Abstract
Visual features of an object can be properties of either its surface (such as color or texture) or its boundary (such as shape or size). Previous visual short-term memory studies have focused on the importance of object number in determining capacity limits, but an "object" might have any number of distinct surfaces and boundary contours. In the current study, we explore how the organization of surfaces and boundaries that indicate two task-relevant features can influence memory performance. In Experiment 1, memory for two task-relevant features (color and orientation) was tested in four display conditions utilizing different surface and boundary organizations for the object stimuli. Experiment 2 tested the same four display conditions using two boundary features, size and shape, as the task-relevant features. Both experiments were conducted using both a full probe trial-type, where all studied objects reappeared at test, and a partial probe trial-type, where only one object reappeared at test. The combination of display conditions and probe trial-types allow us to distinguish effects from both local proximity of the features and utilization of the global spatial layout of the display. The results of Experiments 1 and 2 show significant differences depending on display type that interact with probe type. Interestingly, the results suggest the differences between surface and boundary organizations of the stimuli were mediated by differences in the utilization of either local proximity of the features or the global spatial layout of the display. This finding suggests some effects of object status on memory performance observed in previous studies may be mediated by how effectively these proximity cues can be utilized by participants.
Meeting abstract presented at VSS 2017