Which of these two shapes below, in your opinion, is called “bouba” and which “kiki”?
Those who think that the shape on the right is called “bouba” and the one on the left “kiki” are not alone. Nine of every 10 people think the same thing. The phenomenon, discovered by German psychologist Wolfgang Köhler, has been investigated for nearly 100 years but still isn’t fully understood. What’s the connection between shape and sound?
One of the conventional explanations for the phenomenon is that when we say “bouba,” our mouth makes a more circular motion than when we utter “kiki.” In other words, the intuitive coordination between shape and sound stems from the system of connections in the brain between the part that senses the movement of the mouth and the tongue – and the visual part, which sees the shapes. From the perspective of Amir Amedi, this is a simple illustration of a far more complex phenomenon that he’s been investigating from multiple aspects throughout his career: the deep, mysterious and ramified connection between the senses.
Prof. Amedi, who directs the Baruch Ivcher Institute for Brain, Cognition and Technology at the Interdisciplinary Center, Herzliya, is one of Israel’s leading brain scientists. The implications of his work are staggering. He has made it possible for the blind to see via sounds, and for the hearing-impaired to hear via their fingers. His laboratory is exploring how the hidden doors between the senses can be used to rehabilitate both people who, for example, were born blind or deaf, and people whose brains have been damaged by a stroke or an accident, while also looking for ways to heighten the abilities of healthy individuals.
For example, he and his staff are developing technologies that will make it possible for people who have difficulty concentrating to immerse themselves in meditation and enjoy its immense psychological benefits. On a routine day, Amedi’s laboratory is hard at work attempting to harness the existing senses to the creation of super-senses – such as seeing heat like a bee and being able to discern objects behind a curtain like Superman.
These days, Amedi has an additional goal, perhaps even more ambitious: to identify the places where body and mind intersect in the brain. Most of his efforts in this regard have not yet been published; they are, he avers, “significant leads” toward solving a problem that has occupied humanity from time immemorial.
Amedi has published perhaps 100 articles on diverse issues of brain research, but he is most identified with the development of “EyeMusic,” a tool for the blind that provides visual information through an auditory musical experience. In the past few years the system has been greatly improved, so that now a sightless person who is proficient in its use can “hear” an image of 1,500 pixels in one second of music. Amedi notes with pride that this resolution even makes it possible to identify an individual human face. In his laboratory he has succeeded in having blind people make use of the musical eye in order to perform complex tasks that necessitate identification of colors and motion in a three-dimensional space, such as choosing a red apple from a dish of green apples.
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One of the reasons Amedi has decided to be interviewed here extensively for the first time, is that he wants to free himself to some extent from the image of “the guy who makes it possible for the blind to see through the ears.” EyeMusic is an important tool, but no less important are the discoveries made in connection with it, both before and after, about the nature of the human brain.
According to Amedi’s theory, the brain is built completely different from what was previously thought, the walls erected between the senses are artificial, much less stable and rigid than we imagined, and these elements can be used to plasticize brains that have apparently solidified completely. A broad survey that he published last summer with his colleague Dr. Bendetta Heimler in the journal Neuroscience and Biobehavioral Reviews sums up 20 years of research: “Brain plasticity spontaneously decreases with age… but it nonetheless can be reignited across the lifespan.”
The studies by Amedi and his colleagues are highly complex, multilayered and difficult to understand. On the other hand – and this is perhaps the most alluring and appealing element of his work – there is something intuitive and easily graspable about it, because it relates directly to the senses. Everyone has senses and everyone feels that they are all deeply interconnected. In a certain sense, Amedi and his colleagues are giving a name and a shape to what we all feel.
What this region does
Amedi, 47, is married to Inbal, a veterinarian and brain researcher, and the couple have two daughters, aged 10 and 7. He was born in the Kurdish Quarter of Jerusalem’s Nahlaot neighborhood, the eldest of three children. In his first years he lived with his parents and their siblings in a crowded house that his grandfather built with his own hands after reaching Israel by foot from Kurdistan. Afterward they moved across town to a transit camp and from there to the nearby Ir Ganim neighborhood, which he recalls fondly as “Jerusalem’s top crime neighborhood of the time.” His father was a bus driver, his mother was a homemaker, and the school Amir attended was rough and violent.
He has high praise for his parents: Despite their economic straits they never scrimped when it came to education. His life preserver was a program for gifted children which, beginning in the third grade, yanked him out of school for one day a week to broaden his horizons at the city’s nature museum.
“It was an amazing experience,” he recalls with a smile. “Studies there were very diverse, from mathematics to painting. It was a real amusement park of pure passion for knowledge in a very friendly atmosphere.” In seventh grade he was accepted to the prestigious Hebrew University Secondary School (aka Leyada), and after getting over the profound culture shock there (“They would correct my Hebrew”), he embarked on a sure path to academia following his army service.
The only question was what he would study. At just over 20, Amedi, an ardent saxophone player, was torn between the Academy of Music and the Hebrew University of Jerusalem’s biology department. In the end, he decided to study both subjects, during the day skittering between the buildings on the university’s Givat Ram campus and at nights working to earn money as a security guard at the nearby Israel Museum. During his undergraduate years he came across brain science by chance, in the wake of a young woman he was pursuing. His affinity for the field was revealed immediately: Within two weeks his plan to become a maritime biologist was scrapped, followed by his saxophone dreams.
After earning his bachelor’s degree, Amedi went directly into a doctoral program in neural computation. From the outset of his acquaintance with neuroscience, he felt that the field was suffering from unnatural divisions among the different areas of knowledge. Not only were various aspects of the brain studied by scientists from different disciplines – biology, psychology, medicine, linguistics – even neurobiologists, who focused on the activity of the senses in the brain, each focused on a different sense.
“I found that researchers of vision, for example, were investigating only the visual cortex,” he says. “They met one another only at conferences. The same with those studying hearing. Some were exploring music, others were investigating language, but all of them dealt exclusively with hearing. And so on.”
The roots of this method lie in the fledgling period of brain research, when scientists approached the contents of the skull the same way they approached the abdomen. After having understood what the kidneys do, what the stomach does, what the liver does – they hoped that the brain, too, would prove to be comprised of some sort of secondary parts, with each having a clear and defined task. It was only at a later stage, thanks to scientists among Amedi is numbered, that it emerged that the boundaries that had been demarcated between the regions of the brain were perhaps convenient for classification purposes, but were obscuring complexity and versatility that were becoming increasingly apparent.
“As a student, I tried to think of all the experiences that were important to me in life, and I couldn’t think of a single one that didn’t involve several senses in parallel,” Amedi says. Swimming, eating, hiking, sex. There is hardly a human experience that is not multisensory. Why study each sense separately?
For his doctorate, which he completed in 2006, Amedi investigated a particular region of the visual cortex. Located in the back of the head, this region takes up about 30 percent of the cerebral cortex. This vast and labyrinthine area has been studied by vision researchers years, and rigorous classic work revealed the subregions one after the other. There is one region in which the image that is received from the eye is presented on a kind of internal screen, pixel by pixel; there’s a region that is dedicated to facial identification, another identifies body movements (but not faces), and yet another specializes in identifying the shape of letters. Amedi set out to study a particular subregion in the visual cortex known as the lateral occipital complex, which had been discovered by his doctoral supervisor, Prof. Rafael Malach, from the Weizmann Institute of Science.
The LOC identifies specific objects, like a can of Coca-Cola, but is far less active when the eyes are required to identify a more abstract object (like silk). Amedi wanted to know what happens in the brain when a person is asked to identify the can without the use of his sense of vision. “Back then I used to go on hikes,” he notes. “When I didn’t have a flashlight I would identify objects in the tent with the sense of touch. I asked myself, ‘Maybe there is a region like the LOC in the region of the sense of touch in the brain?’ I looked for information on the subject in the scientific literature and found nothing.”
This was at the end of the last century, the heady days of brain research using the new functional image machine, the fMRI, which can display brain activity in high resolution and in real time. Amedi hoped to find in the cortex for touch the region that deals with the identification of objects and to plant a small flag there – in other words, to locate the counterpart to his supervisor’s discovery, but in a different one of the senses.
In a toy store he bought a variety of objects that don’t contain metal (metallic objects cannot be used in fMRI because of its powerful magnet), and then he himself entered the imaging machine and started to touch things. He saw brain activity in the region of touch, which wasn’t especially surprising. But the most intense activity was actually in a particular subregion of the LOC – that is, in a place that was supposed to function only in response to visual activity.
“It floored me,” Amedi says, “because it was turning into something of a detective riddle. Why did this region turn on, even though it wasn’t supposed to have anything to do with touch?”
On a routine day, Amedi’s lab is hard at work attempting to harness the existing senses to the creation of super-senses – such as seeing heat like a bee and being able to discern objects behind a curtain like Superman.
He continued probing the matter. Among other tests, he studied what happens when subjects were asked to identify an object, such as a hammer, by means of the sound it makes when it’s used. The region was not turned on. The explanation is that the brain does not need to pass through shape in the course of identifying the origin of a sound.
“You hear barking outside the window,” Amedi says. “Do you have to conjure up a dog in your mind’s eye in order to understand that it’s a dog?”
Subsequently, Amedi had people who were blind from birth identify objects by touch, and that particular region in the LOC – which in the meantime had been named “lateral occipital tactile-visual” – responded distinctly.
“The riddle grew more complicated,” he explains. “What in the world does that region do?”
The discovery was fascinating in itself – another crack in the wall of the standard approach, according to which the cortex is divided into separate regions, each dedicated to its own sense. “To this day that’s what the textbooks say,” Amedi notes. But the discovery would turn out to be of deeper significance.
A few years later, after returning to the Hebrew University from a postdoc at Harvard, Amedi wanted to find out what else the LOtv region activates. That’s an important question, because the answer to it touches on the core of a critical issue in brain research: the organ’s plasticity.
Most scientists today agree that early in life the brain is highly flexible, but that afterward it “hardens,” as it were, and many possibilities that were previously open to it are closed. In the wake of the studies by Nobel laureates David Hubel and Torston Wiesel, for example, it became apparent why in the first years of life there is a critical period during which the brain’s visual region can be stimulated. Hence the great efforts that are made to discover and correct lazy eye in infants. A lazy-eye condition occurs when for some reason (such as strabismus, a “cross-eyed” condition) the brain does not receive proper images from both eyes that can be integrated to produce three-dimensional vision. In this situation, the brain chooses an image that is received from one eye and ignores the other. As a result, the region of vision in the brain does not develop as it should at such ages, with resultant damage that is usually irreversible. In contrast, an adult can have one eye shut for a month without any adverse effects.
Because congenitally blind people do not implement the sense of vision from birth, their region of vision would be expected to be atrophied. That’s one of the reasons for Amedi’s surprise at finding activity in that region of the brain when they felt objects. But it could be argued that this was just a lucky break. Let’s say that by chance, this region of the brain is activated by touch as well. That would conflict with several accepted notions, true, but it could be seen as a kind of exception to the rule. Amedi wanted to prove that his LOtv was unrelated to touch, vision or any specific sense. He wanted to ascend to a far more abstract plane and prove that this area of the brain, though situated in what’s called the visual cortex, has a far more recondite function: the rendering of a three-dimensional shape, unconnected to the question of the sense from which the input originates and on whose basis the shape is constructed.
The most refined way to prove this proposition was to find a method that would cause a person to perceive a three-dimensional shape of an object by means of technology that he – and no one else, either – had ever tried. For example, if you could successfully train someone to see in three dimensions through music alone, a skill for which evolution had definitely not prepared humans (unlike mole rats, for instance), and then you see that this gradually turns on that region of the person’s brain – you would demonstrate the nature of the region you’ve discovered and in the same breath confirm the hypothesis that the brain is far more flexible than science had thought. That’s what Amedi and his team did.
Next in line is a horse
How can people see by means of sounds? In his studies, Amedi expanded upon the work of his predecessors, among them the late Paul Bach-y-Rita, from the University of Wisconsin, one of the fathers of the study of neuroplasticity. The method, in a certain sense, is simple: to convert the input suitable to a damaged sense into input that is available to a different sense. In the world of cybersecurity, this would be called hacking: use of a dysfunctional sense, by means of a back door entry to it via a functioning sense.
That’s actually synesthesia, isn’t it?
“The mixture of senses that happens in synesthesia is spontaneous,” Amedi explains. “It’s our great dream as researchers of sensory transformation, and it’s far more widespread than people think. There are millions of people in the world who are prone to synesthesia, and many of them have no idea that their experience is different from that of the rest of humanity. But – and this is an important but – they have no control over the connection.
“Each of them has his set of triggers, for example auditory triggers, that create a certain visual experience, for example a shape of lightning. The brain is equipped with the ability to convert sounds into sight, but with them it’s random and arbitrary. We are trying to create something orderly that won’t apply only to a small and very limited number of triggers.”
In other words, Amedi’s technology succeeds in freeing the wild horse of synesthesia that resides in the brain of every person, and at the same time tame it to suit the individual’s needs.
In his research, Amedi has trained congenitally blind people to represent an image in the brain by way of sounds. High sounds represent the upper part of the image, low sounds the lower part. The stronger the sound is in the right ear, the more it represents the right side of the image, and vice versa. For example, a melody that starts high in the left ear and concludes low in the right ear, represents a diagonal line descending from left to right. A melody that starts high in the right ear and concludes low in the left ear, represents a diagonal line descending from right to left. If I play both melodies at the same time, the result will be two diagonal lines that intersect in the middle: You will have just read the letter X through your ears.
We found that the ability to translate a sound into an image is universal. The brain can be reprogrammed, you can be turned into a bat or a dolphin within 10 or 40 hours.Amir Amedi
Apropos horses, the walls of Amedi’s lab at the IDC, Herzliya are decorated with posters depicting two horses, a souvenir from one of his publications on this subject in the important journal Nature Neuroscience. On the right is a regular painting of a horse, the input received by EyeMusic; on the left is the output: a kind of ghost horse created from connecting all the dots that represent the sounds heard by the subjects. It’s a somewhat vaguer image, a bit blurry at the edges, in shades of black and white, but undoubtedly a horse. The blind subjects identified it without difficulty.
In a series of papers published in recent years, Amedi and his colleagues have showed that when visual melodies are played for a person who is blind or blindfolded, at first nothing is turned on in the visual cortex. Only after training do the regions act in accordance with the mission: If faces are played, the face region will act; if shapes of letters are played, the letters region will act; and if objects are played, the objects region will act.
“About 20 congenitally blind people were trained in the system, as well as many, many more who became blind at an advanced age and also sighted people who were blindfolded,” Amedi says. “We found that the ability to translate a sound into an image is universal. There was not one subject, seeing or blind, who was not successful in learning the algorithm and translating sounds into visual representation. It doesn’t matter whether you were able to see in the past or not, or whether you have a musical background – everyone can learn it. The brain can be reprogrammed, you can be turned into a bat or a dolphin within 10 or 40 hours.”
The development of the device was made possible in part by Amedi’s short and tempestuous career in jazz. “It helped me solve the greatest challenge in transformation from sight to hearing – the fact that we emit a great many sounds simultaneously,” he says. “Imagine randomly pressing more than three piano keys at once. To succeed in getting 15 to 20 sounds to go together well is a challenge even for composers, but we don’t have that privilege.”
The system plays automatically according to the image – not according to any sort of aesthetic preference. Hence the choice of the pentatonic scale. “It’s the scale that constitutes the basis for jazz, rock, punk and soul,” Amedi notes. “Every combination of sounds in it will come across at least reasonably.” The professor’s background in music also made it possible for him to render his system colorful, by introducing instruments each of which represents a different hue. A trumpet, for example, is blue, a violin yellow.
What exactly do the congenitally blind experience when they “see” in this way for the first time?
“I don’t know what they experience, because they don’t have our language,” Amedi replies. “You talk to them and you don’t know how to ask the question,” he adds, referring to the sightless individuals who volunteer to take part in his experiments, with whom he’s maintained a warm relationship throughout his career.
It’s easier to find out about the experience from people who became blind when they were adults. Amedi is currently working on an article about a person who was able to see all his life and suddenly became blind 20 years ago.
“He reports that in the first hours of training with the system he only hears,” Amedi says. “But after 20-30 hours of training he describes feeling that a region that was dormant in his brain for a very long time is awakening, and he starts to see pictures.”
Amedi thinks that if a congenitally blind person uses his method for a lengthy period, say two years, experience will develop within him over time that resembles vision in a healthy person. In the scientist’s fantasy, which is a bit difficult to realize, of course, he would want to let an infant who was born blind train in the system regularly. Would the infant experience vision? That question remains in the realm of theory for the time being, like many other questions relating to EyeMusic. In the meantime, the system is fated to remain confined to the lab, because its daily use is liable to be dangerous. Turning it into a usable device is a highly complex process involving complicated regulation.
“Imagine a blind person walking in the street with your system and falling – you’re in trouble,” he says, but adds that the system will overcome such problems “at some point.”
The difficulty of turning EyeMusic into a practical instrument that can assist people in the real world has pushed Amedi in a different direction, one that is occupying him now: developing a kind of listening device that works through vibration of the fingers. The research in this field is simpler, the training of the subjects shorter, and there’s no fear that you’ve caused someone to collide with a pole or wander by mistake into the street. The idea is to intensify the auditory ability of people who are hearing-impaired through the sense of touch. It’s standard practice today to provide the hard of hearing with a cochlear implant, which improves hearing ability in some instances but can be unreliable under certain difficult conditions.
Amedi explains that a person with the implant can get along in a quiet environment but will have trouble on the street, especially if everyone who speaks to him has a surgical mask covering their face, as is often the case today.
The difficulty in understanding what’s being said through a face mask is a classic example, he says, of our tendency to use several senses at once in order to decipher information in the quickest and most precise way. According to Amedi, when the speaker’s lips are concealed, the listener’s ability to understand decreases dramatically – a drop equal to a 10-decibel reduction in volume. The exact same effect, only in reverse, is created by the vibration of the fingers. According to the findings of Amedi and his colleagues, whose publication is forthcoming, after an hour of training, the subjects’ understanding improves to a degree comparable to an increase of 10 decibels.
I asked for an example. Dr. Katarzyna Ciesla, from Poland, who is doing a postdoc in the lab, placed headphones on my ears and played me a series of sentences. Through the headphones I heard a very unclear voice of a man speaking short sentences in English. The voice was deliberately distorted, and in the background a woman could also be heard speaking, making things even more difficult. I understood hardly anything. Then I was asked to place two fingers in a small box with holes, in which there were two small vibrating surfaces. These surfaces vibrated with the frequency of the man’s remarks and helped me understand what I was hearing – by means of my fingers.
I underwent some brief training, far shorter than what’s planned in the experiment, yet even so my identification ability improved by 80 percent. It was an odd sensation: I suddenly felt that I was capable of hearing through my fingers.
We want to start working with the same techniques, of expedited evolution of the brain, using technology and training, with people like you and me. We want to discover if that will cause the brain to develop new areas.Amir Amedi
In general, these experiences are not alien. Everyone who understands immediately what’s meant when he reads a restaurant review that mentions “bright flavors,” or hears the announcer of a music program talk about “the color of sound” knows what it’s all about. Suddenly I remembered my legendary music teacher from the eighth grade in Haifa, Drora Brissman, who related how, as a student, she would lie on the floor while listening to a recording of the “St. Matthew Passion,” in order to listen to Bach’s divine oratorio through the body, too.
A funny dwarf with pouty lips
Amedi is a tough interviewee, and that’s not meant as a criticism. The attempt to follow what he says and to decipher his articles, which are rife with jargon from the fields of neural computation and brain anatomy, could quickly wear down the intellectual abilities of an average journalist. His speech is rapid and associative, and he has a tendency to bombard the listener with accounts of studies he’s already written or will write in the future, of outstanding findings made by his colleagues and of technological developments intended for the general public that are based on his ideas. Each of the several encounters with him, face-to-face and via Zoom, lasted three or four hours and ended with the interviewer drained while the interviewee looked as if he’d just emerged from a shower, ready to move on to the next meeting on his crammed schedule. On my way out after our second conversation, one of his team members handed me four articles he’d printed and bound for me, together with a disk containing 76 more articles, so I’d having something to read at bedtime.
Amedi’s approach is multidisciplinary and multitrack, and at times those paths collide. For example, he has studies that reveal the hidden visual ability of blind people. On the other hand, he also has done research showing that certain sections of the cortex of blind people that are today inactive in the brain were mobilized during the person’s infancy to reinforce their memory and linguistic abilities. That happens to a degree even to sighted people who volunteered to spend five days blindfolded.
Only recently has a new finding emerged, one as yet unpublished: The left thalamus, which is a relay station for visual information in the center of the brain, is also mobilized by the blind for purposes of memory and language.
These are astonishing findings, which, like others, shatter accepted conceptions about the division of the cerebral cortex and even about its traditional division into high and low. What do neurons in the visual cortex have to do with memory? What does the thalamus, which lies deep under the cortex, have to do with complex language tasks, which are generally attributed to the cortex alone?
“Blind people resort to language and memory far more than we do,” Amedi explains. “When they ‘watch’ a soccer match, for example, they need to understand and remember far more than you do. One region of the brain can become something completely different, because what is not in use will be seized by what is important.”
Another area that the professor is currently dealing with involves the use of sounds to help people suffering from anxiety. He began to take an interest in this after he himself started meditating during a sabbatical and discovered how relaxed he became thanks to a typical meditative exercise: With eyes shut, one scans the body systematically, from toes to head. He started to have people enter an fMRI machine (currently, he uses the machines of others, but very soon will have his one in the lab) and be subjected to an internal body scan. “We saw that when attention is directed to a systematic body scan, there is a great quieting of the emotional system in the brain.”
But not everyone can handle meditation of that sort. My concentration on my body, for example, is very elusive.
“True,” Amedi shot back, eyes glittering, “there are people for whom it works less well. Their head is drawn to other things – to a coffee pot, to tasks they have to do, to a quarrel they had in the morning. So we are trying to create external means that will draw the mind’s eye to the right place in the body in order to continue the scan.”
This is one of the uses of a special acoustic room that was built in Amedi’s lab at a cost of hundreds of thousands of dollars. The walls are coated with materials for acoustic absorption, to which are attached 97 top-quality loudspeakers that surround you from every direction. When one lies on a bed in this room, the combination of the sounds creates the illusion that the sounds are emanating from one’s body – from the leg, for example. When a sound emanates from your leg, it’s much easier to concentrate on it.
To understand how sounds can be made to come out of different parts of the body, it’s necessary to understand how the brain locates a sound. Amedi asked me to shut my eyes, clicked his fingers from various directions and asked me to identify the direction from which the sound came. The reason I can do that, he explains, is that the brain is able to locate sounds by calculating the difference in intensity and the speed of the input that arrives from each ear. This is the three-dimensional aspect of hearing, which resembles three dimensions in seeing and is created by the brain by combining the images that arrive from each eye.
Obviously, the intention is not for people to spend a fortune installing rooms like this at home. The idea is to place sensitive microphones in the ear, to record the combined sounds received from all the loudspeakers in the room, and to play them afterward outside the room for people via simple earphones.
My thoughts wandered again: I thought of myself sitting, for example, in a train, and instead of listening to Ofer Levi on Spotify, I hear my sole-calf-thigh tweeting me. Is that relaxing or not? It remains to be seen, but there’s no doubt that it fires up the imagination
If it’s possible to augment one’s ability to concentrate, or to allow blind people to see the visible light spectrum (by using sounds) – why can’t we install in the musical eye a camera that detects infrared light as well? Anyone, blind or not, equipped with such a system would be able to see in the dark using their ears. And why not install an ultrasound detector so as to see through walls? Or an ultraviolet camera that would allow people to see the world as a bee does? When it comes to improvements, the sky is the limit as far as Amedi is concerned.
“We want to start working with the same techniques, of expedited evolution of the brain, using technology and training, with people like you and me,” he says. “We want to discover if that will cause the brain to develop new areas.”
The community of neuroscientists in Israel views Amedi as a researcher with fine credentials – namely, publications in highly regarded journals and projects involving distinguished international cooperation. The only critique I heard of him, which one colleague voiced affectionately, is that he’s not always conservative enough in interpreting his findings.
“He’s a very creative scientist, provocative and stimulating,” the colleague said. “In many cases he’s right. Sometimes he goes a bit too far in his thinking – but we all do that. Everyone falls in love with his ideas.”
But what good scientist doesn’t occasionally commit the sin of over-enthusiasm?
One of Amedi’s more dramatic claims is that he might be drawing close to locating the mysterious connection in the brain between body and mind. That possibility began to take shape in the wake of a series of new and intriguing studies aimed at finding what’s referred to as the “little people” in the brain: At the center of the cerebral cortex there is a long strip that constitutes a sort of map of the data of sensation and movement that arrive from the body. The representation of the different body parts on this strip is not proportional. Sensation in the back, for example, is meagerly represented (ask someone to touch you on the back with one finger and then with three fingers – you won’t know the difference).
Other body parts, though, are overrepresented. If a human body were to be sculpted according to those proportions, the result would be a funny dwarf with pouty lips, huge hands and a grotesquely large sexual organ. That dwarf continues to appear in the nightmares of everyone who learned about him in university.
That strip in the brain, discovered in the mid-20th century by the Canadian neurosurgeon Wilder Penfield, is called a homunculus – a small person. Amedi says that his studies have turned up more than 15 additional homunculi like this, scattered throughout the brain. It’s another discovery that indicates the blurring of the boundaries in the brain: There is not only an “emotion region” and a “sensation and motion region,” but also an interplay between them. Among other discoveries, Amedi found a map of the body’s representation (which resembles the homunculus) in the amygdala, which is thought to be the center of fear in the brain.
According to another finding, as yet unpublished, a similar map also exists in the brain’s default network – which comprises a number of regions and the connections between them – has been the subject of increasing attention in recent years. This network is the part of the brain that is active when we are not engaged in any special activity related to the external world, such as lying down with our eyes open. It’s there that thinking, planning, remembering and daydreaming take place.
In a certain sense, this is the network that represents our internal world, our self, in contrast to the parts of the brain that deal with fulfilling tasks relating to the external world – such as reading, listening or moving the hand in order to lift a cup. Wikipedia (in Hebrew) states explicitly: “The default network… is anatomically and functionally distinct from the networks involved in functions of sensation.”
But Amedi thinks that both sensation and motion are present in the default network – something that is of great significance.
“It was always known, both in the world of the spirit and in classic psychiatry, that a deep connection exists between the body and the mind,” the professor explains. “But no one in the world of brain research had any idea where exactly that connection takes place in the brain. Now we have arrived at a series of discoveries, only a small part of which have been published – the rest are forthcoming – that provide us with a lead to that connection. Every person who meditates is familiar with it – we are discovering where it takes place in practice, what its neural infrastructure is.”
Amedi emphasizes that he does not yet understand fully the meaning of his findings. “It hasn’t yet coalesced into a story,” he says. “We don’t have a complete theory. It’s a preliminary scientific proof, but quite dramatic.”
These discoveries could lay the foundation for a host of fascinating additional studies. Once the emotional-physical interface in the brain is found, all manner of ways can be explored for reprogramming it to assist people suffering, for example, from psychosomatic illnesses, from irritable bowel syndrome to headaches.
This research direction may or may not bear fruit, but it’s difficult not to be swept away by Amedi’s drive on this subject, and indeed vis-a-vis everything else he is working on as well. If you shut the door on him he will come through the window, and if you close your eyes he will enter through another sense.