Before a saccade, attention shifts covertly to the saccade target object, allowing the consolidation of target features into VWM and the retention of those features across the saccade. Such transsaccadic memory is critical for establishing object correspondence and perceptual continuity across eye movements. In the present study, we contrasted two hypotheses regarding feature encoding and retention in transsaccadic VWM. First, encoding into VWM might be limited to the features of an object that led to its selection as the saccade target. For example, when searching for a round object, the relevant property for saccade target selection (shape) might be preferentially encoded and retained in transsaccadic VWM. Second, encoding into VWM might be object-based in the sense that all features the target are retained across the saccade, including features that were irrelevant to its selection. In the present study, observers searched for a shape singleton (disk) among distractors (squares) in a circular array. Each shape had a particular color that was incidental to the search task. Participants executed a saccade to the disk, and during the saccade, the array rotated so that the eyes landed between the target disk and an adjacent distractor square. Participants were instructed to correct gaze to the target disk. On key trials, the target and distractor swapped colors during the initial saccade. This change in the color of the target caused significant interference with gaze correction, despite the fact that color was incidental to the task. Similar results were obtained even when participants were given strong incentive to avoid encoding the target color. Thus, participants appear to have minimal control over the object features encoded into transsaccadic VWM. All features of the saccade target, including task-irrelevant features, are encoded, maintained across the eye movement, and consulted when the visual system locates the target after the saccade.
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