听觉失匹配负波反映自动加工──感觉道间选择性注意时的新证据

为考察听觉失匹配负波是否反映自动加工，实验改进了视觉和听觉刺激同时呈现的感觉道间选择性注意实验模式，更好地控制了非注意听觉条件。结果发现，在注意与非注意听觉条件下，听觉偏离刺激均诱发出失匹配负波；注意听觉刺激时１４０－１８０ｍｓ的偏离相关负波与非注意时该时程负波的平均波幅之间无显著差异，而注意时１８０－２２０ｍｓ的偏离相关负波的平均波幅大于非注意时同一时程之负波；非注意听觉时失匹配负波的平均波幅和峰潜伏期不受视觉道任务难度的影响，该结果为听觉失匹配负波反映自动加工的观点提供了进一步证据。

AUDITORY MISMATCH NEGATIVTY REFLECTS AUTOMATIC PROCESS:EVIDENCE FROM INTERMODAL SELECTIVE ATTENTION PARADIGM

In order to testify the automaticity of auditory mismatch negativity,a renewed intermodal paradigm of selective attention in which visual and auditory stimuli were presented simultaneously was used in the present study so as to control the unattended condition better. The results showed that auditory MMN was elicited whether the auditory stimuli were attended or not and when attended, the mean amplitude during 140-180ms was equal to that of the unattended, the mean amplitude during 180-220ms was larger than that of the unattended. It was also found that the mean amplitude and peak latency of auditory MMN was not modulated by the degree of task difficulty of visual modality. Therefore, further evidence of the automaticity of auditory MMN was found in this experiment.