Brain's voluntary chain-of-command ruled by not one but two captains

A probe of the upper echelons of the human brain's chain-of-command has found strong evidence that there are not one but two complementary commanders in charge of the brain. It's as if Captains James T. Kirk and Jean-Luc Picard were both on the bridge and in command of the same starship Enterprise. In reality, these two captains are networks of brain regions that do not consult each other but still work toward a common purpose -- control of voluntary, goal-oriented behavior. "This was a big surprise. We knew several brain regions contribute to top-down control, but most of us thought we'd eventually show all those regions linking together in one system, one little guy up top telling everyone else what to do."