Discipline of Psychology, College of Science, Health, Engineering and Education, Murdoch University, Perth, WA, Australia.
Institute of Psychology, Leipzig University, Leipzig, Germany.
Psychophysiology. 2020 Jun;57(6):e13576. doi: 10.1111/psyp.13576. Epub 2020 Apr 15.
Research shows that the visual system monitors the environment for changes. For example, a left-tilted bar, a deviant, that appears after several presentations of a right-tilted bar, standards, elicits a classic visual mismatch negativity (vMMN): greater negativity for deviants than standards in event-related potentials (ERPs) between 100 and 300 ms after onset of the deviant. The classic vMMN is contributed to by adaptation; it can be distinguished from the genuine vMMN that, through use of control conditions, compares standards and deviants that are equally adapted and physically identical. To determine whether the vMMN follows similar principles to the auditory mismatch negativity (MMN), in two experiments we searched for a genuine vMMN from simple, physiologically plausible stimuli that change in fundamental dimensions: orientation, contrast, phase, and spatial frequency. We carefully controlled for attention and eye movements. We found no evidence for the genuine vMMN, despite adequate statistical power. We conclude that either the genuine vMMN is a rather unstable phenomenon that depends on still-to-be-identified experimental parameters, or it is confined to visual stimuli for which monitoring across time is more natural than monitoring over space, such as for high-level features. We also observed an early deviant-related positivity that we propose might reflect earlier predictive processing.
研究表明，视觉系统会监控环境变化。例如，在呈现几个向右倾斜的条形标准刺激后，出现一个向左倾斜的条形变异性刺激，会引发经典的视觉失匹配负波（vMMN）：在变异性刺激出现后 100 到 300 毫秒的事件相关电位（ERP）中，变异性刺激的负性比标准刺激更大。经典的 vMMN 是由适应引起的；通过使用控制条件，可以将其与真正的 vMMN 区分开来，真正的 vMMN 比较的是适应程度和物理特征相同的标准刺激和变异性刺激。为了确定 vMMN 是否遵循与听觉失匹配负波（MMN）相似的原则，我们在两项实验中搜索了来自简单、生理上合理的刺激的真正 vMMN，这些刺激在基本维度上发生变化：方向、对比度、相位和空间频率。我们仔细控制了注意力和眼动。尽管有足够的统计能力，我们仍然没有发现真正的 vMMN 的证据。我们得出的结论是，真正的 vMMN 是一种相当不稳定的现象，取决于尚未确定的实验参数，或者它仅限于视觉刺激，因为在时间上进行监控比在空间上进行监控更自然，例如对于高级特征。我们还观察到了一个早期的变异性相关正波，我们认为它可能反映了早期的预测处理。
