On the role of working memory in response interference.

A recent study by de Fockert, et al. claimed that working memory and selective attention are interacting cognitive systems. We used a dual task design that closely resembled de Fockert, et al.'s experiment, but using different stimuli. Our subjects first had to store the positions and sequence of a number of blocks. During storage they then had to respond to a few selective attention trials, after which memory was tested. Selective attention was tested using a computerized version of the color Stroop task and the Simon task. We expected to find a monotonic increase of response interference with increasing working memory load, but we found only modest evidence of an influence of working memory on attention. The results shed new light on the nature of and the relation between these cognitive systems.