Contextual modulation of value signals in reward and punishment learning

• Published in: Nature communications Vol. 6; no. 1; p. 8096
• Main Authors: Palminteri, Stefano, Khamassi, Mehdi, Joffily, Mateus, Coricelli, Giorgio
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 25.08.2015; Nature Publishing Group; Nature Pub. Group
• Subjects: 631/378/1457/1369; 631/378/1457/1936; 631/378/1595; 631/378/2629/1788; Adult; Avoidance Learning - physiology; Bayes Theorem; Brain - physiology; Brain Mapping; Cerebral Cortex - physiology; Cognitive Sciences; Computer Simulation; Decision Making - physiology; Economics and Finance; Female; Functional Neuroimaging; Humanities and Social Sciences; Humans; Image Processing, Computer-Assisted; Learning - physiology; Life Sciences; Magnetic Resonance Imaging; Male; Models, Neurological; multidisciplinary; Neurons and Cognition; Prefrontal Cortex - physiology; Punishment; Reward; Science; Science (multidisciplinary); Ventral Striatum - physiology; Young Adult; reward; punishment; learning; neuroscience; biological sciences
• DOI: 10.1038/ncomms9096
• ISSN: 2041-1723

Compared with reward seeking, punishment avoidance learning is less clearly understood at both the computational and neurobiological levels. Here we demonstrate, using computational modelling and fMRI in humans, that learning option values in a relative—context-dependent—scale offers a simple computational solution for avoidance learning. The context (or state) value sets the reference point to which an outcome should be compared before updating the option value. Consequently, in contexts with an overall negative expected value, successful punishment avoidance acquires a positive value, thus reinforcing the response. As revealed by post-learning assessment of options values, contextual influences are enhanced when subjects are informed about the result of the forgone alternative (counterfactual information). This is mirrored at the neural level by a shift in negative outcome encoding from the anterior insula to the ventral striatum, suggesting that value contextualization also limits the need to mobilize an opponent punishment learning system. In contrast to predictions from learning theory, humans learn to seek rewards and avoid punishments equally well. Here the authors offer an elegant solution to this problem by demonstrating that humans learn option values relative to a reference point subserved by a common neural substrate.