A predictive coding account of bistable perception - a model-based fMRI study

PLoS Comput Biol. 2017 May 15;13(5):e1005536. doi: 10.1371/journal.pcbi.1005536. eCollection 2017 May.

Abstract

In bistable vision, subjective perception wavers between two interpretations of a constant ambiguous stimulus. This dissociation between conscious perception and sensory stimulation has motivated various empirical studies on the neural correlates of bistable perception, but the neurocomputational mechanism behind endogenous perceptual transitions has remained elusive. Here, we recurred to a generic Bayesian framework of predictive coding and devised a model that casts endogenous perceptual transitions as a consequence of prediction errors emerging from residual evidence for the suppressed percept. Data simulations revealed close similarities between the model's predictions and key temporal characteristics of perceptual bistability, indicating that the model was able to reproduce bistable perception. Fitting the predictive coding model to behavioural data from an fMRI-experiment on bistable perception, we found a correlation across participants between the model parameter encoding perceptual stabilization and the behaviourally measured frequency of perceptual transitions, corroborating that the model successfully accounted for participants' perception. Formal model comparison with established models of bistable perception based on mutual inhibition and adaptation, noise or a combination of adaptation and noise was used for the validation of the predictive coding model against the established models. Most importantly, model-based analyses of the fMRI data revealed that prediction error time-courses derived from the predictive coding model correlated with neural signal time-courses in bilateral inferior frontal gyri and anterior insulae. Voxel-wise model selection indicated a superiority of the predictive coding model over conventional analysis approaches in explaining neural activity in these frontal areas, suggesting that frontal cortex encodes prediction errors that mediate endogenous perceptual transitions in bistable perception. Taken together, our current work provides a theoretical framework that allows for the analysis of behavioural and neural data using a predictive coding perspective on bistable perception. In this, our approach posits a crucial role of prediction error signalling for the resolution of perceptual ambiguities.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Bayes Theorem
  • Computational Biology
  • Computer Simulation
  • Female
  • Frontal Lobe / physiology
  • Humans
  • Magnetic Resonance Imaging / methods*
  • Male
  • Models, Neurological*
  • Task Performance and Analysis
  • Visual Perception / physiology*
  • Young Adult

Grants and funding

VW is a participant in the Charité Junior Clinical Scientist Program funded by the Charité Universitaetsmedizin Berlin and the Berlin Institute of Health; German Federal Ministry of Education and Research within the framework of the e:Med research and funding concept (01ZX1404A to KS); German Research Foundation (grants HE 6244/1-2 to GH, STE 1430/7-1 to PS); KS is a participant in the Charité Clinical Scientist Program funded by the Charité Universitaetsmedizin Berlin and the Berlin Institute of Health. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.