How The Blind Can See With Sounds (& me too)

Many people know that creatures like Bats and Dolphins navigate by sonar like systems but is unknown to many is that blind humans can do so too.  In recent years, there have been more and more documentaries and reports on this phenomenon and the vast majority of people seem very much shocked by this.  How can a blind person ever play football or basketball or ride a bike or skateboard down an urban street?

I must say; this scientific revelation was not in anyway a shock to me.  You see I am partially sighted and as with many disabilities, my brain has found a way to compensate for this as best as it can.  With me, it is fantastically improved hearing.  I have hearing that is a cross between Superman and a Spider-sense or as I used to think to myself an X-Men style step in human evolution.

Noise can and does drive me crazy.  I hate the constant roar of the traffic on the major roads several miles from my home that I hear day and night even in my house with the windows shut.  I know when neighbours on both sides of my house go to the toilet, sometimes it even wakes me up.  The increased hum from the neighbours fridge freezer every few hours also can wake me up or if it happens in the daytime, I can hear it in my office/writing room despite it being on a different level and through 3 or 4 walls.

It’s always been this way.  At school in a science class one day, a teacher had a device that emitted sound at certain frequencies.  Every ten seconds he would increase it by a kHz.  Of course, I could hear it well after the other children.  Eventually, we reached the range that only dogs could hear it.  My teacher was convinced that I was watching him switch the transmitter on so he would hide it under the lab bench and pretend to switch it on but I always knew he was faking it and similarly I knew when he put it on.  These days we have ultra-sonic cat-scarers in our garden to stop cats from defecating on the lawn.  These devices that only those under three can hear, along with cats and dogs are really annoying I can tell you.  They don’t make me run out of the garden but I hear them and they give me a headache after 5 minutes or so.

I also hear a lot of weird noises, sounds from inside other people’s bodies, mechanical noises which I guess I’m not meant to hear.  Conversations 100 metres / yards down the street.  I remember when I got my first job and I was working in an office block with five levels on it.  I would try and do the pick-up call thing for telephones that were ringing two floors above me.  We worked in the Defence industry too and these buildings were well put together.

It’s hard to describe just what the feeling is like.  Just as it would be hard to describe the difference in colours between red and blue to a blind person who didn’t know what a colour is.  How can I describe what super-hearing is like?   If you’ve ever seen the episode of Star Trek TNG where the empathic Counsellor Troi is driven mad because she can’t shut out the thoughts of other people, then that is sometimes how it feels only not voices but sounds generally.

Of course, it has it benefits too.  I can hear the most amazing things which I don’t think many others can; they certainly don’t appreciate it like I do.  I love sitting in the garden and listening to the individual insects flying around; I don’t mean next to my ears but 10-20 feet away.  Sometimes the wingbeats of the creatures.  I can be reading on the garden bench and I get distracted by a noise.  What can it be?  An overhead plane, a car engine?  Or maybe an ant crawling over a blade of grass or a ladybird sat on the leaf of a rose-bush. I can hear the individual blades of grass moving either by wind or by whatever makes grass move on its own.  Hearing one or two is incredible but walking bear foot on the lawn and hearing dozens or hundreds of tiny leaves moving is something like standing on a beach and listening to the waves crash in, at least, it is to me.

Apart from having this fantastic gift of hearing, I also have a rudimentary echolocation system.  More and more people are learning to use this by emitting a noise from their mouth.  I must say; I don’t do that.  Mine works by the echo of my body moving, either footsteps or my whole being.  Again, it ‘s hard to explain what this is like to you poor people with good vision and pathetic standard human hearing 🙂  It’s almost like being in a 1990’s computer or video game.  Where characters would walk along corridors and you’d think that doesn’t look 100% real but it is definitely very good.

I don’t use lights at all unless I need to see something that I can’t hear… like reading a book.  I get dressed in the dark; I make an early morning cup of tea in the dark.  I do several hours of stuff a day around the house in the pitch black.  Of course at home, I normally know where things are aside from when someone moves something or an Airbnb guest leaves a pair of shoes or a suitcase somewhere unexpected.  I guess sight isn’t quite as important to me as at some level whether obvious or deep-down, I can’t and don’t rely or use it as others do.

It works anywhere, though.  Outside in the dark or in a strange building in the dark.  I can hear where I am in a room, or a corridor.  I know where the doors are, the windows.  If there are paintings or objects on the wall.  Where the carpets are.  Sometimes I hear something weird and realise there is a wall hanging or things hanging off shelves or window sills.  It just changes the echo or indeed stillness of a room I just see it all in my head as if in a 3d virtual reality game which is ironic because of course I can’t see in 3d in real life.  To me, everything is as flat as on a 2d television set, so I don’t get 3D movies, and I definitely don’t pay 50% extra to see one with those stupid glasses that end up just making things normal 2d for me only in a darker and nauseous way.

In my previous job, I used to be the first person in the building.  My office was on the second floor and bizarrely most of the lights were not near the entrance.  For years, I made my way through a maze of corridors, stairs, swing doors, discarded boxes without banging into anything.  I would work on my PC in the dark until the next people came on and selfishly put the lights on.   Often I would have to go into the large warehouse, and there, lights were at the far end of the room. It was often not the safest place even in broad daylight with heavy machinery, boxes of equipment and sharp objects everywhere.  Sometimes there was barely room to put your foot on the floor.  That was challenging I admit, but I never banged into anything, I did several times swear in my head wondering what on earth something was and why it was put where it was and then, later on, I’d get to the light and realise that my guess was pretty accurate and my route as good as a sighted person in the day time.

Being partially sighted, I am still fortunate that I have one perfectly working eye and with my super-hearing, no-one ever thinks of me as being disabled, in fact, most people don’t have a clue.  The only things which are tiresome are not able to see 3d movies or those funny 80’s paintings where you look at the dots and see an image appear.  I always have to sit on the right to watch TV or the cinema.  I can’t always see everyone I am talking to and can’t steal a glance at someone in the street or on the train without moving my whole head which kind of defeats the purpose.  I often don’t bother looking over my shoulder when crossing a road, there is little point as if I do so, I won’t see anything and drivers will presume I know they are coming.  So I just let them think I am an idiot and trust they will stop.    Of course, I don’t employ this strategy in an obviously dangerous street.

People who are fully blind are increasingly using a technique similar to what bats and dolphins use, human echolocators navigate using audio cues given off by reflective surfaces in the environment. Few people know that this same technique can work for human beings.  It isn’t something everyone has to learn, like me and my extrasensory hearing, it comes naturally to some.

For centuries, researchers have been trying to find out how blind people compensate for their loss of vision. It was clear that some blind people occasionally were able to “hear” objects that were apparently making no sounds. But no one knew exactly how blind people did this. And although bat echolocation was documented in 1938, scientists didn’t become seriously interested in the phenomenon until the early years of the Cold War, when military funding made the research feasible. It turns out human echolocation is akin to active sonar and the kind of echolocation used by dolphins and bats, but less fine-grained. While bats can locate objects as small as flies, human echolocators report that objects must be much larger — about the size of a water glass — for them to be locatable.

Human Sonar

How Human Sonar / Echolocation works

Such a system isn’t a mere gimmick but instead can offer full spatial awareness and depth perception. Research indicates that the imagery of echolocation is constructed by the same neurology that processes visual data in sighted people. The information isn’t travelling down the optic pathway — the connection from the eyes to the brain — but it ends up in the same place. And some individuals who have gone blind later in life describe the experience as visual, in terms of flashes, shadows or bright experiences. It seems possible that echolocators have visual imagery that is similar to that of sighted people.

The increased ability to navigate via sound appears to be the result of sound processing in the brain, not merely increased acuity of hearing. One study showed that the blind and the sighted scored similarly on regular hearing tests. But when a recording had echoes, parts of the brain associated with visual perception in sighted people activated in echolocators but not in sighted people. These results showed how echolocators extracted information from sound that wasn’t available to the sighted controls.

For me, it is the distinctiveness of sounds that I hear which I enjoy, the preciseness.  Right now, the Airbnb guest is walking in the next room and I don’t just hear him but the underlay insulation carpet being pressed on by the regular carpet.  I can also hear that he is wearing socks and not shoes, slippers or in bare-feet.  So I have lost part of a world but I also have my own one.  I guess hearing all these subtle noises and hearing the detailed, minute but definite differences and appreciating them is my version of looking at a colourful painting or 3D movie.

On top of the guest and his walking I am currently being overwhelmed by the noise of cars, a bus about half a mile a way, someone who got a new sound-system at Christmas and blares out music every Saturday morning from across the field (so he isn’t close to me), the sound of the radiator heating system, a high flying plane and three types of bird… all through closed windows.  And this on a quiet early Saturday morning.

The only film that I can say that captures what I live in is The Colour Of Paradise, a foreign film about a blind boy who in every way but the visual one, sees and lives much more than regularly sighted people. Everyone I know who has seen it, loves it and usually cries at it.  For me, it captures the way I can with my ears.  Funnily enough, it is an Iranian film and in Farsi with English subtitles.  I often watch foreign films and forget to switch the subtitles on; I’m just so engrossed with the sounds and intonations of the languages.

Of course, I’d love to see as everyone else sees.   I really treasure a short scene in the rather forgettable Star Trek Insurrection movie.  The scene in question is from Insurrection. Captain Picard and his crew beam onto a planet where ageing is reversed as is any physical impairment. Geordie, the engineer, finds out he can cast away his artificial and superior bionic eyes and the first thing he does is climb a hill to admire a sunrise. In the midst of a forgettable film is a little two-minute piece of magic.

Sunrise

From the first time I saw that scene to the most recent, I always think that scene is written for me. A piece of thoughtful beauty written and performed by people who can see like everyone else and probably long ago forgotten by everyone except for me. I would love to see a sunrise just like everybody else and that simple idea has never been shown in any other film I have seen though in fairness how many films even have characters where such a scene is possible?  I would do exactly like Geordie and climb that mountain to see the sunrise and the full moon and the full Vista or mist in a low-lying valley rather than the half-vista I get to see.    Maybe, though, the fact that I see over a hundred sun rises a year with just one good eye and appreciate every one of them makes me a just a bit more special than everybody else who don’t even notice them.   I like to think I’m a little bit like the little boy in The Colour Of Paradise who sees more than fully sighted people.

I also have never got lost in my life. I even ended up giving my Cairo taxi driver directions of how to get back to my hotel on the first day or my stay… a city with twice as many people as London and with no road signs.  Again I just see everything in my head or maybe I’m just part homing pigeon.

 

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About Stephen Liddell

I am a writer and traveller with a penchant for history and getting off the beaten track. With several books to my name including a #1 seller, I also write environmental, travel and history articles for magazines as well as freelance work. Recently I've appeared on BBC Radio and Bloomberg TV and am waiting on the filming of a ghost story on British TV. I run my own private UK tours company (Ye Olde England Tours) with small, private and totally customisable guided tours run by myself!
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One Response to How The Blind Can See With Sounds (& me too)

  1. Pingback: West Kennet Long Barrow – A 6,000 year old burial tomb | Stephen Liddell

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