The nationality benefit: Long-term memory associations enhance visual working memory for color-shape conjunctions

Visual working memory (VWM) is typically found to be severely limited in capacity, but this limitation may be ameliorated by providing familiar objects that are associated with knowledge stored in long-term memory. However, comparing meaningful and meaningless stimuli usually entails a confound, because different types of objects also tend to vary in terms of their inherent perceptual complexity. The current study therefore aimed to dissociate stimulus complexity from object meaning in VWM. To this end, identical stimuli - namely, simple color-shape conjunctions - were presented, which either resembled meaningful configurations (real European flags), or which were rearranged to form perceptually identical but meaningless (fake) flags. The results revealed complexity estimates for real and fake flags to be higher than for unicolor baseline stimuli. However, VWM capacity for real flags was comparable to the unicolor baseline stimuli (and substantially higher than for fake flags). This shows that relatively complex, yet meaningful real flags reveal a VWM capacity that is comparable to rather simple, unicolored memory items. Moreover, this nationality benefit was related to individual flag recognition performance, thus showing that VWM depends on object knowledge.

Automated summary

The current study aimed to dissociate stimulus complexity from object meaning in VWM by presenting identical stimuli that either resembled meaningful configurations (real European flags) or rearranged to form perceptually identical but meaningless (fake) flags. The results showed that VWM capacity for real flags was comparable to unicolor baseline stimuli (and higher than for fake flags), demonstrating that relatively complex, yet meaningful objects reveal a VWM capacity comparable to simple, unicolored memory items. Additionally, the nationality benefit was related to individual flag recognition performance, illustrating the importance of object knowledge in VWM.