Heart period variability as mental effort monitor in Human Computer Interaction

Elementary steps of H uman Computer Interaction (HCI), like users' mental actions followed by a series of keystrokes and mouse-clicks, are the basic components of using information technological systems. This is why examination methods capable of assessing users' actual mental effort corresponding to these elementary steps during HCI in a scientifically sound way have great importance. It is known that under certain circumstances, Heart Period Variability (HPV) could be a measure of actual mental effort. This paper gives a short overview of applications of HPV in ergonomics in general and, based on empirical evidence intends to prove that this methodology, after a careful adaptation, could be powerful technique for monitoring mental effort in HCI. The paper outlines the main components of the INTERFACE testing workstation and the related methodology for investigatingamong others-users mental effort. A detailed application example is also provided.