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)