Change blindness is considered to be caused by failure of the retrieval/comparison process for the changed item. However, it is not clear what information is used in this process. Here, we investigated whether or not information about individual features within object representations retained in visual working memory (VWM) are available through the retrieval/comparison process when the VWM representation of the pre-change scene is compared with sensory input. Observers performed a dual task, which included change detection and rapid serial visual presentation (RSVP) tasks. Regardless of whether change detection and RSVP targets were defined by the same feature or by different features, change detection was impaired under the dual task condition. This suggests that the retrieval/comparison process detects change not by comparing the individual features involved in VWM representation and sensory inputs, but rather by comparing “objects” within which individual features are integrated.
