Prediction Error and Repetition Suppression Have Distinct Effects on Neural Representations of Visual Information

Predictive coding theories argue recent experience establishes expectations in the brain that generate prediction errors when violated. Prediction errors provide a possible explanation for repetition suppression, in which evoked neural activity is attenuated across repeated presentations of the same stimulus. According to the predictive coding account, repetition suppression arises because repeated stimuli are expected, 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 gratings with orientations that were expected to repeat or change in separate blocks. 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 there was no such influence on selectivity for repeated stimuli. Our results suggest that repetition suppression and expectation have separable effects on neural representations of visual feature information.