Abstract: 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.

Key words: Mismatch negativity(MMN), Automatic process, Event-related potentials(ERPs)