An ERP Study On Implicit Self-positivity Bias And Its Variability

People have a need for positive self-evaluation which differs among cultures. Based on previous researches, event-related potential (ERP) technology and Chinese personality-trait adjectives were used under prime paradigm to investigate the mechanism and neural basis of the implicit self-positivity bias about Chinese individuals in collectivism culture. Evaluative conditioning (EC) and intelligence feedback were applied to explore the variability and the effect of changes about implicit self-positivity bias. There are five experiments in this study.Experiment1investigated the mechanism and neural basis of implicit self-positivity bias with prime paradigm. The results showed shorter reaction time, smaller N2and N400amplitudes, as well as decreased activity in the prefrontal cortex (PFC) for information within the implicit self-positivity bias (self-positive and other-negative words) as compared to information outwith the bias (self-negative and other-positive words). The implicit self-positivity bias was comfirmed at both behavioral and electrophysiological levels, which works by associating self with positive evaluation and others with negative evaluation. The increased activity in PFC for self-negative information supported Moran’s functional processing hierarchy for self-relevant and emotional information.Experiment2observed a strengthened implicit self-positivity bias after subliminal evaluative conditioning with self-positive and other-negative word pairs. The results showed that participants in evaluative condition group responded faster to information within the implicit self-positivity bias, with smaller N400amplitudes and no activity in the PFC, when compared to this information in control group. The found indicated that implicit self-positivity bias had variability and was sensitive to experimental conditions, whose magnitude could be strengthened by intensifying self-positive and other-negative attitude. This kind of EC treatment might be a valid method for understanding the formation and development to the implicit self-positive attitude.Experiment3observed a diminished implicit self-positivity bias after subliminal evaluative conditioning with self-negative and other-positive word pairs. Participants in evaluative condition group had no remarkable diversity in reaction time or ERP data when processed information within or outwith the implicit self-positivity bias. The results revealed an increased activity in PFC for both kinds of information; particularly for information outwith the implicit self-positivity bias. It was possible that the increased activity in PFC was due to the threat to self-concept by the EC treatment, and then individuals recruited more cognitive resources to deal with the processing of self-referential information afterwards. The found indicated that implicit self-positivity bias had variability and could be diminished by intensifying self-negative and other-positive attitude. The diminished implicit self-positivity bias could help individuals avoid negative influence from self-expansion or overconfidence on important decisions.Experiment4inspected the effects that self-positive and other-negative EC treatment strengthened implicit self-positivity bias under negative intelligence feedback. The results still showed implicit self-positivity bias for participants in negative intelligence feedback group, and indicated that the effect of this EC treatment was stable enough to fend against the negative influence of negative intelligence feedback. The results supported the hypothesis of maintaining a positive self-concept in self-enhancement model, self-verification theory and self-evaluation maintainance model.Experiment5inspected the effects that self-negative and other-positive EC treatment diminished implicit self-positivity bias under positive intelligence feedback. The results revealed that implicit self-positivity bias recovered after positive intelligence feedback, which indicated an unstable effect for this EC treatment. Individuals showed implicit self-positivity bias again once they received positive feedback from the conditions. The results conformed to the hypothesis of maintaining a whole positive self-evaluation dynamically in self-affirmation theory.Taken together, there is an implicit self-positivity bias in Chinese individuals, and it works by associating self with positive evaluation and others with negative evaluation. The remarkable activity in PFC for self-referent information especially for self-negative information is the neural basis of this bias. The implicit self-positivity bias has variability and could be strengthened or diminished by evaluative conditioning (EC). The effect of change under EC treatment depends on if it contributes to maintain individuals’positive self-evaluation. When EC treatment enhanced its magnitude, the implicit self-positivity bias will not be eliminated even individuals receive negative intelligence feedback. When EC treatment diminished the bias, it will recover as soon as individuals receive positive intelligence feedback. In a word, the processing of self-referent information keeps a biased orientation to maintain individuals’positive self-evaluation and shows self-positivity bias.