Food texture manipulation by face deformation

Food texture plays an important role in the experience of food. Researchers have proposed various methods to manipulate the perception of food texture using auditory and physical stimulation. In this paper, we demonstrate a system to present visually modified mastication movements in real-time to manipulate the perception of food texture, because visual stimuli efficiently work to enrich other food-related perceptions and showing someone their deformed posture changes somatosensory perception. The result of our experiments suggested that adding real-time feedback of facial deformation when participants open their mouths can increase the perceived chewiness of foods. Moreover, perceptions of hardness and adhesiveness were improved when the participants saw their modified face or listened to their non-modified chewing sound, while both perceptions were decreased when participants were presented with both stimuli. These results indicate the occurrence of the contrast effect.