Friday, May 13, 2005

12 noon

Redwood Neuroscience Institute

 

Title:  “Foraging for cortical reward signals: behavior, modeling, and electrophysiology”

 

Greg Corrado

Neuroscience Department

Stanford University

 

Abstract:

To forage successfully animals must maintain an internal representation of the value or utility of competing options and link that representation to the neural processes responsible for decision- making and action implementation.  In this lecture I will outline a general approach to the electrophysiological study of value-based choice in awake, behaving monkeys.  This approach has three key components: first, demonstrating that behavior is under the control of an animal’s history of choices and rewards; second, modeling behavioral data to gain insight into the decision variables that  specify the animal’s choices; and third, analyzing electrophysiological signals to determine if and how these decision  variables are encoded within specific neural systems.

 

I will discuss how we have applied this approach to study choice behavior and related neural activity in rhesus monkeys engaged in a dynamic foraging game.  This work demonstrates the efficacy of a simple Linear-Nonlinear-Poisson framework in producing successful predictive and generative models of animal foraging behavior that in turn provide useful candidate decision variables for neurophysiological investigation.  To date our physiological experiments have focused on exploring neural signals in each of two areas of cortex that are implicated in reward processing or higher order motor planning.  I will discuss the results of single cell recording experiments conducted in these areas while monkeys engaged 

in this foraging game, and what these results suggest about the respective roles of these areas in value-based decision making.