Chapter 3     How We See and Hear

In the last Chapter we gained some experience of what it means to have a blind spot - a small area that each eye cannot see - and how easily our brain fills in this blank for us. Extending this to our whole process of knowing the point is that we don’t know what it is we don’t know because our mind draws together what we do know into a coherent whole that will serve our purposes for the present time. We tend to enjoy a rather blissful form of blindness until something happens that doesn’t seem to fit with our story of how we are situated and how things should be. It takes a disturbance of some sort to remind us that there may be a lot of things we don’t know. This awareness of the possibility of blind spots is a useful and powerful attribute that our minds tend to develop as we gain more experience and maturity as human beings.

In this book it is my wish to try to expose some conceptual blind spots that I think have developed in all of us due to our habitual ways of living together and upon which the new ideas in mind-body science can shed some light. Another subtitle I could have used for this work is: Seven Things that Most People Don’t Know about Knowing. These seven kinds of blind spot relate to seven different aspects of knowing that I will unpack in some detail as we go along.

Seeing and hearing are different connectors

In this Chapter we will go more deeply into the process of visual perception – how we use our eyes and brain for seeing – and also start thinking about the wonderfully different business of our hearing. Seeing and hearing are very different senses so they play different roles even though our entire sensory apparatus is designed to work together, of course.

The physical medium that we use for seeing is light - the unbelievably fast-moving light ray (or electromagnetic radiation) that travels through space, even totally empty space, at about 300 million metres/second. We normally think of it as travelling in straight lines unless passing though a transparent material such as a glass prism and it can be blocked by any opaque material. The substance of hearing is the slow-moving vibration that we call sound. Like most waves, this requires an elastic material (air, water, etc) to pass through to produce a series of minute pressure fluctuations. Unlike light, sound can travel through walls and around corners to a certain extent, but only at about 350 metres/second in air or some 1500 metres/second in sea water, for example; its speed varies according to the medium that carries it. The sound waves spread out like ripples on a pond to form a field, which can interact with other fields and be reflected or altered, e.g. by resonance. You can think of sound as a form of motion that is known as wave propagation, meaning that something is conveyed from one place to another, but the air itself does not go there; it just goes up and down.

These sound waves can be felt by many parts of our body, but it is the ear that is especially designed to deal with them. They are channeled by the outer ear onto your ear drum, which is sensitive to pressure fluctuations. Inside it is an amplifying mechanism that makes the vibrations even clearer and then a fluid filled chamber through which they travel even more sweetly to reach sensory nerve endings that are thousands of tiny little hairs from which a trunk of nerves goes directly to the brain. It is an amazing organ indeed! In the eye there is an adjustable lens enabling us to focus clearly on the light rays reflecting from of a particular object. Where this light meets the lining at the back of the eye (the retina) there are two types of specialised receptor cells that discern its properties and where it has been reflected from and connect via the optic nerve directly with the back of the brain. The image created by these cells would be upside down and back to front, but our brain has no difficulty coping with that. Our two eyes side by side provide a stereoscopic view making it easier to judge distance and depth of field, but the width of our visual field is more limited than many animals meaning that we have to turn our head to see behind our back.

We live in a world where vision is the predominant sense. Visual perception is often described as the most significant perception channel, meaning that it is where we get 75% or more of all the information we need (using the ‘old school’ information processing model of cognition). People who are blind, of course, have to substitute other senses to try to achieve the same result and there are some remarkable examples of how this can be done.  Helen Keller, who was both deaf and blind, could know an extraordinary amount about people and places from her unusually keen sense of smell and her sensitive hands.  I mentioned earlier the way in which a touch connection, using a stick, can help blind people locate parts of their world that are close by. Deaf people have developed the most wonderful ways of talking to one another, as you know. I attended a funeral service for a deaf person recently and I found that a church full of deaf and mute people making meaning together is a truly memorable and moving experience.

For most of us, in our quest for meaning, there is something primary about seeing. We tend to say “I see” to denote our understanding of something. Whenever we feel the need to know something our first impulse seems to be to look for it rather than to listen for it or smell or taste or touch it, all of which may happen a little later. In art we give prominence to the visual arts in the form of paintings, theatre, cinema, etc. Yet there seems to be a rather special place for hearing, too, and it has to do with music. One pointer to the importance of music is the evidence that it has been around as long as we have, perhaps even longer because some hominid species that preceded us are believed to have sung and made music; more of this later. Though it takes many different forms, music seems to touch all humans in some way. The way it does so is very revealing, I think, of some special features of the human mind so we will explore this further.

What seeing and hearing (and all our senses) have in common is that they create a connection between our central nervous system and everything around us. When you hear something you become aware of its existence and you may choose to give it your attention for a period of time or you may choose to ignore it after a while. When you see something you notice it and say there it is. You may watch it for a while or you may look elsewhere and see it only in your peripheral vision or not at all. This is a kind of mental connection that you make with the object in question. In the ‘old school’ information processing paradigm this would be described as the receiving of information into the brain via the eyes and ears – essentially a passive process and largely one-way - even though it would be acknowledged that previous experience could modify the information as it arrived. I hope that the experiments on offer for you in this Chapter will help to explain why I think it is more useful to think of perception as a thoroughly two-way connection.

If you imagine you are sitting in the same room with me at this moment, what are our principal means of connecting? It is most likely we will be looking towards each other. Fairly recent brain research has shown that a huge amount of the activity within our brain is directed towards facial recognition. This brain activity is seemingly out of proportion compared to other aspects of seeing indicating that the making of our story requires us to put the facial identification of others ahead of almost anything else. Even though we are not looking directly at one another most of the time, we are using our sight to connect with one another and with our surroundings as we work or play together in this room. We are also using our hearing, of course, and other senses. Those of us with impaired hearing or sight will be relying a little more on one of the other means of being in touch with what is happening; we are all striving to maintain an effective connection with whatever is most important to us and to our story at that time.

Our story exists in our imagination in the form of a constant stream of patterns or images only some of which seem to have words attached. What a wonderful aspect of our mind is the realm of the imagination! Human existence is made rich and interesting and wonderfully satisfying and also difficult and painful at times by the power of our imagination – by the fact that we live with our story in the playground of our imagination. These images and shapes are constructs of our mind, made up within our brain from patterns previously encountered, which don’t necessarily bear any relation to what we are looking at or hearing right now. I can look at my wife or my grandchild when I am with them and I can also see them now, if I want to, in my imagination. To my brain it is basically the same process. It has been found that, to a large extent, the same parts of my brain light up when I imagine my child’s face as when I look at my child’s face. If I should have an amorous thought regarding my absent lover (i.e. wife, I should add), my brain would be behaving almost as if she was right there in front of me.  In both cases it is a particular pattern in my brain, also known as a neural net, which has become associated with that state of mind. Surprising as it may seem, our brain is not designed to immediately tell the difference between what is real and what is imaginary.

Illusion and perception are the same process

Consider the simple visual illusions below. There is actually no white line triangle, but it looks as if there is in the illusion called the Kanizsa Triangle. There are just three black line shapes which seem to make an incomplete black line triangle and bits cut out of the circles which together suggest another triangle. Your brain is using its powers of imagination and preexisting patterns – it knows about triangles – to create shapes that are not really there? In the Ponzo illusion, is one horizontal line longer than the other? You suspect it’s an illusion, but you have to check it out to be sure that they are exactly the same length. Like the blind spot experience we had earlier this is a reminder that the mind can tell us things that are not really true.

                                                                                                                         

Figure 4. Kanizsa Triangle (left) and Ponzo Illusion (right).

Here is another example of an illusory visual experience. Have you ever been sitting in a train at the station when the train next to you pulls out in the other direction and you could swear for a moment that it was your train that was moving? The perception is as real as if you were moving, but by checking yourself against some other markers, on the station perhaps, you can soon determine that it was not real. You do this after the event. Your brain could not determine the reality of the situation in the act of perception. It has to make a subsequent reference to another source. This throws some uncertainty into the belief that we will know what is real just by looking at it.

One can easily think of illusions affecting our auditory system, too. Making the sound that resembles a fart (and for some strange reason is known as a raspberry) is a universally favourite trick in the minds of children. The radio sound effects technician has a huge array of noises and sounds that will represent a very clear image in our minds, although the sound may be only an imitation of the real thing.

Look at the page below with the dark blobs on it until you can see a clear picture of something. This picture has appeared in many books, but usually without acknowledgement to Henri Bortoft and his very first monograph entitled Goethe’s Scientific Consciousness. It was actually created by his wife, Jackie Bortoft, and I use it with their permission.

 

Figure 5. What do you see in this picture?

The organising idea

The question we are considering now is: what is it that made a jumble of dark blobs on the preceding page turn into a meaningful picture? You might have needed a clue that it is the head of a tall animal commonly seen in a zoo. Once you see it there is not the slightest doubt what it is. The blobs themselves did not change so it must be something performed by your brain or your mind. It is an extension of what we have experienced before with the line through the blind spot and the triangle illusion and so on. It can be explained by the fact that your brain has a pre-existing pattern or image that it uses to make meaning – to make sense of what you are looking at. Henri Bortoft, whose most recent book is The Wholeness of Nature, called this the organising idea. He wrote in exquisite detail about the difference between the empirical explanation that the giraffe is already on the page and the biological explanation that the giraffe arises from the way of seeing it – in other words seeing is an active, not a passive process. We will go further into this in the next Chapter.

You may also like to explore the well-known ambiguous figures in Figure 6 at the end of this Chapter. The switching of your mind from one figure to the other occurs more easily for some people than others and more easily with some figures. This does not have any practical significance for the everyday working of your mind.

For the time being I will leave you with the thought that our process of visual perception involves a two-way connection between our brain and the objects we are seeing. As well as the sensory (or receptor) nerve fibres that enable light rays reaching the eye to also reach the brain there are motor (or effector) nerve fibres that control the operation of the eye and the perception process in such a way that they shape what it is that the eye detects. Thus the brain can control where we put our attention, what we focus on, which light rays are to be given emphasis and therefore what we see. The business of where we put our attention will occupy our minds in the next Chapter. We do not see everything that is out there to see, of course. We see what our brain wants us to see – what it knows. Henry David Thoreau put it beautifully when he said: It's not what you look at that matters, it's what you see.” The inimitable Mark Twain must be allowed to add: “You can't depend on your eyes when your imagination is out of focus.”

Images of sound

The process is essentially the same for hearing. As with sight, auditory perception involves an active input from our brain that plays a large part in determining what we actually hear. It’s the same kind of two-way connection. We don’t necessarily hear what is there; we hear what we think is there because we’ve heard it before and we know about it from our history. At the same time hearing is also very different from seeing. It has a more subtle, but very profound role in the working of our mind. It is no less active, but it is less intrusive and less probing than seeing. There is a saying attributed to Lorenz Oken to the effect that sight takes you into the world whereas hearing brings the world into you. At the important interface between knowing and not knowing perhaps we can learn something from hearing that would not be obvious were we relying only on the visual sense.

Try listening to Tibetan temple bells or a ‘singing bowl’ in the distance until the exact time the sound disappears. The sound is obviously out here in the air, but it is also inside us when our mind makes that connection. What is it we are hearing? Basically we are hearing tones and overtones, which are subsidiary sounds at higher frequency. What is the meaning of tones? With visual images we see what we called pictures – patterns of light that immediately mean something (like giraffe) - but they are basically just patterns in space - and also in time if the image is moving. Tonal images also tell us about time and space in a much more subtle way, which can be approached by considering how we make music and the experience of listening to music.

The perception of music

Tones are physical events occurring in the external world as wave patterns, but the extraordinary thing about them is that they also exist in our imaginal world as distinct patterns of sound. A sequence of tones that forms a melody is more than just a collection of sounds when perceived by a listener who is not entirely naive to that music (in other words, who knows it). A melody has a flow of meaning which is very like the meaning of a story. From the beginning it appears to be heading somewhere, may emphasise certain matters along the way, often builds to a climax and usually resolves itself in a satisfying manner such that the listener knows the end has been reached. This dynamic quality of melody, which is of the relations between the tones rather than the individual tones, gives music its sense of time; it is a flowing pattern - a kind of moving image. Someone familiar with musical scales and cadence can describe this in terms of relationships between phrases and between certain intervals on the musical scale in any particular key, e.g. the seventh or leading note has the effect of leaning strongly towards a return to the tonic or base note (the first or eighth tone) if you listen carefully.

Several notes sounding together constitute a chord, which evokes the spatial component of the imagery of tones. Different chords may be experienced by the listener as very different sensations or feelings, e.g. a major chord compared to a minor chord, the latter being more constrained, melancholy or even fearful. Composers use the structure of chords to enrich the meaning of their music in a way that corresponds to an artist’s use of space. It is not the same conception of space as we are used to, but I agree with Victor Zuckerkandl, who explained these ideas in much more detail, that is an aspect of our imagination that invites a deeper appreciation of the workings of our mind.

Music may also help us to understand the elusive concept of wholeness, which lurks just under the surface of all our thinking about mind-body science. The individual notes in a fine piece of music need one another, of course, to become a meaningful whole just as the blobs on the page needed one another to make a giraffe. Consider the apparent simplicity of the following passage of music, which is mostly one type of note (crotchets), uses only a few lines of the staff and can easily be played by even such an amateur musician as me. When you hear it your imagination may be filled as mine is with the sound of an orchestra and choir in full voice – if you recognise the tune – because it is one of the most powerful melodic themes in the history of the western world. What is most remarkable is that Beethoven was almost totally deaf when he composed this for his last Symphony. These tones, arranged like this, came from his imagination and they come to life in our imagination when we make a connection through the images of sound.

Figure 6. The theme melody (Ode to Joy) from Beethoven’s Choral Symphony (No 9).

The perception of music will be considered in more depth later because I believe it has a special place in any study of the human mind. The great violinist, Yehudi Menuhin, wrote: “the magic of listening brings us closer to the central core of the universe. To begin to comprehend the mystery of life it is not sufficient to touch and to see – we need to hear, to listen, and thus to unite heart and mind and soul.” His life-long friend, Ravi Shankar, also said: “the highest aim of music is to reveal the essence of the universe it reflects.” Music brings enormous enjoyment to human beings especially as it becomes familiar and our imagination starts to anticipate and remember its flow – the shape of its imagery. Pop music and rock concerts send young people into a frenzy, certain moments in opera bring explosions of applause and shouting (bravo!), advertising jingles oil the wheels of commerce and the slow movement of a piano concerto, for example, can bring rapture for many of us. Despite its mystery we cannot ignore music as an aspect of our special human mind.

Sound biology

Many people are concerned that humans are becomingly increasingly deaf – not just industrial deafness from so many machines or the deafness of young people from too much loud music - but a profound lack of attention to all the small sounds around us. This manifests itself in a kind of insensitivity to the degradation of our physical world and the cries for help of our fellow human beings. We are bombarded with visual images of starving children and bomb-ravaged streets, but at the same time it seems that no one is listening.

The biology of sound is a subject we can only touch on briefly here. The human voice is a truly amazing vibration and it reveals so much about our being that we are keenly attuned to changes in our own and other people’s voices. It is such a complex blend of frequencies and resonances that even the best digital technology has not yet been able to synthesize it exactly. There are many schools and programs of voice work that are designed to heal, enrich and liberate the human mind and body. Chris James’ Discover Your Natural Voice and Jill Purce’s The Healing Voice are just two well-known examples. The Tomatis Method uses voice and hearing for psychotherapy and to overcome learning difficulties in children. A “life of transformation through listening” is described in the book by Alfred Tomatis, The Conscious Ear.

Both seeing and hearing are vital functions of our mind and there is more to it than meets the eye – or the ear. In the next Chapter we will study visual and auditory perception in more depth, consider the important issue of attention and discuss some of the broader implications of the sensory loop that enables the human mind to work in the way that it does.

 

4,000 words

 

                                                                       

 

Figure 7. Some well-known ambiguous figures (from top left: Eskimo or Indian chief; old man or young man; vase or faces; old woman or young girl; duck or rabbit).