The binding of features in visual short-term memory

Abstract

Recent studies of visual short-term memory have revealed surprising limitations on the capacity and detail of its object representations. Several studies have demonstrated our ability to integrate features across dimensions in memory tasks, but few have examined whether or not task-irrelevant features from different dimensions may interfere in memory. We used a change-detection paradigm to investigate the binding and potential interference between features and locations of an array of boxes in a 3-dimensional virtual environment. Participants were asked to judge whether or not one of the boxes had moved between study and test and to ignore the patterns on the boxes. The boxes retained the same pattern on half of the trials; on the other half, all the patterns were replaced with new ones. Participants were more likely to judge that a box had moved when the patterns were changed than when they were not. Thus, even though features from different dimensions may be integrated efficiently in memory, this integration may result in degraded performance on tasks that require the retrieval of only one feature dimension. These results then imply a restriction on the information retained when selective recall of a particular feature is required. Further studies will investigate the nature and strength of this effect.