This chapter presents a theory of prefrontal cortex function using the connectionist computational modeling framework. This modeling approach involves three components: computational analysis of the critical processing mechanisms required for cognitive control; use of neurobiologically plausible principles of information processing; and implementation and simulation of cognitive tasks and behavioral performance. The chapter describes behavioral and neuroimaging data on healthy young adults that validate critical components of the model. It then summarizes the application of the model to the clinical domain. These (...) studies highlight the power of the cognitive neuroscience approach by demonstrating how a single, integrated account of PFC function can capture a wide range of data from different methodologies and multiple populations. (shrink)

The prefrontal cortex has long been suspected to play an important role in cognitive control, in the ability to orchestrate thought and action in accordance with internal goals. Its neural basis, however, has remained a mystery. Here, we propose that cognitive control stems from the active maintenance of patterns of activity in the prefrontal cortex that represent goals and the means to achieve them. They provide bias signals to other brain structures whose net effect is to guide the flow of (...) activity along neural pathways that establish the proper mappings between inputs, internal states, and outputs needed to perform a given task. We review neurophysiological, neurobiological, neuroimaging, and computational studies that support this theory and discuss its implications as well as further issues to be addressed. (shrink)