title: Electrophysiological correlates reflect the integration of model-based and model-free decision information.
abstract: In this study, we investigated the interplay of habitual (model-free) and goal-directed (model-based) decision processes by using a two-stage Markov decision task in combination with event-related potentials (ERPs) and computational modeling. To manipulate the demands on model-based decision making, we applied two experimental conditions with different probabilities of transitioning from the first to the second stage of the task. As we expected, when the stage transitions were more predictable, participants showed greater model-based (planning) behavior. Consistent with this result, we found that stimulus-evoked parietal (P300) activity at the second stage of the task increased with the predictability of the state transitions. However, the parietal activity also reflected model-free information about the expected values of the stimuli, indicating that at this stage of the task both types of information are integrated to guide decision making. Outcome-related ERP components only reflected reward-related processes: Specifically, a medial prefrontal ERP component (the feedback-related negativity) was sensitive to negative outcomes, whereas a component that is elicited by reward (the feedback-related positivity) increased as a function of positive prediction errors. Taken together, our data indicate that stimulus-locked parietal activity reflects the integration of model-based and model-free information during decision making, whereas feedback-related medial prefrontal signals primarily reflect reward-related decision processes.
authors.affiliation: Chair of Lifespan Developmental Neuroscience, Department of Psychology, TU Dresden, Dresden, Germany. ben.eppinger@concordia.ca.|Department of Psychology, Concordia University, Loyola Campus, 7141 Sherbrooke Street W., Montreal, Quebec, Canada. ben.eppinger@concordia.ca.
authors.forename: Ben
authors.initials: B
authors.lastname: Eppinger
authors.affiliation: Institute for Customer Insight, University of St. Gallen, St. Gallen, Switzerland.
authors.forename: Maik
authors.initials: M
authors.lastname: Walter
authors.affiliation: Chair of Lifespan Developmental Neuroscience, Department of Psychology, TU Dresden, Dresden, Germany.|Center of Lifespan Psychology, Max Planck Institute for Human Development, Berlin, Germany.
authors.forename: Shu-Chen
authors.initials: SC
authors.lastname: Li
mesh_terms: D000465:Algorithms; D001921:Brain / Q000502:physiology*; D003198:Computer Simulation; D003657:Decision Making / Q000502:physiology*; D004569:Electroencephalography; D005071:Evoked Potentials; D056344:Executive Function / Q000502:physiology; D005246:Feedback; D005260:Female; D006040:Goals; D006184:Habits; D006801:Humans; D008297:Male; D008390:Markov Chains; D008959:Models, Neurological; D009483:Neuropsychological Tests; D012201:Reward; D014796:Visual Perception / Q000502:physiology; D055815:Young Adult
keywords: Decision making; EEG; Model-based; Model-free; Reinforcement learning