The Neural Mechanism Of Social Comparison And Its Influence Factors

Social comparison is a common phenomenon in human life.In our real life,people often define their social characteristics(such as ability,income,mood and health,etc),not purely depend on the objective criteria but also by comparing with others who are around them.That is to say,people obtain their meaning in a social environment.The comparisons between individuals with others,to some extent,have determined people's self-concept,the state of mood and the expectation for the future.Therefore,comparing with others have been an indispensable part in our life.Considering to the national conditions,we are affected by the traditional culture with the ?moderation? thinking for a long history.There is a special comparison in our real life-?worse off than some,better off than many?,which shows the Chinese characteristic."Moderation" is one of the nature for Chinese people.Based on the traditional difference between relative and absolute,upward comparison,downward comparison and parallel comparison," worse off than some,better off than many " includes the attitude of "Moderation" so that a complex social comparison is more ecologically effective.This study focused on the neural mechanism can provide a better understanding of the nature of the "Moderation".In addition,"Moderation" is not only reflected in the choice of comparative direction,there is a "degree" of the problem.Life provides us with endless opportunities for social comparison,but we can't connect all the information with us,therefore,it is not surprising that one of the basic premise in the study of social comparison is that people are selective in social comparison activities.Some people prefer to compare more with others,while someone prepare not to or less to comparison.This individual difference of social comparison orientation is common to be seen in our life.The introduction of individual difference in the social comparison orientation provide more information to the function of social comparison process.Individuals are no longer considered to be only compared to others,but there is some individual difference in the frequency.This individual difference may affect the reactions to others' emotions and behaviors,also may improve their predictability.Therefore,considering the individual difference of social comparison is not only have a significant impact on the theory of social comparison,but also influence the slef-evaluation and emotional response of social comparison.Even though some reasearchers explored the reason for social comparison orientation,both from the initial motivational factors and the current theory of information discrepancy.They were only exteral descriptions of phenomena,it is still unclear that the neural mechanisms of relevant factors affect social comparison.With the intensification of social competition,it has become an increasing psychological problem during the process of social comparison.Thus,to study systematic the neural mechanism of social comparison has important theory and reality significance for interpreting the bias of social comparison,relationship between different types of social comparison and self-evaluation?subjective well-being and emotional experience in our real life.Study 1 analyzed the neural mechanism in the process of social comparison.In the experiment 1,We used the ?guess-feedback-reward-evaluation? paradigm,simulated three subjects(one "true" subject and two other ?pseudo? subjects)to complete a point estimation task so that created a complex comparative situation.According to the feedback of accuracy of this task,we provided the reward information of true subject and two others' simultaneously(comparative information including "expectation congruent" when true subject was "correct" and received reward,"expectation incongruent" meaned true subject was "correct" but did not receive reward).The dynamic time course of the brain was recorded and analyzed by Event-Related Brain Potential(ERP)during the same feedback of accuracy but with different rewards,we explored the neural process in the complex social comparison.Results showed that the "expectation incongruent" generated a more positive late component of P3(P400-700)than "expectation congruent",together with the dipole source result(Posterior Cingulate Cortex,PCC)indicated that individuals even in the complex social contexts,when they faced the comparative information at first sight,would show the monitor and control of expectation.During the late stage of comparison,the difference of N1000-1500 between the "expectation incongruent" and "expectation congruent" as well as the dipole source result(Parahippocampal gyrus)revealed the expectation violate would produce an unpleased emotion.In the experiment 2,during the complex comparative situation(especially during the "expectation congruent"),in order to explore the neural mechanism of true subject(you:he/she: he/she)under different comparative directions(totally upward comparison 1:2:2;partial upward comparison 1:2:3;totally downward comparison 2:1:1;partial downward comparison 3:2:1,parallel comparison 1:1:1 and ?worse off than some,better off than many? 2:1:3).We used the paradigm of three people by Functional magnetic resonance imaging(fMRI)with high spatial resolution and analyzed the brain activation of different comparative directions.Results showed that the downward comparison and ?worse off than some,better off than many? showed stronger activation in ventral striatum than upward comparison,while there was no difference between downward comparisons and ?worse off than some,better off than many?,totally upward comparison showed no difference from partial upward comparisons.These might indicate people could satisfy in ?worse off than some,better off than many? like downward comparison.Downward comparisons showed significantly activation in medial frontal gyrus than upward comparison,partial downward comparison activated more in frontal pole cortex than ?worse off than some,better off than many?,but ?worse off than some,better off than many? showed more stronger activation in frontal pole cortex than totally upward comparison,and the signal in frontal pole cortex had a significant negative correlation with the social adaptation scores,which indicated people might moderate the reward circuit and convert values during this special comparison,thus the less activation in the frontal pole cortex could make people adapt the social better.In general,together with the results of ERP and fMRI showed that expectation violated make people experienced unpleased emotion.?Worse off than some,better off than many? could help people change their comparison from upward comparison to downward comparison and had the same reward experience as downward comparison.In summary,during the dynamic processing,posterior cingulate cortex,parahippocampal gyrus,ventral striatum,frontal pole cortex and medial frontal gyrus might be the key hubs during complex social comparison.People were easily failed during upward comparison leading to negative emotion,while there might be a mechanism for regulating stress during ?worse off than some,better off than many? so that people could reply the unpleased emotions induced by upward comparison.Study 2 examined the neural basis of the individual difference in social comparison orientation.We explored the neural basis of social comparison orientation as a stable trait based on a large sample(>350)by using the structural magnetic resonance imaging(sMRI)and the resting-state functional magnetic resonance imaging(resting-state fMRI)which are not affected by the experimental tasks and materials.These technologies can reflect the neural basis of individual difference.In the experiment 3 with structural data,we found that the gray matter volume in parahippocampal positively correlated with the social comparison orientation,which might mean people with high social comparison orientation have more negative emotional experience and memories.In the Experiment 4,functional data showed the fractional amplitude of low frequency fluctuation(fALFF)in insula and the functional correlation between parahippocampal gyrus and posterior cingulate cortex positively correlated with the social comparison orientation,which indicated people defined their characteristics by comparing with others,people with higher uncertain feelings probably were more likely compare with others.With the importance of the reliability of the results in the field of cognitive neuroscience,we further verified the stability of the neural basis of social comparison orientation.Experiment 5a,we used another new sample with 153 undergraduate students to verify the stabiliy of the neural basis of social comparison orientationin in the experiment 3.The results showed that the gray matter volume of Parahippocampal gyrus still significantly positively correlated with social comparison orientation in the new sample,which might mean the gray matter volume of Parahippocampal gyrus was the stable neural basis of social comparison orientation.In consideration of the relationship between the social comparison and depression,in the experienment 5b,we analyzed the influence of the neural mechanism of social comparison on the depression.We used the automatic thoughts which is a cognitive part of the depression as an effective standard to verify the validation of the neural basis of social comparison by using mediation analysis.Results showed that the gray matter volume of parahippocampal gyrus could affect the automatic thoughts by social comparison orientation.According to the result,we confirmed that people who had stronger negative emotional experience or memories probably prefered to engage in more social comparison so that to obtain information about themselves by comparing with others.This process would make individuals with high social comparison orientation tend to have more negative automatic thoughts.These results suggested that excessive social comparison would have the potential costs of depression.Study 3 examined the neural mechanism of how the related personality traits and environmental factors influence social comparison.In the experiment 6,we explored the neural mechanism of how the related personality traits including self-consciousness,personality and empathy influenced social comparison.We found that the public self could have an impact on the social comparison by the gray matter volume in parahippocampal gyrus and the fractional amplitude of low frequency fluctuation in insula.These results further showed the important role of public self-consciousness in the influence on the neural mechanism of social comparison based on the previous papers which only found there might a closer relationship between self-consciousness and social comparison.People with higher public self-consciousness,which means care more about how the public and others think about them,would easily generated more negative emotional experience or memories and uncertain feeling so that showed a higher social comparison orientation.Additionally,we found the perspective taking as a cognitive part of the empathy could also predict social comparison by the gray matter volume in parahippocampal gyrus.People with higher perspective taking means higher empathy to others,could easily prefer to more social comparison by the mediator of the gray matter volume in parahippocampal gyrus.Actually,we further found the neuroticism moderated the neural mechanism of social comparison by interacting with the gray matter volume in parahippocampal gyrus.Combining all these results showed that the public self-consciousness and empathy could have a direct influence on the social comparison,especially the high public self and high perspective taking might be the risk factors of high social comparison orientation.The neuroticism could limit the relationship between the gray matter volume in parahippocampal gyrus and social comparison.Only the scores in neuroticism below 162 could find the significant correlations between the gray matter voulume in parahippocampal gyrus and social comparison,while higher than the score could not find the effect.In the experiment 7,we explored the neural mechanism of how family environment influenced the social comparison,we found expressiveness in the family environment could impact on the social comparison by the mediator(the gray matter volume in parahippocampal gyrus).More negative expressiveness family would make people have more negative emotional experience or memories,which would lead individuals prefering to more social comparisons.Based on all the results mentioned above,we firstly used the ERP and fMRI to explore the dynamic neural mechanism of complex social comparison situation with ?worse off than some,better off than many?,further revealed the neural basis of the stable social comparison orientation based on a large sample(>350)by combing the structural and functional data,then investigated the neural mechanism of how the related personality traits and environmental factors influence social comparison.Based on the previous studies,we further explored the neural mechanisms in the complex social comparison situation,and found out the neural basis of the stable social comparison orientation.We provided the possible model for the important related personality traits and environmental factors for the application of social comparison.This study supplied more evidence for the neural mechanism of social comparison theoretically.In the application,we offered the possible theoretical basis and practical guidance for the effective predict and control the social comparative behaviors which would improve the mental health.