Echolocation: Using Your Ears to Help You “See”

You can view Rowan’s video at YouTube.

Rowan, an 18-month-old German Spitz dog, was born without eyes, a rare condition known as anophthalmia. His owner Samantha Orchard, a dog breeder in the United Kingdom, was “stunned” when she realized that Rowan was using echolocation to navigate his environment – by barking and then listening to the echoes created by his bark to determine his location in relation to his surroundings. You can read more about Rowan at the Small World News Service.

Human Echolocation

It’s not Rowan I’m primarily interested in, however; rather, it is human echolocation that fascinates me. According to Wikipedia,

Human echolocation is the ability of humans to detect objects in their environment by sensing echoes from those objects. This ability is used by some blind people to navigate within their environments. They actively create sounds by tapping their canes, lightly stomping their feet, or making clicking noises with their mouths.

By interpreting the sound waves reflected by nearby objects, a person trained to navigate by echolocation can accurately identify the location and sometimes size of nearby objects and not only use this information to steer around obstacles and travel from place to place, but also detect small movements relative to objects.

VisionAware discusses echolocation as a component of maximizing hearing, touch, smell, and taste when learning to function independently with vision loss:

If you concentrate on what you are hearing, and where sounds are coming from, you will be able to gain more information about your surroundings and begin to feel safer and more comfortable. For example, try this exercise to help you locate an open doorway in your home:

  • Walk slowly down any hallway in your home.
  • As you walk, you will sense a “closed-in” feeling until you reach an open doorway.
  • At that point, you will probably experience a sense of “openness” on your left or right side, depending on which side has the open doorway.

Also, rooms that are varying sizes will sound different from one other. A bathroom, for example, is usually small and contains hard surfaces, such as tiles and porcelain that can cause sounds to bounce and “echo.” A living room is larger, with rugs and soft furniture that can absorb and muffle sounds.

As you approach your entry door, especially if it is located in a foyer, you may experience a “closed in” feeling or sensation. This occurs because sounds are reflected from three very close walls. In a living room or larger space, you’ll notice that sounds suddenly “fall away,” since they take longer to reflect from wall to wall. The area around you will now feel more spacious and open.

New Research on Echolocation

A new study, entitled Identification of the lateral position of a virtual object based on echoes by humans, published in the June 2013 issue of Hearing Research, examines how hearing, and echoes, can help blind people with spatial awareness and navigation. The study also examined the possible effects of hearing impairment and how to optimize echolocation ability to help improve independence and quality of life of people with visual impairments.

Here is more information about the study from Science World Report:

…researchers conducted a series of experiments with both sighted and blind human listeners. They used a “virtual auditory space” technique in order to investigate the effects of the distance and orientation of a reflective object on ability to identify the right-versus-left position of the object.

The researchers used sounds with different bandwidths and durations, from 10 to 400 milliseconds. In addition, they used various audio manipulations in order to see which aspects of the sounds were important. The virtual auditory space allowed researchers to remove positional clues unrelated to echoes, such as footsteps and the placement of an object, and to manipulate the sounds in ways that wouldn’t be possible otherwise.

They found that both sighted and blind people with good hearing showed the potential to use echoes to tell where objects are. That said, the ability to hear high-frequency sounds is required for good performance, so those with common forms of hearing impairment probably won’t be able to use the technique.

Blind Persons Have Been Using Echolocation for Many Years

Although I am interested in, and grateful for, this new research, it’s important to note that blind persons have been using echolocation, with great skill, for many years.

Ben Underwood

In 2007, Ben Underwood was featured in a People magazine profile. Ben was totally blind after retinal cancer claimed both of his eyes at age three.

When he was five years old, Ben discovered echolocation and learned to perceive and locate objects by making a steady stream of sounds with his tongue, then listening for echoes as they bounced off the surfaces around him. He used this skill to participate in running, rollerblading, skateboarding, basketball, and foosball. Ben died on January 19, 2009 at age 16, from the same cancer that claimed his vision.

Daniel Kish

Photo of Daniel Kish, President of World Access for the Blind, leading a group of blind hikers along a steep mountain trail. Photo credit: Volker Correll for World Access for the Blind

To learn more about echolocation, I recommend contacting Daniel Kish (pictured at right, leading a group of blind hikers), the founder and president of World Access for the Blind, an organization that provides instruction in FlashSonar (echolocation), mobility, and life skills to blind youth and adults.

Daniel, who also lost his vision from retinal cancer when he was 13 months old, has developed a wide array of echolocation techniques and leads energetic, no-holds-barred hiking, mountain biking, and wilderness expeditions. World Access for the Blind believes that recreational activities are valuable ways for blind persons to build confidence, improve their navigation skills, and fully participate in society.

Additional Information

Guest blogger Marta Fonmudeh, M.Ed, an Orientation and Mobility Specialist with Vision Australia, writes about teaching echolocation to “Annie,” a 50-year-old woman who experienced “a new way of seeing” after embracing Daniel Kish’s teaching methods.