Quality Assessment of Interaction Techniques in Immersive Virtual Environments Using Physiological Measures

This paper presents a new methodology for quality assessment of interaction techniques in immersive virtual environments, based on the study of the relationships between physiological measures and usability metrics using multivariate data analysis. Our methodology defines a testing protocol, a normalization procedure and statistical techniques, considering the use of physiological measures during the evaluation process. A case study comparison between two 3D interaction techniques (ray-casting and HOMER) shows promising results, pointing to heart rate variability, as measured by the NN50 parameter, as a potential index of task performance. Besides, this study also shows that heart rate (HR) and skin conductance (SC) measures reflect the user's task performance during the interaction process. Despite these results, this work reveals that physiological measures still cannot be considered as substitutes of evaluation metrics for 3D interfaces, but may be useful in the interpretation and understanding process of them. Discussions also indicate the further studies are needed to establish guidelines for evaluation processes based on well-defined associations between human behaviors and human actions realized in 3D user interfaces.