Read an Excerpt
Preliminary Remarks and Safety Precautions
Doubtless you drive a car, and you wash your laundry in a washing machine. You use a mobile phone, surf the Internet, shoot your own vacation videos, watch television, and listen to music on CDs. I don’t know what other useful or useless gear you may have acquired in the course of your life. But one thing I know for sure: the more complicated and more expensive the equipment was, the more carefully you studied the instruction manual that came with it that described how to use it and how to enjoy it for the longest possible time.
You also possess a brain. And you use it more often than you think. At least much more often than you use all your other gadgets and machines. You use it to get along in life and, at least now and then, you get a little pleasure out of it. But you have, until now, never consulted a user’s manual for it. Why not?
Have you simply assumed that your brain is already working properly all by itself? Then unfortunately you have been making a mistake. It only works the way it does due to the circuitry that has been installed in it. And this circuitry—as well as all the further problem-solving circuitry that can be installed in it in the future—depends very much on how you have used your brain so far and what for. So maybe it would have made sense to have checked up sooner on how you were using it. It might conceivably be the case that your usage pattern so far has been leading to a future in which there will be many tasks beyond your brain’s capacity.
Or have you simply been taking the approach that, since you have not had to spend a lot of money on this thing and have simply always had it, it needs no further attention on your part? That is also a mistake. There are many other things that just come your way as gifts that are not dead but still living and developing—like children, like relationships, yes, even like your dog or your vegetable garden—all of these need very special attention and painstaking care. And this is true for your brain as well.
Or you may have been hoping that an almighty creator made your brain—or else that your almighty genes have shaped it—once and for all in such a way that it is ideal for taking care of you in this world in the best way possible, and thus there is nothing about it that needs changing. It is nice to think that either He or they (your genes) are responsible for what becomes of your brain instead of you, but this assumption is also a mistake. It is true that every human being’s brain is different. Each brain is unique, and from the very beginning each one has had very specific weaknesses and very specific strengths and abilities built into it. But what becomes of this basic makeup of your brain in the course of your life—whether particular weaknesses are compensated for or made even worse, and whether particular abilities are developed or suppressed—depends on how you use your brain and what you use it for.
This may all sound a little disturbing, but sticking your head in the sand won’t change it. You’ll have to pull your head out of the sand at some point, and admit that your rationalizations are not really solid, but are just plain old excuses. There is only one good reason you can put forward in good conscience for why you haven’t yet given any thought to how you use your brain: no one has ever explained to you why you should. That is why I have written this user’s manual for you, and I am very happy you have come across it.
I have been working for many years in the field of brain research. Like many other scientists working in this field, I have tried to find out how the brain actually functions. Like all the other researchers, I went as far as I could in cutting up the brains of experimental animals into smaller and smaller component parts and measuring whatever there was to measure about them. I have grown cultures of the various types of brain cells in laboratory dishes and have observed what they developed into and what they were capable of doing. And like so many other brain research scientists, I have done experiments with animals—mostly lab rats—to investigate the effects of various treatments and surgical interventions on their brains.
I still find it fascinating how much there is to dissect, measure, and study in such a brain. But by now I no longer believe that we can succeed in this way in understanding how any brain, to say nothing of a human brain, functions. On the contrary, this kind of research leads us to regard whatever can be especially easily dissected, measured, and studied as being of particular importance in the functioning of the brain. And because researchers are quite happy to talk about that which seems particularly important to them, and because the media are quite delighted to publicize these kinds of new developments, more and more people have gradually come to believe, for example, that happiness results from heightened endorphin secretion, that harmony is produced by plenty of serotonin, and that love comes from particular peptides in the brain. They think that the amygdala is the source of fear, the hippocampus is the source of learning, and the cerebral cortex is the source of thinking. Now in case you have heard of any of this stuff, you can just go ahead and forget about it. The same goes for any claims that particular genetic configurations are responsible for what goes on in your brain. There are no genes for laziness, intelligence, melancholy, addiction, or egotism. What do exist are different basic tendencies, characteristic predispositions, and specific vulnerabilities. But what ultimately becomes of these depends on the conditions for development each of them encounters.
But overvaluing the partial pieces of knowledge that scientists gallop after in the latest high-tech boots is not the only obstacle to understanding what goes on in our brains. Another big problem can be compared to stumbling around in old shoes that have long since ceased to fit. Ideas that appear and for various reasons are regarded during a certain period as extremely accurate, later frequently come to be regarded as dogmas and are presented as such, often by highly respected and admired authorities. Such notions tend to persist for decades. Now if conceptual models describe accurately the realities they refer to, there is no reason to oppose them. But since they only rarely do, most theories in time become like dreadful, ill-fitting shoes that are a major impediment to forward movement.
I myself, like many scientists in the field of brain research, have spent a long time walking around in these kinds of old shoes. The idea that oppressed me the longest and the worst was the dogma that the brain’s neuronal circuitry is immutable once it has taken form. This idea was put forward by a pioneer in brain research, Ramón y Cajal. At the beginning of the twentieth century, through the use of new staining techniques, he discovered that the brain is not just a big undifferentiated pudding (a so-called syncytium), but is composed of a countless number of nerve cells that stay in contact with each other through their multi-branched extensions. By means of his stained cross-sections of the brain, he was able to show that this whole thick tangle of nerve-cell extensions gets denser and denser in the course of the brain’s development, but that later on, in old age, it begins to thin out to one degree or another. His conception of the brain was adopted by subsequent researchers, and for nearly a century it shaped the thinking of most neurobiologists, psychologists, and psychiatrists. It also became established as a basic conviction in the minds of certain circles in the general public.
In the meantime, it has emerged that the brain remains structurally malleable to a great degree even in adulthood. It is true that after birth, nerve cells can no longer divide (with a few exceptions); however, throughout the lifetime of a human being, the nerve cells of the brain do remain capable of adapting their complex patterns of interconnections to new conditions of use.
The most important and lasting influence in humans on how the neuronal networks and interconnections existing in the brain are used is a thing that is particularly difficult to measure. The best term you can come up with to describe it is experience. This refers to the knowledge built up in the memory of an individual about strategies for thinking and behaving that have proved particularly successful or particularly unsuccessful in his life up to the present, that have been confirmed as such again and again, and that, consequently, he now considers particularly appropriate or inappropriate for solving future problems. Such experiences are always the result of a subjective evaluation of his own reactions to perceived changes in the external world that he regards as significant. As results of subjective evaluation, they are distinct from all (passive) experiences and (passively) adopted knowledge and skills to which he has as yet to attribute significance for coping with the problems of his life. Because he becomes embedded in a system of social relations that keeps getting more complex—this normally starts in early childhood and then goes on actively later in life—the most important decisions a human being can make in the course of his life are psychosocial in nature.
It took a long time for me to finally realize that what guides us in all our decisions is not our mind or our consciousness. It is also not the knowledge that we have learned by rote or have adopted from questionable sources. Rather, it is the experiences we have accumulated in our development up to now. The experiences a person has had in the course of his life become firmly anchored in her brain. They define her expectations; they steer her attention in very specific directions; they determine the valuation she puts on what she lives through and how she reacts to her surroundings and what impinges upon her from the outside. Thus in a certain way, these individually acquired experiences are the most important and most valuable treasure a person possesses. She can use it not only for herself but also try—especially if she has ever had the experience that giving brings a great deal of joy—to pass it along to others. The special quality of this treasure trove of experience is that in using it and sharing it, it does not become smaller but gets bigger and bigger.
And if you happen, as I do, to work as a brain researcher in a psychiatric clinic, you not only acquire new experiences, but certain new thoughts and concerns arise in your mind as well. I see patients who are overwhelmed by certain feelings and emotions and have lost the ability to control them. Driven by these emotions, these people sometimes develop ideas that appear to outsiders to be crazy. Many of them feel persecuted or feel that they are being controlled by alien forces. Some have the feeling that they are falling apart or breaking down into different personalities. Some develop feelings of omnipotence and maybe think they are God or Napoleon. Still others feel small and negligible. Others are compulsively driven to be in control of something or other.
On the other hand, I also sometimes see people who are not patients but who are nevertheless driven in a similar way by certain feelings. There are people who consider themselves indispensable and think their opinions are universally valid, and people who have a low opinion of themselves and either prefer to keep their mouths shut or only to repeat what others say. There are people who are dominated by the feeling that they must acquire power and influence and are ready to do anything to attain this goal. And there are those who simply want to be left alone and who are indifferent to practically everything that goes on around them. There are those who simply have to get excited about everything, and those who have a continuous and urgent need for distraction. Many are only capable of keeping at bay the continual flare-ups of malaise and discontent they undergo by means of immoderate eating or with the help of legal or sometimes illegal drugs.
Not only in clinics but everywhere, there are people who behave self-destructively, inconsiderately, egotistically, narcissistically, with indifference, calculatingly, contentiously, self-importantly, and irresponsibly and who thereby cause tremendous damage. In economic terminology this sort of damage is referred to as ‘‘friction loss,’’ and economists consider the elimination of friction loss the number one prerequisite for increasing the gross national product of any industrial country. If you ask these people why they behave in such a destructive and selfish manner, most of the time you discover that they have no idea that they do. They just have the feeling that they are behaving the way they have to behave, and that everything they do and think is somehow right for them. This is no more than just a feeling they have.
And that is why I am so inspired by the idea of investigating a little more closely the origins of people’s strong feelings and emotions. It is only in the last few years that ‘‘emotional intelligence’’ and the ‘‘net of emotions’’ have become popular and hotly discussed themes. Even psychologists and psychoanalysts are no longer content simply to point out that early experiences play a decisive role in determining later basic behaviors and emotions. Now they too want to know how these experiences are anchored in the brain. They want to know how and under what circumstances it might be possible to ‘‘overwrite’’ these engrams with new experiences, how a feeling, once developed, can be changed and replaced or overlaid by a new one. These questions have brought about a good deal of ferment in the last few years, particularly in the area of brain research. Every scientific discipline passes through certain discrete phases in the course of its development. In each phase it arrives at a particular view of the phenomena it studies. On the basis of the understanding it has arrived at up to that point and the knowledge it has accumulated, it builds a specific theoretical structure. To begin with, this structure is still more or less wobbl. Therefore specific attempts are made to brace it with solid building blocks. It is then further consolidated by means of various organizational measures, and protected as well as can be against the destabilizing influence of undermining ideas and conceptions. But despite all this there is something for which there is no complete defense: the additional knowledge that inevitably arises when investigators do further work on particular questions, think further about the relationships among phenomena, and seek solutions to problems. This new knowledge must somehow be integrated into the old theoretical structure. So long as that can be successfully done, everything is fine, and the edifice remains standing a while longer, even though it gradually takes on a more and more eclectic look, in the form of annexes, gables, turrets, extra wings, and storage areas. At some point, however, the building becomes so hard to get around in (so difficult to have a unified understanding of) and begins to look so bad in the landscape that a drastic reconstruction of the old pieced together heap of theoretical structure becomes inevitable—or even a completely new building becomes necessary. In these phases of upheaval, an old paradigm that everyone had before found completely satisfying is replaced by a new one. The new paradigm offers the possibility of relating to all the knowledge that has been accumulated up to that point as still valid, but it integrates this old knowledge into a new structure that also provides room for new knowledge because it is more comprehensive, more inclusive, and just broader than the old one. These phases of upheaval are the most exciting phases in the development of a scientific discipline—less exciting for those who have made themselves completely comfortable in the old house, but more exciting for all those who felt the old house was too confining, too musty, and just too hard to see their way around in.
The classical natural sciences (astronomy, mathematics, physics, and chemistry) already have this kind of paradigm change behind them. They have all passed through a phase in which they first accumulated, described, and sorted observable phenomena. Then things were all broken down into their component parts, and wherever possible, the properties of these parts were studied as precisely as was possible. After a long enough time had passed in which scientists tried futilely to understand the whole out of their increasingly precise knowledge of the parts, a stage was eventually reached where some of them began to look for invisible forces and dimensions hidden behind objectively observable and measurable phenomena. Names like Copernicus, Kepler, Schrödinger, Einstein, Bohr, Heisenberg, and Planck are associated with these turning points in our understanding of the world on the level of the classical natural sciences. But since most people couldn’t care less if the Newtonian laws are only valid when things are neither too small nor too big, if there is such a thing as bent space, if time is only relative, and if waves and particles are interchangeable, these new ways of looking at things have not had that great an effect on our lives and on our way of seeing ourselves.
On the other hand, in biology things are quite different, as they are also in brain research, where the kind of transformation we are talking about is just beginning to happen. Biology is a relatively young discipline in the world of natural science, and its object—life, in all its manifold forms—is so complex that biologists in many areas are still in the gathering, describing, and sorting stage. In many other areas they have already passed to the stage of breaking things down and have begun to gain as precise as possible an understanding of component parts. They have pushed forward to the level of individual molecules, have deciphered the genetic code, and have discovered countless numbers of the signals, signal-transmitting substances, and receptors with whose help information is exchanged within cells, among cells and among organs, and finally even among organisms. They can in part precisely describe how particular life forms have arisen in the course of phylogenetic history, how the information necessary for this was passed down from generation to generation, and how it was used in the elaboration of specific physical characteristics in the course of the development of individuals.
All these are important pieces of knowledge that have contributed significantly to the fact that today we understand the phylogenetichistory of human beings better than ever before. We now understand how little human cells differ from the cells of other living beings, how little human organs differ from the organs of other mammals, and how little human modes of behavior differ from those of our relatives in the animal world. That is why Desmond Morris called us ‘‘naked apes,’’ forcing us to look at a fact that Darwin pointed out earlier but that we were completely unwilling to admit—that we are no more than a part of nature—and in some ways a very inadequately equipped part. We are not almighty beings, and certainly not the centerpiece of the world. Rather, like all the other creatures, we are embedded in nature as a whole and are dependent upon and intricately bound up with her.
And that is precisely the special point in which the findings and insights of biologists and the brain researchers differ from those of classical natural scientists. Biology and neuroscience not only provide us, as all the other natural sciences do, with ever new and useful knowledge about the world that allows us to shape it in accordance with our ideas. They also continually bring to light new knowledge about us humans, knowledge that helps us make sense of ourselves and of our place in nature.
For a long time I stayed within the old ideational structure adopted from the classical natural sciences—like so many other biologists and neuroscientists—where only one question with regard to the brain was allowed: How is it made and how does it function?
But if the structure and thus also the functioning of our brain depends in a very critical way on how we use it and what we use it for, then does not the crucial question really become: How and for what purposes should we use it so that the potentialities built into it really can be fully actualized? In this user’s manual for the human brain, I try to answer this question. I base what I have to say on data from the field of brain research that have come to light only in the last few years, data that have made it possible for us, today better than ever before, to understand why and how the way we use our brains makes a difference.
For decades the presumption was that the neuronal pathways and synaptic connections established during the brain’s initial development were immutable. Today we know that the brain is capable throughout our lifetimes of adaptively modifying and reorganizing the connective pathways that it has laid down, and that the development and consolidation of these pathways depends in quite a major way on how we use our brain and what for.
A few years ago, no researcher in the field of brain science could have conceived of the possibility that what we experience could be capable of changing the structure of our brain in any way. Today most scientists who study the brain are convinced that the experiences of our lives do become structurally anchored in the brain.
Until quite recently, it was held to be self-evident that human beings have a big brain to make it possible for them to think. However, the research results of the last years have made it clear that the structure and function of the human brain is especially optimized for tasks that we would subsume under the heading of ‘‘psychosocial competence.’’ Our brain is thus much more a social organ than it is a thinking organ.
As recently as a few years ago, everything that had anything to do with feelings and emotions appeared suspect to brain researchers. But lately they have begun to understand how important feelings and emotions are, not only in orienting perceptual and thinking processes, but also for the way in which early experiences become anchored in the brain. Thus the great role feelings play in determining our later basic attitudes and convictions has become clear.
For an entire century, it was hotly debated whether the thinking, feeling, and behavior of human beings was determined more by inborn behavioral programs or by experiences acquired in the course of our lives. Nowadays advocates of psychological and psychosocial determinism are beginning to accept the view that human feeling, thinking, and behavior have a material, that is to say, a neurobiological basis. On the other side, believers in the biological determinism of psychological phenomena have come to acknowledge that, at least in humans, psychological processing of social experiences is of considerable importance, both for the stabilization of particular genetic inherencies within a population and for the formation of particular neuronal and synaptic connective patterns in the brain.
A lot of this new data, which has appeared in a flood of scientific publications in the field of brain research, went largely unnoticed by its potential users, such as doctors, therapists, and educators. It did not receive major play in the media, and it will be years before it begins to appear in school textbooks. The fact that so many people understand either nothing or very little of what is going on in their heads and the heads of their fellow human beings makes both the writing and reading of a user’s manual for the human brain a difficult undertaking, and one that is not without dangers. I have made an effort to write this text in such a way that the most complicated part is found at the beginning, right here in these preliminary remarks. If you have gotten this far, then the rest is child’s play.
But watch out: this child’s play could get serious fast. If that happens, it might happen that nothing will end up the way it was before. Including your brain.