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本实验采用了视听双通道伪同时呈现的ｏｄｄｂａｌ模式，以汉字和简单几何图形为视觉刺激，１０００Ｈｚ和８００Ｈｚ的纯音为听觉刺激，使用注意通道（注意和非注意条件）×刺激概率（偏差刺激概率均为１５％，标准刺激的概率均为８５％）的２×２因素设计，来研究视觉和听觉偏差刺激在注意和非注意条件下诱发的事件相关电位（ＥＲＰｓ）。实验中视觉和听觉刺激随机序列地呈现给被试（刺激间隔ＩＳＩ为７００～１３００ｍｓ），被试被要求注意某一通道如视觉通道，而相应地忽视另一通道即听觉通道，以左右手触键反应，如左手反应视觉偏差刺激，右手反应视觉标准刺激。结果表明，听觉偏差刺激在注意和非注意条件下均诱发了类似的不匹配负波（ＭＭＮ）；而视觉偏差刺激在注意和非注意条件下没有诱发ＭＭＮ或类似ＭＭＮ的成分，这是因为视觉系统的平行加工特性和难以对视觉影像产生记忆痕迹。听觉偏差刺激在注意条件下重迭了Ｎ２ｂ成分并跟随了Ｐ３ａ成分，这种重迭和跟随反映了选择注意中的定向反应。注意条件下听觉和视觉的偏差刺激诱发了较大波幅的Ｐ３００成分，反映了工作记忆中的表象更新。本实验的结果支持Ｎａａｔａｎｅｎ对ＭＭＮ所做的观察，听觉偏差刺激所诱发的ＭＭＮ与注意条件的无关性反映?
In this experiment, the oddbal mode of audio-visual dual-channel pseudo-simultaneous presentation was used, with Chinese characters and simple geometry as visual stimuli, 1000Hz and 800Hz pure tones as auditory stimuli, and attention channel (attention and non-attention conditions) × stimulus probability Both were 15% and the standard stimulus was 85%) were used to study the event-related potentials (ERPs) induced by both visual and auditory stimuli during attention and non-attentional conditions. In the experiment, visual and auditory stimuli were presented to the subjects randomly (stimulation interval ISI was 700 ~ 1300 ms). The subjects were asked to pay attention to a certain channel, such as the visual channel, while ignoring the other channel, the auditory channel, Reactions, such as left-handed responses to visual deviation stimuli, right-handed responses to visual standards stimuli. The results showed that auditory deviation stimuli induced similar mismatch negative waves (MMN) both in attention and non-attention conditions; whereas visual bias stimuli did not induce MMN or MMN-like components in both attentive and unnoticeable conditions because visual The parallel processing characteristics of the system make it difficult to create memory traces of visual images. Auditory bias stimuli overlap the N2b component and follow the P3a component under the condition of attention, which overlap and follow reflects the directional response in the selection note. Note that auditory and visual deviation stimuli induce a greater amplitude of P300 components, reflecting the appearance update in working memory. The results of this experiment support the observation made by Naatanen on MMN. The MMN induced by auditory deviation stimuli has nothing to do with the attentional condition.