Tuesday, June 10, 2008
The neural circuits of free choice
We often face alternatives that we are free to choose between. Planning movements to select an alternative involves several areas in frontal and parietal cortex. Pesaran et al. have looked at activity of single brain neurons in these areas when monkeys are free to choose which movement among several alternatives to make versus when they are following instructions. Correlations between simultaneously recorded spikes and local field potentials in dorsal premotor and parietal reach regions (which are anatomically connected into long-range circuits) increase during the free choice condition. They propose that a decision circuit featuring a sub-population of cells in frontal and parietal cortex may exchange information to coordinate activity between these areas, with cells participating in this decision circuit influencing movement choices by providing a common bias to the selection of movement goals.