Abstract
The current study tested the manipulation aspect of encoded items in VWM by indicating possible target items using multiple cues (i.e., retro-cues) after encoding. We hypothesized that the retro-cues would cause the cued items to compete for resources in order for successful maintenances of those items. Specifically, we expected that this competition would decrease the precision of memory representation. In Experiment 1, three arrows were presented as to-be-encoded items, and then a ring-shaped retro-cue(s) indicating one or two encoded location(s) were shown in a retention period. The same-shaped report cue was shown in one of the three locations of the encoded items and prompted participant to recall the orientation of the arrow in the cued location. Results showed that the precision of the reported orientation was lower when two items were cued than when one item was cued, suggesting that there was a competition among the items encoded in VWM. Experiment 2 manipulated the degree of competition by varying the encoding strength of memory items. Specifically, the appearance of two memory items (early-onset items) was followed by that of one item (late-onset item), with all the items simultaneously disappearing later. After the encoding, two items (two early-onset items or early- and late-onset items) were always cued with the equal probability. The same report cue was used to prompt participant to recall the orientation of the arrow. We found that the precision of the reported orientation was lower when the two early-onset items were cued than when the early- and late-onset items were cued, suggesting that the precision of memory representation differs depending on the memory strength of competitors. Taken together, our results suggest that items in VWM compete against each other for access to resources, which was reflected in the precision of memory representation.
Meeting abstract presented at VSS 2016