Does Dynamic Visual Noise Eliminate the Concreteness Effect in Working Memory?

Dynamic visual noise (DVN), an array of squares that randomly switch between black and white, interferes with certain tasks that involve visuo-spatial processing. Based on the assumption that the representation of concrete words includes an imagistic code whereas that of abstract words does not, Parker and Dagnall (2009) predicted that DVN should disrupt visual working memory and selectively interfere with memory for concrete words. They observed a reversal of the concreteness effect in both a delayed free recall and a delayed recognition test. In six studies, we partially replicate and extend their work. In Experiments 1 (delayed free recall) and 2 (delayed recognition), DVN abolished, but did not reverse, the concreteness effect. Experiments 3 and 4 found no effect of DVN on a prototypical working memory task, immediate serial recall: concreteness effects were observed in both the control and DVN conditions. In contrast, Experiment 5 showed that DVN abolished the concreteness effect in an immediate serial recognition test. In the final experiment, subjects did not know whether they would receive an immediate serial recall or an immediate serial recognition test until after the list had been presented. Nonetheless, DVN had no effect on immediate serial recall but once again eliminated the concreteness effect on immediate serial recognition. The results (1) extend the effects of DVN on the concreteness effect to working memory tasks, (2) suggest that immediate serial recall and immediate serial recognition are more different than similar, and (3) have implications for theories of DVN, the concreteness effect, and models of memory.