Funded Grants

Neurobiology of human decision making

Imagine playing a game against a clever human opponent. On each round you must decide whether to play rock, paper or scissors. Rock breaks scissors, scissors cut paper, paper wraps rock. If the two players make identical selections the round repeats. Suppose each of the three definitive outcomes yields a winner who gains a dollar and a loser who forfeits a dollar. In a decision making problem like this, you must learn by experience the strategies that your opponent employs. You must identify the risks associated with playing rock or paper or scissors and then select, on each round, a strategy.

Over the last decade, cognitive neuroscientists have used two different methods to begin to explore the physiological systems that make decisions like these, fMRI and single-unit recording. Both of these techniques provide tools for understanding brain function, but both face limitations. The low temporal and spatial resolution of fMRI largely precludes the examination of quantitative mechanistic hypotheses. And to a single-unit electrode the sheer scale of the brain forces all studies to be about local, rather than global, processes. A very small group of laboratories have addressed these limitations by employing parallel electrophysiological and fMRI experiments. In these laboratories, fMRI provides global perspectives while single unit studies test quantitative hypotheses which emerge from the fMRI data at the cellular computational level. Unfortunately, none of these groups has begun to examine the neural architecture for decisionmaking.

Over the past year a number of factors have led my group to conclude that our effort to understand decision-making has reached a point where a combined fMRI and single-unit approach is now required. Unfortunately, we lack expertise in fMRI. In principle, we could acquire expertise by collaborating with David Heeger's group at Stanford before building a stand-alone fMRI program in our laboratory at NYU. This would require that I, and one post-doc, spend significant time as apprentices with Heeger's group. Over the course of a 3-4 year period we would then gain sufficient expertise to independently undertake fMRI projects at NYU using the new Cognitive Neuroscience Center now under construction. The proposal that follows describes a four year project for studying decision-making using fMRI. The research would yield significant new results, but the real goal of the project would be to develop expertise with fMRI in my laboratory that would be adequate to ensure future government funding of research on these problems.