Cued visual selection of conjunction targets – no evidence of additional attentional requirements for the binding of color and orientation

Abstract

The technique of cued visual selection (CVS) was used to measure dynamic processes in the identification of combined color and orientation targets. It has been proposed that the different features in such items must be attentively linked together for correct identification. In arrays of red and green lines at different orientations, one line (which thus became the target) was cued and had to be identified. Like with onefeature identification tasks in CVS, in which color is generally faster identified than orientation, observers also identified the color of combined targets faster than their orientation. Even in conjunction targets thus, features are identified largely independent from each other. False conjunctions were not obtained from a lack of attention but because one or the other feature was not yet correctly identified. When the performance in (separate) one-feature identification tasks was taken to predict the performance in the (combined) conjunction task, orientation identification was found to be slightly accelerated compared to the predictions. An analogue effect in color was not seen or notably smaller and in the opposite direction. Detailed analysis however showed that the improvement of orientation identification in conjunction tasks was not achieved on the cost of simultaneous color identification, nor was iFigs.t explained by learning effects or possible luminance differences in the tasks. It rather seems to reflect a better encoding of orientation signals in color channels or a better utilization of attentional resources in conjunction than in pure orientation tasks. Altogether there is no evidence that the attentional resources needed for target identification were also used for the binding of target feature components. © Autho