We Are Our Brains (36 page)

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Authors: D. F. Swaab

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And so it was, through damage, disease, and a process of backward reasoning, that the functions of the prefrontal cortex gradually came to light.

MORAL BEHAVIOR: THE HUMAN IN THE ANIMAL

My object in this chapter is to shew that there is no fundamental difference between man and the higher mammals in their mental faculties.

Charles Darwin,
The Descent of Man

Adherents of the Intelligent Design movement believe that morality has no biological basis but is given to man through God's grace and
that believers were at the front of the line when it was handed out. In
Schitterend ongeluk, of Sporen van ontwerp?
(Glorious Accident, or Traces of Design?) a book on Intelligent Design edited by the nanotechnologist Cees Dekker and others (2005), Henk Jochemsen, a molecular biologist and professor of neo-Calvinist philosophy, stated, “From the point of view of sociobiology and evolutionary ethics, truly altruistic behavior is biologically perverse and pathological, because it conflicts with human nature. Yet most cultures and great religions designate true altruism as a higher ideal.”

Anyone who is familiar with the writings of Darwin or the Dutch primatologist Frans de Waal knows that Jochemsen's claim is nonsense. Over a century ago, Darwin was able to describe in detail how our moral awareness developed from social instincts that are important for the survival of the group. This type of behavior can be observed in all species whose members need to work together, like primates, elephants, and wolves.

Empathy—the capacity to recognize and share the feelings of others—provides the basis for all moral behavior. I remember being struck by the way in which our dog showed empathy for her playmate, our daughter's dog, after the latter's paw had been operated on. The two normally frolicked around wildly with one another, but after the operation our dog approached her friend very cautiously, sniffing as she did so, and remained motionless for a very long time, gazing at him and occasionally whimpering quietly to show her sympathy. She then went up to my daughter's dog and began very carefully to lick the paw that had been operated on. Similarly, when an elephant is hit by a bullet or a tranquilizer dart, other elephants trumpet loudly and try to help the victim back on his feet by pulling at him with their trunks or pushing him with their bodies, sometimes for hours on end.

Many moving instances have been described of truly moral behavior among animals. In one zoo, an old, sick bonobo ape was placed with a group of fellow apes. Other bonobos saw how confused he was by his new surroundings, took him by the hand, and led
him to where he was supposed to be. When he then got lost and cried out in alarm, the others went to him, calmed him down, and brought him back to the group. You'd be lucky to encounter such civilized behavior on the streets of Amsterdam!

The fact that primates possess moral awareness is also evident from the empathy that they display toward other species. A bonobo's attempts to comfort an injured bird can be ascribed only to pure empathy. In 1996, a female gorilla named Binti Jua rescued a three-year-old boy who had fallen eighteen feet into the primate enclosure at a zoo near Chicago. Other species, too, can sacrifice themselves to save humans. A labrador in California gave new meaning to the phrase “man's best friend” when he jumped in front of his master to intercept a rattlesnake's bite. Dolphins are known to come to the aid of swimmers in addition to helping other dolphins caught in nets. Empathizing with and helping others may lie at the heart of human morality, but such behavior has a long evolutionary history and certainly isn't exclusive to humans.

These few examples alone show that Cees Dekker, a radical Christian who was formerly the most vocal proponent of Intelligent Design in the Netherlands, got it completely wrong when he claimed morality as an exclusively Christian trait. In an interview with the Dutch daily newspaper
De Volkskrant
(March 4, 2006), he stated, “Jesus said love God with all your heart, and love your neighbor as yourself. That's a moral precept, a law that's hard to fathom and that doesn't lend itself to investigation by scientific methods. Yet man can distinguish between good and evil.” It would seem that adherents of Intelligent Design don't read the writings of those they criticize. As a result, they aren't forced to conclude that religion didn't invent moral precepts but simply took them over after behavior of this kind had evolved among social animals, including humans.

UNCONSCIOUS MORAL BEHAVIOR

The greatest tragedy in mankind's entire history may be the hijacking of morality by religion.

Arthur C. Clarke

Moral precepts serve to promote cooperation and support within social groups; they also act as a social contract, imposing restraints on the individual to benefit the community at large. As might be expected, Darwin's theory of moral psychology (1859) traced the emergence of ethical behavior not to selfish competition between individuals but to social solidarity within the group. As they evolved, humans developed altruistic behavior, based on the loving care shown by parents toward their offspring. Altruism was then extended to others of the same species according to the principle “Do as you would be done by.” Such behavior, the product of millions of years of evolution, was ultimately made the cornerstone of human morality, a code of beliefs that was only recently incorporated into religions, a mere couple of thousand years ago. It's perhaps worth interjecting here (a touch cynically) that of all the stimuli that bind communities together, having a common enemy is the most powerful of all—a mechanism that many world leaders have exploited.

Inherent in the biological objective of morality—promoting cooperation—is that members of one's own group receive preferential treatment. Loyalty to the nuclear and extended families comes first, followed by loyalty to the community. Once your own survival and the health of those closest to you are assured, you can extend your circle of loyalty. “First grub, then morals,” as Bertolt Brecht put it. These days we're doing so well that the circle of loyalty has been extended to the EU, the West, the Third World, animal welfare, and, since the Geneva Conventions of 1949, even to our enemies. However, the need for this approach was felt as far back as the third century
B.C.
, when the Chinese philosopher Mo Zi, seeing the destruction
caused by war, sighed, “When will there be a path to universal love and mutual benefit? When no one claims other countries as their own.”

Although tests show no significant difference in the moral choices made by atheists and believers, the Intelligent Design movement claims that moral behavior is unique to man and derives from religion, especially Christianity. In his contribution to Cees Dekker's book on Intelligent Design (2005), Jitse van der Meer, who teaches biology at a Christian university, writes, “Humans are the only primates who are capable of moral thought.” However, primatologist Frans de Waal has shown that people usually don't think at all about moral acts. Instead they act quickly and instinctively, on a biological impulse. It's only afterward that they think up reasons for what they did unconsciously in a flash.

Our moral values have evolved over the course of millions of years and are based on universal values of which we're unconscious. Moral behavior manifests itself at a very early stage of development. Since such behavior is also displayed by animals, it would seem to be hardwired. Before they are old enough to have acquired speech or reflect on moral issues, young children show an instinct to comfort family members who are in pain, just as primates comfort each other. In an experiment in which adults pretended to be sad, children aged between one and two responded by trying to comfort them. And this behavior wasn't confined to children. In the same experiment, pets also displayed a strong instinct to comfort. Just like eighteen-month-old human infants, chimpanzees can display altruistic behavior without the incentive of a short- or long-term reward. They will hand another chimpanzee a stick or a child a pencil simply because it's out of the other's reach. They will, moreover, do this repeatedly, again without the prospect of any reward. So the roots of our altruism go back a very long way. There's no foundation for Van der Meer's claim that “good behavior has no biological cause but must be inculcated, because it is not innate.” Furthermore, it's inconceivable that the remarkable primate research carried out by
Frans de Waal and his team on the biological basis of social behavior should be dismissed by Henk Jochemsen in the above book as the “shriveling of life sciences and social sciences to biological specializations.” It wouldn't hurt to put your unfounded ideas into perspective, adherents of Intelligent Design!

MORAL NETWORKS

Moral decisions aren't just made in the prefrontal cortex; many other regions of the brain are involved.

We have a moral network in our brains made up of neurobiological building blocks that have evolved over time. First, brain cells known as mirror neurons come into play when we observe the actions of others. When you see someone move a hand, the same neurons fire in your brain as when you make that movement yourself. Mirror neurons help us to learn by imitation—a process that's largely automatic. Newborn babies can copy the mouth movements of adults before they are an hour old. The same neurons react to displays of emotion, enabling us to sense what others are experiencing and thus providing the basis for empathy. Mirror neurons have been discovered in the prefrontal cortex (PFC,
fig. 15
) and in other regions of the cerebral cortex.

Our large PFC contains important components of our moral network; it ensures that perceived emotions are linked to moral concepts, and it reacts to social signals and inhibits impulsive, selfish reactions. It's also crucial in deciding whether something is a fair deal. The importance of the PFC for our moral awareness is evident from studies of damage to that area from tumors, gunshot wounds, and other injuries, which has been shown to cause delinquent, psychopathic, and immoral behavior. A judge in the United States suffered damage to his PFC from grenade fragments. He completely
lost the ability to relate to the defendants in court. Sadly (but perhaps fortunately for the local criminal community) he felt obliged to quit his job.

Damage to the PFC early in life impairs the ability to grasp moral concepts and can lead to psychopathic behavior. Men accused of murder often display malfunctions of the PFC. The first signs of frontotemporal dementia, a disorder that starts in the PFC, often take the form of antisocial, delinquent behavior, including sexual harassment, assault, robbery, burglary, hit-and-run crimes, and pedophilia. It usually takes a while for behavioral aberrations of this kind to be identified as the onset of such dementia. The PFC plays a central role when we face moral dilemmas, like whether to sacrifice the life of a single individual to save many lives. Most people find such decisions impossibly difficult, but individuals with damage to the PFC approach them very cold-bloodedly, being much more dispassionate and impersonal in their reasoning.

Besides the PFC, other cortical and subcortical areas of the brain play an important role in moral functioning, including the foremost part of the temporal lobe and the almond-shaped structure within it (the amygdala), the septum (the structure separating the ventricles of the brain,
fig. 26
), the reward circuitry (the ventral tegmental area/nucleus accumbens,
fig. 16
), and the hypothalamus (
fig. 18
) in the base of the brain. All of these areas are essential for the motivation and emotions that underlie moral behavior. The amygdala is also involved in calculating the social significance of facial expressions and the appropriate response. Along with abnormalities of the temporal lobe, malfunctions of the amygdala have been found in the brains of murderers and psychopaths, explaining why the latter are less responsive when their victims express grief and fear. Humans instinctively dislike acts that are inspired by evil motives. Malicious acts are condemned and in a criminal context result in stiffer sentences. But if you disable someone's moral circuitry (using transcranial magnetic stimulation to disrupt the right temporoparietal
junction—the place where the temporal and parietal lobes meet) he no longer cares whether a person's motives are moral or not, since he can no longer understand the motivation behind an action.

So our moral networks aren't just confined to the neocortex, a comparatively new area of the brain. Much more ancient regions are equally crucial for our moral functioning. Typically moral emotions like guilt, pity, empathy, shame, pride, contempt, and gratitude, as well as disgust, respect, indignation, and anger, depend on interaction between the above-mentioned areas. Functional brain scans performed during tests in which people were confronted with terrible moral dilemmas, like suffocating a crying baby in order to save a number of lives, have revealed changes in patterns of activity in brain regions that we know (from the effects of damage or tumors) to be linked with moral functioning.

But we mustn't forget, when reflecting on our finer moral impulses, that while empathy enables us to understand others and share their emotions, it also allows us to imagine what others would go through if we deliberately hurt or tortured them, and these feelings, too, can be indulged in.

WHAT NATURE TEACHES US ABOUT A BETTER SOCIETY

Man is a chimpanzee with ideas above his station.

Bert Keizer,
Alzheimer Opera

Frans de Waal is a world-famous Dutch primatologist who has worked in the United States since 1981 and has recently published his ninth book, a fascinating work optimistically titled
The Age of Empathy: Nature's Lessons for a Kinder Society.
In it he again draws parallels between human and animal behavior. The message of the book is that the age of empathy has dawned. The misguided belief of the Thatcher/Reagan era, that a free market economy would be self-regulating, culminated, under George W. Bush, in the nightmare of
the financial crisis. It's time to call corporate greed to a halt, to curtail the covetous culture of CEOs and bankers. “Greed is out, empathy is in,” claims De Waal. Humans aren't just the most aggressive primates but also the most empathetic, as shown by the aid response in the wake of Hurricane Katrina in 2005 and the Chinese earthquake of 2008. It's all a question of balance, something that has been conspicuously lacking in recent years. According to De Waal, empathy—the ability to relate to the feelings of others—needs to regain the upper hand. Empathy has a long evolutionary history, stretching back over 200 million years of mammalian development—which should provide a solid foundation for such a change. You might wonder whether De Waal is guilty of wishful thinking, but since the G20 summit agreed to curb the bonus culture in 2009, it's beginning to look as though he might just be right. De Waal is a diehard Darwinist who demonstrates that, as far as emotions are concerned, the entire spectrum of behavior is already to be found in the animal world. Like Darwin, De Waal writes clearly and appealingly, illustrating each crucial step of his arguments with fascinating examples taken from the entire animal kingdom. He also proves his theories through a great many ingenious experiments. De Waal has one advantage over Darwin, however: a much better sense of humor.

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