In three experiments, participants were presented with a multicolumn subtraction task, which required working memory in half of the trials.
Menno Nijboer, Niels A. Taatgen, Annelies Brands, Jelmer P. Borst, Hedderik van Rijn 2013, 'Decision Making in Concurrent Multitasking: Do People Adapt to Task Interference?',PLoS ONE10.1371/journal.pone.0079583. Retrieved from PLOS CC BY 4.0 (https://creativecommons.org/licenses/by-sa/4.0/legalcode)