Disruption of Dorsolateral Prefrontal Cortex Decreases Model-Based in Favor of Model-free Control in Humans

• Published in: Neuron (Cambridge, Mass.) Vol. 80; no. 4; pp. 914 - 919
• Main Authors: Smittenaar, Peter, FitzGerald, Thomas H.B., Romei, Vincenzo, Wright, Nicholas D., Dolan, Raymond J.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 20.11.2013; Elsevier Limited; Cell Press
• Subjects: Adolescent; Adult; Behavior; Behavior - physiology; Choice Behavior; Decision making; Female; Functional Laterality - physiology; Humans; Logistics; Male; Memory, Short-Term - physiology; Models, Neurological; Prefrontal Cortex - physiology; Psychomotor Performance - physiology; Theta Rhythm - physiology; Transcranial Magnetic Stimulation; Young Adult
• ISSN: 0896-6273; 1097-4199; 1097-4199
• DOI: 10.1016/j.neuron.2013.08.009

Human choice behavior often reflects a competition between inflexible computationally efficient control on the one hand and a slower more flexible system of control on the other. This distinction is well captured by model-free and model-based reinforcement learning algorithms. Here, studying human subjects, we show it is possible to shift the balance of control between these systems by disruption of right dorsolateral prefrontal cortex, such that participants manifest a dominance of the less optimal model-free control. In contrast, disruption of left dorsolateral prefrontal cortex impaired model-based performance only in those participants with low working memory capacity. •Disrupting right dorsolateral prefrontal cortex impairs flexible model-based choice•This drives behavior toward simpler, model-free control•Results provide causal evidence for neural underpinnings of flexible choice Choices are governed by computationally simple as well as complex systems that compete with each other. In this Report, Smittenaar et al. present causal evidence that the dorsolateral prefrontal cortex is required for such complex, goal-directed decision making.