Sonification discourse has predominantly been concerned with the interpretation and display of data, but it has also been widely touted as an important tool for creating accessibility for people who are blind. The benefits of sonic alerts, earcons, and audified information for those with limited or no vision are obvious, but there is one sonification technique that is arguably even more useful: human echolocation. Through rigorous training, some blind individuals have learned to navigate the world with remarkable aptitude. Daniel Kish, the most notable proponent of human echolocation, lost his sight in his infancy but has gradually learned how to negotiate the world acoustically (Kish 2009). By emitting vocal clicks, Kish manages to negotiate the world with a grace that is incomprehensible to sighted people. Even more astonishing, he is able and has taught others to ride bicycles. He is also able to sense and describe objects around him in detail; with training and practice echolocation is not only able to reveal the presence and placement of objects but can also help a listener to discern size, texture, and density.
In that echolocation is a technique that uses sound to convey or relay information, it is consistent with the most basic definition of sonification. However, unlike other forms, it does not operate in the symbolic realm, creating representations of data or phenomena. Rather, it is a technique for emplacement, for an immediate experience of a space. The sounds that the echolocator produces and then receives do not represent or tabulate the world; they present it in its immediate plenitude. In the same way that the reflection of light off an object constitutes the unmediated experience of seeing, the reflection of sound off a thing constitutes an unmediated experience of hearing. ... While the sound that the FlashSonar employs has been arbitrarily chosen, the "image" of the world that the listener receives is not represented; it is immediate.