Abstract: The self-reference effect is the enhanced speed and quality of processing and memorization observed with respect to information that is related to the individual’s self-concept. According to the preceding research, self-reference effect have the different with degree, and different degree of intimacy with the core self. Then, the brain on the depth of its reference treatment is different, also. Highly self-relevant stimulus will get faster response compared with minimally self stimulate in the brain. This is called the degree of self-reference processing effect. On the basis of summarizing the preceding research, this study uses the event related potential technology, through ERPs experiments investigation the degree of special subjects of self-reference processing effect and neural mechanisms. Experiment adopted three kinds of classic oddball models, using an implicit way to investigate the extraversion individual self-reference processing degree effect. Used three-character non-name lexical phrases served as the standard stimulus, and a three-character non-lexical phrase served as target stimuli. Six categories of stimuli were used in a three-stimulus oddball paradigm. Three sets of self-relevant stimuli, the non-self-relevant stimulus, and two filler stimuli, served as distracters. The name of the participant was used as the highly self-relevant stimulus, the name of participant’s father as the moderately self-relevant stimulus, the name of China’s leaders the minimally self-relevant stimulus, and the name of the president of the United States, served as the non-self-relevant stimulus. All names are three Chinese characters long. Familiarity was equivalent (see below) across all sets of stimulus names. All name stimuli were made into images on a PC using Microsoft Office Picture Manager. Image size, word length, and complexity were matched across the name conditions. Experiment found that on the P2 amplitude, highly self-related stimuli of electrode at front and central and front -central position induced greater P2 amplitude than other stimulation. On the latent period of P2, the electrode in the front, central, and parietal position, highly self-related to stimulate induced the short incubation period than other stimulation. In N2 amplitude, highly self-related name induced larger P2 amplitude than other stimulus in the left brain; comparing introversive subjects, control group subjects of highly self-relevant names induced larger amplitude of N2 than other stimulation. On the latent period of N2, highly self-relevant stimuli in the whole brain induced the short latent period of N2, it is better than other stimulation, and the central-parietal position of the electrode is the shortest possible; Highly self-relevant name of two types of personality subjects induced shorter incubation period of N2 than other stimulation, but control group subjects is the shortest. On average amplitude of P3, highly self-relevant stimuli in whole brain induced the P3 amplitude is bigger than other stimulation. The effect of midline brain regions is largest. Research results show that self-reference processing with the degree of effect is actually existence, highly self-relevant stimuli will get deeper and exquisite processing than moderately and minimally self-relevant stimuli. Comparison control group individuals, introversion subject was weaker in the degree of self-reference processing effect. And in early stage, highly self-relevant stimuli of control group individuals will be faster being noticed than minimally self-related stimuli by the brain. In the late stage of cognitive, highly self-relevant stimuli will get deeper and elaborating processing.

Key words: Introverted, Self-reference effect, Degree effect, Event-related potential, N2, P3

摘要： 采用事件相关电位技术和三类刺激的经典oddball范式，以内隐的方式探讨内倾特质个体的自我参照加工程度效应及其神经机制。实验发现，在P2的波幅上，在电极前部、前中部和中部位置高自我相关的刺激比其它刺激诱发了更大的P2波幅。在P2的潜伏期上，在电极前部、中部、和中后部位置高自我相关的刺激比其它刺激诱发了更短的潜伏期。在N2的波幅上，高自我相关名字比其它刺激在左脑所诱发了更大的P2的波幅；对比内倾型被试，中间型被试的高自我相关名字比其它刺激诱发了更大的N2的波幅。在N2的潜伏期上，高自我相关的刺激在全脑都比其它刺激诱发了更短的N2潜伏期，且中后部电极位置的潜伏期最短；两类人格被试的高自我相关名字比其它刺激诱发了更短的N2潜伏期，但中间型人格被试的潜伏期最短。在P3平均波幅上，高自我相关的刺激在全脑都比其它刺激诱发了更大的P3波幅，其中中部脑区效应最大。研究结果表明内倾特质个体的自我参照加工具有程度效应，但对比中间型个体，内倾特质个体的自我参照加工的程度效应更弱。

关键词: 内倾, 自我参照加工, 程度效应, ERPs, N2, P300