In this article the authors describe a novel way to conduct user studies via the combination of a physiological and an observational information channel. The method enables not only the quantification of arousing emotional states but also their disambiguation into positive or negative instances. The physiological channel targets sympathetic responses and is materialized as a perspiratory signal extracted from thermal imagery of the perinasal area. The observational channel is materialized via decoding of facial expressions. However, while such decoding is usually performed in the visible spectrum, the authors have developed an algorithm to carry this out in thermal imagery instead. Thus, thermal imaging is used for both physiological and observational analysis. The potential of this dual unobtrusive methodology is demonstrated with some examples from a stress study, where users (surgeons in this case) interact with laparoscopic training boxes.
['Avinash Wesley', 'Peggy Lindner', 'Ioannis T. Pavlidis']
Eustressed or distressed?: combining physiology with observation in user studies