The presence of a nonresponding effector increases inhibition of return

Inhibition of return (IOR) refers to the performance disadvantage for targe ts presented at an exogenously cued location, relative to an uncued locatio n, at relatively long cue-target onset asynchronies. In this experiment, we investigated the influence on IOR of a nonresponding effector (i.e., the i ndex finger of the nonresponding hand) placed on a response key in a simple -RT task. With peripheral cues and targets, IOR and spatial stimulus-respon se compatibility effects were larger when the nonresponding hand was placed on a response key. IOR-the slowed responding to go signals at the cued loc ation-was accompanied by a lower false alarm rate when no-go signals were p resented there. These findings provide direct evidence for a motoric compon ent to IOR wherein some portion of the inhibition is observed as a criterio n shift against responding to the cued location.