Columbia University in the City of New York

Oct 26, 20211:00 pm
Seminar

The brain is a mixture of experts: how the brain allocates control as a function of the reliability of predictions.

Featuring John P. O’Doherty, PhD, Professor of Psychology, California Institute of Technology

October 26th, 1:00 pm – 2:00 pm

Click here to register

 

It has long been suggested that human behavior can be understood as reflecting the contributions of multiple systems that cooperate or compete for the control of behavior. Here we suggest that the brain can be thought of as a “Mixture of Experts” in which multiple different expert systems propose strategies for action. Here I will consider how the brain determines which system should control behavior at any one moment in time. It will be argued that this is accomplished by keeping track of the reliability of the predictions within each system, and by allocating control over behavior in a manner that is proportional to the relative reliability of those predictions. I will present behavioral evidence for the existence of a reliability-based control mechanism operating over multiple experts in humans. These include model-based and model-free reinforcement-learning strategies that learn to select actions on the basis of direct experience, experts that learn to select actions through observing the behavior of other agents, as well as a system that reflexively takes actions based solely on visual affordances. I will then present some neuroimaging and neurostimulation data that suggest a specific contribution of the ventrolateral prefrontal cortex in this reliability-based arbitration process. Results from the study of different expert systems in both experiential and social-learning domains hint at the possibility that this reliability-based control mechanism is domain-general, exerting control over many different expert systems simultaneously in order to yield sophisticated behavior.      

Those wishing to meet the speaker should contact Nicholas Singletary and Justin Buck in the Horga Lab.   


The Columbia Neuroscience Seminar series is a collaborative effort of Columbia's Zuckerman Institute, the Department of Neuroscience, the Doctoral Program in Neurobiology and Behavior and the Columbia Translational Neuroscience Initiative, and with support from the Kavli Institute for Brain Science.

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