FAQ & Knowledge Base

Below we have grouped frequently asked questions into topics. These are questions that have arisen in the context of echolocation workshops and presentations.

FAQ Topics:

Echolocation Clicks

Echolocation and Hearing Loss

Echolocation and Partial/Residual Vision

Age related Questions, Children, Older Adults

Echolocation and the Brain

Echolocation Instruction – General Questions

Echolocation Instruction – Specific Practical Exercises

Echolocation Research Questions

FAQ about Echolocation Clicks

What if someone is worried/self-conscious about the clicks?

If someone is worried or self-conscious about the clicks it may prevent them from using echolocation. This issue can be the same for the long cane, for example. In the end, if people use a tool or not will depend on if they perceive it as useful or not. As an instructor you can facilitate people taking up the use of echolocation by (a) helping people to develop a good click; one which enables them to make a quieter click but that will still get them useful echo information. This way they may feel less worried about what other people think. (b) helping people to improve their ability to interpret the echoes, for example by providing guidance for exercises. This will help them to make use of the sounds that they hear and thus improve their skill level and confidence.

What is a good click?

A good click is a brief (~3ms long), sharp and ‘bright’ sound that can be made louder and quieter (depending on the situation). What you also want is that the clicking does not take too much effort (i.e. the clicking comes easily and is not hard work taking over all your concentration). You want the clicks to be consistent i.e. sound similar from one click to the next; this makes it easier to interpret any change in echo as a change in the environment, not a change in the click itself. All these features will develop with practice.

Do clicks differ from person to person?

Yes; even when people make excellent clicks, each person’s click is unique, just like their voice.

What if someone has dentures, tongue piercings or tongue problems?

This may impact on a person’s ability to make clicks using their palate and tongue. Thus, it is advisable to try out some other types of clicks or alternatively try if they can work better using a tool to make clicks, e.g. castanets.

How would you teach a child (or an adult) how to make a mouth click?

This will depend on the person’s natural tendency to make a good click and their ability to follow verbal instructions. For some children (or adults!) you do not have to teach much, as they just naturally make a good click. The first step in teaching can always be to simply demonstrate/provide some examples of good clicks; and encourage the student to try their own click and listen for what they produce. In some cases nothing more is needed. Yet, for some people copying by example does not suffice, and more work is needed (e.g. exercises for how to teach mouth clicks).

Are mouth clicks best for echolocation because they are self-generated sounds?

We think that mouth clicks are particularly useful for a variety of reasons: (a) they are brief (~3ms long), sharp sounds, that carry well across background noise, better than whistling or speech for example (b) they do not interfere with your breathing like whistling or speech for example (c) they keep your hands free (as opposed to finger snap or handheld clicker) (d) they can be modulated depending on the situation (i.e. start and stop clicking as you wish, or make louder or quieter clicks as needed) (e) they come from your mouth which is fixed in between your two ears, which makes it easy to interpret changes in the echoes as a change in the environment.

What if someone has difficulty with certain mouth or tongue movements?

If someone struggles making a good click naturally by copying an example of a good click (e.g. from their instructor), specific instruction is required (e.g. exercises for how to teach mouth clicks). It is possible that even with instruction someone may struggle making a good click with the palate and tongue. In this case it is advisable to try out some other clicks (e.g. exercises for how to teach mouth clicks) or to try out if they benefit from using a tool to make clicks, e.g. castanets.

FAQ about Echolocation and Hearing Loss

What if someone has hearing loss?

Even people with hearing loss may benefit from echolocation; but there are some things to consider. Research has shown that people who have no hearing at all (either permanently through complete hearing loss or temporarily through blocked ears) will not benefit from echolocation. Research has also shown, however, that people who have residual natural hearing and/or assisted hearing (e.g. hearing aids or cochlear implants) may benefit. Therefore, one has to assess the potential benefit on a case to case basis. In our experience certain practical exercises are particularly useful to determine if someone with hearing loss will benefit from echolocation. The practical exercises we recommend for assessing if someone will benefit are the panel exercises i.e. ‘absence-presence’ and ‘right-left’, as well as the corner exercises and the open door exercise.

What if someone only has hearing in one ear?

Even people with hearing in only one ear may benefit from echolocation, but there are some things to consider. For example, because they only have hearing in one ear they may have to scan more when they are exploring space. But in principle, echoic information will also be processed in a meaningful way by one ear only. Please also read the answer to the Question 'What if someone has hearing loss?'

Have you done echolocation research for people with hearing loss?

In our own research we have not systematically investigated the effects of hearing loss on echolocation, but research done by others has shown that whilst hearing loss does not automatically rule out benefiting from echolocation, it may have a negative impact on echolocation performance. Please also read the answer to the Question 'What if someone has hearing loss?' In our own research to date we have worked with two participants who have had hearing loss. The performance of these participants was not different from the rest of the participants who had normal hearing, demonstrating that echolocation can still work well with hearing loss.

FAQ about Echolocation and Partial/Residual Vision

If someone has residual vision does it impact on their ability to echolocate?

In our experience, in terms of people who use echolocation, there are quite a few people who have residual vision and use echolocation regularly, but only in situations when they feel that their vision alone is not sufficient. In our research to date we have tested these participants under blindfold. Most interestingly, in very recent research where we tested normally sighted people whose vision was simulated to not be very reliable, we have found that people combine information that they get from echolocation with the information that they get from vision. This means that they will use both together and combine them in a way that will increase their accuracy. Since the participants in this research were normally sighted people whose vision was only simulated to be not very reliable we still need to test this in people with residual vision.

Is echolocation research just focused on people who are totally blind?

No; we also work with people who may have some residual vision and also with normally sighted people. However, to date we have tested anyone with normal or residual vision under blindfold to ensure that they are only using the sound. Please also read the answer to the Question 'If someone has residual vision does it impact on their ability to echolocate?'

Have you done research with people with different amounts of residual vision?

Yes; but to date we have tested anyone with normal or residual vision under blindfold to ensure that they are only using the sound. Please also read the answer to the Question 'If someone has residual vision does it impact on their ability to echolocate?'

FAQ Age related Questions, Children, Older Adults

What is the youngest age you can start teaching echolocation?

The youngest child that we have taught was 3 years old; but you could start at an even younger age. A child might only be able to make their own effective mouth clicks once they are ~2 years of age, but they can learn echo-sounds and using echolocation with other noises pretty much from the day they are born (as long as they have hearing). For example, one can teach even infants the change in echo-sounds as they approach a wall, for example, by carrying them towards the wall whilst making sounds.

What is the oldest age you can start teaching echolocation?

The oldest participant we have taught was 79 years old. We do not think that age is a limit as long as the person is motivated. Since with older age hearing loss is more likely please also take a look at the questions and answers relating to echolocation and hearing loss.

Can children maintain concentration and attention in order to learn to echolocate?

Absolutely. It helps to make the exercises engaging and to keep it relevant to them. Please also read the answer to the Question 'What is the youngest age you can start teaching echolocation?'

Could you usefully affect a child’s development by training children from an early age?

To date there has been no research investigating the effect of age at which echolocation is learned on development. It is known from other research that the human brain is very adaptable to change at younger ages and during development. It has been shown that adults who lost their vision earlier in life, and as a consequence also learned echolocation at a younger age, have better acuity of echolocation. It has also been shown (but again only in adults) that people who use echolocation have better spatial competency, even in tasks that have nothing to do with echolocation. Based on the benefits of echolocation observed in adults, and research into brain plasticity and child development in other domains, we would therefore expect that the younger the age at which someone is introduced to echolocation the more this will benefit their development.

Have there been any research studies with children and young people?

To date there is no published research about echolocation and echolocation learning in children and young people. The youngest participant in our own research was 18 years old.

FAQ about Echolocation and the Brain

What parts of the brain are involved in echolocation?

Since echolocation is carried through hearing it activates hearing parts of the brain. However, it also activates parts of the brain that process visual information in sighted people, i.e. ‘visual’ parts of the brain.

Why are visual parts of the brain activated in echolocation?

One hypothesis is that these visual brain areas are best suited for the processing of spatial information. In sighted people this information is carried through vision most of the time. Yet, in people who are blind other senses, such as echolocation, may take over and provide a similar type of information which consequently engages the same brain areas.

Is there a difference in terms of brain activation for echoes between those who are blind from birth and late onset?

At present the sample sizes are too small to answer this question. But, based on the finding that also in sighted people who train in echolocation visual brain areas are activated in echolocation, we would expect little difference between those who are blind from birth and late onset. Please also read the answer to the Question ‘Will you see changes in visual areas of the brain if sighted people are trained?'

If people are proficient in Braille, does it affect the brain activation for echolocation?

We are not aware of any research that would have shown any link between brain activation for echolocation and Braille proficiency.

Will you see changes in visual areas of the brain if sighted people are trained?

Yes. Our research has shown that also in sighted people who train in echolocation visual brain areas are activated in echolocation. Thus, the blind and sighted brain seem remarkably similar in that respect.

FAQ about Echolocation Instruction – General Questions

How do you teach echolocation skills when someone is using their cane? For example if someone’s cane is detecting things in the exercises like an obstacle or an open door.

This in itself is not a problem. In fact, when beginning to train, the spatial information given by the cane (e.g. open door) whilst the student makes their clicks will help them associate the change in the sound with the change in the environment. If you have the feeling however that they are just relying on the cane, and not making their clicks and/or not paying attention to the sound, you can ask them to hold the cane by their side for the purpose of the exercise. Note that as the skill advances the distances at which clicks can detect landmarks, obstacles, doors etc. will be out of reach of the cane anyway, so this is less of an issue. To emphasize and accelerate this you can of course move the student farther away from whatever their target is during training so that the cane will not detect it anymore, but the sound will. Importantly, if you want to assess (other than teach) if someone is competent at using the echo sound (as opposed to relying on the cane) we suggest asking the student to hold the cane by their side for purpose of the assessment and to complete the exercise using only the clicks. To ensure that this can be done safely, you could ask the student to use upper body protection when not using the cane.

How do you teach echolocation skills when someone is using their dog? For example if someone’s dog is detecting things in the exercises like an obstacle or an open door.

This in itself is not a problem. In fact, when beginning to train, the spatial information as signalled by the dog whilst he student makes their clicks will help them associate the change in the sound with the change in the environment. If you have the feeling however that they are just relying on the dog, and not making their click and/or not paying attention the sound, you can ask them to heel their dog for the purpose of the exercise. Note that as the skill advances the distances at which clicks can detect landmarks, obstacles, doors etc. will increase, so this is less of an issue. To emphasize this you can of course ask the student to heel their dog during training, so that they have to rely on the sound. Importantly, if you want to assess (other than teach) if someone is competent at using the echo sound (as opposed to relying on the dog) we suggest asking the student to heel the dog for purpose of the assessment and to complete the exercise using only the clicks. To ensure that this can be done safely, you could ask the student to use upper body protection when not using the dog.

Does echolocation require people to be standing/walking? (Thinking of people with balance issues and/or using a wheelchair for example).

No; this is not a requirement. Echolocation only requires that the person can make their own sound either using their mouth and tongue or for example using castanets or clickers etc. Apart from that it works regardless of how a person moves around. In fact, if someone has a wheelchair that may require both hands to steer echolocation using mouth clicks can be very helpful because it keeps the hands free.

Is it best to teach echolocation with or without the long cane?

We advise teaching echolocation alongside other mobility methods and tools someone may be using; including, but not limited to, the long cane. If you are teaching the long cane, just introduce mouth clicks and echolocation at the same time. Teaching a click and doing some panel exercises to teach what to listen for will take a bit of extra time in the beginning. But, along the way it is actually going to save time, because it will make it easier for the student to orient themselves and to keep track of where they are in space and to map and understand the space they are moving through.

How do I go about integrating echolocation into my practice?

You can use any of the practical exercises suggested on our website and/or covered in our workshops. These are also adaptable to various scenarios and exercises that you might be doing anyway when you are teaching long cane skills for example. You can also refer the student and their family to the webpage and they can check out the materials themselves for their own study and guidance.

How would you integrate the exercises into real life?

Real life is actually the best exercise. We suggest encouraging your student to use the click and the echoes when they are going about their daily activities, just like you would tell them to do with the long cane. This will help them develop their click and over time they will build their echolocation repertoire. Without using echolocation in daily life the skill will not fully develop.

Is it best starting in an unfamiliar environment?

We suggest going about this like with other mobility skills you may teach. What environment (familiar or unfamiliar) works best will depend on the student, as well as what is available to you. It does not really matter, as long as the student engages with the clicks and echoes.

What if someone is using background noises or other environmental indicators rather than click-echoes to complete a task?

If you suspect that this is the case it would make sense to change the exercises in a way that will reduce these other sources of information to encourage the student to engage with the echoes. For example, if a draft gives away a door opening, just try approaching it from the other side where the draft is less noticeable. Or when there are other sounds that give it away try to find a location where the sound is less of an issue. Being mindful of these other sources of information will enable you to create situations that will accelerate and maximize learning. In real life these sources of information are available at times, but the point of any training is to focus on the element that is new; here that is the echoes.

Should head movement be done in a systematic way when searching/exploring?

Any exploratory movement should serve its purpose. Thus, if someone is searching for something above head level the head should be moved up, whilst if they are looking for something at head level but possibly to the right or left, they should rotate the head from left to right. Other than that the way in which a person moves will also depend on their own preferences and movement range. Practical exercises like the exploration exercise will help people get a sense of which sort of movements are helpful for them during echolocation.

Do people have to be encouraged to scan?

This will depend on the individual. Some may have to be encouraged, for others it comes naturally. Practical exercises like the exploration exercise will help people get a sense of which sort of movements are helpful for them during echolocation, and as an instructor you will get a sense of your student needing encouragement or not. Read also the answer to the Question 'Should head movement be done in a systematic way when searching/exploring?'

Would clicks work for over-hanging tree branches?

Yes; but if it is a single branch that is small (e.g. thickness of a finger) it will be hard to detect.

Do you get a reflection of sound back from poles?

Anything that is round will be harder to detect with echoes than flat surfaces or surfaces that are hollow, like the inside of a bowl or a corner. But in principle one can of course also hear objects that are round, like poles. A pole that is the thickness of a finger or smaller will be very hard to detect when out and about.

What happens if hard objects are covered in fabric e.g. carpet?

Soft materials like carpet or fabric absorb sound. Thus, covering anything in a soft material will make it harder to detect with echoes.

Is it difficult to echolocate in a busy street?

A busy street will be harder to navigate with echolocation not only because it is busy, but also because it is noisier. To echolocate effectively in noisy environments one has to be able to make louder clicks. Apart from that echolocation works well even in the presence of background noise.

Why is echolocation useful for detecting obstacles at head level, but less useful for ground level obstacles?

The acoustic energy from the click spreads mainly around head level. Thus, if the head is held up, the click will project to the front of the head making it easy to pick up echoes from objects at head level, but not from objects on the ground. Furthermore, the ground itself is a large reflector, so the ground itself may mask reflections of obstacles on the ground.

What about the acoustic information you get from the cane?

The cane can be used to make sounds for echolocation (e.g. by tapping). This can be useful, but because the sound emanates from the cane tip on the ground it is less effective than mouth clicks for dealing with space at head level. Please also read the answer to the Question 'Why is echolocation useful for detecting obstacles at head level, but less useful for ground level obstacles?'

Should people still use their cane and/or guide dog when doing the practical exercises?

Yes; we recommend that they are used together. Please also read the answer to the question ‘How do you teach echolocation skills when someone is using their cane? For example if someone’s cane is detecting things in the exercises like an obstacle or an open door’ or ‘How do you teach echolocation skills when someone is using their dog? For example if someone’s dog is detecting things in the exercises like an obstacle or an open door’.

FAQ about Echolocation Instruction – Specific Practical Exercises

Should people move their heads for open door exercises or click straight ahead?

We suggest that people carry themselves in the same way they would naturally behave in a situation that would require them to locate an open door. In most cases this will be clicking straight ahead until the open door is found, and then turning into the door to walk through it or to check if it is the correct room.

How are the panel exercises helpful for someone with a visual impairment?

The panel exercises teach people what to listen for. If someone has never used click based echolocation they are sometimes not sure what exactly it sounds like when they hear an echo. The panel exercises help with that. This is why they are good starting point. The panel exercises can also be used in different acoustic environments to teach how different acoustic environments affect what echoes sound like and how easy/difficult it can be to work with echoes and how to best adapt one’s click to work effectively across various environments. However, to really make use of echolocation one needs to go beyond panel exercises and introduce advanced skills.

Where is the best place to practice the tasks?

We suggest practicing exercises in as many environments as possible to develop competency across varying environments.

When there is no panel, what should we use to practice?

You can use anything that is made from hard material (wood, hard plastic, glass, porcelain, metal, etc.) and that is large enough, e.g. large dinner plates, coffee trays.

Should people still use their cane and/or guide dog when doing the practical exercises?

Yes; we recommend that they are used together. Please also read the answer to the Question ‘How do you teach echolocation skills when someone is using their cane? For example if someone’s cane is detecting things in the exercises like an obstacle or an open door’ or ‘How do you teach echolocation skills when someone is using their dog? For example if someone’s dog is detecting things in the exercises like an obstacle or an open door’.

FAQ about Echolocation Research

What are the ages of the participants in your research?

Our youngest research participant to date was 18 years old, and the oldest was 79, and a range of ages in between. The reason we have not worked with even younger or older participants is that the opportunity has not arisen yet (i.e. no one younger than 18 or older than 79 has inquired if they could take part).

Is your echolocation research just focused on people who are totally blind?

Have you done research with people with different amounts of residual vision?

Are people blindfolded in your research?

To date we have tested anyone with normal or residual vision under blindfold to ensure that they are only using the sound. Please also read the answer to the Question 'If someone has residual vision does it impact on their ability to echolocate?'

Are the sounds you are using self-generated?

In our research we use both self-generated sounds (i.e. people make their own clicks) but we also use sounds that are artificially made (e.g. clicks or other noises made by loudspeakers).

What do you quantify as an expert echolocator?

We use a combination of criteria to quantify someone as an expert: (a) duration of use of echolocation use (more than three years of use) (b) regularity of use (usage must be daily) and (c) task performance (i.e. people must be very good at the task that we ask them to do, for example they must be very accurate at localizing).

Have you done echolocation research for people with hearing loss?

In our own research we have not systematically investigated the effects of hearing loss on echolocation, but research done by others has shown that whilst hearing loss does not automatically rule out benefiting from echolocation, it may have a negative impact on echolocation performance. Please also read the answer to the Question 'What if someone has hearing loss?' In our own research we have to date worked with two participants who have had hearing loss. The performance of these participants was not different from the rest of the participants who had normal hearing, demonstrating that echolocation can still work well with hearing loss.

If people are proficient in Braille could they have more ability for echolocation?

We are not aware of any research that would have shown any link between echolocation ability and Braille proficiency.

Is there a link to cognitive ability?

We are not aware of any research that would have shown any link between echolocation ability and cognitive ability.

Is there any research where other sounds are introduced when someone is echolocating e.g. traffic noise?

In our research we have shown that people can compensate for the presence of background noise with increased level of echolocation click emissions. This work was based on echolocation tasks where people listen to sounds over headphones. We are working on paradigms where we introduce noise while people echolocate in a natural environment.