Annual Review of Vision Science Coding Principles in Adaptation Alison I. Weber, 1,∗ Kamesh Krishnamurthy, 2,∗ and Adrienne L. Fairhall 1,3 1 Department of Physiology and Biophysics and Computational Neuroscience Center, University of Washington, Seattle, Washington 98195, USA; email: aiweber@uw.edu, fairhall@uw.edu 2 Neuroscience Institute and Center for Physics of Biological Function, Department of Physics, Princeton University, Princeton, New Jersey 08544, USA; email: kameshk@princeton.edu 3 UW Institute for Neuroengineering, University of Washington, Seattle, Washington 98195, USA Annu. Rev. Vis. Sci. 2019. 5:427–49 First published as a Review in Advance on July 5, 2019 The Annual Review of Vision Science is online at vision.annualreviews.org https://doi.org/10.1146/annurev-vision-091718- 014818 Copyright © 2019 by Annual Reviews. All rights reserved ∗ These authors contributed equally to this article Keywords neural coding, efficient coding, redundancy reduction, predictive coding, surprise, inference Abstract Adaptation is a common principle that recurs throughout the nervous sys- tem at all stages of processing. This principle manifests in a variety of phe- nomena, from spike frequency adaptation, to apparent changes in receptive fields with changes in stimulus statistics, to enhanced responses to unex- pected stimuli. The ubiquity of adaptation leads naturally to the question: What purpose do these different types of adaptation serve? A diverse set of theories, often highly overlapping, has been proposed to explain the func- tional role of adaptive phenomena. In this review, we discuss several of these theoretical frameworks, highlighting relationships among them and clarify- ing distinctions. We summarize observations of the varied manifestations of adaptation, particularly as they relate to these theoretical frameworks, fo- cusing throughout on the visual system and making connections to other sensory systems. 427 Annu. Rev. Vis. Sci. 2019.5:427-449. Downloaded from www.annualreviews.org Access provided by University of Washington on 09/27/19. For personal use only.