Abstract

Generative models, such as predictive coding, posit that perception results from a combination of sensory input and prior prediction, each weighted by its precision (inverse variance), with incongruence between these termed prediction error (deviation from prediction) or surprise (negative log probability of the sensory input). However, direct evidence for such a system, and the physiological basis of its computations, is lacking. Using an auditory stimulus whose pitch value changed according to specific rules, we controlled and separated the three key computational variables underlying perception, and discovered, using direct recordings from human auditory cortex, that surprise due to prediction violations is encoded by local field potential oscillations in the gamma band (>30 Hz), changes to predictions in the beta band (12-30 Hz), and that the precision of predictions appears to quantitatively relate to alpha band oscillations (8-12 Hz). These results confirm oscillatory codes for critical aspects of generative models of perception.

Article and author information

Author details

  1. William Sedley

    Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom
    For correspondence
    willsedley@gmail.com
    Competing interests
    The authors declare that no competing interests exist.
  2. Phillip E Gander

    Human Brain Research Laboratory, University of Iowa, Iowa City, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Sukhbinder Kumar

    Institute of Neuroscience, Newcastle University, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  4. Christopher K Kovach

    Human Brain Research Laboratory, University of Iowa, Iowa City, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Hiroyuki Oya

    Human Brain Research Laboratory, University of Iowa, Iowa City, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Hiroto Kawasaki

    Human Brain Research Laboratory, University of Iowa, Iowa City, United States
    Competing interests
    The authors declare that no competing interests exist.
  7. Matthew A Howard

    Human Brain Research Laboratory, University of Iowa, Iowa City, United States
    Competing interests
    The authors declare that no competing interests exist.
  8. Timothy D Griffiths

    Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.

Ethics

Human subjects: The study was approved by the University of Iowa Institutional Review Board, and with full informed written consent from all participants.

Copyright

© 2016, Sedley 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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  1. William Sedley
  2. Phillip E Gander
  3. Sukhbinder Kumar
  4. Christopher K Kovach
  5. Hiroyuki Oya
  6. Hiroto Kawasaki
  7. Matthew A Howard
  8. Timothy D Griffiths
(2016)
Neural Signatures of Perceptual Inference
eLife 5:e11476.
https://doi.org/10.7554/eLife.11476

Share this article

https://doi.org/10.7554/eLife.11476

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