Eye, Head and Torso Coordination During Gaze Shifts in Virtual Reality

Abstract

Humans perform gaze shifts naturally through a combination of eye, head and body movements. Although gaze has been long studied as input modality for interaction, this has previously ignored the coordination of the eyes, head and body. This article reports a study of gaze shifts in virtual reality aimed to address the gap and inform design. We identify general eye, head and torso coordination patterns and provide an analysis of the relative movements’ contribution and temporal alignment. We quantify effects of target distance, direction and user posture, describe preferred eye-in-head motion ranges and identify a high variability in head movement tendency. Study insights lead us to propose gaze zones that reflect different levels of contribution from eye, head and body. We discuss design implications for HCI and VR, and in conclusion argue to treat gaze as multimodal input, and eye, head and body movement as synergetic in interaction design.

BimodalGaze: Seamlessly Refined Pointing with Gaze and Filtered Gestural Head Movement

“…This has been observed to lead to less eye rotation and a comparatively larger contribution of head movement to gaze shifts [Kollenberg et al 2010;Pfeil et al 2018]. For this work, we specifically built on quantitative insight into eye, head and torso coordination from a recent study of gaze shifts in VR [Sidenmark and Gellersen 2019a]. That work informs the criteria we use to filter gestural head movement from head movement that is naturally coupled with gaze.…”

“…Natural head movements are used to further the range of the eyes or to move the eyes into a comfortable position [Tweed et al 1995]. Research has shown natural head movement occurs at the same time as, or a shortly after, the initial eye movement to maintain a comfortable eye-in-head position [Sidenmark and Gellersen 2019a]. If the head does not move within a certain time (t l ) after an eye movement we can assume that the head movement is gestural.…”

New Measures of Visual Scanning Efficiency and Cognitive Effort

“…In order to deeply understand visuo-motor behavior based on eye movement and driving data in an effective and controllable way, virtual reality is used in this paper, as has been done in many works [22]. A virtual environment ( VE ), including common straight, curved roads and buildings, is designed for the experimental study.…”

Better, Virtually: the Past, Present, and Future of Virtual Reality Cognitive Behavior Therapy

“…The entire concept of (HMD) VR relies on continuous head rotation tracking, making rotation a suitable user interface through the use of a crosshair that fixates eye gaze and synchronizes it (at least to same degree) with head rotation. In fact, human-computer interaction research has shown that head rotation provides an adequate proxy measure of eye gaze: gaze tends to focus around a rotation-controlled crosshair, and gaze shifts above 25°are typically accompanied by subsequent head movement with a lag of 30-150 ms (Sidenmark and Gellersen 2020). In general, head rotation data has seen very few published clinical applications beyond its immediate role in graphical presentation, either as a way of adapting the virtual environment (e.g., prompting a "Look up!"…”