Yarkoni, T., Braver, T. S., Gray, J. R., & Green, L. (2005).
Prefrontal brain activity predicts temporally extended decision-making behavior.
Journal of the Experimental Analysis of Behavior, 84, 537-
554.
Although functional neuroimaging studies of human decision-making processes are
increasingly common, most of the research in this area has relied on passive
tasks that generate little individual variability. Relatively little attention
has been paid to the ability of brain activity to predict overt behavior. Using
functional magnetic resonance imaging (fMRI), we investigated the neural
mechanisms underlying behavior during a dynamic decision task that required
subjects to select smaller, short-term monetary payoffs in order to receive
larger, long-term gains. The number of trials over which the long-term gains
accrued was manipulated experimentally (2 versus 12). Event-related neural
activity in right lateral prefrontal cortex, a region associated with high-level
cognitive processing, selectively predicted choice behavior in both conditions,
whereas insular cortex responded to fluctuations in amount of reward but did not
predict choice behavior. These results demonstrate the utility of a functional
neuroimaging approach in behavioral psychology, showing that (a) highly
circumscribed brain regions are capable of predicting complex choice behavior,
and (b) fMRI has the ability to dissociate the contributions of different neural
mechanisms to particular behavioral tasks.
Key words: brain–behavior, decision making, functional magnetic resonance
imaging, maximizing, temporal integration, choice, humans