On the ability to inhibit thought and action: A theory of an act of control.

Many situations require people to stop or change their current thoughts and actions. We present a theory of the inhibition of thought and action to account for people's performance in such situations. The theory proposes that a control signal, such as an external stop signal or an error during performance, starts a stopping process that races against the processes underlying ongoing thought and action. If the stopping process wins, thought and action are inhibited; if the ongoing process wins, thought and action run on to completion. We develop the theory formally to account for many aspects of performance in situations with explicit stop signals, and we apply it to several sets of data. We discuss the relation between response inhibition and other acts of control in motor performance and in cognition, and we consider how our theory relates to current thinking about attentional control and automaticity.