Thermal Masking Across the Human Body: Patterns, Pathways, and Perceptual Boundaries

Thermal masking, a vibration-induced illusion in which concurrent tactile input induces a vivid thermal sensation at the tactile site, is a promising mechanism for wearable interfaces and extended reality because it can deliver rich thermal feedback with minimal hardware. While prior work has examined this phenomenon on limited body parts, its expression across the full body remains under exploration. We present four studies mapping thermal masking across eight regions: head, face, neck, arms, hands, torso, legs, and feet. Results show that masking strength is location-dependent, producing perceptual patterns that align primarily with somatosensory pathways rather than proximity. On smaller regions such as the fingers, masking was localized, while on larger areas such as the torso and neck, it extended more broadly. Dorsal–ventral and inter-body tests revealed viable pairings and perceptual boundaries. These findings provide the first comprehensive atlas of body-wide thermal masking, advancing understanding and guiding efficient thermal–tactile interface design.