Saeideh Saffar Tabbassi¹ (), Mary Catington¹, Michael Pratte¹; ¹Mississippi State University

Visual perception requires that multiple visual features be perceived and bound together into coherent objects. This consolidation of visual information occurs over a brief period of time, but it is unknown whether features are bound together during consolidation or if they are first consolidated and then bound. For example, we show that color is consolidated within 100 ms whereas shape requires at least 300 ms, and the critical question is what happens when the consolidation of a colored shape is interrupted by a pattern mask at 200 ms. If binding is integral to consolidation, the entire object should be masked. Alternatively, if binding occurs only after feature consolidation, then the mask should interrupt shape processing while the object's color will still be perceived. To investigate binding when a mask interrupts the consolidation of some features of an object but not others, six colored shapes were presented briefly, and participants simultaneously reported both the color and shape of a cued and masked item. The consolidation time for the target item was manipulated, using stimulus-mask onset asynchronies ranging from 100 to 700 ms. The extent of binding at each consolidation time was measured using standard analyses of the joint distribution of color and shape errors. At longer consolidation times, the results replicate previous observations that the color of an object is sometimes reported accurately despite having no knowledge of the object's shape. Critically, when consolidation time was around 200 ms, the rate of these color-without-shape recalls increased, suggesting that the mask interrupted shape processing but spared color. This result shows that feature binding can be broken by interrupting the consolidation of some object features but not others, implying that binding occurs after the consolidation of features.

Acknowledgements: This work was supported by National Institutes of Health Grant R15MH113075