Stimulus context and reward contingency induce behavioral adaptation in a rodent tactile detection task

• Type of Material: Article
• Authors: Christian Waiblinger, Georgia Institute of Technology; Caroline M. Wu, Georgia Institute of Technology; Michael F. Bolus, Georgia Institute of Technology; Peter Y. Borden, Georgia Institute of Technology; Garrett Stanley, Emory University
• Language: English
• Date: 2019-02-06
• Publisher: Lippincott, Williams & Wilkins
• Publication Version: Final Published Version
• Copyright Statement: © 2019 the authors.
• Final Published Version (URL): http://dx.doi.org/10.1523/JNEUROSCI.2032-18.2018
• Title of Journal or Parent Work: Journal of Neuroscience Nursing
• ISSN: 0888-0395
• Volume: 39
• Issue: 6
• Start Page: 1088
• End Page: 1099
• Grant/Funding Information: P.Y.B. was supported by an NIH National Research Service Award (Predoctoral Fellowship F31NS09869).; M.F.B. was supported by the National Science Foundation (Graduate Research Fellowship Grant DGE-1650044).; C.M.W. was supported by an Undergraduate Research Scholarship from the Georgia Tech Petit Institute.; C.W. was supported by a fellowship from the Deutsche Forschungsgemeinschaft (GZ: WA 3862/1-1); and the National Institutes of Health (Grant U01NS094302).; G.B.S. was supported by the NIH (Grant R01NS085447; and Brain Grants R01NS104928 and U01NS094302).
• Keywords: behavior; rodent; decision making; adaptive; psychophysics; whisker
• Research Categories: Engineering, Biomedical

Abstract

Behavioral adaptation is a prerequisite for survival in a constantly changing sensory environment, but the underlying strategies and relevant variables driving adaptive behavior are not well understood. Many learning models and neural theories consider probabilistic computations as an efficient way to solve a variety of tasks, especially if uncertainty is involved. Although this suggests a possible role for probabilistic inference and expectation in adaptive behaviors, there is little if any evidence of this relationship experimentally. Here, we investigated adaptive behavior in the rat model by using a well controlled behavioral paradigm within a psychophysical framework to predict and quantify changes in performance of animals trained on a simple whisker-based detection task. The sensory environment of the task was changed by transforming the probabilistic distribution of whisker deflection amplitudes systematically while measuring the animal’s detection performance and correspond-ing rate of accumulated reward. We show that the psychometric function deviates significantly and reversibly depending on the probabilistic distribution of stimuli. This change in performance relates to accumulating a constant reward count across trials, yet it is exempt from changes in reward volume. Our simple model of reward accumulation captures the observed change in psychometric sensitivity and predicts a strategy seeking to maintain reward expectation across trials in the face of the changing stimulus distribution. We conclude that rats are able maintain a constant payoff under changing sensory conditions by flexibly adjusting their behavioral strategy. Our findings suggest the existence of an internal probabilistic model that facilitates behavioral adaptation when sensory demands change.