Neurophysiological experimental facility for Quality of Experience (QoE) assessment

The human brain is the epicenter of every human action, thus neurophysiology will pave the way for understanding human behavior and cognition and their interplay with Quality of Experience (QoE). Recent advances in neurophysiological monitoring tools have allowed useful QoE constructs to be measured in real-time, such as human cognition, attention, emotion, fatigue, perception and task performance. In this paper, we describe a multimodal neurophysiological experimental facility recently implemented for QoE evaluation. A description of the facility and the available equipment is presented. Results of three recent studies are also presented, thus showing that neurophysiological correlates can be obtained for i) natural speech and ii) synthesized speech QoE perception, as well as iii) image preference characterization for multimedia QoE evaluation.

I. Introduction

Quality of Experience (QoE) is a fast emerging multidisciplinary field based on social psychology, cognitive science, economics, and engineering science, focused on understanding overall human quality requirements [1]. Some of the examples of its different sub-factors or constructs are perception, cognition, emotion, judgement, satisfaction, happiness and acceptability. ITD - T defines QoE as “the overall acceptability of an application or service, as perceived subjectively by the end-user” [2]. Normally users manifest their subjectivity through their comments, opinions and thoughts. And that is normally quantified into numerical and interpretable values by conducting user studies, surveys and interviews. In addition to subjective assessment of QoE, there is an emerging trend to objectify QoE by capturing human physiological and cognitive information. The objective QoE factors are based on human physiology, psychophysics and cognitive systems [1], [3] which provide precise information about human cognition and neuronal activities. QoE factors can further be divided into different sub levels for instance level of service (ease of use, joy, feeling), level of interaction (communication efficiency, naturalness), level of direct perception(involvement, localization, distortion), and the level of the usage situation (accessability and the stability) [4]. These different constructs are the result of neuronal activity exhibited at low level sensory processing and/or high-level cognitive processing [4].