采用视听觉的跨通路刺激实验模式,通过对ERP实验数据的分析发现:在非注意条件下,顶叶和颞叶的负电位波形不规则,且一致性差;而额叶及枕叶(接近视觉初级投射区)均出现了较明显的视觉早期偏差相关负成分,其潜伏期范围在140~170ms之间,存在通道特异性,与听觉MMN类似。据此得出:视觉早期偏差相关负成分应该是由视觉通路痕迹产生的视觉MMN;视觉早期偏差相关负成分的源有两个,一个位于额叶,另一个位于初级视皮层所在的枕叶处。
Mismatch negativity (MMN) in the visual modality is currently a focus in many related areas. In our work, this problem is explored through an ERP experiment in cross-modal stimulating pattern. The result shows that an obvious negativity component related with primary, visual deviant exists at the frontal and occipital lobes on the condition of non-attention. Similar to auditory. MMN, this negativity has a latent period of 140- 170 ms and also a modality specificity. Then it is reasonable to conclude that this negativity is a visual MMN from the memory model of visual modality with two sources-one at the frontal lobe but the other at the occipital lobe's primary visual cortex.