Inhibition of return (IOR) is modulated by task set and appears later in discrimination tasks than in detection tasks. Several hypotheses have been suggested to account for this difference. We tested three of these hypotheses in two experiments by examining the influence of cue and target level of processing on the onset of IOR. In the first…

The effects of moving task-irrelevant objects on time-to-contact (TTC) judgments were examined in 5 experiments. Observers viewed a directly approaching target in the presence of a distractor object moving in parallel with the target. In Experiments 1 to 4, observers decided whether the target would have collided with them earlier or later than a…

In cross-dimensional visual search tasks, target discrimination is faster when the previous trial contained a target defined in the same visual dimension as the current trial. The dimension-weighting account (DWA; A. Found & H. J. Muller, 1996) explains this intertrial facilitation by assuming that visual dimensions are weighted at an early…

What happens after visual attention is allocated to an object? Although many theories of attention assume that all of its features are selected and processed, there has been little direct evidence that an irrelevant feature dimension of an attended nontarget is processed. In 5 experiments presented here, the authors used a singleton paradigm to…

The holistic-discriminability model of object-space perception recognizes various classes of stimuli having different task requirements, with few assumptions. The alternative analytic model, contrary to Dykes and Cooper, is inadequate; it involves many assumptions, predicts only a limited set of data and makes some incorrect predictions.…