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.
The EEG data have been deposited on Dryad 10.5061/dryad.3d7kq
Data from: Prediction Error and Repetition Suppression Have Distinct Effects on Neural Representations of Visual InformationDryad Digital Repository, doi:10.5061/dryad.3d7kq.
- Ehsan Arabzadeh
- Jason B Mattingley
- Ehsan Arabzadeh
- Jason B Mattingley
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Human subjects: Each participant provided written informed consent prior to participation. The study was approved by The University of Queensland Human Research Ethics Committee (approval number 2012000392) and was in accordance with the Declaration of Helsinki
- Christopher Summerfield, University of Oxford, United Kingdom
© 2018, Tang et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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