Executive Control of Thought and Action *

In addition to processing information about stimuli in the environment, the cognitive system performs executive functions to control and coordinate the processes that deal with environmental stimuli. Several executive functions may be distinguished: (1) Making choices about alternative strategies for processing environmental stimuli; (2) constructing or instantiating a version of the chosen strategy to enable performance on the task; (3) controlling and coordinating execution of the strategy during real-time performance on the task; and (4) disabling or disengaging the strategy in response to changes in goals or changes in the task environment that make the current strategy inappropriate. This paper presents a selective review of research addressing each of these executive functions, focusing on the time and resources used to accomplish each one.