Experimental Psychology has traditionally been partitioned into separate subdisciplines, with surprisingly little communication across the boundaries. Cognition has traditionally occupied one subdiscipline with perception and action occupying another subdiscipline. As a result, theories of cognition have typically neglected the perception and action side of our everyday experience. However, it is possible-even likely-that cognition is constrained by human perceptual-motor capabilities. Furthermore, it is likely that perception and action are constrained by cognition. If such constraints exist, then by ignoring them, cognition researchers have been negligent in their pursuit of a complete picture of human cognition.
The goal of this chapter is to pave the way for investigations into a more complete theory of cognition that pays more than marginal attention to perception and action. This theory is called ACT-R/PM (for ACT-R Perceptual Motor) and consists of a set of modules for perception and action which are integrated with the cognitive facilities of ACT-R. We believe this theory is the most complete theory of cognition, perception, and action to date. We demonstrate some of the potential of this new architecture by modeling a task with both perceptual-motor and cognitive demands.