Abstract
Proactive interference (PI) is when an item previously held in memory interferes with a new memory item. Previous studies investigating PI in WM with real-world objects have shown it to be critically dependent on the method of presentation. When items are presented sequentially, there is a large PI effect (Endress & Potter, 2014). When objects are presented simultaneously at different spatial locations, there is little effect of repeating items trial to trial (Makovski, 2016), suggesting little role for LTM in the standard change detection task, even with real-world objects. We asked whether the distinction between simultaneous and sequential was because location representations were critical to PI. On each trial, participants were shown a 4-object array for 1s. Objects didn't repeat across the experiment. After a brief delay, one of the object's location was cued, followed by a 7AFC task. The choices included the object from the cued location and other two locations of the current trial, objects from the same locations on the previous trial, and an object that didn't appear in the current or previous display. Selection of objects shown in the previous trial is evidence of PI, and selection of the location-matched objects is evidence that location is an important part of this PI. Overall, we found only a small PI effect, consistent with previous literature on simultaneous displays. However, this small PI effect was not dependent on spatial location: participants were as likely to select a foil from the previous trial that did not match the current target location as one that did. The lack of location specificity may indicate that the main distinction between simultaneous and sequential presentation is not location per se. Instead, participants may rely on different strategies when encoding simultaneous displays and sequential displays, relying more on LTM representations in sequential presentation.
Meeting abstract presented at VSS 2018