title: The role of learning-related dopamine signals in addiction vulnerability.
abstract: Dopaminergic signals play a mathematically precise role in reward-related learning, and variations in dopaminergic signaling have been implicated in vulnerability to addiction. Here, we provide a detailed overview of the relationship between theoretical, mathematical, and experimental accounts of phasic dopamine signaling, with implications for the role of learning-related dopamine signaling in addiction and related disorders. We describe the theoretical and behavioral characteristics of model-free learning based on errors in the prediction of reward, including step-by-step explanations of the underlying equations. We then use recent insights from an animal model that highlights individual variation in learning during a Pavlovian conditioning paradigm to describe overlapping aspects of incentive salience attribution and model-free learning. We argue that this provides a computationally coherent account of some features of addiction.
authors: Translational Neuromodeling Unit, Department of Biomedical Engineering, ETH Zürich and University of Zürich, Zürich, Switzerland; Department of Psychiatry, Psychosomatics and Psychotherapy, Hospital of Psychiatry, University of Zürich, Zürich, Switzerland. Electronic address: qhuys@cantab.net.
authors: Quentin J M
authors: QJ
authors: Huys
authors: Department of Economics, Laboratory for Social and Neural Systems Research, University of Zürich, Zürich, Switzerland.
authors: Philippe N
authors: PN
authors: Tobler
authors: Department of Psychiatry, University of Bern, Bern, Switzerland.
authors: Gregor
authors: G
authors: Hasler
authors: Department of Psychiatry, University of Michigan, Ann Arbor, MI, USA; Molecular and Behavioral Neuroscience Institute, University of Michigan, Ann Arbor, MI, USA.
authors: Shelly B
authors: SB
authors: Flagel
mesh_terms: D000818:Animals; D016739:Behavior, Addictive / Q000503:physiopathology; D004298:Dopamine / Q000502:physiology*; D006801:Humans; D007858:Learning / Q000502:physiology*; D008959:Models, Neurological; D012054:Reinforcement, Psychology; D012201:Reward; D015398:Signal Transduction; D019966:Substance-Related Disorders / Q000503:physiopathology*
chemical_list: D004298:Dopamine
keywords: addiction; dopamine; incentive salience; model-free; prediction error; reinforcement learning; sign-tracking