本研究将单纯呈现(mere exposure)范式与情感启动范式相结合，以汉语双字词为刺激材料，通过四个行为实验和一个脑电实验对刺激重复呈现后所具有的情感属性进行检验。实验一和二分别对标准的情感启动范式和单纯呈现范式进行验证，获得了显著的情感启动效价一致效应和单纯呈现效应，证明了这两种范式的有效性与可靠性，也验证了实验选用的刺激材料的适合性。实验三中以重复呈现过的中性词替换原标准情感启动范式中情感属性为积极的启动刺激，再次进行与实验一相同的情感启动测验，实验结果观察到了显著的情感启动效价一致效应，重复呈现后的中性词在充当积极情绪词运用于启动刺激时，同样能对随后出现的目标词产生影响：对积极效价的目标词产生促进作用，对消极效价的目标词产生抑制作用。实验四与实验三基本相同，不同之处在于虽采用实验三中的中性词充当启动刺激，但这些中性词事先未经过重复呈现，实验结果未观察到情感启动效价一致效应，进一步表明实验三中获得的情感启动效价一致效应并不是由这些中性词本身所引起，而是这些中性词经过重复呈现后获得了积极的情感属性，发挥了类似于积极情绪词所起的作用，重复呈现使这些中性词的情感属性发生了变化。研究认为，重复呈现使原本不具效价的中性刺激获得了积极的情感属性，且这一情感属性具有较好的稳定性与影响力。实验五采用事件相关电位(ERPs)实验考察重复呈现后的中性词诱发的神经电活动。实验中先重复呈现中性词，随后将它们与积极词、消极词混合呈现，要求被试判断屏幕上出现的词所具有的效价，实验结果发现，在刺激呈现后约200ms左右，重复呈现过的中性词引发的脑电波与积极词引发的脑电波更接近，相对地，与消极词及未重复呈现过的中性词的脑电波更远离，进一步证明了重复呈现后的中性词在情感属性上更接近于积极属性的情绪词。研究表明，刺激的重复呈现会导致偏好的产生，使其能够起到积极情感刺激的作用。刺激的重复呈现可能是积极情感产生的一个来源。

The aim of this study is to investigate the affective quality of the stimuli that have been exposed repeatedly and to find the relationship between mere exposure effect and the generation of positive affect. Mere exposure effect describes a phenomenon that repeated, unreinforced exposure to a stimulus is sufficient to enhance affect toward it. Affective priming effect means that participants need less time to evaluate a target stimulus if that target is preceded by a prime stimulus with the same valence compared to when the target stimulus is preceded by a prime stimulus with a different valence. Affective priming paradigm is sensitive to the valence of stimulus. In this study, through combine the mere exposure effect paradigm with affective priming paradigm, four behavioral experiments and one ERP experiment were operated to investigate the relationship between mere exposure effect and the generation of positive affect. A total of 89 undergraduate students participated. The materials were thirty positive, thirty negative and thirty neutral Chinese words which had been estimated on valence, frequency, and complexity. In experiment 1 and 2, the validity of standard affective priming paradigm and mere exposure effect paradigm were examined. In experiment 1, subjects have to finish a standard affective priming task, subjects responded to target words which follows prime words and mask stimulus and decided whether the target word is a positive word or a negative one. In mere exposure effect task, every neutral words had been presented 5 times and 33 ms every time , following the presentation, according to their liking, subjects would make a choice from one exposed word and one new word. Affective priming effect and mere exposure effect were obtained respectively in experiment 1 and 2. Results show that affective priming paradigm and mere exposure paradigm is valid and reliable, the stimulus material is suitable. In experiment 3, positive prime words in standard affective priming paradigm was replaced by repeated exposed neutral words which have been used in experiment 2, same to experiment 2, these neutral words have been exposed to subjects before affective priming task, significant affective priming effect obtained successfully in spit of this replacement. Namely, neutral words possessed positive valence after repeated exposure, the response of subjects to positive target words had been facilitated and response to negative target words been interfered. It played the roles of positive prime words which should to have in the standard affective priming paradigm. With these same neutral words, affective priming effect weren’t observed in experiment 4 when these neutral words weren’t exposed previously. Subjects’ reaction time needed to evaluate the target words as either “positive” or “negative” is not different whenever the prime words was “neutral” or “negative”, the result shows that neutral words can not generate affective priming effect by itself if they have not been exposed previously. In experiment 5, ERP technique has been used to investigate the nature of neutral words which been exposed on brain mechanism. Study showed that the waveform of repeated exposed neutral words more closer to the waveform of positive words in time window 180-250ms. These results demonstrated that the repeated exposure of stimuli could lead to the affective preference and this kind of preference could play the roles of positive emotional stimuli. This research suggested that the mere exposure of stimuli may be a source of the formation of positive affection.