Identifying Language-induced Mental Load from Eye Behaviors in Virtual Reality

Abstract

We compared content-independent eye tracking metrics under different levels of language-induced mental load in virtual reality (VR). We designed a virtual environment to balance consistent recording of eye data with user experience and freedom of action. We also took steps towards quantifying the phenomenon of not focusing exactly on surfaces by proposing ''focus offset'' as a VR-compatible eye metric. Responses to conditions with higher mental load included larger and more variable pupil sizes and less fixations. We also observed less voluntary gazing at distraction content, and a tendency of looking through surfaces.