Gaze+Mouth: Gaze-Directed Tongue Input with Intraoral Device for Selection in XR

Extended reality (XR) headsets featuring gaze-tracking enable hands-free selection via explicit dwell or integration with other modalities. This paper demonstrates the novel hands-free interaction technique Gaze+Mouth, which combines eye-gaze for pointing with an intraoral tongue gesture for selection. We implement the technique using a wearable mouthpiece and conduct a user study (N=16) comparing Gaze+Mouth to the established Gaze+Pinch technique. Results show that while Gaze+Pinch is significantly faster, Gaze+Mouth achieved a comparable level of accuracy. This suggests that intraoral input is a viable channel for reliable hands-free selection in XR, offering a new modality for situations where users’ hands are occupied or when an alternative is desired.