Development of a game system for tongue motor function training

The tongue is an extremely important organ for eating and pronunciation. However, age-related functional decline can lead to impaired pronunciation and an increased risk of aspiration during meals, which in turn affects daily life. Although tongue movement training and rehabilitation are conducted in nursing and medical care settings, quantitative evaluation is rarely performed. Therefore, we have developed a tongue-operated joystick device for tongue movement training and rehabilitation. This device can sense both horizontal and vertical manipulation distances and forces. In addition, its viscoelastic resistance is adjustable, allowing for the individual adjustment of training intensity. Furthermore, to encourage continuous training, we have developed a dedicated game that works in conjunction with the device. After a certain period of tongue training using this device and game, the range of motion, strength, and gliding function of the tongue improved, confirming the usefulness of the system. To further improve tongue function, the device was newly improved to accommodate the back-and-forth movement of the tongue, and its performance was confirmed. The improved device was found to be effective in tongue training because it could accurately estimate the manipulation force and trace tongue movements up to 5 Hz.