Does feature similarity facilitate attentional selection?

Abstract

Object-based attention enables us to simultaneously select and report two features from the same visual object. Does feature-based attention contribute similarly to visual selection? In the present study, we investigated the concurrent discrimination of two motion fields with a divided attention paradigm. We found that dual-task performance improved when the two fields conformed to a continuous optic flow, consistent with "object-based" selection. However, we found no such improvement when the two motion fields were merely similar, as would have been expected from "feature-based" selection. Therefore, feature similarity does not facilitate attentional selection in the same way as belonging to the same object does.