Inhibition of return to color: A replication and nonextension of Law, Pratt, and Abrams (1995)

We presented subjects with an unpredictive cue that was followed after a 150- to 900-msec interstimulus interval (ISI) by a detection target Cue and target were blue or red squares that appeared at fixation and in an otherwise uniform black field. In a filler condition, a task-irrelevant filler stimulus (magenta square) was presented during the ISI; in a no-filler condition, no stimulus appeared during the IST. Using only a 900-msec IST, Law, Pratt and Abrams (1995) reported slower reaction times (RTs) when cue and target were the same color, but only when the task-irrelevant filler was presented during the ISI. They argued that attention is first drawn to the cue color and that inhibition of return (IOR; see Posner & Cohen, 1984) is established when attention is drawn away from that cue color representation by the task-irrelevant filler Critical to their view is the assumption that IOR occurs only after attention is drawn away from the cue color by the filler. Assuming a time course for the withdrawal of attention from the cue color representation, Law et al.'s view predicts growth of the inhibitory effect as a function of ISI in the filler condition as well as facilitation at early ISIs in the no-filler condition (because there is no filler to withdraw attention fr om the cue color). Contrary to these predictions, we found that the inhibitory effect observed by Law et al. at the 900-msec ISI was present at-and did not vary in magnitude across-the range of ISIs tested. And there was never facilitation in the no filler condition. These results challenge Law et al.'s inference that IOR for foveally presented colors was operating in their paradigm.