Role of practice and stimulus-onset-asynchrony in modulating effects of stimulus repetition, category relation, and response compatibility in the Eriksen flanker task.

In the Eriksen flanker task, irrelevant information influences reaction time based on three types of relationships between target and flanker, Stimulus Repetition, Category Relation, and Response Compatibility. The effects of Stimulus Repetition and Category Relation refer to the finding that reaction time is faster when the target and flankers are the same or belong to the same category, respectively. The effect of Response Compatibility refers to the finding that reaction time is faster when the target and flankers are assigned to the same response than to different responses. Two experiments were designed to examine whether these effects vary with practice and stimulus-onset-asynchrony. It was shown that the effects of Stimulus Repetition and Category Relation occurred only when the flankers preceded the target by 200 msec. The effect of Response Compatibility, however, occurred regardless of stimulus-onset-asynchrony. Furthermore, limited practice seems necessary for the occurrence of response facilitation.