Human Echolocation: Blind People, Clicks and Daniel Kish

Human echolocation is the skill of sensing silent objects and the layout of a space from echoes: a person makes a sound, such as a tongue click, a footstep or a cane tap, and listens to how it bounces back. Some blind people use it alongside a white cane or a guide dog (Thaler et al., 2023). As one brain-imaging study put it, "A small number of blind people are adept at echolocating silent objects simply by producing mouth clicks and listening to the returning echoes." (Thaler, Arnott and Goodale, 2011). It is a hearing skill, not a kind of sight (Kolarik et al., 2014), and not every blind person uses it. But research shows that blind and sighted adults can learn it, and that it works best as one more tool next to the cane.

Key points

• Echolocation means getting spatial information from echoes. It is "probably best known from bats, but people can echolocate as well" (Thaler et al., 2023).
• Expert echolocators use tongue clicks (Thaler et al., 2017), but echoes from footsteps, cane taps and finger snaps can also be used (Thaler, 2013).
• Nobody knows how many blind people echolocate. Anecdotal reports suggest 20 to 30% of totally blind people may use it (Thaler, 2013).
• Daniel Kish is an echolocation teacher who is blind himself. He lost both eyes to retinoblastoma by 13 months of age and founded World Access for the Blind in 2000 (World Access for the Blind).
• Experts can be very precise: in one study they noticed a sideways shift of about 1.2 degrees between two objects (Teng, Puri and Whitney).
• Echoes activate brain areas usually tied to vision in blind experts (Thaler, Arnott and Goodale, 2011), and 10 weeks of training increased that activity in blind and sighted learners (Norman, Hartley and Thaler, 2024).
• It can be learned at any adult age tested: people from 21 to 79 improved in a 10-week program (Norman et al., 2021).
• It adds to the white cane, guide dog and orientation and mobility (O&M) training. It doesn't replace them.

What is echolocation?

"Echolocation is the ability to obtain spatial information from sound echoes," write the authors of a 2023 study (Thaler et al., 2023). A sound travels until it hits a surface and reflects back, and "The sound reflection, or echo, carries information about the nature and arrangement of the surface it bounced back from." (Thaler et al., 2023).

Researchers split it into two kinds (Norman et al., 2021):

• Passive echolocation: listening to echoes of sounds made by something else, such as the ambient sound around you or another person talking.
• Active echolocation: making your own sound and listening to its echoes. In the study's words: "For active echolocation, one makes their own emissions and uses echoes arising from those, e.g., echoes from one's own mouth clicks, footsteps, cane taps, etc."

Echolocation in bats and dolphins

Many bats and some marine mammals use echolocation to navigate and hunt (Teng, Puri and Whitney). The word itself was first used by the scientist D. R. Griffin in 1944, to describe how bats navigate and find prey in the dark. His paper was titled "Echolocation by blind men, bats and radar" (Kolarik et al., 2014).

• Bats: "Bats navigate and find insect prey using echolocation. They produce sound waves at frequencies above human hearing, called ultrasound." (National Park Service).
• Dolphins: bottlenose dolphins hunt by sound too. "They use passive listening and/or high frequency echolocation to locate prey." (NOAA Fisheries).

Human clicks are different from bat calls. The clicks of expert human echolocators are very brief, with peak frequencies of 2 to 4 kHz and some energy also at 10 kHz (Thaler et al., 2017).

Can humans echolocate?

Yes. "Even though echolocation is primarily associated with bats, it is by now well established that humans are able to use it as well" (Norman et al., 2021).

The skill was noticed long before anyone could explain it. In 1749, the French philosopher Denis Diderot described a blind person avoiding obstacles (Thaler, 2013). "Diderot believed that the proximity of objects caused pressure changes on the skin, and this led to the concept of 'facial vision'" (Kolarik et al., 2014). For a long time people talked about "facial vision" or an "obstacle sense", as if blind people felt objects with their face.

Experiments in the 1940s settled it. A series of studies at the Cornell Psychological Laboratory, starting with Supa and colleagues in 1944, "established that facial vision was actually an auditory ability" (Kolarik et al., 2014). In other words, people were hearing the objects, not feeling them. By the 1940s and 1950s it had also become clear, as one researcher puts it, that "anybody with normal hearing can learn it" (Thaler, 2013).

How blind people use echolocation

Tongue clicks

The experts in these studies use mouth clicks (Thaler et al., 2017). The click is "produced by rapidly moving the tongue in the palatal area behind the teeth" (Kolarik et al., 2014). It is short and sharp. A 2011 study described it like this: "The echolocation click produced by such individuals tends to be short (approximately 10 ms) and spectrally broad" (Thaler, Arnott and Goodale, 2011). Later, more detailed recordings of three blind experts measured clicks of about 3 milliseconds; the sound level was fairly even within a 60 degree cone in front of the mouth and dropped gradually outside it (Thaler et al., 2017).

The echoes that come back can tell an expert a lot: "For the skilled echolocator, the returning echoes can potentially provide a great deal of information regarding the position, distance, size, shape and texture of objects" (Thaler, Arnott and Goodale, 2011).

For the two experts in that 2011 study, it was part of daily life: "Both EB and LB use echolocation on a daily basis, enabling them to explore cities during travelling and to hike, mountain bike or play basketball." (Thaler, Arnott and Goodale, 2011).

Footsteps, cane taps and other sounds

Clicks are not the only option. "Some people can echolocate by making sonar emissions (e.g., mouth-clicks, finger snaps, feet shuffling, humming, cane tapping, etc.) and listening to the returning echoes." (Thaler, 2013). Echoes can also come from ambient sound that the person didn't make, which is the passive kind (Thaler et al., 2023).

Clicks seem to give more information, though. "Laboratory research has shown that click-based echolocation provides sensory advantages above and beyond passive echolocation via ambient sound fields" or using footsteps or cane taps (Norman et al., 2021).

Do all blind people use echolocation?

No. There is no official count. "To date there are no statistics available about how many blind people use echolocation, but anecdotal reports in the literature suggest that perhaps between 20 and 30% of totally blind people may use it" (Thaler, 2013). A later paper is blunter: "Only a small number of people with VI use click-based echolocation." (Thaler et al., 2023).

Ability varies too. A review of the research says "these skills vary substantially across individuals, and not all blind people can echolocate." (Kolarik et al., 2014).

There may also be a social reason. "Another possibility for the limited popularity of echolocation might be concerns about social stigma." Some blind people may not want to make clicks or other sounds in public for fear of seeming odd, and blind children are often discouraged from an early age from behaviors that seem to have no purpose; the author suggests clicking could be discouraged the same way (Thaler, 2013). Blind people also differ in how much sight they have; for what that looks like, see what blind people see.

Who is Daniel Kish?

Daniel Kish is an American echolocation expert and teacher. His organization's biography says: "Daniel Kish was born in March, 1966 in Montebello, California. Diagnosed with retinoblastoma, which is an aggressive cancer of the retina, he lost one eye and then the other by the age of 13 months." (World Access for the Blind).

He started clicking as a toddler. The same page quotes Michael Finkel's profile in Men's Journal: "He came to it on his own, intuitively, at age two, about a year after his second eye was removed." (World Access for the Blind).

According to that biography (World Access for the Blind):

• Education: he earned two master's degrees, one in developmental psychology and one in special education, and wrote a thesis on the history and science of human echolocation.
• Certification: "He also holds two national certifications in Orientation and Mobility, COMS and NOMC. Daniel is the first totally blind individual to obtain both certifications." COMS and NOMC are the two US credentials for O&M specialists, explained in our white cane guide.
• Founder: "So in 2000, he started World Access for the Blind."
• Teaching: "Daniel has worked with over 1,000 blind students of all ages and backgrounds", the organization says.
• Book: he co-wrote a guidebook called Echolocation and FlashSonar.
• Talks: he spoke at TED in 2015.

Kish has also worked with researchers, and his organization lists studies he co-wrote (World Access for the Blind). The 2011 brain-imaging study did not name its two experts, but World Access for the Blind's science page says they were Daniel Kish and Brian Bushway (World Access for the Blind). The early-blind expert in the paper, EB, "had partial vision up to 13 months of age. At 13 months, his eyes were removed due to retinoblastoma" (Thaler, Arnott and Goodale, 2011).

For other blind people who made history, see famous blind people.

World Access for the Blind

World Access for the Blind is a California-registered nonprofit (World Access for the Blind). Today it also uses the name Visioneers: "Visioneers is a division of World Access For The Blind, a global registered charity" (World Access for the Blind), and its old address, worldaccessfortheblind.org, now leads to visioneers.org.

Its method starts with "a click and a stick" (World Access for the Blind):

• The click: "The “click” we call FlashSonar™, a refined form of echolocation that uses tongue clicks to send out sharp flashes of sound which reflect off near and distant shapes and surfaces"
• The stick: a cane it calls the Perception Cane, which it describes as lighter and longer than the white canes traditionally used by blind people.

The organization says Kish and his team have taught its approach "to over 15,000 blind persons, their families, instructors and community members" (World Access for the Blind). That is its own figure. It also describes its results in visual terms; the research papers in this guide describe echolocation as a hearing skill. Researchers have worked with the group: a Berkeley team recruited seven blind expert echolocators "with the aid of World Access for the Blind, a non-profit organization devoted to teaching echolocation techniques" (Teng, Puri and Whitney).

What research says about human echolocation

How accurate is it?

For experts, very. In the Berkeley study, "experts were able to discriminate horizontal offsets of stimuli as small as ~1.2° auditory angle in the frontomedial plane, a resolution approaching the maximum measured precision of human spatial hearing and comparable to that found in bats performing similar tasks." (Teng, Puri and Whitney). A later paper summed up the result as detecting a gap as small as 2 centimeters between two objects 1 meter away (Thaler, 2013).

The same study found that the earlier someone lost their sight, the sharper their echolocation tended to be: "Furthermore, we found a strong correlation between echolocation acuity and age of blindness onset." (Teng, Puri and Whitney).

What happens in the brain?

The 2011 study scanned the two experts with fMRI while they listened to recordings of their clicks and echoes. "These findings suggest that processing of click-echoes recruits brain regions typically devoted to vision rather than audition in both early and late blind echolocation experts." (Thaler, Arnott and Goodale, 2011). Two sighted people scanned for comparison did not show that extra activity in the visual area (Thaler, Arnott and Goodale, 2011).

A larger study in 2024 looked at learners, not experts. "Here, we trained 12 blind participants and 14 sighted participants in echolocation over a 10-week period, and used MRI in a pre–post design to measure functional and structural brain changes." After training, both groups "showed a training-induced increase in activation in left and right V1 in response to echoes", V1 being the primary visual cortex (Norman, Hartley and Thaler, 2024). This means the brain's visual areas take part in processing echoes. It does not mean the person sees.

Can sighted people learn echolocation?

Yes, with training. "Sighted people do not generally display echolocation abilities without training, probably because visual signals provide substantially more accurate spatial information." But "After training, normally sighted people are also able to use echolocation to perceive objects, and can develop abilities comparable to, but typically somewhat poorer than, those of blind people." (Kolarik et al., 2014).

The 2021 training study found the same: "We found that both sighted and blind people improved considerably on all measures, and in some cases performed comparatively to expert echolocators at the end of training." (Norman et al., 2021).

How long does it take to learn echolocation?

It depends on the goal. The most detailed training study we found was run at Durham University, in England, and published in 2021:

• The program: "Blind and sighted participants of various ages (21–79 yrs; median blind: 45 yrs; median sighted: 26 yrs) trained in 20 sessions over the course of 10 weeks in various practical and virtual navigation tasks." Each session lasted 2 to 3 hours (Norman et al., 2021).
• Age: "Overall, our results suggest that the ability to learn click-based echolocation is not strongly limited by age or level of vision." (Norman et al., 2021).
• The groups were small: 12 blind and 14 sighted people.

Experts have practiced far longer. In the Berkeley study, the six experts estimated their total practice, formal training plus daily use, at roughly 12,000 to over 200,000 hours (Teng, Puri and Whitney). The Durham team counted someone as an expert after more than 10 years of daily click-based echolocation (Norman et al., 2021).

Finding a teacher is the hard part. "Currently, training in click-based echolocation is limited to self-training by trial and error and/or training with another echolocator." (Thaler et al., 2023). To change that, a Durham University researcher ran 18 free, 6-hour workshops across the UK in 2018 for 201 visual impairment professionals. Of those who answered the follow-up, 98% said they had changed their professional practice (Thaler et al., 2023).

Does it help in daily life?

The training study asked its blind participants three months later. "In the follow up survey, all participants who were blind reported improved mobility, and 83% reported better independence and wellbeing." (Norman et al., 2021).

An earlier online survey of 37 blind people found that "people who use echolocation have higher salary, and higher mobility in unfamiliar places, than people who do not use echolocation." The author is careful about what that means: "The investigation was correlational in nature, and thus cannot be used to determine causality." (Thaler, 2013). In other words, echolocation may help, or people who already travel more may be more likely to echolocate.

What we don't know yet

Echolocation has limits that research is still mapping. "Background noise may make it difficult to perceive an object based on echoic information", and echoes in a room can blur the echo from the object (Kolarik et al., 2014). And "The consequences of hearing loss for echolocation abilities are currently unknown." (Kolarik et al., 2014).

Echolocation adds to the cane, the guide dog and O&M

Echolocation is not a replacement for the white cane or a guide dog, and the research shows it.

• Every echolocator in the survey also used a cane. "The majority of our participants (34 out of 37) use the long cane, and all participants who reported to echolocate, also reported to use the long cane." The author concludes: "This suggests that the benefit of echolocation that we found might be conditional upon the long cane being used as well." (Thaler, 2013).
• The training built on skills people already had. "All of our participants who were blind were competent long cane users and/or guide dog users prior to taking part in our training. Thus, everyone had previously already received training in orientation and mobility, and the effects that they experienced were on top of their already existing skills." (Norman et al., 2021). In the outdoor practice, "every participant who was blind was also asked to use their long cane", and a researcher walked within arm's reach to keep them safe (Norman et al., 2021).
• Researchers describe it as one tool among several. "Click-based echolocation can support mobility and orientation in people with vision impairments (VI) when used alongside other mobility methods." (Thaler et al., 2023).

World Access for the Blind also pairs the click with a cane (World Access for the Blind).

In the US, cane travel is taught by orientation and mobility specialists (white cane). In 2021, the Durham team wrote that "Echolocation is currently not taught as part of mobility training and rehabilitation for blind people", and argued that "it would make good sense to provide training in this skill as part of orientation and mobility instruction to people with vision impairments." (Norman et al., 2021). How the cane is used and how to get O&M training are explained in our guide to the white cane; guide dogs, in our guide to guide dogs; and phones, money and cooking, in how blind people do everyday things.

Where Braillito fits

Echolocation helps some blind people move through space; braille is a way to read and write by touch. Braillito, our app, teaches braille. It teaches the braille cells in lessons with exercises you play, with lives, levels and a daily streak: 59 lessons in 8 worlds in English. It also has a translator, a dictionary and a cell builder. It is meant for anyone learning the code, such as adults who are losing their sight (learning braille as an adult) or sighted family members of a braille reader (learning braille as a sighted person).

Braillito is a subscription with no free version; depending on the plan, it starts with a free trial or a discounted first period, if it's your first subscription (is Braillito free?). Get Braillito.

Frequently asked questions

Can humans echolocate?

Yes. Scientists consider it well established that people can echolocate. Some blind people use tongue clicks and the echoes that come back to sense objects and open spaces around them. Experiments in the 1940s showed that the old "facial vision" of blind people was really hearing.

How do blind people echolocate?

Expert echolocators make short, sharp tongue clicks and listen to how the sound bounces off things around them. Others use the echoes of footsteps, cane taps, finger snaps or the ambient sound around them. The echoes can carry information about where an object is, how far away it is, and its size, shape and material.

Who is Daniel Kish?

An American echolocation expert and the founder of World Access for the Blind, a California nonprofit started in 2000 and now also called Visioneers. Born in 1966, he lost both eyes to retinoblastoma by 13 months of age and began clicking at about age two. His organization says he holds both US orientation and mobility certifications, COMS and NOMC.

Do all blind people use echolocation?

No. There are no official statistics. Anecdotal reports suggest that perhaps 20 to 30% of totally blind people use it, and a 2023 paper says only a small number use click-based echolocation. Skill varies a lot from person to person, and some people avoid clicking in public.

Can sighted people learn echolocation?

Yes, with training. Sighted people don't usually echolocate on their own, because vision gives better spatial information. In a 10-week study, sighted adults improved considerably, and some reached the level of experts on certain tasks, though sighted people are typically somewhat less accurate than blind echolocators.

How long does it take to learn echolocation?

In a 10-week training study, blind and sighted adults aged 21 to 79 improved over 20 sessions of 2 to 3 hours each. Expert echolocators have practiced for many years: experts in one study estimated their total practice at 12,000 to over 200,000 hours.

Does echolocation replace a white cane or a guide dog?

No. In a survey of 37 blind people, everyone who echolocated also used a long cane, and the benefits found might depend on using both. Researchers describe echolocation as a tool used alongside the cane, a guide dog and orientation and mobility training.

Is human echolocation the same as bat echolocation?

The idea is the same: make a sound and listen to the echo. But bats use ultrasound, which is above the range of human hearing, while people use clicks they can hear, with most of their energy at a few kilohertz.