Data from: Prediction error and repetition suppression have distinct effects on neural representations of visual information

Predictive coding theories argue that recent experience establishes
expectations in the brain that generate prediction errors when violated.
Prediction errors provide a possible explanation for repetition
suppression, where evoked neural activity is attenuated across repeated
presentations of the same stimulus. The predictive coding account argues
repetition suppression arises because repeated stimuli are expected,
whereas non-repeated stimuli are unexpected and thus elicit larger neural
responses. Here we employed electroencephalography in humans to test the
predictive coding account of repetition suppression by presenting
sequences of visual gratings with orientations that were expected either
to repeat or change in separate blocks of trials. We applied multivariate
forward modelling to determine how orientation selectivity was affected by
repetition and prediction. Unexpected stimuli were associated with
significantly enhanced orientation selectivity, whereas selectivity was
unaffected for repeated stimuli. Our results suggest that repetition
suppression and expectation have separable effects on neural
representations of visual feature information.

预测编码理论认为，近期经验会在大脑中建立预期，当预期被违背时则产生预测误差。预测误差为重复抑制提供了一种可能的解释——相同刺激重复呈现时，诱发的神经活动会减弱。预测编码的解释指出，重复抑制的产生是因为重复刺激是可预期的，而非重复刺激是意外的，因此会引发更大的神经反应。本研究采用人类脑电图（electroencephalography）技术，通过呈现视觉光栅序列来验证重复抑制的预测编码解释：在不同试验块中，光栅的方向被设置为预期重复或预期变化。我们应用多变量前向建模，以确定方向选择性如何受重复和预测的影响。结果显示，意外刺激与显著增强的方向选择性相关，而重复刺激对选择性无影响。这些结果表明，重复抑制与预期对视觉特征信息的神经表征具有可分离的效应。