ABSTRACT
One of the more important facts about compatibility effects is that they occur for stimulus dimensions that are irrelevant to the task at hand. That is, even though a dimension along which stimuli vary may be defined as irrelevant, responses are often faster and more accurate when the value of that stimulus dimension corresponds with the response signaled by the relevant stimulus dimension than when it does not. As with S-R compatibility proper, correspondence effects for an irrelevant stimulus dimension with a response dimension have been studied most extensively using spatial location, in which case responses are faster when the irrelevant stimulus location corresponds with the location of the response that is to be made. The
Simon effect
, introduced in Chapter 1, is the name given to this advantage in response selection for corresponding S-R locations for tasks in which the stimulus location is irrelevant and the relevant dimension (e.g., color) is not spatial in nature. The Simon effect has received increasing emphasis in recent years in studies of perceptionaction relations, as indicated by the fact that entering “Simon Effect” as a keyword into the PsycINFO index in the first week of January 2006, yielded 151 entries, 87 of which were published in the year 2000 or later. Correspondence effects of this type for other dimensions such as stimulus and response duration are often called Simon-type effects.
