关键词: 个体时间自我评价, 集体时间自我评价, 时间自我参照范式, 事件相关电位

Abstract:

Both behavioral and electrophysiological studies have demonstrated the future positive bias of individual temporal self-evaluation. However, the characteristic of collective temporal self-evaluation is still an open question. The present study aimed to investigate the similarities and differences between individual and collective temporal self-evaluation using a temporal self-reference paradigm among Chinese undergraduates. In comparison to Westerners, Chinese are more unified in their self-concept, and their temporal self contains more social, relational, and family selves in the context of collectivist culture. Therefore, it was assumed that the collective temporal self-evaluation might be highly similar to individual temporal self-evaluation across time, according to interdependent self-construal theory.

The present study adopted a 3 (time dimension) × 2 (reference object) × 2 (valence) within-subjects design and employed an event-related potential (ERP) technique to explore the individual and collective temporal self-evaluation using two experiments. Brain electrical activity was recorded from 64 scalp sites using tin electrodes mounted in an elastic cap according to the international 10-20 system, and late positive components (LPC) were used as the EEG indicators because LPC was closely related to temporal self-evaluation. In Experiment 1, 30 Chinese undergraduates were recruited, and they were asked to evaluate their and Zhangsan’s past self, present self, and future self (“Zhangsan” was often referred to the name of an ordinary person in China), using positive and negative personality adjectives. In Experiment 2, 23 Chinese undergraduates were recruited to assess past self, present self, and future self of Chinese and Americans.

In Experiment 1, the behavioral results showed that participants tended to use more positive adjectives and fewer negative adjectives to evaluate their future self, compared to their past self and present self; They tended to use more negative adjectives to evaluate their past self, compared to their present self. In addition, participants tended to use more positive adjectives and fewer negative adjectives to evaluate their future self, compared to Zhangsan’s self. These behavioral results indicated that individual self-evaluation was positive across time and had a trend to increase from past to future. ERP data showed that negative adjectives evoked greater LPC amplitudes than positive adjectives in the tasks of evaluating past self and present self, while there was no significant difference in the evaluation of future self, which demonstrated more “negativity bias” effects in individual past self-evaluation and present self-evaluation, compared to individual future self-evaluation. In Experiment 2, the behavioral results showed that participants tended to use more positive adjectives and fewer negative adjectives to evaluate collective temporal self than non-collective temporal self. The positive attitudes toward collective temporal self were no significant differences between different temporal dimensions (past, present, and future), indicating that participants had a stable and consistent positive bias toward their collective temporal self. ERP data showed that greater LPC amplitudes were evoked for negative adjectives than positive adjectives in evaluating collective past self and present self, while there was no significant difference in evaluating collective future self, which indicated that participants had more “negativity bias” effects in collective past self-evaluation and present self-evaluation, compared to collective future self-evaluation.

In conclusion, our study suggested that both individual self-evaluation and collective self-evaluation had a positive bias across time. Moreover, there existed a “negativity bias” effect at the neurophysiological level in individual self-evaluation and collective self-evaluation. These results demonstrated that individual temporal self-evaluation and collective temporal self-evaluation among Chinese college students had similar cognitive and neurophysiological characteristics, to some extent, providing supporting evidence for the theory of interdependent self-construal.

Key words: individual temporal self-evaluation, collective temporal self-evaluation, temporal self-reference paradigm, event-related potential