Vital Data Carried with Electrical Currents
Everything we know about the world reaches us by means of our senses, without which we would be cut off from everything around us. Your senses let you obtain comprehensive information about what is happening in your body, as well as in the outside world. You can recognize a friend even you do not see her entire face or if you see her from behind. You can distinguish thousands of different smells and shades of color. You immediately feel a feather touching your skin, or hear the sound of a leaf falling, and you need make no effort to do so.
The parts of the sensory organs that collect information about the outside world are known as receptors. These convert the data reaching them into electrical currents to be transmitted to the brain via the nerve cells. The brain interprets these currents, thus letting you determine the properties of the object concerned. It then sends commands to other regions of your body, to take action in light of that information.
Some receptors in the ear react to sounds. Others ensure balance by reacting to the movements of the head. Receptors in the eye react to light and color, while receptors inside the nose react to chemical borne on the air. Receptors on our tongues react to liquids or foodstuffs dissolved in saliva. The receptors on our skin react to pressure, heat and pain. Receptors in our muscles and joints react when we move and provide information about the body’s position.
Our bodies are a marvel of design, but their sensitivity to the outside world and ability to react to what is going on is just as extraordinary. Not even the most advanced technological devices have the coordination necessary for the complex interactions between brain and body.
For example, computers have an encoding mechanism instead of sensory organs. This mechanism turns information into a series of electrical signals in binary code, which is analyzed by the computer’s processor, which serves as the computer’s brain. A smoke detector, for example, is designed in such a way as to react to rising heat and smoke particles. The detector turns these data into binary codes, which are then analyzed by the computer processor, and issues commands to the water sprinkler system to begin working. Although our perceptual systems resemble this, they possess ability far beyond merely analyzing automated commands. For example, when the brain perceives smoke, depending on the level of the smoke and its source, it can prompt you to open a window, use a fire extinguisher, evacuate everyone, or phone the fire department. This demonstrates that man’s creation goes far beyond that of any technical device.
How Electrical Signals Are CONVERTED into Sensations of Touch
Like all other sensations, feelings of touch form when the brain analyzes electrical signals transmitted from the skin cells. When you touch a piece of cloth, your brain perceives whether it is rough or soft, thick or thin. Receptor cells in your finger tips send information in the form of electrical signals, which the brain perceives as sensations of touch. For example, when you touch a rough surface, you can never know if it is really rough, because you can never make direct contact with a rough surface. All you know about its surface consists of your brain analyzing specific stimuli.
Millions of receptors of various sensitivities in the skin react to heat, cold, touch, pain, pressure and motion. These receptors send electrical signals to the brain and by means of these signals, we obtain information about the object we touch.
This book you are holding, together with all its details, is recreated in your brain. There is a physical book in the outside world, but one you are interacting with consists of a copy in your brain. The sensations of touching the book are entirely the analysis of electrical signals. Therefore, you are actually turning the pages and feeling the texture of the book in your brain. You can never touch the original book.
The wisdom behind sensitivity levels not being the same everywhere in the body
Blind people can read the Braille alphabet with their fingertips, but not with their knuckles or teeth, for instance. That is because the level of sensitivity in the fingertips is very much greater. There are some 640,000 sensitive skin receptors spread over the surface of the body.70
The density of these at the fingertips is 9,000 to the square inch, and they react in a millisecond to even the slightest friction. That lets us use our fingers for jobs requiring great sensitivity. Our elbows, however, are far less sensitive. There is considerable wisdom behind this: Were things the other way around, it would be exceedingly uncomfortable to rest your elbows anywhere, since they would feel the slightest roughness. And you would have to use your elbows to feel the roughness or smoothness of any surface. The body is specially created to fulfill all our needs, to be easy to use.
The wisdom behind touch receptors adapting to CONSTANT stimuli
Touch receptors react to sudden changes, but soon adapt to fixed stimuli. The brain is informed about the beginning of a contact and its end, but there is not such a heavy flow of information about the contact in between. There is great wisdom in this, because generally we do not need to be constantly informed about whatever may be touching our skin. It is sufficient that the touch receptors transmit information only when there is a change, which makes our lives very much easier. The ability of touch receptors to adapt quickly to constant stimuli is an important advantage of the nervous system.71
For example, when you put on your clothes in the morning, various receptors initially send your brain information concerning their weight, softness and pressure. But soon afterwards, these messages decrease and eventually cease, because, as already seen, receptors stop “reporting” constant stimuli at the same level of intensity. In the same way, when we first strap on a watch, we feel the coolness of the metal, the thickness and weight of the strap, but then we soon forget these details. However, if the strap loosens and is about to fall off, this attracts our attention. In the same way, receptors in our scalp immediately perceive the change when we take off our hats off, but our sensations soon adapt to the hat’s removal.
Feeling our clothes and accessories we wear at every moment would give rise to considerable discomfort. Therefore, the way that our skin adapts to fixed stimuli is of enormous importance—and a great blessing from our Lord.
The wisdom behind sensations of pain
Pain is a warning that a part of the body has undergone damage. Several million of our nerve receptors perceive pain, and the greater the shock they receive, the more they are stimulated. For example, when you hit our knee against a table or tread on a fragment of glass, the receptor cells in our skin react to something that is going to harm you. They send an urgent message to the brain, and you immediately take steps to escape that discomfort.
Some painful sensations take the form of aches, or of stings, or of burning. The sensation feeling of being stabbed reaches the brain fastest—at 30 meters (98 feet) per second. Receptors that perceive this are located on the outer layer of skin. Burning sensations reach the brain a bit more slowly, at a speed of 2 meters (6.5 feet) per second.
Behind the different speeds at which these sensations are perceived, there is great wisdom. For example, the way that we first experience a bee sting, followed by the gradual arising of a burning sensation, is of great importance. The stabbing feeling ensures rapid protection against the threat. No doubt that this is one of the examples of our Lord’s most wise creation.
The wisdom behind the feeling of pain decreasing during injury
Some people experience no pain when they are first injured and for a while afterwards. Even though injured, these people can run away from the danger or protect themselves. Sensations of pain are transmitted by nerve cells, which contain a substance called “endorphin”, which eliminates feelings of pain, aching and distress and relaxes the body.
Endorphin is literally a painkiller manufactured in the brain, secreted at the time the pain is felt. Its effect wears off as soon as the initial crisis has been overcome. In this way, even very serious injuries do not cause violent pain sensations for a certain length of time. Painkilling drugs function the same way. They do not actually treat most illnesses or injuries, but are merely chemical substances that prevent us feeling pain. The decrease in sensations of pain after an injury is another example of Allah’s mercy on human beings.
The Transformation of Light Energy into Sight Perception
The phenomenon of sight takes place gradually. Light particles (photons) pass through the lens in front of the eye, are refracted, and fall onto the retina at the rear of the eye as a reversed image. There, visual stimuli are transformed into electrical signals and transmitted by the optic nerves to a very small region in the rear part of the brain, known as the visual center. After undergoing a series of processes, this electrical signal is perceived in the brain as a visual image.
The two kinds of receptor cells in the eye are known as cone and rod cells. Rods are so sensitive to light that they enable one to see even under a pale light. However, in strong normal daylight, they become unable to transmit any signal. Cones, on the other hand, function in intense bright conditions and enable images to be perceived in broad daylight.
When you look at a television screen, for instance, your optic nerve consisting of 1 million nerve fibers transmits information from your eye to the brain.72 The stimulation of light from the screen causes a chemical chain reaction in the retina’s light receptors. As a result, the signals from the retina stimulate the optic nerves, which in turn stimulate the brain.
Signals sent from the brain travel at a speed of 100 meters (328 feet) per second and stimulate the muscles controlling the toes, ankles, legs, shoulders, arms, wrists and fingers. With the perception of an image, reactions such as heading towards one’s chair or pressing the remote control soon follow.
The human eye perceives various colors, ranging from red to mauve. It cannot perceive frequencies that lie outside this range, such as infrared or ultraviolet. This is, again, a very wise precaution. If our eyes were arranged to perceive lower frequencies of light waves instead of that specific range, then we would end up perceiving blurred images like those on a radar screen. If our eyes were arranged to perceive higher wavelengths, then we would perceive images rather like x-rays. Through the mercy of Allah, however, the cells in the eye transform only light waves within those dimensions into electrical signals, and thus allow us to see such colorful and detailed images.
The Three-Dimensional World That Forms in the Brain
The brain is exceedingly adept at determining the distance of objects. Both eyes act in tandem and register images seen from different angles. The difference of angle between the two images helps the brain calculate the distance of the perceived object. The two images transmitted to the brain are compared and the distance of the object determined.
That is why you perceive this book as a three-dimensional image. Were it not for that ability, we would see everything double and in a single plane. And so, the fields of vision of the two eyes being at different angles is a very wise result of creation.
Let us imagine that you are watching a tennis match. One of the players easily returns a shot from over the net. Your brain forms an opinion of what the shot is like. The light illuminating the ball, net and racket all reach your eyes simultaneously, without your being aware of it. Yet what you perceive as a racket or a tennis ball is an image resulting from collaboration between your brain and a number of electrical signals, each directed towards the relevant region of the brain. However, there is no clue in your brain that you are watching this tennis match. Scientists can describe how the data regarding sight, sound or scent is transmitted toward the relevant parts of the brain. But what really surprises them is how these electrical signals are reconstituted within the brain back to their original form.
Gerald L. Schroeder describes a few of the miraculous aspects of the phenomenon of sight:
The process of biological information transfer is a tale of awe. Consider just one aspect of this bodily train of events. How does the brain decide that the two-dimensional image protected onto the eyes’ retinas represents a three-dimensional world? After all, the visual image is converted into an array of electrical stimuli, each of which is a one dimensional pulse of voltage . . . From where does it get its smarts?73
As Schroeder emphasizes, the way that electrical impulses carry encoded information, and how they are then interpreted as practically identical to their counterparts in the material world, is the product of a superior Intellect. The mind that Schroeder refers to belongs to our Lord, Who created us all and gave us eyes with which to see. This fact is revealed in the Qur’an:
Say: “Who provides for you out of heaven and Earth? Who controls hearing and sight? Who brings forth the living from the dead and the dead from the living? Who directs the whole affair?” They will say, “Allah.” Say, “So will you not guard against evil?” That is Allah, your Lord, the Truth, and what is there after truth except misguidance? So how have you been distracted? (Surah Yunus: 31-32)
The Transformation of Scent Molecules into Electrical SignalS
How the sense of smell works is similar to that of our other senses. That part of the nose that can be seen from the outside merely takes in scent molecules in the air. Flying molecules from a rose or a spoonful of vanilla come to receptors on vibrating micro-hairs in the region of the nose known as the epithelium, where they set up a reaction that reaches the brain in the form of electrical signals, which our brain then perceives as smells.
There are astonishing systems in the transformation of the effect caused by scent molecules into electrical energy. In the sensitive membrane inside the nose are some 50 million nerve cells, each of which contains a large number of proteins. A scent molecule can attach to one of the protein molecules in these nerve cells for as long as its form dictates. An electrical polarization thus results in this region, which gives rise to electrical signals that reach the scent perception region immediately beneath the forehead. Here the information from the different cells is analyzed, and the source of the scent is determined when they are sent to various brain structures. (For details, see Harun Yahya, The Miracles of Smell and Taste.)
You are indebted to the sensitive structure in your nose for your ability to enjoy the smells of newly baked bread, the roses in the garden, new-mown grass, soil after rain, hot soup, strawberries, parsley, the soap you use or shampoo. Most people never stop to think about how many scents they detect each day and how an image of their origin forms in the mind, thanks to these scents. Yet your sense of smell is one of the most important factors in your ability to recognize foods and beverages.
Smells from the environment enter your nose with every breath you take. The human nose has a very impressive ability to analyze a smell it detects within 30 seconds and to distinguish between 3,000 different aromas.74
Electrical Signals PERCEIVED as Tastes
Our sense of taste analyzes proteins, ions, complex molecules and a great many other chemical compounds, working non-stop on our behalf right through our lives. The tongue functions just like a laboratory, analyzing different chemical compounds. Every food we eat or drink consists of an enormous number of taste molecules. There are hundreds of thousands of separate chemical substances in every dish we eat. Taste receptors in the tongue analyze these different molecules with impeccable accuracy. (For details see, Harun Yahya, The Miracles of Smell and Taste.)
A special design allows this analysis to take place. There are specialized cells in the tongue, the first phase of the digestion process, that are found nowhere else in the body. These cells analyze foodstuffs and transmit data regarding them to the brain in the form of electrical signals, which the brain again interprets as flavors.
The way that the tongue’s taste-perceiving cells in the system are in just the right place, numbers and form is an example of their superior creation. The way that the brain, which interprets the electrical signals, tells us what we are eating, distinguishes what we are eating on every occasion, and tells us whether they are bitter, sweet or sour by analyzing chemicals is one of the miracles of creation in our bodies.
Perception of Electrical Signals as Sound
The outer ear collects sounds from the outer world and forwards them to the middle ear, which reinforces the sound vibrations reaching it and transmits them to the inner ear. The inner ear then sends them to the brain by turning them into electrical signals according to their intensity and frequency. After visiting several places in the brain, the messages are finally transmitted to the hearing center where these signals are processed and interpreted, and the process of hearing finally takes place.
One of the most surprising things is the speed at which the 20,000 micro-hairs in the channels in the ear react. The middle channel vibrates at 256 times a second. The channel immediately above it vibrates at 512 times a second, and the channel above that, at 1,024 times. The micro-hairs’ efficiency in analyzing such fast vibrations allows us to distinguish with great sensitivity among musical notes. This constitutes one of the most sensitive and rapid reactions in the body.
As the brain resolves the sound vibrations of speech reaching it, it must convert the sound into syllables, and then into sentences, without being affected by the speaker’s speed, tone or accent. We are generally completely unaware of this amazing analytical system inside our heads. The ear’s complex design has frequently been the subject of praise from scientists.
Of all the organs of the body, few can accomplish as much in so little a space as the ear. If an engineer could duplicate its functions, he would have to compress into approximately one cubic inch a sound system that includes an impedance matcher, a wide range mechanical analyzer, a mobile relay and amplification unit, a multi channel transducer to convert mechanical energy to electrical energy, a system to maintain a delicate hydraulic balance and an internal two-way communication system. Even if he could perform this miracle of miniaturization, he would be unable to match the ear's performance. It can set itself to hear the low throb of a foghorn at one end of its range and the piercing wail of a jet engine at the other end. It can make the fine distinction between the music played by the violin and the viola sections of a symphony orchestra. . . . Even during sleep the ear functions with incredible efficiency. Because the brain can interpret and select signals passed to it by the ear, a man can sleep soundly through noisy traffic and the blaring of a neighbor's television set and then awaken promptly at the gentle urging of a chime alarm clock.75
The ear also performs selective perception. Consider what happens when you hear the sound of a child crying at night. The sound is sent to the relevant region of the brain and gradually deciphered there. What kind of sound it is, and whom it belongs to is determined. Since you have a long-term memory, this sound seems familiar and you realize that it belongs to one of your children. With this information your brain now knows that your child wants help, and carries out preparatory measures such as the release of adrenaline in order to set your body in motion. All this encourages you to head directly for your child’s bed. In addition, your memory tells you where your child’s bed is. This perception and chain of events, here described in very simple terms, actually involve miraculous biochemical and bio-electrical processes, taking place as the result of hundreds of thousands of axons, each with thousands of terminals, establishing a connection with a quadrillion (1,000,000,000,000,000) fibers. You never realize that the brain is deciphering the signals. So how can it be structures of tissue that perceive all this? This question encourages unbiased scientists to reflect upon.
Gerald L. Schroeder, Professor of Nuclear Physics at the Massachusetts Institute of Technology one of these scientists, questions the following about the sense of hearing:
And then comes the hard part of the hard question: the sound of music . . . become[s] converted to bioelectrical pulses that are chemically stored in the cortex of my brain. But how do I hear the sound?. . .But I don’t hear biochemistry. I hear sound. Where is the sound generated in my head? Or the vision; or the smell? Where is the consciousness? Just which of those formerly inert atoms of carbon, hydrogen, nitrogen, oxygen, and on and on, in my head have become so clever that they can produce a thought or reconstitute an image. How those stored biochemical data points are recalled and replayed into sentience remains as enigmatic mystery.76
Schroeder’s use of the term “mystery” is inaccurate. Of course it is not the brain that perceives the outside world, but the Soul given to man by Allah. The human mind is not a result of biochemical processes, but a blessing bestowed on Man by Allah. In one verse our Lord states:
Then [He] formed him and breathed His Spirit into him and gave you hearing, sight and hearts. What little thanks you show! (Surat as-Sajda: 9)
Balance and Movement
How do you manage to stand upright, despite the constant tug of gravity? How can you suddenly turn around without falling over?
Organs at the entrance to the inner ear assist with balance by sending information to the brain about the movement and position of the head. Head movement causes the liquid in the channels to move and the micro-hairs to bend, which initiates messages that go directly to the brain. However, the tissues in this channel react differently to different movements. One is very sensitive to up and down movement, another to movements to either side, and another to forward-bending movements.
In the inner ear there is a special mechanism, known as the vestibular system that helps us keep our balance and reports which direction we are moving in. The vestibular system consists of three tunnels or semicircular channels and filled with a special fluid. Each channel has a region covered in hairs—receptor cells. And when we move, the liquid in the channels flows over the hairs and bends them. This bending is converted into electrical signals that are sent to the brain, which then decodes them to tell us what position we are in.
The reason why we sometimes lose our balance is a shock experienced in the inner ear. When you bend your head or turn it from right to left, the hairs begin to lean over, and this causes them to move in a very small fraction of a second in relation to the movement of the head and muscles. As these hairs move, chemical reactions that take place in the nerves at the base of every hair produce electrochemical signals that transfer information to the brain. Subsequently, it combines these signals—indicating the angle of the joints and contractions in the muscles—to analyze movement in the body.
This system in the ear works together with receptors in the eyes, neck, muscles and tendons. On its own, none of these is sufficient for a person to remain on balance. When you look out the window of a stationary train and see another train pulling out, your eyes will provide information as if you were actually moving. However, other nerve receptors in your body will report just the opposite and let you perceive your surroundings correctly. In this way, you realize that you are standing still and the other train is in motion.
Of course the process of the brain putting these data together actually takes place thanks to the flawless communication transmission of more than a billion axons. Our bodies’ equilibrium is the product of a conscious creation, as revealed in the Qur’an:
The kingdom of the heavens and Earth belongs to Allah. Allah has power over all things. (Surah Al ‘Imran: 189)
Similar Signals Carry Very Different Messages
The common feature in our sense organs all turn the electrical stimuli reaching them into electrical signals and forward them to the relevant sense centers in the brain. At this point, we find a most surprising fact: All of the messages the brain received from the sense organs consist of the same kind of signal. All the stimuli transmitted to various centers in the brain are in the form of electrical currents, yet these identical currents contain very different information and cause different effects in the different centers of the brain—which is most astonishing.
In her book The Human Brain, Susan Greenfield draws attention to this extraordinary situation:
Another tantalizing and related mystery of the brain is why electrical signals arriving the visual cortex should be experienced as vision, while exactly the same kind of electrical signals, arriving in another part of the brain such as the somatosensory cortex or the auditory cortex, should be perceived as touch and hearing respectively.77
The truth that Greenfield describes as a “mystery” is quite obvious: The functions of our sense organs were brought into being with a flawless creation, just like all the other systems of our bodies. Our Lord has arranged matters in the same way that He produces plants and fruits with very different tastes, colors and smells from the same black soil, He has also ensured that identical signals are perceived in totally different ways in our brains, making us able to perceive the colors, scents and tastes in the outside world.
Conclusion: The Perceptual World Created in Our Minds
The subject matter of this chapter, the way the signals collected by our sense organs are perceived in the brain, shows us another important fact: we can never have direct contact with the outside world itself. There is matter outside us, whether we see it or not. But we can never make direct contact with it. The world we have direct experience of consists of interpretations of electrical signals in our brains. (For detailed information, see Harun Yahya, The Other Name of the Illusion: Matter, Istanbul: Kultur Publishers, 2002, Harun Yahya, Idealism: The Philosophy of the Matrix,and The True Nature of Matter, Maryland: Khatoons Inc., 2003)
As mentioned earlier, what you perceive as the outside world is merely an effect in your brain created by electrical signals. The blue of the sky you see from your window, the softness of the chair you sit in, the aroma of the coffee you drink, the tastes of the food you eat, the sound of the telephone ringing, your nearest and dearest, and even your own body are all interpretations of electrical signals in the brain. Professor of Nuclear Physics Gerald L. Schroeder, refers to this in these terms:
...Wiggle your toes. Feel them? But where do you feel them? But where do you feel them? Not in your toes. Toes feel nothing. You feel them in your brain. Anyone who has had the misfortune of having. . . . The brain has within it maps if the body that record every sensation and then project that sensation onto the mental image of the relevant body part. But it certainly feels like I’m feeling my toes in my toes. And it is not just the toes. The entire reality, what we see and what we feel, what we smell and what we hear, is mapped in the brain and then those recorded out to out consciousness from within the two-to-four millimeter (about one-eight inch) thin wrinkled gray layer, the cerebral cortex, that rests at the top of each of our brains. There is a reality out there in the world, but what we experience—every touch and every sound, every sight, smell and taste—arises in our heads. All our mental images, fantasy or factual, are built on our life’s experience.78
The conclusion we arrive at is a scientifically proven fact. For anyone to believe, in the face of all the evidence, that he or she can have actual direct experience of the outside world is rather like believing that the characters in a television program are real.
So where does this fact about the essence of matter lead us?
Who is it who, in a tiny space and without the need for an eye, retina, lens, optic nerves or pupil, perceives electrical signals as a bright garden, and takes pleasure from that?
Who is it who, in a brain which no sound enters, perceives electrical signals as a delightful melody?
Who is it who, without the need for hands, fingers or muscles, perceives electrical signals in the brain as the softness of velvet?
Who is it who experiences sensations such as hot, cold, texture, form, depth and length as identical to their originals?
Who is it who, in the brain which no smells enter, distinguishes the scents of many different flowers, or who becomes hungry on smelling a favorite food?
To whom does the consciousness that will interpret all you see and feel belong? And who is the conscious entity who watches all these images, reflects, draws conclusions and makes decisions?
Clearly, it cannot be a brain consisting of water, fat and proteins, made up of unconscious molecules perceiving all these. Every rational person of good conscience will immediately grasp the existence of an entity or soul that watches all the events throughout the course of one’s life on the screen within his brain. Every human possesses a soul capable of seeing without eyes, hearing without ears, and thinking without the need for a brain. It is Almighty Allah Who created the world of perceptions of which the soul has direct experience and Who continues to create at every moment.
In one verse it is revealed that:
Clear insights have come to you from your Lord. Whoever sees clearly, does so to his own benefit. Whoever is blind, it is to his own detriment. (Surat al-An’am: 104)