Abstract：
Previous studies have proposed two cognitive mechanisms responsible for the Ebbinghaus illusion effect, i.e., contour interaction and size contrast. However, the neural underpinnings of these two mechanisms are largely unexplored. The present study introduced binocular depth to the Ebbinghaus illusion configuration and made the central target appear either in front of or behind the surrounding inducers in order to disturb size contrast instead of contour interaction. The results showed that the illusion effect, though persisted, was significantly reduced under the binocular depth conditions. Notably, the target with a larger perceived size reduced early alpha-band power (8-13 Hz, 0-100 ms after stimulus onset) at centroparietal sites irrespective of the relative depth of the target and the inducers, with the parietal alpha power negatively correlated with the illusion effect. Moreover, the target with a larger perceived size increased the occipito-parietal beta-band power (14-25 Hz, 200-300 ms after stimulus onset) under the no-depth condition, and the beta power was positively correlated with the illusion effect when the depth conditions were subtracted from the no-depth condition. The findings provided neurophysiological evidence in favor of the two cognitive mechanisms of the Ebbinghaus illusion by revealing that early alpha power is associated with low-level contour interaction and late beta power is linked to high-level size contrast, supporting the claim that neural oscillations at distinct frequency bands dynamically support different aspects of visual processing.
摘要：
以前的研究提出了两种负责艾宾浩斯错觉效应的认知机制，即，轮廓相互作用和尺寸对比。然而,这两种机制的神经基础在很大程度上尚未被探索。本研究将双眼深度引入了Ebbinghaus错觉配置，并使中心目标出现在周围诱导物的前面或后面，以干扰尺寸对比度而不是轮廓相互作用。结果表明,错觉效应,虽然坚持,在双眼深度条件下显着降低。值得注意的是,具有较大感知尺寸的目标降低了早期α波段功率(8-13Hz，刺激开始后0-100ms）在中心顶叶部位，无论目标和诱导物的相对深度如何，顶叶α功率与错觉效应负相关。此外，具有较大感知尺寸的目标增加了枕顶β波段功率(14-25Hz，刺激开始后200-300ms）在无深度条件下，当从无深度条件中减去深度条件时，β功率与错觉效应呈正相关。通过揭示早期α功率与低水平轮廓相互作用相关，晚期β功率与高水平尺寸对比度相关，这些发现提供了有利于艾宾浩斯错觉的两种认知机制的神经生理学证据。支持不同频段的神经振荡动态支持视觉处理的不同方面的说法。
