PUB - Publikationen an der Universität Bielefeld

The surprise-attention hypothesis, stating that expectancy-discrepant stimuli can capture attention, is tested in two visual search experiments with accuracy as the dependent variable. The expectancy-discrepant stimulus was the unannounced presentation of a location precue in a new colour. As the precue was presented at the location of a nontarget, attentional capture was expected to register in a performance decrement in the critical trial. Experiment 1 revealed that attentional effects are absent after 100 ms but present after 400 ms. Experiment 2 showed that this effect is due partly to presentation duration. These results indicate that surprise capture has a late onset and requires a stable representation. In addition, the results indicate that traditional measures of attention capture and verbal reports of awareness can dissociate.