On the costs and benefits of repeating a nonspatial feature in an exogenous spatial cuing paradigm.

Recent research using the Posner cuing paradigm to explore inhibition of return seems to suggest that repetition of a nonspatial feature modulates cue-related facilitatory and inhibitory aftereffects differently in detection and discrimination tasks. Because the cues were unrelated to the final response in the detection task but parallel to (not orthogonal with) the final response in the discrimination task, it is unclear whether the different patterns of results were caused by the complexity of the decision (detection vs. discrimination) or by the task relevance of the feature that might or might not repeat from cue to target. Using a paradigm modeled on previous work, in Experiment 1 (detection task) and 2 (discrimination task) we replicated the previous patterns: No early feature repetition benefit but reduced IOR for feature mismatch trials in the detection task; and large early feature repetition benefit but no effect of feature match upon the later IOR in the discrimination task. In Experiment 3 (discrimination task), we used an "orthogonal-cuing" method: the feature (color) that could repeat or not from cue to target was not on the dimension being discriminated (shape). The pattern of results was very similar to what is observed in detection tasks. These results demonstrate that it is not the task but the task relevance of the repeating feature that modulates facilitation and inhibition effects. The findings are generally consistent with a habituation account of the inhibitory aftereffects of orienting but do not rule out the contribution of other mechanisms.