Auditory and visual capture

It is well known that auditory and visual onsets presented at a particular location can capture our visual attention. However, the question whether or not such attentional capture disappears when attention is focused endogenously beforehand has not yet been answered. Moreover, previous studies have not differentiated between capture by onsets presented at a non-target (invalid) location and possible performance benefits occurring when the target location is (validly) cued. In this study we modulated the degree of attentional focus by presenting endogenous cues with varying reliability and by displaying placeholders indicating the precise areas where the target stimuli could occur. By using not only valid and invalid exogenous cues, but also neutral cues which provide temporal but no spatial information, we found performance benefits as well as costs when attention is not strongly focused. The benefits disappear when the attentional focus is increased. Our results indicate that there is bottom-up capture of visual attention by irrelevant auditory and visual stimuli that can not be suppressed by top-down attentional control.