No evidence for binding of items to task-irrelevant backgrounds in visual working memory

When representing visual features such as color and shape in visual working memory (VWM), participants also represent the locations of those features as a spatial configuration of location of those features in the display. In everyday life, we encounter objects against some background, yet it is unclear whether the configural representation in memory obligatorily constitutes the entire display, including that (often task-irrelevant) background information. In three experiments, participants completed a change detection task on color and shape; the memoranda were presented either in front of uniform grey backgrounds, a textured background (Experiment 1), or a background containing location place-holders (Experiments 2 and 3). When whole-display probes were presented, changes to the objects locations or feature bindings impacted memory performance – implying that the spatial configuration of the probes influenced their change decision. Furthermore, when only a single item was probed, the effect of changing its location or feature bindings were either diminished or completely extinguished, implying single probes do not necessarily rely on the spatial configuration. Critically, when task-irrelevant backgrounds were also presented, which may have provided a spatial configuration for the single probes, the effect of location or bindings was not moderated. These findings suggest that although the spatial configuration of a display guides VWM-based recognition, this information does not necessarily always influence the decision process during change detection.