关键词: 完整线索, 自我优势效应, 漂移扩散模型, 事件相关电位

Abstract: The Complete Self: Shape Completeness Enhances Self-Prioritization Abstract Self-relevant information plays a crucial role in human survival and development. Previous studies have shown that the congruence between the metaphorical meaning of a stimulus and the self-concept can facilitate the processing of self-related information, suggesting that self-cognition may be shaped and activated through metaphorical associations in dynamic environmental contexts. In Chinese cultural contexts, completeness is often associated with integrity, unity, and perfection, providing a meaningful metaphorical background for examining how concrete perceptual features may be related to abstract self-cognition. However, it remains unclear whether complete shapes, as concrete perceptual symbols, can enhance the processing advantage of self-related information through metaphorical associations. Therefore, the present study examined whether shape completeness can influence self-prioritization in perceptual decision-making. We hypothesized that associations between the self-label and complete shapes would receive preferential processing, forming a self-complete association advantage. The present study consisted of two experiments. Experiment 1 adopted a 2 (Shape Completeness: complete, incomplete) × 2 (Encoding: self-related, stranger-related) × 2 (Match Type: match, mismatch) within-subjects design, combining hierarchical drift diffusion modeling and event-related potential techniques to investigate the influence of complete shapes on self-related processing and its cognitive and neural mechanisms. Participants completed a perceptual matching task consisting of two phases. In the associative phase, they learned associations between two geometric shapes, namely complete and incomplete shapes, and two identity labels, namely self and stranger. In the subsequent shape–label matching phase, participants judged whether each presented shape–label pair matched the learned association. Thirty-five college students participated in Experiment 1, and valid data were obtained from thirty participants, including twenty-two females and eight males. EEG data were recorded from 64 electrode sites according to the international 10–20 system. The ERP components N1, P2, N2, early LPP, and late LPP were analyzed as indices of different stages through which complete shapes influence self-related processing. Experiment 2 adopted a between-subjects manipulation of the identity–shape association rule. Under the condition without rule reversal, each participant received only one fixed identity–shape association, thereby excluding the possible interference caused by rule switching. The behavioral results of Experiment 1 showed a stable self-prioritization effect: compared with stranger-related associations, self-related associations were associated with faster reaction times, higher accuracy, greater perceptual sensitivity, and lower response criteria. In addition, a completeness advantage was observed, as complete-shape associations were processed more efficiently than incomplete-shape associations. More importantly, under the correct matching condition, self-complete associations showed faster reaction times, higher accuracy, and lower response criteria than both stranger-complete and self-incomplete associations, indicating a specific processing advantage for self-complete associations. The hierarchical drift diffusion modeling results further showed that this self-complete association advantage was supported by a faster information accumulation rate and a shorter non-decision time. The ERP results showed that, compared with self-incomplete and stranger-complete associations, self-complete associations elicited smaller N1 amplitudes at 80–130 ms and smaller N2 amplitudes at 250–350 ms, as well as larger early LPP amplitudes at 450–650 ms. Considering that the N1 effect may be jointly influenced by block mapping rules and condition-related factors, the N1 result was interpreted cautiously as an early processing difference related to self-complete associations. Experiment 2 showed that the self-complete association advantage still existed when the association rule was not reversed, suggesting that this effect was not caused by switching costs induced by rule changes. Overall, the results indicate that self-prioritization is not only reflected in the general preferential processing of self-related stimuli but is also modulated by the congruence between stimulus features and the self-concept. Complete-shape information enhanced the processing priority of self-related associations, suggesting that complete shapes may facilitate self-related processing by increasing the compatibility between perceptual completeness and the self-concept. Within the cultural context in which completeness is associated with integrity, unity, and perfection, the self-complete association may reflect individuals’ tendency to integrate completeness-related meanings into self-processing. This effect was supported by behavioral, diffusion-modeling, and ERP evidence, suggesting that the self-complete association advantage involves faster evidence accumulation, reduced non-decision processing time, early processing differences, and enhanced later attentional integration. Keywords: completeness cue; self-prioritization effect; drift diffusion model; ERPs

Key words: completeness cue, self-prioritization effect, drift diffusion model, ERPs