| Classic Flanker tasks are widely used in selective attention studies to study under what circumstances task-irrelevant flankers may be processed.Classic Flanker tasks based on the flanker-target congruency manipulation,usually contain three flanker conditions: congruent flankers(target identity),incongruent flankers(the alternative identity for the target),and neutral flankers(other letters).The difference of the response times between the incongruent conditions and the other conditions is used to evaluate the flanker processing.An implicit assumption underlying the congruency manipulation is that the flankers in three conditions(congruent,incongruent,and neutral)attract attention homogeneously,which is consistent with the prediction of the perceptual load theory and the dilution theory.However,in the present study,we found that this assumption might be wrong.A new flanker paradigm that does not rely on the congruency manipulation was used.Experiment 1&2 discovered that incongruent/congruent flankers(more consistent with the target template)attracted more attention than the neutral flanker did.Experiment 3 further showed that the inhomogeneous attractiveness of three types of flankers cannot solely be explained by the stimulus-stimulus congruence effect.The results suggested that the flanker-target similarity might affect the allocation of attention in classic flanker tasks.So that classic flanker tasks are biased measures of selective attention.We suggest that future studies should use a neutral flanker that does not share the potential identities of the target to examine flanker processing. |
