The Association between Default-mode Network Functional Connectivity and Childhood Trauma on the Symptom Load in Male Adults with Methamphetamine Use Disorder

Objective@#The relationship between adverse childhood experiences and methamphetamine use disorder (MUD) has been shown in previous studies; nevertheless, the underlying neural mechanisms remain elusive. Childhood trauma is associated with aberrant functional connectivity (FC) within the default-mode network (DMN). Furthermore, within the DMN, FC may contribute to impaired self-awareness in addiction, while cross-network FC is critical for relapse.We aimed to investigate whether childhood trauma was associated with DMN-related resting-state FC among healthy controls and patients with MUD and to examine whether DMN-related FC affected the effect of childhood trauma on the symptom load of MUD diagnosis. @*Methods@#Twenty-seven male patients with MUD and 27 male healthy controls were enrolled and completed the Childhood Trauma Questionnaire. DMN-related resting-state FC was examined using functional magnetic resonance imaging. @*Results@#There were 47.1% healthy controls and 66.7% MUD patients in this study with adverse childhood experiences.Negative correlations between adverse childhood experiences and within-DMN FC were observed in both healthy controls and MUD patients, while within-DMN FC was significantly altered in MUD patients. The detrimental effects of adverse childhood experiences on MUD patients may be attenuated through DMN-executive control networks (ECN) FC. @*Conclusion@#Adverse childhood experiences were negatively associated with within-DMN FC in MUD patients and healthy controls. However, DMN-ECN FC may attenuate the effects of childhood trauma on symptoms load of MUD.

The Interaction of Oxytocin and Social Support, Loneliness, and Cortisol Level in Major Depression

OBJECTIVE: Loneliness is a specific risk factor for depressive symptoms and suicidal behavior. The present study examined whether the serum oxytocin level would interact with social support and buffers loneliness and hypothalamic-pituitary-adrenal (HPA)-axis activity in drug-naïve patients with major depressive disorder (MDD). METHODS: Twenty-six patients with MDD (male:female = 3:23; mean age, 45.54 ± 12.97 years) were recruited. The 17-item Hamilton Depression Rating Scale, UCLA Loneliness Scale and self-reported Measurement of Support Function Questionnaire were administered. Serum oxytocin and cortisol levels were assessed using a commercial immunoassay kits. RESULTS: In MDD patients, a negative association was found between degrees of social support and loneliness (β = −0.39, p = 0.04). The interaction between social support and serum oxytocin level was negatively associated with loneliness (β = −0.50, p = 0.017) and serum cortisol level (β = −0.55, p = 0.020) after adjusting for age. Follow-up analyses showed that the association between higher social support and lower loneliness was observed only in the higher-oxytocin group (r = −0.75, p = 0.003) but not in the lower group (r = −0.19, p = 0.53). The significance remained after further adjusting for sex and depression severity. CONCLUSION: Low oxytocin level is a vulnerability factor for the buffering effect of social support for loneliness and aberrant HPA-axis activity in MDD patients.