选择一致性影响结果评价的ERP研究

本研究通过两个实验探讨了当被试主动做出与他人一致/不一致的选择行为(实验1)或看到他人做出与自己一致/不一致的选择行为(实验2)时,其选择行为的一致性是如何影响结果评价过程的。脑电数据表明在结果评价的早期阶段,无论被试是主动或被动地与他人做出相同选择,这种选择一致性都会放大输赢结果之间的差异:体现在选择一致情况下比不一致情况下诱发更大的d FRN。而在结果评价的晚期阶段,当被试先做出选择之后,看到他人做出与自己不一致的选择时(实验2),相比他人与自己选择一致时,诱发了更大的P3和LPP波幅。说明被试很可能把他人的不一致选择加工为一种冲突。因此投入了更多认知资源来加工这一结果。本研究是一个探索性的创新研究,首次从时间维度上分离了选择行为和结果反馈两个阶段,并提供了选择一致性对结果评价有影响作用的脑电证据。

Consistency of choice modulates outcome evaluation: Evidence from ERP studies

Previous studies have shown that outcome evaluation is sensitive to social influences. However, it remains unknown whether the consistency of choice between self and others also affect the outcome evaluation. To gain more insight in this research area, we designed two experiments in the present study, in which two participants (a real participant and a confederate) completed a gambling task together. In this task, the real participant chose from two options before/after the confederate made his/her choice. The outcomes of their choices revealed after both of their choices were made. According to the choosing scenario, 2 conditions were considered in the present study for both taking the same (consistent choices) or different options (inconsistent choices). Sixteen (7 males, 20.40 ± 1.11 y) and twenty (10 males, 22.21 ± 1.70 y) healthy adults participated in the experiment 1 and 2, respectively. With normal or corrected to normal vision, none of them reported any history of neurological diseases or brain injuries. Participants were asked to perform a gambling task in collaboration with another participant. By taking turns to choose one from two covered cards, they won 50 or 0 RMB depending on their choosing consistency. In the experiment 1, the confederate chose first while in the experiment 2 the real participant chose first. After both of them made their choices and were informed with the other's choice, the outcome were revealed, which fell in 4 categories of (i) both chose the same card and both won; (ii) both chose the same option and both lost; (iii) they chose different cards and the real participant won; and (iv) they chose different cards and the real participant lost. ERP results showed that in the early stage of outcome evaluation, no matter who chose first, a more pronounced dFRN was associated with participants taking the same option than taking different options. In the later stage of outcome evaluation, only in experiment 2, increased P3 and LPP were observed when their choices were the same than different. Our data suggests that the consistency of choices between self and other does modulate the neural activity of outcome evaluation. Specifically, in the early stage, consistent choices amplified the neural response to negative outcome as indicated by the enlarged dFRN. In the later stage, when the participant made the choice first and saw the other chose a different option, this inconsistency would trigger a sense of conflict, leading to more mental processes to avoid it later. This effect reflected in the enlarged amplitudes of P3 and LPP. Our finding provides some insights into how social context influences the psychophysiological processes of outcome evaluation.