The Influence Of Social Dominance Orientation On Mental Health And Its Potential Neural Mechanism

Social dominance orientation reflects the degree of an individual’s desire for obtaining a superior and dominant position in a hierarchical group,and it affects the individual’s attitudes and behaviors towards others in a society.People with high social dominance usually show superiority,dominance,and desire to have higher social status or power than others.However,how individuals’ SDO affect their emotional disorders remains unknown in youth.Forming hierarchy causes huge social stress which triggered the inevitable HPA responsivity and behavioral obstacles in low-ranking animals.How social stress impacts on the highranking animals hasn’t been fully studied.The current study includes two parts: Study 1 we recruited 521 college students(24.3 ± 1.73 years old)whose SDO and emotional disorders were determined by deploying the SDO and Symptom checklist-90(SCL-90),and the correlation between SDO and mental health were analyzed by using SPSS 22.0;Study 2 In order to clarify the neural mechanism of dominance-subordination social stress leading to anxiety,depression and other mental diseases,we established a social stress animal model by group housing 4 male and 2 female long-evans rats in a visible burrow system(VBS)(total,8 cohorts).Animals were administered either single or repeated VBS exposure,thereafter,the hypothalamus and brainstem neural mechanism were investigated by the in situ hybridization(ISH).The results showed:(1)There was a significant positive correlation between social dominance orientation and all mental disorders,including somatization(β = 0.205,t = 4.762,p < 0.001),obsessive-compulsive symptoms(β = 0.209,t = 4.855,p < 0.001),interpersonal sensitivity(β = 0.234,t = 5.479,p < 0.001),depression(β = 0.223,t = 5.202,p < 0.001),anxiety(β = 0.252,t = 5.915,p < 0.001),hostility(β = 0.223,t = 5.200,p < 0.001),phobia(β = 0.223,t = 5.212,p < 0.001),paranoia(β = 0.250,t = 5.886,p < 0.001),psychosis(β = 0.230,t = 5.378,p < 0.001)and the total score(β = 0.246,t = 5.772,p < 0.001).(2)The subordinate animals revealed increased PVH CRH m RNA expression and decreased NTS PPG m RNA expression when compared to the control and dominant rats during the first cycle of VBS challenge.The results indicated that subordinate animals might suffer more severe stress at the first VBS cycle during hierarchy establishment.The dominant animals showed elevated PVH CRH m RNA expression and declined NTS PPG m RNA transcription after repeated VBS exposure.Maintaining a dominant position in a repeatedly exposed VBS hierarchy stimulated a hyperactivated CRH response to enormous stress in dominant animals.Furthermore,the subordinate rats reduced PVH AVP m RNA expression but increased NTS TH m RNA expression after experiencing 2 cycles of VBS housing.The results suggested that the NTS recruited a diversified regulatory capacity for both catecholamine and noncatecholamine neural pathways under social stress challenges.Conclusion: The college students with high SDO scores may risks higher chances for developing the mental vulnerabilities.Both dominant and subordinate animals may suffer from social stress challenges in a hierarchy society which lead to various emotional disorders underlying different neural mechanisms.