Behavior And Brain Imaging Study Of The Effect Of Overt Narcissism On The Negative Physical Self

Overt narcissism is a personality trait that has a grandiose view of the self and maintains this self-representation through self-enhancement,which has more adaptive components than covert narcissism.Negative physical self refers to individuals’ negative cognition and evaluation of their own body image.Exploring the factors that influence the negative physical self is imperative,for which will bring forth numerous adverse outcomes.Studies have shown that personality will have an impact on negative physical self.As a personality factor,the relationship between overt narcissism and negative physical self is still unclear.Only a few studies have found a controversial relationship between overt narcissism and negative physical self,and most of these studies only pay attention to a certain dimension of body image.Therefore,whether overt narcissism can affect negative physical self needs to be further studied.Previous studies have suggested that examining the neurobiological processes behind personality can help to understand the mechanism by which the personality acts as a risk or protective factor.Exploring the link between overt narcissism and its neural basis and a negative physical self may aid in comprehending the mechanism in which overt narcissism impacts a negative physical self.Currently,a few studies have explored the neural basis of overt narcissism,but the number of participants is small and the results are unstable.In addition,there are no studies exploring the neural basis of overt narcissism affecting negative physical self.Based on the findings and limitations of previous studies,this study proposes to investigate the following two questions:(1)At the behavioral level,whether overt narcissism can negatively predict negative physical self as a protective factor.(2)At the neural level,structural and restingstate brain imaging techniques were used to investigate the neural basis of overt narcissism and its correlation to a negative physical self.At the behavioral level,this study explored the effect of overt narcissism on negative physical self using questionnaires and experimental manipulation.In study 1,a questionnaire survey was used to explore the relationship between overt narcissism and various dimensions of negative physical self in a large sample(N=1759).The results indicated that there was a significant negative correlation between overt narcissism and negative physical self on the general appearance and facial appearance dimensions.Furthermore,regression analysis revealed that overt narcissism still negatively predicted general appearance and facial negative physical self,even after controlling for gender,age and body mass index(BMI).Study 2 explored the effect of overt narcissism on the negative body self through experimental manipulation using a recall priming paradigm.Subjects were separated by randomization into the priming group(n=138)and the control group(n=140)to complete questionnaire measurements and experimental tasks for their respective groups.Independent sample T-test results showed that the overt narcissism score of the priming group was significantly higher than that of the control group after the completion of the manipulation task,indicating that the manipulation of overt narcissism in this study was effective.To further explore the differences between groups in terms of negative physical self,a covariance analysis was employed.The results showed that the general appearance and facial negative physical self of the priming group were significantly lower than those of the control group.Correlation and regression analyses indicated that overt narcissism score,which was measured after the manipulation task,negatively predicted general appearance and facial negative physical self.At the neural level,this study investigated the effects of overt narcissism and its neural basis on negative physical self.In study 3,structural MRI was used.Gray matter volume(GMV)was selected as the analysis index.The correlation between overt narcissism score and GMV was analyzed in a large sample(N=1643),and the mediating model of overt narcissism → brain →negative physical self was further constructed according to the key brain regions found in the whole-brain correlation.The results showed that overt narcissism was significantly positively correlated with GMV in the right middle temporal gyrus(MTG).In addition,GMV in the right MTG partially mediated the effect of overt narcissism on general appearance and facial negative physical self.In study 4,resting-state f MRI was used.Fractional amplitude of low frequency fluctuations(f ALFF)and functional connectivity(FC)were selected as analysis indexes.In a large sample(N=1647),a whole-brain correlation analysis was conducted between overt narcissism scores and resting spontaneous brain activity and FC.Then a mediating model of overt narcissism → brain →negative body self was established based on significant brain regions and FC.The results showed that overt narcissism was significantly positively correlated with f ALFF in the left insula,left precentral gyrus(Pre CG)and bilateral superior temporal gyrus(STG).Moreover,FC analysis was conducted using brain regions significant in whole-brain correlation analysis in study 3 and study 4as seed.The results showed that overt narcissism was significantly positively correlated with right STG–Pre CG connectivity,and also was significantly positively correlated with functional connections between the left STG and posterior cingulate gyrus(PCC),the left orbitofrontal cortex(OFC),the right inferior frontal gyrus(IFG)and the right thalamus(THA).The results of mediating analysis showed that f ALFF in the left Pre CG and functional connection between right STG and right Pre CG partially mediated the effects of overt narcissism on general appearance and facial negative physical self,respectively.In conclusion,this research has the following contributions:(1)At the behavioral level,we found that overt narcissism negatively predicts general appearance and facial negative physical self,and tested this finding for the first time using an experimental manipulation paradigm.(2)This study provides fresh evidence for the neural basis of overt narcissism by using structural and resting-state analysis in a large sample.This study is the first to find the relationships between overt narcissism and the MTG,STG and Pre CG,which are involved in self-reference processing,positive self-evaluation and social cognition.In addition,the relationships between the connectivity strength of STG–Pre CG,STG–IFG,and STG–THA and overt narcissism score were also found for the first time in this study.The functional connectivity of these regions may represent the characteristics of self-regulation mode combined with interpersonal and intra-personal,response inhibition ability and dominance pursuit in high overt narcissists.(3)This study is the first to investigate the influence of overt narcissism and its neural basis on negative physical self in a large sample,and found that overt narcissism can indirectly affect negative physical self by causing changes in neural structure and function.The MTG associated with the positive bias of self-focus is the common neural basis for overt narcissism influencing the general appearance and facial negative physical self.The f ALFF in the left Pre CG involved in self-attention and body assessment and STG–Pre CG connectivity which represented the interpersonal and intra-personal regulation patterns are the neural basis of the influence of overt narcissism on the general appearance and facial negative physical self,respectively.These findings provide neural evidence for a protective effect of overt narcissism on body image.Overall,our findings add to the positive function of overt narcissism and enrich the research on the impact of personality elements on the negative physical self.The study of the recall priming paradigm and the discussion of the neural basis may provide a new basis for the intervention of the negative physical self in the future.