Illustration of the acoustic pattern of mouth clicks for human echolocation created by a computer model. Human echolocators "see" their worlds through sound, and thanks to a new computer model, you can too. Using math and painstaking experiments, a group from the UK modeled how the sounds from the nuanced mouth clicks of human echolocators travel around a room. Their findings, reported in PLOS Computational Biology, could yield devices that make "smart" radar maps that reveal the physical features of objects in the environment, like their texture or hardness, based off sounds. "One motivation was basic curiosity," said Lore Thaler, a neuroscientist at Durham University. "We know very little about the mouth clicks people make when they echolocate.

Some people who are blind can echolocate like bats, making clicks with their mouths that help them understand the environment around them. Now researchers are beginning to understand how this works, so non-sighted people may one day be able to learn the technique. While many people who are blind get information from ambient echoes, only a few make noises themselves to echolocate. Some, such as Daniel Kish (pictured), are so proficient they can draw a sketch of a room after clicking their way around it, or even go mountain biking along unfamiliar routes. Previous research revealed that this human echolocation involves some brain areas that are used for vision in sighted people.

Daniel Kish sees more than you might expect, for a blind man. Like many individuals deprived of sight, he relies on his non-visual senses to perceive, map, and navigate the world. But people tend to find Kish's abilities rather remarkable. As a child, Kish taught himself to generate sharp clicking noises with his mouth, and to translate the sound reflected by surrounding objects into spatial information. Perhaps you've seen videos like this one, in which Kish uses his skills to navigate a new environment, describe the shape of a car, identify the architectural features of a distant building--even ride a bike: Impressive as his abilities are, Kish insists he isn't special. "People who are blind have been using various forms of echolocation to varying degrees of efficiency for a very long time," he says.