Willem-Paul Brinkman, R. Haakma, D.G. Bouwhuis. Memory Load: a Factor that Links the Usability of Individual Interaction Components Together. Preprint 2004.
An underlying assumption of component-based software engineering for interactive systems is that the overall usability of a new assembled system mainly depends on the usability of its individual components. This paper challenges this assumption by presenting findings of a lab experiment. Here users were asked to use two calculators, one with a small display and one with a large display. Results show a significant change in the way users solved equations with the two calculators when faced with high memory demands. Although the effects of memory load is not new, these findings show empirically how it can also affect the interaction with components not directly responsible for it. Therefore when constructing a new system out of ready-made components, developers should still evaluate the new system as a whole since usable components tested in isolation might still have a negative effect on the way users interact with other components.