Ehinger Benedikt V, König Peter, Ossandón José P
Institute of Cognitive Science, University of Osnabrück, Osnabrück 49069, Germany, and
Institute of Cognitive Science, University of Osnabrück, Osnabrück 49069, Germany, and Department of Neurophysiology and Pathophysiology, University Medical Center Hamburg-Eppendorf, Hamburg 20246, Germany.
J Neurosci. 2015 May 13;35(19):7403-13. doi: 10.1523/JNEUROSCI.5114-14.2015.
The brain is proposed to operate through probabilistic inference, testing and refining predictions about the world. Here, we search for neural activity compatible with the violation of active predictions, learned from the contingencies between actions and the consequent changes in sensory input. We focused on vision, where eye movements produce stimuli shifts that could, in principle, be predicted. We compared, in humans, error signals to saccade-contingent changes of veridical and inferred inputs by contrasting the electroencephalographic activity after saccades to a stimulus presented inside or outside the blind spot. We observed early (<250 ms) and late (>250 ms) error signals after stimulus change, indicating the violation of sensory and associative predictions, respectively. Remarkably, the late response was diminished for blind-spot trials. These results indicate that predictive signals occur across multiple levels of the visual hierarchy, based on generative models that differentiate between signals that originate from the outside world and those that are inferred.
大脑被认为是通过概率推理来运作的,即测试和完善对世界的预测。在此,我们寻找与违反主动预测相兼容的神经活动,这些预测是从动作与感官输入的后续变化之间的偶发事件中学习到的。我们聚焦于视觉,其中眼球运动产生的刺激变化原则上是可以预测的。在人类中,我们通过对比扫视后呈现于盲点内或盲点外的刺激所引发的脑电图活动,将错误信号与真实和推断输入的扫视相关变化进行了比较。我们观察到刺激变化后出现了早期(<250毫秒)和晚期(>250毫秒)错误信号,分别表明违反了感官预测和联想预测。值得注意的是,盲点试验的晚期反应有所减弱。这些结果表明,基于区分源自外部世界的信号和推断信号的生成模型,预测信号出现在视觉层级的多个层面。