopathology(P>0.05).The comparison of adverse reactions showed that the frequency of other types of adverse reactions was higher in female patients than in male patients(47.47%vs.37.80%,P<0.05).However,no significant differences were observed in the adverse reactions related to the mental,neurological,autonomic nervous system,and gastrointestinal systems(P>0.05).Correlation analysis revealed that the reduction rate of the PANSS total score was positively correlated with smoking history(r=0.135,P=0.034)and alcohol history(r=0.160,P=0.012)in male patients,while the reduction rate of the PANSS total score was negatively correlated with the disease duration(r=-0.210,P=0.002)and positively correlated with the age of onset(r=0.145,P=0.032)in female patients.Conclusion MECT is significantly effective for both male and female patients with schizophrenia.Compared to female patients,MECT shows a more pronounced effect on negative symptoms in male patients.Additionally,the factors related to the efficacy of MECT differ between genders,indicating that it is necessary to consider the clinical characteristics of patients comprehensively when selecting an MECT treatment plan.

Objective To Investigate the efficacy of modified electroconvulsive therapy(MECT)in patients with schizophrenia across different genders.Methods From May 2018 to August 2022,481 patients with schizophrenia were recruited from three psychiatric hospitals in Luzhou,Zigong,and Yibin.According to gender grouping,both groups received adjunctive MECT treatment for two consecutive weeks for a total of six treatments.The differences in positive and negative syndrome scale(PANSS)scores before and after treatment,UKU adverse reaction rating scale(UKU),and gastrointestinal symptom rating scale(GSRS)scores were compared between the two groups.Results After quality control,463 cases were followed up for analysis including 246 males and 217 females.Compared with pre-treatment,the total PANSS score and scores on each subscale were significantly reduced in both genders after treatment(P<0.001).When comparing the reduction rates between the groups,the male patients showed a higher reduction rate in negative symptoms than the female patients(31.24%±30.24%vs.25.80%±33.96%,P<0.05).However,there were no significant differences between the two groups in the reduction rates of the total score,positive symptoms,and general psychopathology(P>0.05).The comparison of adverse reactions showed that the frequency of other types of adverse reactions was higher in female patients than in male patients(47.47%vs.37.80%,P<0.05).However,no significant differences were observed in the adverse reactions related to the mental,neurological,autonomic nervous system,and gastrointestinal systems(P>0.05).Correlation analysis revealed that the reduction rate of the PANSS total score was positively correlated with smoking history(r=0.135,P=0.034)and alcohol history(r=0.160,P=0.012)in male patients,while the reduction rate of the PANSS total score was negatively correlated with the disease duration(r=-0.210,P=0.002)and positively correlated with the age of onset(r=0.145,P=0.032)in female patients.Conclusion MECT is significantly effective for both male and female patients with schizophrenia.Compared to female patients,MECT shows a more pronounced effect on negative symptoms in male patients.Additionally,the factors related to the efficacy of MECT differ between genders,indicating that it is necessary to consider the clinical characteristics of patients comprehensively when selecting an MECT treatment plan.

Objective: The nine diagnostic criteria for Internet Gaming Disorder (IGD) proposed in Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) have been widely adopted, but have also faced significant criticism. This study evaluated the psychometric properties of the nine DSM-5 criteria for IGD using item response theory (IRT). Methods: Four DSM-5-based scales, including the Game Addiction Scale, the Internet Gaming Disorder Scale Short-Form, the Ten- Item Internet Gaming Disorder Test, and the Internet Gaming Disorder Scale, were administered to 1,530 Chinese adolescents and young adults. IRT models were used to assess the psychometric properties of these criteria. The potential for differential item functioning (DIF) related to sex and between adolescents and adults was also evaluated. Results: All nine DSM-5 criteria demonstrated very high to perfect discrimination (a >1.38), providing substantial diagnostic information (item information >0.476) for diagnosing IGD. These scales, despite variations in wording and scoring methods, exhibited strong correlations in total scores (r≥0.502, p<0.001) and high consistency (Kendall’s W ≥0.656, p<0.05) concerning the fitted IRT parameters. Among the nine criteria, escape showed the lowest cross-scale discrimination, item information, and difficulty. In contrast, withdrawal showed the highest item information and discrimination, and the second highest difficulty. Additionally, there was no evidence of DIF related to sex or age (adolescents vs. adults) across nearly all scale items. Conclusion These findings indicate that the nine DSM-5 criteria generally possess acceptable psychometric properties for diagnosing IGD. Notably, withdrawal may represent a core symptom of IGD. Conversely, escape demonstrated inferior performance compared to the other eight criteria, indicating a potential need for further revision.

Objective: Previous research has explored a variety of mental disorders associated with Internet Gaming Disoder (IGD) and Social Media Addiction (SMA). To date, few studies focused on the network characteristics and investigated mood and sleep symptoms across SMA and IGD of adolescence at a group-specific level. This study aims to identify different characteristics of IGD and SMA and further determine the group-specific psychopathology process among adolescents. Methods: We conducted a cross-sectional study to recruit a cohort of 7,246 adolescents who were scored passing the cutoff point of Internet Gaming Disorder Scale-Short Form and Bergen Social Media Addiction Scale, as grouped in IGD and SMA, or otherwise into the control group. Patient Health Questionnaire-9, Generalized Anxiety Disorder 7-item, and Pittsburgh Sleep Quality Index were assessed for the current study, and all assessed items were investigated using network analysis. Results: Based on the analytical procedure, the participants were divided into three groups, the IGD group (n=789), SMA group (n=713) and control group (n=5,744). The edge weight bootstrapping analysis shows that different groups of networks reach certain accuracy, and the network structures of the three groups are statistically different (pcontrol-IGD=0.004, pcontrol-SMA<0.001, pIGD-SMA<0.001). The core symptom of SMA is “feeling down, depressed, or hopeless”, while IGD is “feeling tired or having little energy”. Conclusion Although IGD and SMA are both subtypes of internet addiction, the psychopathology processes of IGD and SMA are different. When dealing with IGD and SMA, different symptoms should be addressed.

Objective: Self-determination theory (SDT) deems that people have three causality orientations: autonomy orientation, control orientation, and impersonal orientation. Previous studies suggested that lower autonomy orientation or higher control and impersonal orientations may be associated with more addictive behaviors. Our study aimed to investigate if these associations exist in Internet gaming disorder (IGD), and if sensation seeking, anxiety, and depression could influence the associations between causality orientations and IGD symptoms. Methods: A total of 1,400 college students completed the Internet Gaming Disorder Scale, General Causality Orientation Scale, Brief Sensation Seeking Scale, Generalized Anxiety Disorder Scale, and Patient Health Questionnaire. Correlation, multiple linear regressions, structural equation model (SEM) analyses, and moderation analyses were conducted to explore the associations. Results: The control and impersonal orientations were positively associated with IGD symptoms, while the autonomy orientation was negatively associated with them. Moreover, SEM analyses showed that the autonomy-IGD relationship was totally mediated by anxiety and depression, the impersonal-IGD relationship was partially mediated by anxiety, and the control-IGD relationship was partially mediated by depression. Finally, the effects of causality orientations on IGD were moderated by sensation seeking. Conclusion Overall, autonomy orientation is linked to fewer gaming problems, whereas control and impersonal orientations are associated with more gaming problems. Moreover, the relationships between causality orientations and IGD symptoms are mediated by anxiety and depression and moderated by sensation seeking. Our findings inform theory on the motivations of gaming behaviors and may shed light on the prevention and intervention of IGD from the perspective of SDT.

Objective: Self-determination theory (SDT) deems that people have three causality orientations: autonomy orientation, control orientation, and impersonal orientation. Previous studies suggested that lower autonomy orientation or higher control and impersonal orientations may be associated with more addictive behaviors. Our study aimed to investigate if these associations exist in Internet gaming disorder (IGD), and if sensation seeking, anxiety, and depression could influence the associations between causality orientations and IGD symptoms. Methods: A total of 1,400 college students completed the Internet Gaming Disorder Scale, General Causality Orientation Scale, Brief Sensation Seeking Scale, Generalized Anxiety Disorder Scale, and Patient Health Questionnaire. Correlation, multiple linear regressions, structural equation model (SEM) analyses, and moderation analyses were conducted to explore the associations. Results: The control and impersonal orientations were positively associated with IGD symptoms, while the autonomy orientation was negatively associated with them. Moreover, SEM analyses showed that the autonomy-IGD relationship was totally mediated by anxiety and depression, the impersonal-IGD relationship was partially mediated by anxiety, and the control-IGD relationship was partially mediated by depression. Finally, the effects of causality orientations on IGD were moderated by sensation seeking. Conclusion Overall, autonomy orientation is linked to fewer gaming problems, whereas control and impersonal orientations are associated with more gaming problems. Moreover, the relationships between causality orientations and IGD symptoms are mediated by anxiety and depression and moderated by sensation seeking. Our findings inform theory on the motivations of gaming behaviors and may shed light on the prevention and intervention of IGD from the perspective of SDT.