An EEG Study On Self Positive Bias

The basic cognitive processes in both self-relatedness evaluation and others' mind representation include three stages: perception of social targets, integration of perceptions and memory, and evaluation. The three components, P200, N400 and LPP, are well-established indices of neural and cognitive resource allocation during the three kinds of cognitive processes of perception, integration and evaluation. Four event-related potential (ERP) experiments on self- and other-evaluation, with a 2 (Referential: Self vs Other)×2 (Valence: Positive vs Negative) design, were conducted, in which self-referential effect paradigm was conducted to examine the positive bias of self-evaluation. In Experiment 1, pronouns were primes. In Experiment 2, adjectives were primes. In Experiment 3 and 4, pronouns and adjectives were presented simultaneously with subjects instructed to judge on them in Experiment 3 and to only watch them in Experiment 4. Effects were found in the present study which investigated the positive bias of self-evaluation using SRE via ERP during three cognitive processes of self-evaluation. Firstly, RT indicated that subjects responded faster to positive self-referential words than to words under other conditions. Secondly, in perception stage, effects showed that positive other referential (vs negative other referential) stimuli and negative self referential stimuli (vs positive self referential) enhanced the amplitude of P200. In integration stage, effects reflected that positive other referential stimuli (vs negative other referential stimuli) and negative self referential stimuli (vs other referential stimuli) augmented the amplitude of N4. Still effects in evaluation stage demonstrated that positive self referential stimuli (vs positive other referential stimuli) elicited larger amplitudes of LPP, which was consistent with the effect of RT. Thirdly, these effects occurred either in overt evaluation or in covert evaluation conditions. We suggested that all these interactions should be the reflection of the positive bias of self-evaluation.