Gain and Loss in Optimistic Versus Pessimistic Brains

PASADENA, Calif.—Our belief as to whether we will likely succeed or fail at a given task—and the consequences of winning or losing—directly affects the levels of neural effort put forth in movement-planning circuits in the human cortex, according to a new brain-imaging study by neuroscientists at the California Institute of Technology (Caltech). A paper about the research—led by Richard A. Andersen, the James G. Boswell Professor of Neuroscience at Caltech—appears in the August issue of PLoS Biology . Research in Andersen's laboratory includes work to understand the neural mechanisms of action planning and decision-making. The lab is working toward the development of implanted neural prosthetic devices that would serve as an interface between severely paralyzed individuals' brain signals and artificial limbs—allowing their planned actions to control the limbs' movements. In particular, Andersen's group focuses on a high-level area of the brain called the posterior parietal cortex (PPC), where sensory stimuli are transformed into movement plans. In the current study, Andersen and his colleagues used a functional magnetic resonance imaging scanner to monitor activity in the PPC and other brain areas in subjects who were asked to perform a complex task. Using a trackball, they had to move a cursor to a number of memorized locations on a computer screen, in a predetermined order.