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NJIT Mathematical Biology Seminar

Tuesday, November 27, 2007, 4:00pm
Cullimore Hall 611
New Jersey Institute of Technology

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Free choice activates a decision circuit between frontal and parietal cortex

Bijan Pesaran

Center for Neural Science, New York University

In daily life, we often face alternatives that we are free to choose between. Selecting and planning movements involves a number of areas in frontal and parietal cortex that are anatomically-connected into long-range circuits. During decision making, these areas need to coordinate their activity to select a common movement goal, which could lead to greater correlations in their neuronal activity. Despite this, how neural circuits recruit individual neurons during decision making remains poorly understood. We have simultaneously recorded from the dorsal premotor area (PMd) in frontal cortex and the parietal reach region (PRR) in parietal cortex to investigate neural circuit mechanisms for decision making. We find that correlations in spike and local field potential (LFP) activity between these areas are greater when monkeys are freely-making choices than when they are following instructions. We find that these spike-field correlations reflect the activity of single neurons and are not explained by correlations between LFP activity recorded in each area. Moreover, neurons participating in the long-range coherent activity encode the chosen location of the movement goal earlier than those that don^Rt. We propose that a decision circuit featuring a sub-population of cells in frontal and parietal cortex exchanges information to coordinate activity between these areas. This decision circuit may influence movement choices by providing a common bias to the selection of movement goals in different areas of the brain.