Definition: The term "tachyglossal" refers to a type of sensory mechanism in which a person's eyes are stimulated by the movement of their feet. This phenomenon is known as vestibular synesthesia, and it occurs when two different sounds or sensations are perceived at the same time. It can be caused by changes in the rhythm or frequency of movement, such as when someone moves their feet while listening to music, or when they move their toes during a certain activity, such as walking or running